WO2019127572A1 - 感光驱动电路及感光装置、电子设备 - Google Patents
感光驱动电路及感光装置、电子设备 Download PDFInfo
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- WO2019127572A1 WO2019127572A1 PCT/CN2017/120400 CN2017120400W WO2019127572A1 WO 2019127572 A1 WO2019127572 A1 WO 2019127572A1 CN 2017120400 W CN2017120400 W CN 2017120400W WO 2019127572 A1 WO2019127572 A1 WO 2019127572A1
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V10/00—Arrangements for image or video recognition or understanding
- G06V10/10—Image acquisition
Definitions
- the utility model relates to a photosensitive driving circuit, a photosensitive device and an electronic device for sensing biological characteristic information.
- optical fingerprint recognition has gradually become a standard component of electronic products such as mobile terminals. Since optical fingerprint recognition has stronger penetrability than capacitive fingerprint recognition, the application of optical fingerprint recognition to mobile terminals is a future development trend. However, the existing optical fingerprint recognition structure applied to mobile terminals still needs to be improved.
- the embodiments of the present invention aim to at least solve one of the technical problems existing in the prior art. Therefore, the embodiments of the present invention need to provide a photosensitive driving circuit, a photosensitive device, and an electronic device.
- a photosensitive driving circuit for sequentially driving the plurality of photosensitive pixels to perform light sensing; and after the photosensitive pixels start performing light sensing, controlling the photosensitive pixels to perform light sensing Electrical signal output.
- the light sensing method of the embodiment of the present invention can not only control the light sensing time of the photosensitive pixel, but also realize the timely and effective output of the electrical signal generated by the photosensitive unit by outputting the control signal, thereby improving the sensing precision.
- the output of the photosensitive signal of the photosensitive pixel is controlled by the output control signal, so that the signal of the photosensitive pixel is isolated from the output end, and other circuit loads are prevented from affecting the photosensitive signal of the photosensitive pixel, thereby obtaining an accurate photosensitive signal, thereby further improving the sensing precision.
- the plurality of photosensitive pixels are arranged in an array on a substrate, and the substrate is further provided with a plurality of first scan lines respectively electrically connected to the plurality of photosensitive pixels;
- the photosensitive drive circuit includes:
- the first driving circuit is electrically connected to the first scan line, and is configured to provide a first scan driving signal to the plurality of photosensitive pixels row by row or interlaced to drive the plurality of photosensitive pixels row by row or interlaced Perform light sensing.
- the first driving circuit is further configured to:
- the first scan driving signal is further supplied to the photosensitive pixels of the next row.
- the photosensitive device in the embodiment of the present invention performs light sensing
- the photosensitive pixels of the current row perform light sensing
- the photosensitive signals generated when performing the light sensing are read
- the photosensitive pixels of the next row are executed.
- the sensing is such that the reading of the photosensitive signals of each row of photosensitive pixels does not interfere with each other, so that an accurate photosensitive signal can be obtained.
- the photosensitive device since the photosensitive device takes a long time to perform one light sensing, it can be used as a test mode.
- the first driving circuit is further configured to:
- the predetermined time is at least one clock cycle.
- the embodiment of the present invention reduces the time for performing the light sensing by the photosensitive device by the method of rolling the photosensitive device, and the time for all the photosensitive pixels to wait for reading the photosensitive signal is also the same, that is, the charge leakage to the photosensitive signal is solved.
- the impact of the acquisition increases the accuracy of the sensing.
- the substrate further includes a plurality of second scan lines electrically connected to the plurality of photosensitive pixels;
- the photosensitive driving circuit further includes: a second driving circuit, the second driving circuit Correspondingly electrically connected to the second scan line, when each photosensitive pixel starts performing light sensing and reaches a fourth predetermined time, providing the output control signal to the photosensitive pixel to control the photosensitive pixel to perform light The electrical signal output generated during sensing.
- the second driving circuit is further configured to: control an electrical signal output generated when the photosensitive pixel performs photo sensing for a second predetermined time.
- the second predetermined time is dynamically adjusted based on the intensity of the received optical signal.
- the embodiment of the present invention timely adjusts the reading time of the electrical signal generated by the photosensitive pixel according to the intensity of the optical signal, thereby ensuring accurate reading of the electrical signal, thereby improving the sensing accuracy.
- the substrate further includes a data line electrically connected to the plurality of photosensitive pixels;
- the photosensitive driving circuit further includes a signal processing unit, the signal processing unit and the plurality of data And a line electrical connection for reading an electrical signal output by the photosensitive pixel, and obtaining predetermined biometric information of the target object contacting or approaching the photosensitive pixel according to the read electrical signal.
- the photosensitive driving circuit is formed on the substrate or electrically connected to the plurality of photosensitive pixels through an electrical connection; or a part of the circuit of the photosensitive driving circuit is formed in the On the substrate, another part of the circuit is electrically connected to the plurality of photosensitive pixels through a connecting member.
- a photosensitive device includes a plurality of photosensitive pixels and a photosensitive driving circuit of any one of the above embodiments, wherein the photosensitive driving circuit is configured to drive the plurality of photosensitive pixels to perform light sensing, and After the photosensitive pixel starts performing light sensing, it controls the electrical signal output generated when the photosensitive pixel performs light sensing.
- the photosensitive device is a fingerprint sensing device for collecting fingerprint information of a finger.
- the photosensitive device is a biosensing chip for acquiring predetermined biometric information of a target object that is in proximity to or in contact with the photosensitive device.
- An electronic device includes the photosensitive device of any of the above embodiments.
- FIG. 1 is a schematic view showing an array of photosensitive pixels in a photosensitive device according to an embodiment of the present invention
- FIG. 2 is a schematic diagram showing the circuit structure of an embodiment of the photosensitive pixel shown in FIG. 1;
- FIG. 3 is a timing diagram of signals at respective nodes when the photosensitive pixel shown in FIG. 2 performs light sensing
- FIG. 4 is a structure of a connection relationship between a photosensitive pixel and a scan line, a data line, and a signal reference line in the photosensitive device according to an embodiment of the present invention, and the photosensitive pixel is a photosensitive pixel structure shown in FIG. 2;
- FIG. 5 is a block diagram showing the structure of an embodiment of the photosensitive driving unit shown in Figure 4;
- FIG. 6 is a signal timing diagram of an embodiment in which the photosensitive device shown in FIG. 4 performs light sensing
- FIG. 7 is a signal timing diagram of another embodiment in which the photosensitive device shown in FIG. 4 performs light sensing
- FIG. 8 is a schematic circuit diagram of another embodiment of the photosensitive pixel shown in FIG. 1;
- FIG. 9 is a timing chart of signals at each node when the photosensitive pixel shown in FIG. 8 performs light sensing
- FIG. 10 is a structure of a connection relationship between a photosensitive pixel and a scan line, a data line, and a signal reference line in the photosensitive device according to an embodiment of the present invention, and the photosensitive pixel is a photosensitive pixel structure shown in FIG. 8;
- FIG 11 is a block diagram showing the structure of an embodiment of the photosensitive driving unit shown in Figure 10;
- FIG. 12 is a schematic structural view of a photosensitive panel in a photosensitive device according to an embodiment of the present invention.
- FIG. 13 is a schematic flow chart of a light sensing method of a photosensitive device according to an embodiment of the present invention.
- FIG. 14 is a schematic structural view of an electronic device to which a photosensitive device according to an embodiment of the present invention is applied;
- FIG. 15 is a cross-sectional view of the electronic device shown in FIG. 14 taken along line I-I, and FIG. 15 shows a partial structure of the electronic device;
- 16 is a schematic view showing a corresponding position of a display area of a display panel and a sensing area of the photosensitive panel according to an embodiment of the present invention
- FIG. 17 is a schematic structural view of an electronic device to which a photosensitive device according to an embodiment of the present invention is applied;
- FIG. 18 is a cross-sectional view of the electronic device shown in FIG. 17 taken along line II-II, and FIG. 18 shows a partial structure of the electronic device.
- first and second are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. .
- features defining “first” or “second” may include one or more of the described features either explicitly or implicitly.
- the meaning of "a plurality” is two or more unless specifically and specifically defined otherwise.
- Contact or “touch” includes direct or indirect contact.
- connection is to be understood broadly, and may be, for example, a fixed connection or a Disassembling the connection, or connecting integrally; may be mechanical connection, electrical connection or communication with each other; may be directly connected, or may be indirectly connected through an intermediate medium, may be internal communication of two elements or mutual interaction of two elements Role relationship.
- installation is to be understood broadly, and may be, for example, a fixed connection or a Disassembling the connection, or connecting integrally; may be mechanical connection, electrical connection or communication with each other; may be directly connected, or may be indirectly connected through an intermediate medium, may be internal communication of two elements or mutual interaction of two elements Role relationship.
- the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.
- the embodiment of the present invention provides a photosensitive device disposed in an electronic device, especially disposed under the display screen of the electronic device.
- the display screen has a display device that emits an optical signal, such as, but not limited to, an OLED display panel.
- the display emits an optical signal to perform the corresponding image display.
- the target object touches or touches the electronic device
- the light signal emitted by the display screen reaches the target object and reflects, and the reflected light signal passes through the display screen and is received by the photosensitive device, and the light receiving device receives the light signal. Converting to an electrical signal corresponding to the optical signal to form predetermined biometric information of the target object based on the electrical signal generated by the photosensitive device.
- the biometric information of the target object is, for example but not limited to, skin texture information such as fingerprints, palm prints, ear prints, and soles, and other biometric information such as heart rate, blood oxygen concentration, and veins.
- the target object such as but not limited to a human body, may also be other suitable types of objects.
- the electronic device can also provide a light source for biometric information sensing.
- the light source emits a corresponding optical signal, such as infrared light, to achieve sensing of heart rate, blood oxygen concentration, veins, and the like of the target object.
- Electronic devices such as, but not limited to, suitable types of electronic products such as consumer electronics, home electronics, vehicle-mounted electronic products, and financial terminal products.
- consumer electronic products such as mobile phones, tablets, notebook computers, desktop monitors, computer integrated machines.
- Home-based electronic products such as smart door locks, TVs, refrigerators, wearable devices, etc.
- Vehicle-mounted electronic products such as car navigation systems, car DVDs, etc.
- Financial terminal products such as ATM machines, terminals for self-service business, etc.
- FIG. 1 shows an array distribution structure of photosensitive pixels in a photosensitive device.
- the photosensitive device 20 includes a plurality of photosensitive pixels 22, and the plurality of photosensitive pixels 22 are arrayed in a matrix to form a photosensitive array 201.
- the photosensitive array 201 includes a plurality of rows of photosensitive pixels and a plurality of columns of photosensitive pixels, and each row of photosensitive pixels is spaced apart in the X direction, and each column of the photosensitive pixels is spaced apart in the Y direction.
- each row of the photosensitive pixels 22 can be driven from the X direction to perform light sensing, and the electrical signals generated by the respective photosensitive pixels 22 to perform light sensing can be read from the Y direction.
- each of the photosensitive pixels 22 forming the photosensitive array 201 is not limited to the vertical relationship shown in FIG. 1, and may be distributed in other regular manners or in an irregular manner.
- each photosensitive pixel 22 includes a sensing unit and a signal output unit.
- the sensing unit is configured to receive a light sensing control signal, and perform light sensing when receiving the light sensing control signal.
- the sensing unit receives the optical signal and converts the received optical signal into a corresponding photosensitive signal, that is, an electrical signal;
- the signal output unit is configured to receive the output control signal and receive the output control signal When the control signal is output, the sensing unit outputs a light sensing signal generated when the light sensing is performed.
- FIG. 2 shows a circuit configuration of one photosensitive pixel 22 of FIG. 1. Therefore, the photosensitive pixel 22 can also be referred to as a photosensitive circuit.
- a photosensitive pixel 22 in the embodiment of the present invention has a first input terminal In1, a second input terminal In2, a third input terminal In3, and a first output terminal Out1.
- the light sensing control signal includes a first scan driving signal.
- the photosensitive pixel 22 includes a sensing unit and a signal output unit 223.
- the sensing unit further includes a switching unit 221 and a photosensitive unit 222.
- the photosensitive unit 222 is connected between the switching unit 221 and the signal output unit 223.
- the switch unit 221 receives a reference signal Vref through the third input terminal In3.
- the switch unit 221 further receives a first scan driving signal through the first input terminal In1, and transmits the reference signal Vref when receiving the first scan driving signal.
- the photosensitive unit 222 is driven to drive the photosensitive unit 222 to operate.
- the photosensitive unit 222 is configured to receive an optical signal and convert the received optical signal into a corresponding electrical signal when the optical signal is received.
- the signal output unit 223 receives the output control signal through the second input terminal In2, and outputs the electrical signal generated by the photosensitive unit 222 from the first output terminal Out1 according to the output control signal.
- the first scan driving signal and the output control signal are both a pulse signal, and a duration of a high level in the first scan driving signal is a first predetermined time, and a duration of a high level in the output control signal is a second scheduled time.
- the photosensitive unit 222 includes a photosensitive device including a first electrode for receiving the reference signal Vref transmitted by the switching unit 221 and a second electrode for receiving A fixed electrical signal.
- a driving voltage for driving the photosensitive device is formed by applying a reference signal Vref and a fixed electrical signal to both electrodes of the photosensitive device.
- the photosensitive device is, for example but not limited to, a photodiode D1, which may alternatively be a photo resistor, a phototransistor, a thin film transistor or the like. It should be noted that the number of photosensitive devices may also be two, three, and the like.
- the photodiode D1 includes a positive electrode and a negative electrode, wherein the positive electrode receives a predetermined electrical signal, such as a ground signal NGND; and the negative electrode serves as a first electrode of the photosensitive device for receiving the reference signal Vref transmitted by the switching unit 221. . It should be noted that as long as the reference signal Vref is applied to both ends of the photodiode D1 corresponding to the predetermined signal, a reverse voltage can be formed across the photodiode D1, thereby driving the photodiode D1 to perform photo sensing.
- the reference signal Vref When the switch unit 221 is closed, the reference signal Vref is transmitted to the negative terminal of the photodiode D1 through the closed switch unit 221, and since the photodiode D1 has an equivalent capacitance inside, the reference signal Verf performs the equivalent capacitance inside the photodiode D1. Charging, so that the voltage Vg on the negative electrode of the photodiode D1 gradually rises and reaches the first predetermined time, the voltage Vg reaches the voltage value of the reference signal Vref and remains unchanged. At this time, the voltage difference across the photodiode D1 will reach the reverse voltage at which the photodiode is driven, that is, the photodiode D1 is in operation.
- the switching unit 221 Since the first scan driving signal is turned to a low level signal when the first predetermined time arrives, the switching unit 221 is turned off according to the low level signal, and a discharge loop is formed inside the photodiode D1. At this time, if an optical signal is incident on the photodiode D1, the reverse current of the photodiode D1 rapidly increases, so that the voltage Vg on the negative node of the photodiode D1 changes, that is, gradually decreases. Moreover, since the intensity of the optical signal is larger, the reverse current generated by the photodiode D1 is also larger, and the rate of decrease of the voltage Vg at the negative node of the photodiode D1 is faster.
- the photosensitive unit 222 further includes a first capacitor c1.
- the first capacitor c1 is used to form a discharge loop with the photosensitive device when performing light sensing to obtain a corresponding photosensitive signal.
- the first capacitor c1 is disposed in parallel with the photosensitive device, that is, the first plate of the first capacitor c1 is connected to the cathode of the photodiode D1, and the second plate of the first capacitor c1 is connected to a predetermined one.
- An electrical signal such as the ground signal NGND.
- the first capacitor c1 When the reference signal Vref is transmitted to the negative electrode of the photodiode D1, the first capacitor c1 is also charged, and when the switch unit 221 is turned off, the first capacitor c1 forms a discharge loop with the photodiode D1, and the first capacitor c1
- the voltage of one plate ie, voltage Vg
- the capacitance capacity of the photosensitive unit 222 is increased, thereby reducing the voltage drop speed on the negative electrode of the photodiode D1, thereby ensuring that an effective photosensitive signal is obtained, and the sensing accuracy of the photosensitive device 20 on the target object is improved.
- the first capacitor c1 is a variable capacitor, for example, a capacitor array formed by a plurality of capacitors, and the plurality of capacitors are disposed in parallel, and the capacity change of the first capacitor c1 is realized by controlling whether the plurality of capacitors are connected. Since the first capacitor c1 is set as a variable capacitor, the capacity adjustment of the first capacitor c1 is adapted to the change of the received optical signal, thereby obtaining an accurate and effective photosensitive signal. Specifically, if the intensity of the received optical signal is larger, the capacity of the first capacitor c1 is larger, and if the intensity of the received optical signal is smaller, the capacity of the first capacitor c1 is smaller.
- the switching unit 221 includes a first transistor T1, such as but not limited to any one or several of a triode, a MOS transistor, and a thin film transistor.
- the first transistor T1 includes a first control electrode C1, a first transfer electrode S1, and a second transfer electrode S2, wherein the first control electrode is a gate of the MOS transistor, and the first transfer electrode S1 is a MOS transistor.
- the drain of the second transfer electrode S2 is the source of the MOS transistor.
- the first control electrode C1 is connected to the first input terminal In1 for receiving the first scan driving signal; the first transfer electrode S1 is connected to the third input terminal In3 for receiving the reference signal Vref; the second transfer electrode S2 and the photosensitive unit
- the negative electrode of the photodiode D1 is connected in 222.
- signal output unit 223 includes a second transistor T2 and a buffer circuit.
- the snubber circuit is used to buffer the electrical signal generated by the photosensitive unit 222.
- the second transistor T2 is, for example but not limited to, one or more of a triode, a MOS transistor, and a thin film transistor. Taking the MOS transistor as an example, the second transistor T2 includes a second control electrode C2, a third transfer electrode S3, and a fourth transfer electrode S4, wherein the second control electrode C2 is the gate of the MOS transistor, and the third transfer electrode S3 is the MOS transistor. The drain of the fourth transfer electrode S4 is the source of the MOS transistor.
- the second control electrode C2 is connected to the second input terminal In2 for receiving an output control signal;
- the third transmission electrode S3 is connected to the buffer circuit for receiving an electrical signal output by the buffer circuit;
- the fourth transmission electrode S4 is The first output terminal Out1 is connected for outputting an electrical signal buffered by the buffer circuit.
- a buffer circuit is connected between the photosensitive unit 222 and the second transistor T2 for buffering the electrical signal converted by the photosensitive unit 222, and outputs a buffered electrical signal when the second transistor T2 is turned on.
- the buffer circuit includes a third transistor T3, such as but not limited to any one or several of a triode, a MOS transistor, and a thin film transistor.
- the third transistor T3 includes a third control electrode C3, a fifth transmission electrode S5, and a sixth transmission electrode S6, wherein the third control electrode C3 is the gate of the MOS transistor, and the fifth transmission electrode S5 is the MOS.
- the drain of the tube, the sixth transfer electrode S6 is the source of the MOS tube.
- the third control electrode C3 is connected to the negative electrode of the photodiode D1 for receiving an electrical signal generated when the photodiode D1 performs photo sensing; the fifth transmission electrode S5 is for receiving a voltage signal Vcc; and the sixth transmission electrode S6 is second.
- the third transfer electrode S3 of the transistor T2 is connected for outputting a buffered electrical signal when the second transistor T2 is turned on.
- the voltage Vs of the sixth transfer electrode S6 changes according to the voltage Vg of the third control electrode C3, that is, the sixth transfer electrode S6 is not affected regardless of the circuit load connected to the sixth transfer electrode S6. Voltage. Moreover, due to the transistor characteristics, the voltage Vs is always lower than the voltage Vg by a threshold voltage which is the threshold voltage of the third transistor T3. Therefore, the buffer circuit functions as a buffer isolation to isolate the electrical signal generated when the photosensitive unit 222 performs light sensing, thereby preventing other circuit loads from affecting the photosensitive signal generated by the photosensitive unit 222, thereby ensuring accurate execution of the photosensitive pixel 22. The light sensing improves the sensing accuracy of the photosensitive device 20 on the target object.
- FIG. 3 shows the signal timing at each node when the photosensitive pixel 22 shown in FIG. 2 performs light sensing, wherein Vg is the voltage on the negative electrode of the photodiode D1, and is also the third of the third transistor T3. The voltage on the electrode C3 is controlled; Vs is the voltage on the sixth transfer electrode S6 of the third transistor T3.
- the first scan driving signal is input through the first input terminal In1, so that the first transistor T1 is turned on and continues for a first predetermined time (ie, t2-t1), and is turned off.
- the reference signal Vref is turned on.
- the first transfer electrode S1 and the second transfer electrode S2 are transmitted to the negative electrode of the photodiode D1 and the first plate of the first capacitor c1. Since the photodiode D1 has an equivalent capacitance inside, the reference signal Verf charges the equivalent capacitance inside the photodiode D1, so that the voltage Vg on the negative electrode of the photodiode D1 gradually rises and reaches the voltage value of the reference signal Vref. constant.
- the reference signal Vref also charges the first capacitor c1, so that the voltage on the first plate gradually rises and remains unchanged after reaching the voltage value of the reference signal Vref. .
- the first scan driving signal changes from a high level to a low level signal, that is, the first input terminal In1 becomes a low level signal, the first transistor T1 is turned off, the equivalent capacitance and the first capacitance c1 and the photodiode D1 A discharge loop is formed between them. If there is an optical signal on the photodiode D1, a current signal proportional to the optical signal is generated inside the photodiode D1, and thus the voltage Vg on the negative electrode of the photodiode D1 gradually decreases. Moreover, the stronger the optical signal, the faster the voltage Vg is lowered.
- the voltage Vs on the sixth transfer electrode S6 of the third transistor T3 changes with the voltage Vg on the negative electrode of the photodiode D1, and the voltage Vs is always lower than the voltage Vg by Vth, which Vth is the threshold voltage of the third transistor T3.
- the first predetermined time is to ensure that the photodiode and the first capacitor c1 in the photosensitive unit 22 are charged to the reference signal Vref.
- the second control terminal In2 inputs and outputs a control signal, and the second transistor T2 is turned on according to the high level signal.
- the voltage Vs on the sixth transfer electrode S6 of the third transistor T3 is output from the first output terminal Out1 via the third transfer electrode S3 and the fourth transfer electrode S4 of the second transistor T2.
- the voltage outputted by the first output terminal Out1 is gradually increased from a low level to a voltage Vs on the sixth transfer electrode S6, and then changes in accordance with a change in the voltage Vs on the sixth transfer electrode S6.
- the fourth predetermined time is at least one clock cycle, and the fourth predetermined time is not too long, and of course, cannot be too short, so as to ensure that the photosensitive signal generated when the photosensitive unit 222 performs light sensing can be effectively and timely. Output.
- the output control signal changes from a high level signal to a low level signal, that is, the second input terminal In2 becomes a low level signal, the second transistor T2 is turned off, and the voltage outputted by the first output terminal Out1 gradually decreases or remains unchanged. change.
- the output voltage of the first output terminal Out1 needs to gradually drop to a low level.
- the voltage Vs on the sixth transfer electrode S6 of the third transistor T3 (that is, the voltage Vg on the negative electrode of the photodiode D1) will be from the time between the time t4 and the time t3, that is, the second predetermined time ⁇ t1.
- the first output terminal Out1 is outputted. Therefore, by reading the voltage signal of the first output terminal Out1, the size of the photosensitive signal generated by the photodiode D1 due to the reception of the optical signal can be obtained, thereby generating biometric information of the target object.
- the second predetermined time ⁇ t1 may be a fixed value or a change value. Due to the larger the optical signal received by the photodiode D1, the faster the voltage Vg falls, and the faster the voltage Vs falls. Therefore, in order to achieve accurate and efficient acquisition of the photosensitive signal, according to the intensity of the received optical signal. Adjust the size of ⁇ t1. Specifically, the greater the intensity of the optical signal, the shorter the second predetermined time ⁇ t1; the smaller the intensity of the optical signal, the longer the second predetermined time ⁇ t1.
- FIG. 4 shows a connection structure of the photosensitive pixels 22 in the photosensitive device 20 with respective scan lines, data lines, and signal reference lines, and the photosensitive pixels are the circuit structure shown in FIG. .
- the photosensitive device 20 further includes a scan line group, a data line group, and a signal reference line group electrically connected to the plurality of photosensitive pixels 22.
- the scan line group includes a first scan line group composed of a plurality of first scan lines and a second scan line group composed of a plurality of second scan lines
- the data line group includes a plurality of data lines
- the signal reference line group includes Multiple signal reference lines.
- a row of photosensitive pixels in the X direction includes n photosensitive pixels 22 arranged at intervals, and a column of photosensitive pixels in the Y direction includes m photosensitive pixels 22 arranged at intervals, thereby
- the photosensitive array 201 includes a total of m*n photosensitive pixels 22.
- the first scan line group includes m first scan lines, and the m first scan lines are arranged along the Y direction, for example, G11, G12, . . . G1m; the second scan line group further includes m second scans.
- the scan line group, the data line group, and the signal reference line group of the photosensitive device 20 may also be distributed in other regular manners or in an irregular manner.
- the first scan line, the second scan line, the signal reference line, and the data line are electrically conductive, the first scan line, the second scan line, the signal reference line, and the data line at the intersection position are made of an insulating material. isolation.
- the m first scan lines are connected to the first input end In1 of the plurality of photosensitive pixels 22, and the m second scan lines are connected to the second input end In2 of the plurality of photosensitive pixels 22, and the m signal reference lines are connected.
- the n data lines are connected to the first output end Out1 of the plurality of photosensitive pixels 22.
- the first scan line, the second scan line, and the signal reference line are all drawn from the X direction, and the data line is taken out from the Y direction.
- the photosensitive device 20 further includes a photosensitive driving circuit for sequentially driving the plurality of photosensitive pixels 22 to perform light sensing; after the photosensitive pixels 22 start performing light sensing, controlling The photosensitive pixel 22 performs an electrical signal output generated when light sensing is performed.
- the photosensitive driving circuit includes a photosensitive driving unit 24, and the first scanning line, the second scanning line, and the signal reference line in the photosensitive device 20 are all connected to the photosensitive driving unit 24.
- FIG. 5 shows the structure of an embodiment of the photosensitive driving unit 24 of FIG.
- the photosensitive driving unit 24 includes a first driving circuit 241 that supplies a first scan driving signal, a second driving circuit 242 that provides an output control signal, and a reference circuit 243 that supplies a reference signal Vref.
- the circuits of the photosensitive driving unit 24 can be integrated into one control chip through a silicon process. Of course, the circuits of the photosensitive driving unit 24 can also be formed separately in different control chips.
- the first driving circuit 241 and the second driving circuit 242 are formed on the same substrate together with the photosensitive pixels 22, and the reference circuit 243 passes through a connecting member (for example, a flexible circuit board) and a plurality of signal reference lines on the photosensitive device 20. connection.
- a connecting member for example, a flexible circuit board
- the reference circuit 243 is configured to provide a reference signal Vref that is selectable by a first switch of the photosensitive pixel 22 (eg, the first transistor T1 in the switching unit 221 shown in FIG. 2) The ground is electrically connected to the photosensitive unit 222. When the first switch is closed, the reference signal Vref is transmitted to the corresponding photosensitive unit 222 through the closed first switch.
- the first driving circuit 241 is electrically connected to the first scan line of the photosensitive device 20 for providing a first scan driving signal to the first switch in the photosensitive pixel 22 row by row or interlaced to control the first switch to be closed, and in the first When a predetermined time arrives, the first switch is controlled to be turned off, thereby driving the photosensitive unit 222 to start performing light sensing.
- the second driving circuit 242 is electrically connected to the second scan line of the photosensitive device 20 for performing light sensing at each photosensitive pixel and reaching a fourth predetermined time, that is, the first switch is turned off and reaches a fourth predetermined time. (for example, t3-t2 shown in FIG. 3), an output control signal is supplied to the second switch in the photosensitive pixel 22 (for example, the second transistor T2 in the signal output unit 223 shown in FIG. 2), and the second is controlled. The switch is closed to cause the photosensitive unit 222 to output an electrical signal generated when the light is sensed.
- the first driving circuit 241 is further configured to: provide the first scan driving signal to the photosensitive pixel of the current row, and provide the output control signal to the photosensitive pixel of the current row, After the light sensing is performed by driving the photosensitive pixel of the current line, and the electrical signal generated when the photosensitive pixel performs light sensing is controlled to be output, the first scanning driving signal is further supplied to the photosensitive pixel of the next row.
- the photosensitive pixels of the next row herein are not limited to one row of photosensitive pixels adjacent to the photosensitive pixels of the current row, and may also be referred to as interlaced photosensitive pixels.
- FIG. 6 shows a timing when the photosensitive device shown in FIG. 4 performs light sensing, and the photosensitive device performs light sensing by progressively sensing in a line-by-line manner.
- time t 1 a first scan driving signal to the sensing pixels in the first row, the first row to drive the photosensitive pixels perform light sensing
- t 2 time provides an output control signal to the photosensitive pixels of the first row, in order to control the first photosensitive photosensitive pixel output signal line
- t 3 time providing the photosensitive pixels of the first scan driving signal to the second row, the second row to drive the photosensitive pixels perform light sensing
- t 4 time provides an output control signal to the second line Sensing pixel to control the photosensitive signal output of the second row of the photosensitive signal...
- t 2m-1 providing the first scan driving signal to the photosensitive pixel of the mth row to drive the mth row of photosensitive pixels to perform light sensing
- an output control signal is supplied to the photosensitive pixels of the mth line to control the photosensitive pixels of the mth line to output a photosensitive signal.
- the photosensitive device in the embodiment of the present invention performs light sensing
- the photosensitive pixels of the current row perform light sensing
- the photosensitive signals generated when performing the light sensing are read
- the photosensitive pixels of the next row are executed.
- the sensing is such that the reading of the photosensitive signals of each row of photosensitive pixels does not interfere with each other, so that an accurate photosensitive signal can be obtained.
- the photosensitive device since the photosensitive device takes a long time to perform one light sensing, it can be used as a test mode.
- the first driving circuit 241 is further configured to: when the first scan driving signal is supplied to the photosensitive pixel of the current row and reach a predetermined time, the first scan driving signal is provided to the next row Sensing pixels; the predetermined time is at least one clock cycle.
- the photosensitive signals in the photosensitive pixels 22 are output through the control of the output control signals, the light sensing times of the photosensitive pixels of different rows may overlap, that is, when the photosensitive pixels of the current row perform light sensing, the first scan may be provided.
- the driving signal is sent to the photosensitive pixel of the next row to drive the photosensitive pixel to perform light sensing.
- the photosensitive pixels of the next row herein are not limited to one row of photosensitive pixels adjacent to the photosensitive pixels of the current row, and may also be referred to as interlaced photosensitive pixels.
- a timing when the photosensitive device shown in Fig. 4 performs light sensing, which performs rolling sensing in a line-by-line manner time t 11, a first scan driving signal to the sensing pixels in the first row, the first row to drive the photosensitive pixels perform light sensing, t 12 time, providing a first driving signal to the scan line of the photosensitive pixel 2, to drive line 2 performs light sensing photosensitive pixels, t 13 time, providing a first driving signal to the scanning line 3 of the photosensitive pixel, to drive the third row of pixels perform light sensing photosensitive, so, t 1m time, providing a first A scan driving signal is applied to the photosensitive pixels of the mth row to drive the mth row of photosensitive pixels to perform light sensing.
- an output control signal is supplied to the photosensitive pixels of the row.
- t 21 time provides an output control signal to the photosensitive pixels of the first row, in order to control the photosensitive signal output line of the first photosensitive pixels
- t 22 time supplied to the second row of the photosensitive pixel outputs a control signal to control the second row of the photosensitive The photosensitive signal output of the pixel.
- the time required for the photosensitive device 20 to perform the light sensing is short, and the time for all the photosensitive pixels to wait for reading the photosensitive signal is also the same, that is, the influence of the charge leakage on the photosensitive signal collection is solved, thereby improving the effect. Sensing accuracy.
- the photosensitive driving circuit further includes a signal processing unit 25, and the data lines in the photosensitive device 20 shown in FIG. 4 are connected to the signal processing unit 25, and the signal processing unit 25 can be Integrated in a test chip by a silicon process.
- the signal processing unit 25 can also be integrated with the photosensitive driving unit 24 in one processing chip.
- the signal processing unit 25 is configured to read an electrical signal generated when the photosensitive unit 222 performs light sensing, and obtain a predetermined biological object that contacts or approaches the target object of the photosensitive panel according to the read electrical signal. Feature information. It can be understood that, in order to collect an accurate and effective electrical signal, the signal processing unit 25 can perform multiple readings on the electrical signal generated when the photosensitive unit 222 performs light sensing for a second predetermined time.
- the signal processing unit 25 includes a plurality of processing channels, and optionally each processing channel is connected to a data line. However, it is also possible to change at least two data lines corresponding to each processing channel, and to select an electrical signal on one data line each time by means of time division multiplexing, and then select another data line. Electrical signals, and so on, until the electrical signals on all data lines are read. In this way, the number of processing channels can be reduced, thereby saving the cost of the photosensitive device 20.
- FIG. 8 shows another circuit structure of one photosensitive pixel 22 in FIG.
- a photosensitive pixel 22 in the embodiment of the present invention has a first input terminal In1', a second input terminal In2', a third input terminal In3', a fourth input terminal In4, and a first output terminal Out1' and a second Output Out2.
- the light sensing control signal includes a first scan driving signal.
- the photosensitive pixel 22 includes a sensing unit and a signal output unit 223'.
- the sensing unit specifically includes a switching unit 221' and a photosensitive unit 222'.
- the switch unit 221' receives a reference signal Vref through the third input terminal In3'.
- the switch unit 221' further receives a first scan driving signal through the first input terminal In1', and receives the first scan driving signal.
- the signal output unit 223' receives an output control signal through the second input terminal In2', and receives through the fourth input terminal In4.
- a constant electrical signal Is to convert the constant electrical signal Is into two different electrical signals according to an electrical signal generated when the photosensitive unit 222' performs light sensing upon receiving the output control signal, and from the first output terminal Out1' And outputted by the second output terminal Out2.
- the first scan driving signal and the output control signal are both a pulse signal, and the duration of the high level signal in the first scan driving signal is a first predetermined time, and the duration of the high level in the output control signal is Two scheduled times.
- the switch unit 221' when receiving the first scan driving signal, the switch unit 221' is closed according to the high level signal and turned off according to the low level signal. Therefore, the photosensitive unit 222' receives the reference signal Vref transmitted from the switching unit 221', and when the first predetermined time arrives, starts performing light sensing.
- the photosensitive unit 222' includes a first branch circuit 2221 and a second branch circuit 2222.
- the first branch circuit 2221 is configured to perform light sensing, that is, receive the optical signal, and convert the received optical signal into a corresponding electrical signal;
- the second branch circuit 2222 is configured to use the first end of the second branch circuit 2222.
- the electrical signal is maintained at the amplitude of the reference signal Vref.
- the photosensitive unit 222' is similar in structure to the photosensitive unit 222 shown in FIG. 2.
- the photosensitive unit 222' includes a second capacitor c2 in addition to the structure of the photosensitive unit 222 shown in FIG.
- the first capacitor c1 is the first branch circuit 2221 of the photosensitive unit 222'
- the second capacitor c2 is the second branch circuit 2222 of the photosensitive unit 222'.
- the first electrode of the photodiode D1 and the first plate of the first capacitor c1 are defined as the first end of the first branch circuit 2221, the anode of the photodiode D1 and the second plate of the first capacitor c1. It is the second end of the first branch circuit 2221.
- the operation principle of the first branch circuit 2221 is as described in the foregoing description.
- the first plate of the second capacitor c2 is used for receiving the reference signal Vref transmitted from the switch unit 221', and the second plate is for receiving a fixed electrical signal, such as the ground signal NGND.
- the reference signal Vref charges the second capacitor c2 such that the voltage Vn on the first plate of the second capacitor c2 gradually rises and remains unchanged after reaching the amplitude of the reference signal Vref.
- the first plate defining the second capacitor c2 is the first end of the second branch circuit 2222
- the second plate of the second capacitor c2 is the second end of the second branch circuit 2222.
- the switching unit 221 includes a fourth transistor T4 and a fifth transistor T5.
- the fourth transistor T4 and the fifth transistor T5 are, for example but not limited to, any one or several of a triode, a MOS transistor, and a thin film transistor.
- the fourth transistor T4 includes a fourth control electrode C4, a seventh transmission electrode S7, and an eighth transmission electrode S8, wherein the fourth control electrode C4 is the gate of the MOS transistor, and the seventh transmission electrode S7 is the MOS.
- the drain of the tube, the eighth transfer electrode S8 is the source of the MOS tube.
- the fifth transistor T5 includes a fifth control electrode C5, a ninth transfer electrode S9, and a tenth transfer electrode S10, wherein the fifth control electrode C5 is the gate of the MOS transistor, and the ninth transfer electrode S9 is the drain of the MOS transistor, the tenth The transfer electrode S10 is the source of the MOS transistor.
- the fourth control electrode C4 and the fifth control electrode C5 are both connected to the first input terminal In1' for receiving the first scan driving signal; the seventh transmitting electrode S7 and the ninth transmitting electrode S9 are both connected to the third input terminal In3'.
- the eighth transmission electrode S8 is connected to the first end of the first branch circuit 2221 of the photosensitive unit 222', and is configured to transmit the reference signal Vref to the photosensitive unit 222 when the fourth transistor T4 is turned on.
- a tenth transmission electrode S10 is coupled to the first end of the second branch circuit 2222 of the photosensitive unit 222' for transmitting the reference signal Vref to the photosensitive unit 222 when the fifth transistor T5 is turned on 'Second branch circuit 2222.
- the signal output unit 223' in the present embodiment includes a sixth transistor T6 and a conversion circuit 2231.
- the sixth transistor T6 is, for example but not limited to, one or more of a triode, a MOS transistor, and a thin film transistor.
- the sixth transistor T6 includes a sixth control electrode C6, an eleventh transmission electrode S11, and a twelfth transmission electrode S12, wherein the sixth control electrode C6 is the gate of the MOS transistor, and the eleventh transmission electrode S11 The drain of the MOS transistor, the twelfth transfer electrode S12 is the source of the MOS transistor.
- the sixth control electrode C6 is connected to the second input terminal In2' for receiving the output control signal; the eleventh transmission electrode S11 is connected to the fourth input terminal In4 for receiving a constant current signal Is, and the twelfth transmission electrode S12 It is connected to the conversion circuit 2231.
- the sixth transistor T6 is turned on according to an output control signal to transmit a constant current signal Is to the conversion circuit 2231.
- the conversion circuit 2231 includes a differential pair tube having three input terminals and two output terminals, wherein one input terminal is connected to the twelfth transmission electrode S12 of the sixth transistor T6 for receiving the sixth transistor
- the constant current signal Is is converted into two different current signals Ip and In, and the sum of the amplitudes of the two different current signals is equal to the amplitude of the constant current signal Is.
- the conversion circuit 2231 includes a seventh transistor T7 and an eighth transistor T8.
- the seventh transistor T7 and the eighth transistor T8 are, for example but not limited to, any one or more of a triode and a MOS transistor.
- the seventh transistor T7 includes a seventh control electrode C7, a thirteenth transmission electrode S13, and a fourteenth transmission electrode S14, wherein the seventh control electrode C7 is the gate of the MOS transistor, and the thirteenth transmission electrode S13 is the drain of the MOS transistor, and the fourteenth transfer electrode S14 is the source of the MOS transistor.
- the eighth transistor T8 includes an eighth control electrode C8, a fifteenth transmission electrode S15, and a sixteenth transmission electrode S16, wherein the eighth control electrode C8 is the gate of the MOS transistor, and the fifteenth transmission electrode S15 is the drain of the MOS transistor.
- the sixteenth transmission electrode S16 is the source of the MOS transistor.
- the seventh control electrode C7 of the seventh transistor T7 is connected to the first end of the first branch circuit 2221 (such as the first plate of the first capacitor c1); the twelfth transmission of the thirteenth transfer electrode S13 and the sixth transistor T6
- the electrode S12 is connected to receive the constant current signal Is transmitted by the sixth transistor T6; the fourteenth transmission electrode S14 is connected to the first output terminal Out1' for outputting a current signal Ip.
- the eighth control electrode C8 of the eighth transistor T8 is connected to the first end of the second branch circuit 2222 (such as the first plate of the second capacitor c2); the twelfth transmission of the fifteenth transfer electrode S15 and the sixth transistor T6
- the electrode S12 is connected for receiving the constant current signal Is transmitted by the sixth transistor T6; the sixteenth transmission electrode S16 is connected to the second output terminal Out2 for outputting another current signal In.
- the seventh transistor T7 and the eighth transistor T8 form a differential pair tube when the voltage Vp on the seventh control electrode C7 of the seventh transistor T7 and the voltage Vn on the eighth control electrode C8 of the eighth transistor T8 are equal.
- the differential pair tube is in an equilibrium state, and the fourteenth transfer electrode S14 of the seventh transistor T7 and the sixteenth transfer electrode S16 of the eighth transistor T8 output current signals of equal amplitude.
- the differential pair tube outputs differential electrical signals having different magnitudes.
- FIG. 9 is a timing diagram of signals at each node when the photosensitive pixel 22 of FIG. 8 performs light sensing, wherein Vp is a negative voltage of the photodiode D1 and a voltage signal on the first plate of the first capacitor c1; It is a voltage signal on the first plate of the second capacitor c2; Ip is a current signal output from the fourteenth transmission electrode S14 of the seventh transistor T7, and In is a current signal output from the sixteenth transmission electrode S16 of the eighth transistor T8.
- the first scan driving signal is input through the first input terminal In1', and the fourth transistor T4 and the fifth transistor T5 are turned on according to the high level signal.
- the reference signal Vref is transmitted to the negative electrode of the photodiode D1 and the first plate of the first capacitor c1 via the seventh transfer electrode S7 and the eighth transfer electrode S8. Since the photodiode D1 has an equivalent capacitance inside, the reference signal Verf charges the equivalent capacitance inside the photodiode D1, so that the voltage Vp on the cathode of the photodiode D1 gradually rises and reaches the voltage value of the reference signal Vref. constant. In addition, the reference signal Vref also charges the first capacitor c1 such that the voltage on the first plate of the first capacitor c1 gradually rises and remains unchanged after reaching the voltage value of the reference signal Vref.
- the reference signal Vref is transmitted to the first plate of the second capacitor c2 via the ninth transfer electrode S9 and the tenth transfer electrode S10, thereby charging the second capacitor c2, and the second capacitor c2
- the voltage Vn on the second plate gradually rises and remains unchanged after reaching the voltage value of the reference signal Vref.
- the first scan driving signal is switched from the high level signal to the low level signal, so that the first input terminal In1 becomes a low level signal, and the fourth transistor T4 and the fifth transistor T5 are both turned off.
- the fourth transistor T4 is turned off, a discharge circuit is formed between the equivalent capacitance and the first capacitor c1 and the photodiode D1.
- the photosensitive unit 222' starts performing light sensing.
- a current signal proportional to the optical signal is generated inside the photodiode D1, and thus the voltage Vp on the negative electrode of the photodiode D1 gradually decreases.
- the stronger the optical signal the faster the voltage Vp is lowered.
- the fifth transistor T5 is turned off, since the second capacitor c2 cannot form a discharge loop, the voltage Vn on the first plate of the second capacitor c2 remains unchanged.
- the output control signal is input through the second input terminal In2', the sixth transistor T6 is turned on according to the high level signal, and the constant current signal Is is transmitted to the conversion circuit 2231.
- the conversion circuit 2231 outputs two current signals having different amplitudes in accordance with the voltage difference between the voltage Vp and the voltage Vn. As the voltage Vp decreases, the voltage difference between the voltage Vn and the voltage Vp becomes larger and larger, so that the differential pair tube outputs two current signals of different amplitudes. As shown in FIG. 9, the amplitude of the current signal Ip outputted by the first output terminal Out1' decreases as the voltage Vp decreases.
- the amplitude of the current signal In outputted by the second output terminal Out2 is low.
- the level gradually rises to a current value corresponding to the voltage Vn and then rises as the current signal Ip decreases.
- the electrical signal output is doubled compared to the one electrical signal, thereby achieving signal amplification.
- the output control signal is converted from a high level signal to a low level signal, so that the second input terminal In2' becomes a low level signal, the sixth transistor T6 is turned off, the first output terminal Out1' and the second output terminal Out2 stops outputting an electrical signal and becomes a low level signal.
- the above-mentioned time t4 and time t3 are defined as a second predetermined time ⁇ t1, during which the corresponding current signal is obtained from the first output terminal Out1' and the second output terminal Out2, and according to the two current signals.
- the size of the photosensitive signal generated by the photosensitive unit 222' to perform light sensing can be obtained, thereby generating biometric information of the target object.
- the second predetermined time ⁇ t1 may be a fixed value or a change value. Since the optical signal received by the photodiode D1 is larger, the rate of decrease of the voltage Vp is faster. Therefore, in order to achieve accurate and efficient acquisition of the photosensitive signal, the magnitude of ⁇ t1 is adjusted according to the intensity of the received optical signal. Specifically, the greater the intensity of the optical signal, the shorter ⁇ t1; the smaller the intensity of the optical signal, the longer ⁇ t1.
- the interval between the above time t3 and the time t2 cannot be too long or too short to ensure that the photosensitive signal is outputted in time and efficiently. Because at time t2, the photosensitive unit 222' starts to perform light sensing, and a corresponding electrical signal is generated. If the interval time is too long, the photosensitive signal may be output in time. If the interval time is too short, the photosensitive unit 222' may generate an effective photosensitive signal in the future. The electric signal generated by the photosensitive unit 222' can be controlled to be outputted in time and efficiently.
- the photosensitive pixel 22 of the embodiment of the present invention can ensure the timely and effective output of the photosensitive signal by the output control of the photosensitive signal, and the current signal generated by the photosensitive unit 222 performing the light sensing by the conversion circuit 2231 is two differential signals.
- the mode is output, thereby realizing the amplification of the electrical signal, and improving the sensing accuracy of the photosensitive device 20.
- the two differential signals are current signals, the output of the relative voltage signal improves the anti-interference ability of the signal, and further improves the sensing accuracy of the photosensitive device 20.
- FIG. 10 illustrates a connection structure between a photosensitive pixel and a scan line, a data line, and a signal reference line in the photosensitive device according to another embodiment of the present invention, and the photosensitive pixel is shown in FIG.
- the circuit structure The photosensitive device 20 further includes a scan line group, a data line group, and a signal reference line group electrically connected to the plurality of photosensitive pixels 22.
- the scan line group includes a first scan line group composed of a plurality of first scan lines and a second scan line group composed of a plurality of second scan lines
- the data line group includes a plurality of first data lines and a plurality of strips.
- Two data lines, a plurality of third data lines, and the signal reference line group includes a plurality of signal reference lines.
- the photosensitive array 201 in FIG. 1 As an example, in the photosensitive array 201, one row of photosensitive pixels in the X direction includes n photosensitive pixels 22 arranged at intervals, and one column of photosensitive pixels in the Y direction includes m photosensitive pixels 22 arranged at intervals. Therefore, the photosensitive array 201 includes a total of m*n photosensitive pixels. The number of scanning line groups, data line groups, and signal reference line groups connected to the photosensitive pixels 22 is set correspondingly.
- the first scan line group includes m first scan lines and m second scan lines, and the m first scan lines are arranged along the Y direction, for example, G11, G12, . . . G1m, the m second The scan lines are also arranged in the Y direction, for example, G21, G22, ... G2m.
- the signal reference line group includes m signal reference lines, and the m signal reference lines are arranged in the Y direction, for example, L1, L2, ..., Lm.
- the data line group includes n first data lines, n second data lines, and n third data lines, and the n first data lines are arranged along the X direction, for example, S11, S12, ..., S1n;
- the second data lines are also arranged in the X direction, for example, S21, S22, ..., S2n;
- the n third data lines are also arranged in the X direction, for example, S31, S32, ..., S3n.
- the scan line group, the data line group, and the signal reference line group of the photosensitive device 20 may also be distributed in other regular manners or in an irregular manner.
- the first scan line, the second scan line, the signal reference line, and the first data line, the second data line, and the third data line are all electrically conductive, the lines in the intersecting position are isolated by an insulating material. .
- the m first scan lines are connected to the first input end In1 ′ of the plurality of photosensitive pixels 22
- the m second scan lines are connected to the second input end In 2 ′ of the plurality of photosensitive pixels 22
- m signals are connected.
- the reference line is connected to the third input end In3 ′ of the plurality of photosensitive pixels 22
- the n first data lines are correspondingly connected to the first output end Out1 ′ of the plurality of photosensitive pixels 22
- the n second data lines are corresponding to the plurality of
- the second output terminal Out2 of the photosensitive pixel 22 is connected
- the third data line is connected to the fourth input terminal In4 of the photosensitive pixel 22.
- the first scan line, the second scan line, and the signal reference line are all drawn from the X direction, and the first data line and the second data line are taken out from the Y direction.
- the photosensitive device 20 further includes a photosensitive driving circuit for sequentially driving the plurality of photosensitive pixels to perform light sensing; and after the photosensitive pixels start performing light sensing, controlling the photosensitive The electrical signal output generated when the pixel performs light sensing.
- the photosensitive driving circuit includes a photosensitive driving unit 24, and the first scanning line, the second scanning line, and the signal reference line in the photosensitive device 20 are both connected to the photosensitive driving unit 24.
- FIG. 11 shows a functional module of a photosensitive driving unit according to an embodiment of the present invention.
- the photosensitive driving unit 24 includes a first driving circuit 241' that supplies a first scan driving signal, a second driving circuit 242' that provides an output control signal, and a reference circuit 243' that supplies a reference signal Vref.
- the circuits of the photosensitive driving unit 24 can be integrated into one control chip through a silicon process. Of course, the circuits of the photosensitive driving unit 24 can also be formed separately in different control chips.
- the first driving circuit 241' and the second driving circuit 242' are formed on the same substrate together with the photosensitive pixels 22, and the reference circuit 243' passes through a plurality of signals of the photosensitive device 20 through a connecting member (for example, a flexible circuit board). Reference line connection.
- the reference circuit 243' is for providing a reference signal Vref that passes through a third switch of the photosensitive pixel 22 (eg, the fourth transistor T4 in the switching unit 221' shown in FIG. 8)
- the first branch circuit 2221 of the photosensitive unit 222' is selectively electrically connected.
- the third switch is closed, the reference signal Vref is transmitted to the first branch circuit 2221 of the corresponding photosensitive unit 222' through the closed third switch.
- the reference circuit 243' is further selectively connected to the second branch of the photosensitive unit 222' through a fourth switch of the photosensitive pixel 22 (for example, the fifth transistor T5 in the switching unit 221' shown in FIG. 8).
- Circuit 2222 is electrically connected.
- the fourth switch is closed, the reference signal Vref is transmitted to the second branch circuit 2222 of the corresponding photosensitive unit 222' through the closed fourth switch.
- the first driving circuit 241 ′ is electrically connected to the first scan line of the photosensitive device 20 for providing a first scan driving signal to the third switch and the fourth switch of the plurality of photosensitive pixels 22 row by row or interlaced to
- the third switch and the fourth switch are controlled to be closed, and when the first predetermined time arrives, the third switch and the fourth switch are controlled to be turned off, thereby driving the photosensitive unit 222' to start performing light sensing.
- the second driving circuit 242 ′ is electrically connected to the second scan line of the photosensitive device 20 for performing the light sensing after the driving of the photosensitive unit 222 ′, for example, the third switch and the fourth switch are turned off and reach the fourth predetermined time. (t3-t2 shown in FIG. 9), an output control signal is supplied to the fifth switch (for example, the sixth transistor T6 in the signal output unit 223' shown in FIG. 8) to control the fifth switch to be closed, and When the predetermined time arrives, the fifth switch is turned off, so that the conversion circuit 2231 converts the constant current signal into two different current signals according to the electric signal generated when the photosensitive unit 222' performs light sensing, and outputs it.
- the fifth switch for example, the sixth transistor T6 in the signal output unit 223' shown in FIG. 8
- the manner in which the first driving circuit 241 ′ controls the plurality of photosensitive pixels 22 is the same as the manner in which the first driving circuit 241 controls the plurality of photosensitive pixels 22 . That is, the first scan driving signal is supplied to the photosensitive pixel of the current line, and the output control signal is supplied to the photosensitive pixel of the current line to control the electrical signal generated when the photosensitive pixel of the current line performs light sensing.
- the first scan driving signal is further supplied to the photosensitive pixels of the next row, thereby realizing the progressive sensing of the photosensitive pixels 22, and reading out line by line; or, providing the first scanning driving signal to the photosensitive pixels of the current line and
- the predetermined time is at least one clock cycle, thereby achieving rolling sensitivity of the photosensitive pixels 22, and reading out line by line.
- the photosensitive drive circuit further includes a signal processing unit 25, and the data line groups in the photosensitive device 20 shown in FIG. 10 are all connected to the signal processing unit 25.
- the third data line is connected, for example, to a constant current source (not shown) for providing a constant current signal; the first data line and the second data line are connected, for example, to a signal processing circuit (FIG. Not shown).
- the signal processing unit 25 can also be integrated with the photosensitive driving unit 24 in one processing chip.
- the signal processing unit 25 is configured to read an electrical signal generated when the photosensitive unit 222' performs light sensing, and obtain predetermined biometric information of a target object contacting or approaching the photosensitive device according to the read electrical signal. .
- the signal processing unit 25 can be integrated in a detection chip by a silicon process. It can be understood that, in order to collect an accurate and effective electrical signal, the signal processing unit 25 can perform multiple readings on the electrical signal generated when the photosensitive unit 222' performs light sensing for a second predetermined time.
- the signal processing unit 25 includes a plurality of processing channels.
- each processing channel is connected to a first data line and a second data line.
- at least two first data lines and at least two second data lines may be connected to each processing channel, and one first data line and one piece are selected to be read each time by means of time division multiplexing.
- An electrical signal on the second data line, then another electrical signal on the first data line and the second data line, and so on, until all electrical signals on the first data line and the second data line are read take. In this way, the number of processing channels can be reduced, thereby saving the cost of the photosensitive device 20.
- FIG. 12 illustrates the structure of a photosensitive device according to another embodiment of the present invention.
- the photosensitive device 20 further includes a photosensitive panel 200.
- the photosensitive panel 200 further includes a substrate 26 on which a plurality of photosensitive pixels 22 are disposed.
- the photosensitive pixels 22 are distributed in an array.
- the photosensitive driving circuit is configured to drive the plurality of photosensitive pixels to perform light sensing, and control an electrical signal output generated when the photosensitive pixel performs light sensing.
- the photosensitive pixel 22 When the photosensitive pixel 22 performs light sensing, it is used to receive the above-mentioned optical signal, and convert the received optical signal into a corresponding electrical signal, so that the photosensitive regions of the plurality of photosensitive pixels 22 define the sensing region 203, and the sense The area other than the measurement area 203 is the non-sensing area 202.
- the non-sensing area 202 is used to set a driving circuit required for the photosensitive pixel 22 to perform light sensing, such as the above-described photosensitive driving circuit.
- the non-sensing area 202 is used to set a line bonding area to which the power supply connector is connected. For example, taking the photosensitive driving circuit shown in FIG.
- the first driving circuit 241' and the second driving circuit 242' and the reference circuit 243' are both formed on the substrate 26.
- the first driving circuit 241 ′, the second driving circuit 242 ′, and the reference circuit 243 ′ are electrically connected to the photosensitive pixels 22 through electrical connectors (eg, flexible circuit boards).
- the signal processing unit 25 described above can be selectively formed on the substrate 26 depending on the type of the substrate 26, or can be selectively electrically connected to the photosensitive pixel 22, for example, by an electrical connector (eg, a flexible circuit board).
- an electrical connector eg, a flexible circuit board
- the signal processing unit 25 may be selectively formed on the substrate 26, or may be electrically connected to the photosensitive pixel 22, for example, by a flexible circuit board; when the substrate 26 is an insulating substrate The signal processing unit 25 then needs to be electrically connected to the photosensitive pixels 22, for example, via a flexible circuit board.
- the photosensitive device 20 is a photosensitive chip for sensing biometric information of a target object that contacts or approaches the photosensitive device 20.
- the photosensitive device 20 is a fingerprint sensing chip for sensing a fingerprint image of a user's finger.
- FIG. 13 illustrates specific steps of a light sensing method of a photosensitive device according to an embodiment of the present invention.
- the light sensing method of the photosensitive device includes the following steps:
- Step S21 sequentially providing a first scan driving signal to the plurality of photosensitive pixels, so that the photosensitive pixels start to perform light sensing when the first predetermined time arrives;
- Step S22 after the photosensitive pixel starts performing light sensing, providing an output control signal to the plurality of photosensitive pixels, and controlling an electrical signal output generated when the photosensitive pixel performs light sensing.
- step S21 may specifically include: providing the first scan driving signal to the plurality of photosensitive pixels in a row or interlace driving to drive the photosensitive pixels to perform light sensing. This makes it possible to drive a row of photosensitive pixels at a time to perform light sensing, thereby speeding up the sensing speed.
- step S21 is specifically: sequentially providing a first scan driving signal to the first switch of the plurality of photosensitive pixels 22 (for example, FIG. 2
- the first transistor T1) in the illustrated switching unit 221 controls the first switch to be closed, and when the first predetermined time arrives, controls the first switch to be turned off, thereby driving the photosensitive unit 222 to start performing light sensing.
- Step S22 is specifically: after the first switch of the switch unit 221 is turned off, providing a second switch for outputting a control signal to the plurality of photosensitive pixels 22 (for example, the second transistor T2 in the signal output unit 223 shown in FIG. 2)
- the second switch is controlled to be closed so that the photosensitive unit 222 performs an electrical signal output generated when the light is sensed.
- step S11 is specifically: sequentially providing a first scan driving signal to a third switch of the plurality of photosensitive pixels 22 (for example, as shown in FIG. a fourth transistor T4) in the switching unit 221' and a fourth switch (for example, the fifth transistor T5 in the switching unit 221' shown in FIG. 8) to control the third switch and the fourth switch to be closed, and in the When a predetermined time arrives, the third switch and the fourth switch are controlled to be turned off, thereby driving the photosensitive unit 222' to start performing light sensing.
- a third switch of the plurality of photosensitive pixels 22 for example, as shown in FIG. a fourth transistor T4
- a fourth switch for example, the fifth transistor T5 in the switching unit 221' shown in FIG. 8
- Step S22 is specifically: when the third switch and the fourth switch are turned off and reach the fourth predetermined time (t3-t2 shown in FIG. 9), the output control signal is provided to the fifth switch (for example, the signal output unit shown in FIG. 8)
- the sixth transistor T6) of 223' is configured to control the fifth switch to be closed, and when the second predetermined time is reached, control the fifth switch to be turned off, so that the conversion circuit 2231 performs electricity generated when the light sensing is performed according to the photosensitive unit 222'
- the signal converts the constant current signal into two different current signals and outputs them.
- the step S21 further includes: providing the first scan driving signal to the photosensitive pixel of the current row, and providing the output control signal to the photosensitive pixel of the current row to control the After the photosensitive pixels of the current row perform the electrical signal output generated during the light sensing, the first scan driving signal is supplied to the photosensitive pixels of the next row.
- the photosensitive pixels of the next row herein are not limited to one row of photosensitive pixels adjacent to the photosensitive pixels of the current row, and may also be referred to as interlaced photosensitive pixels.
- the photosensitive device performs light sensing in a line-by-line sensing manner by progressive sensing.
- time t 1 a first scan driving signal to the sensing pixels in the first row, the first row to drive the photosensitive pixels perform light sensing
- t 2 time provides an output control signal to the photosensitive pixels of the first row, in order to control the first photosensitive photosensitive pixel output signal line
- t 3 time providing the photosensitive pixels of the first scan driving signal to the second row, the second row to drive the photosensitive pixels perform light sensing
- t 4 time provides an output control signal to the second line Sensing pixel to control the photosensitive signal output of the second row of the photosensitive signal...
- t 2m-1 providing the first scan driving signal to the photosensitive pixel of the mth row to drive the mth row of photosensitive pixels to perform light sensing
- an output control signal is supplied to the photosensitive pixels of the mth line to control the photosensitive pixels of the mth line to output a photosensitive signal.
- the photosensitive device in the embodiment of the present invention performs light sensing
- the photosensitive pixels of the current row perform light sensing
- the photosensitive signals generated when performing the light sensing are read
- the photosensitive pixels of the next row are executed.
- the sensing is such that the reading of the photosensitive signals of each row of photosensitive pixels does not interfere with each other, so that an accurate photosensitive signal can be obtained.
- the photosensitive device since the photosensitive device takes a long time to perform one light sensing, it can be used as a test mode.
- the step S21 further includes: providing the first scan driving signal to the photosensitive pixels of the next row when the first scan driving signal is supplied to the photosensitive pixels of the current row for a predetermined time
- the predetermined time is at least one clock cycle.
- the photosensitive signals in the photosensitive pixels 22 are output through the control of the output control signals, the light sensing times of the photosensitive pixels of different rows may overlap, that is, when the photosensitive pixels of the current row perform light sensing, the first scan may be provided.
- the driving signal is sent to the photosensitive pixel of the next row to drive the photosensitive pixel to perform light sensing.
- the photosensitive pixels of the next row herein are not limited to one row of photosensitive pixels adjacent to the photosensitive pixels of the current row, and may also be referred to as interlaced photosensitive pixels.
- the photosensitive device performs light sensing by means of roll sensing, which is read out line by line.
- time t 11 a first scan driving signal to the sensing pixels in the first row, the first row to drive the photosensitive pixels perform light sensing
- t 12 time providing a first driving signal to the scan line of the photosensitive pixel 2
- t 13 time providing a first driving signal to the scanning line 3 of the photosensitive pixel, to drive the third row of pixels perform light sensing photosensitive
- t 1m time providing a first A scan driving signal is applied to the photosensitive pixels of the mth row to drive the mth row of photosensitive pixels to perform light sensing.
- an output control signal is supplied to the photosensitive pixels of the row.
- t 21 time provides an output control signal to the photosensitive pixels of the first row, in order to control the photosensitive signal output line of the first photosensitive pixels
- t 22 time supplied to the second row of the photosensitive pixel outputs a control signal to control the second row of the photosensitive The photosensitive signal output of the pixel.
- the time required for the photosensitive device 20 to perform the light sensing is short, and the time for all the photosensitive pixels to wait for reading the photosensitive signal is also the same, that is, the influence of the charge leakage on the photosensitive signal collection is solved, thereby improving the effect. Sensing accuracy.
- FIG. 14 shows a structure of an electronic device according to an embodiment of the present invention
- FIG. 15 shows a cross-sectional structure of the electronic device shown in FIG. 14 along line II
- FIG. 15 only A partial structure of the electronic device is shown.
- the electronic device includes the photosensitive device of any of the above embodiments, which is used for image display of an electronic device and for sensing biometric information of a target object contacting or approaching the electronic device.
- Electronic devices such as, but not limited to, suitable types of electronic products such as consumer electronics, home electronics, vehicle-mounted electronic products, and financial terminal products.
- consumer electronic products such as mobile phones, tablets, notebook computers, desktop monitors, computer integrated machines.
- Home-based electronic products such as smart door locks, TVs, refrigerators, wearable devices, etc.
- Vehicle-mounted electronic products such as car navigation systems, car DVDs, etc.
- Financial terminal products such as ATM machines, terminals for self-service business, etc.
- the electronic device shown in FIG. 14 is exemplified by a mobile terminal of the mobile phone type.
- the above-described bio-sensing module can also be applied to other suitable electronic products, and is not limited to mobile terminals.
- a display device (not shown) is disposed on the front surface of the mobile terminal 3, and the display device includes a display panel 300.
- the protective cover 400 is disposed above the display panel 300.
- the screen of the display panel 300 is relatively high, for example, 80% or more.
- the screen ratio refers to the ratio of the display area 305 of the display panel 300 to the front area of the mobile terminal 3.
- the photosensitive panel 200 is a panel structure that is adapted to the display panel 300 and is disposed below the display panel 300 . If the display panel 300 is in the form of a flexible curved surface, the photosensitive panel 200 is also in the form of a flexible curved surface. Therefore, the photosensitive panel 200 not only has a planar structure but also a curved surface structure. In this way, the lamination of the photosensitive panel 200 and the display panel 300 is facilitated.
- the display panel 300 Since the photosensitive panel 200 is located below the display panel 300, the display panel 300 has a light-transmitting region through which an optical signal reflected from the target object passes, so that the photosensitive panel 200 can receive the optical signal passing through the display panel 300 and receive The incoming optical signal is converted into an electrical signal, and predetermined biometric information of the target object contacting or approaching the electronic device is acquired according to the converted electrical signal.
- the electronic device not only has the effect of the photosensitive device 20 described in the above embodiment, but also utilizes the optical signal emitted by the display panel 300 to realize the biometric information sensing of the target object, without additionally setting a light source.
- This not only saves the cost of the electronic device, but also enables biometric information sensing of the target object within the display area 305 of the touch or touch display panel 300.
- the photosensitive device 20 can be independently fabricated, and then assembled with an electronic device, thereby accelerating the preparation of the electronic device.
- the display panel 300 emits an optical signal.
- the photosensitive device 20 receives the optical signal reflected by the object, converts the received optical signal into a corresponding electrical signal, and acquires predetermined biometric information of the object according to the electrical signal. For example, fingerprint image information.
- the photosensitive device 20 can realize sensing of a target object that contacts or approaches an arbitrary position of the display area.
- the display panel 300 is, for example but not limited to, an OLED display device, as long as the display device capable of realizing the display effect and having a light-transmitting region through which the optical signal passes is within the scope of the present invention.
- the display panel 300 can be a bottom emission structure, a top emission structure, and a double-sided light transmission structure.
- the display screen can be a rigid screen of a rigid material or a flexible screen of a flexible material.
- the photosensitive panel 200 is configured to perform biometric information sensing of a target object at any position within the display area of the display panel 300.
- the display panel 300 has a display area 305 and a non-display area 306 defined by the light-emitting areas of all the display pixels 32 of the display panel 300.
- the area other than the display area 305 is a non-display area 306 for setting a circuit such as a display driving circuit for driving the display pixels 32 or a line bonding area for connecting the flexible circuit boards.
- the photosensitive panel 200 has a sensing area 203 and a non-sensing area 204 defined by the sensing areas of all the photosensitive pixels 22 of the photosensitive panel 200, and the area other than the sensing area 203 is the non-sensing area 204.
- the non-sensing area 204 is for setting a circuit such as the photosensitive driving unit 24 that drives the photosensitive pixel 22 to perform light sensing or a line bonding area for connecting the flexible circuit board.
- the shape of the sensing region 203 is consistent with the shape of the display region 305, and the size of the sensing region 203 is greater than or equal to the size of the display region 305, such that the photosensitive panel 200 can be placed at any position adjacent to or adjacent to the display region 305 of the display panel 300. Sensing of predetermined biometric information of the target object. Further, the area of the photosensitive panel 200 is less than or equal to the area of the display panel 300, and the shape of the photosensitive panel 200 is consistent with the shape of the display panel 300, so that the assembly of the photosensitive panel 200 and the display panel 300 is facilitated. However, in some embodiments, the area of the photosensitive panel 200 may also be larger than the area of the display panel 300.
- the sensing area 203 of the photosensitive panel 200 may also be smaller than the display area 305 of the display panel 300 to achieve the sense of predetermined biometric information of the target object of the display area 300 displaying the local area of the area 305. Measurement.
- the display device is further configured to perform touch sensing, and after the display device detects the touch or proximity of the target object, the control display panel emits light corresponding to the position of the touch region.
- FIG. 17 shows the structure of an electronic device according to an embodiment of the present invention
- FIG. 18 shows the electronic device shown in FIG. The cross-sectional structure along the line II-II
- FIG. 18 shows only a partial structure of the electronic device.
- the photosensitive module of the embodiment of the present invention is applied to a mobile terminal 3, and a display panel 300 is disposed on the front surface of the mobile terminal, and a protective cover 400 is disposed above the display panel 300.
- the screen of the display panel 300 is relatively high, for example, 80% or more.
- the screen ratio refers to the ratio of the actual display area 305 of the display panel 300 to the front area of the mobile terminal.
- a bio-sensing area S for the target object to touch is provided at a mid-lower position of the actual display area 305 of the display panel 300 to perform biometric information sensing of the target object, for example, the target object is a finger, and the bio-sensing area is S is a fingerprint recognition area for fingerprint recognition.
- a photosensitive device 20 is disposed at a position corresponding to the fingerprint recognition area S below the display panel 300, and the photosensitive device 20 is configured to acquire a fingerprint image of the finger when the finger is placed on the fingerprint recognition area S.
- the middle and lower positions of the display panel 300 are for the convenience of the finger to touch the position of the display panel 300 when the user holds the mobile terminal. Of course, it can also be placed at other locations that are convenient for finger touch.
- the electronic device further includes a touch sensor (not shown) by which the touch area of the target object on the protective cover 400 can be determined.
- the touch sensor adopts capacitive touch sensing technology, and of course, other methods, such as resistive touch sensing, pressure sensitive touch sensing, and the like.
- the touch sensor is configured to determine a touch area of the target object when a target object contacts the protective cover 400 to drive a display pixel corresponding to the touch area to light and the photosensitive pixel to perform light sensing.
- the touch sensor is either integrated with the protective cover 400, or integrated with the photosensitive panel 200, or integrated with the display panel 300.
- the integrated touch sensor not only realizes the touch detection of the target object, but also reduces the thickness of the electronic device, which is beneficial to the development of the electronic device in the direction of thinning and thinning.
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Abstract
一种感光驱动电路、感光装置(20)及电子设备,感光驱动电路用于依次驱动多个感光像素(22)执行光感测;在感光像素(22)开始执行光感测后,控制感光像素(22)执行光感测时产生的电信号输出。感光装置(20)包括多个感光像素(22)及上述感光驱动电路,电子设备包括该感光装置(20)。
Description
本实用新型涉及一种用于感测生物特征信息的感光驱动电路及感光装置、电子设备。
目前,指纹识别,已逐渐成为移动终端等电子产品的标配组件。由于光学式指纹识别比电容式指纹识别具有更强的穿透能力,因此光学式指纹识别应用于移动终端是未来的发展趋势。然,应用于移动终端的现有光学式指纹识别结构仍有待改进。
实用新型内容
本实用新型实施方式旨在至少解决现有技术中存在的技术问题之一。为此,本实用新型实施方式需要提供一种感光驱动电路、感光装置及电子设备。
本实用新型实施方式的一种感光驱动电路,用于依次驱动所述多个感光像素执行光感测;在所述感光像素开始执行光感测后,控制该感光像素执行光感测时产生的电信号输出。
本实用新型实施方式的光感测方法,不但可以控制感光像素光感测时间,而且还通过输出控制信号实现了感光单元产生的电信号及时、有效地输出,从而提高了感测精度。另外,通过输出控制信号控制感光像素的感光信号的输出,使得感光像素与输出端的信号隔离,避免其他的电路负载影响感光像素的感光信号,从而获得准确的感光信号,进一步提高了感测精度。
在某些实施方式中,所述多个感光像素呈阵列分布于一基底上,且所述基底上还设有多条分别与所述多个感光像素电性连接的第一扫描线;所述感光驱动电路包括:
第一驱动电路,对应与所述第一扫描线电性连接,用于逐行或隔行提供一第一扫描驱动信号给所述多个感光像素,以驱动所述多个感光像素逐行或隔行执行光感测。
在某些实施方式中,所述第一驱动电路进一步用于:
在提供所述第一扫描驱动信号给当前行的感光像素,以及提供所述输出控制信号给该当前行的感光像素,以驱动该当前行的感光像素执行光感测,且控制执行光感测时产生的电信号输出后,再提供所述第一扫描驱动信号给下一行的感光像素。
本实用新型实施方式中的感光装置执行光感测时,在当前行的感光像素执行光感测,且执行光感测时产生的感光信号被读取之后,再进行下一行的感光像素执行光感测,如此使得每一行感光像素的感光信号的读取互不干扰,从而可以获得准确的感光信号。另外,由于感光装置执行一次光感测需要的时间较长,故而可以作为测试模式使用。
在某些实施方式中,所述第一驱动电路进一步用于:
在提供所述第一扫描驱动信号给当前行的感光像素并达到一预定时间时,提供所述第一扫描驱动信号给下一行的感光像素;所述预定时间为至少一时钟周期。
本实用新型实施方式通过感光装置滚动感光的方式,使得该感光装置执行一次光感测的时间较短,而且所有的感光像素等待读取感光信号的时间也一致,即解决了电荷泄漏对感光信号采集造成的影响,从而提高了感测精度。
在某些实施方式中,所述基底上还设有多条与所述多个感光像素电性连接的第二扫描线;所述感光驱动电路进一步包括:第二驱动电路,该第二驱动电路对应与所述第二扫描线电性连接,用于在每个感光像素开始执行光感测并达到第四预定时间时,提供所述输出控制信号给该感光像素,以控制该感光像素执行光感测时产生的电信号输出。
在某些实施方式中,所述第二驱动电路进一步用于:控制所述感光像素执行光感测时产生的电信号输出并持续第二预定时间。
在某些实施方式中,所述第二预定时间根据接收到的光信号的强度进行动态调整。
在某些实施方式中,所述接收到的光信号的强度越大,第二预定时间越短;所述接收到的光信号的强度越小,第二预定时间越长。
本实用新型实施方式根据光信号的强度及时调整感光像素产生的电信号读取时间,保证了电信号的准确读取,从而提高了感测精度。
在某些实施方式中,所述基底上还设有与所述多个感光像素电性连接的数据线;所述感光驱动电路进一步包括信号处理单元,所述信号处理单元与所述多条数据线电性连接,用于对所述感光像素输出的电信号进行读取,并根据读取的电信号获得接触或接近所述感光像素的目标物体的预定生物特征信息。
在某些实施方式中,所述感光驱动电路形成在所述基底上或者通过一电性连接件与所述多个感光像素电性连接;或者,所述感光驱动电路的一部分电路形成在所述基底上,另一部分电路通过一连接件与所述多个感光像素电性连接。
本实用新型实施方式提供的一种感光装置,包括多个感光像素以及上述任意一实施方式的感光驱动电路,该感光驱动电路用于驱动所述多个感光像素执行光感测,并在所述感光像素开始执行光感测后,控制该感光像素执行光感测时产生的电信号输出。
在某些实施方式中,所述感光装置为指纹感测装置,用于采集手指的指纹信息。
在某些实施方式中,所述感光装置为一生物感测芯片,用于获取接近或接触所述感光装置的目标物体的预定生物特征信息。
本实用新型实施方式提供的一种电子设备,包括上述任意一实施方式的感光装置。
本实用新型实施方式的附加方面和优点将在下面的描述中部分给出,部分将从下面的描述中变得明显,或通过本实用新型实施方式的实践了解到。
本实用新型实施方式的上述和/或附加的方面和优点从结合下面附图对实施方式的描述中将变得明显和容易理解,其中:
图1是本实用新型一实施方式的感光装置中感光像素的阵列分布示意图;
图2是图1所示的感光像素一实施方式的电路结构示意图;
图3是图2所示的感光像素在执行光感测时,各节点处的信号时序图;
图4是本实用新型一实施方式的感光装置中,感光像素与扫描线、数据线和信号参考线之间的连接关系结构,且该感光像素为图2示出的感光像素结构;
图5是图4所示的感光驱动单元一实施方式的结构框图;
图6是图4所示的感光装置执行光感测的一实施方式的信号时序图;
图7是图4所示的感光装置执行光感测的另一实施方式的信号时序图;
图8是图1所示的感光像素另一实施方式的电路结构示意图;
图9是图8所示的感光像素在执行光感测时,各节点处的信号时序图;
图10是本实用新型一实施方式的感光装置中,感光像素与扫描线、数据线和信号参考线之间的连接关系结构,且该感光像素为图8示出的感光像素结构;
图11是图10所示的感光驱动单元一实施方式的结构框图;
图12是本实用新型一实施方式的感光装置中感光面板的结构示意图;
图13是本实用新型一实施方式的感光装置的光感测方法的流程示意图;
图14是本实用新型一实施方式的感光装置所应用的电子设备的结构示意图;
图15是图14所示的电子设备沿I-I线的剖面示意图,且图15示出了电子设备的部分结构;
图16是本实用新型一实施方式的显示面板的显示区域与感光面板的感测区域的对应位置示意图;
图17是本实用新型一实施方式的感光装置所应用的电子设备的结构示意图;
图18是图17所示的电子设备沿II-II线的剖面示意图,且图18示出了电子设备的部分结构。
下面详细描述本实用新型的实施方式,所述实施方式的示例在附图中示出,其中自始至终相同或类似的标号表示相同或类似的元件或具有相同或类似功能的元件。下面通过参考附图描述的实施方式是示例性的,仅用于解释本实用新型,而不能理解为对本实用新型的限制。
在本实用新型的描述中,需要理解的是,术语“第一”、“第二”仅用于描述目的,而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此,限定有“第一”、“第二”的特征可以明示或者隐含地包括一个或者更多个所述特征。在本实用新型的描述中,“多个”的含义是两个或两个以上,除非另有明确具体的限定。“接触”或“触摸”包括直接接触或间接接触。
在本实用新型的描述中,需要说明的是,除非另有明确的规定和限定,术语“安装”、“相连”、“连接”应做广义理解,例如,可以是固定连接,也可以是可拆卸连接,或一体地连接;可以是机械连接,也可以是电连接或可以相互通信;可以是直接相连,也可以通过中间媒介间接相连,可以是两个元件内部的连通或两个元件的相互作用关系。对于本领域的普通技术人员而言,可以根据具体情况理解上述术语在本实用新型中的具体含义。
下文的公开提供了许多不同的实施方式或例子用来实现本实用新型的不同结构。为了简化本实用新型的公开,下文中对特定例子的部件和设定进行描述。当然,它们仅仅为示例,并且目的不在于限制本实用新型。此外,本实用新型可以在不同例子中重复参考数字和/或参考字母,这种重复是为了简化和清楚的目的,其本身不指示所讨论各种实施方式和/或设定之间的关系。此外,本实用新型提供了的各种特定的工艺和材料的例子,但是本领域普通技术人员可以意识到其他工艺的应用和/或其他材料的使用。
进一步地,所描述的特征、结构可以以任何合适的方式结合在一个或更多实施方式中。在下面的描述中,提供许多具体细节从而给出对本实用新型的实施方式的充分理解。然而,本领域技术人员应意识到,没有所述特定细节中的一个或更多,或者采用其它的结构、组元等,也可以实践本实用新型的技术方案。在其它情况下,不详细示出或描述公知结构或者操作以避免模糊本实用新型。
本实用新型实施方式提出一种设置于电子设备内的感光装置,尤其设置于电子设备的显示屏下方。该显示屏例如但不限于OLED显示面板等具有发出光信号的显示装置。电子设备工作时,显示屏发出光信号,以执行相应的图像显示。此时,若有目标物体接触或触摸该电子设备,显示屏发出的光信号到达目标物体后发生反射,反射回来的光信号穿过显示屏后被感光装置接收,感光装置将接收到的光信号转换为与光信号对应的电 信号,以根据该感光装置产生的电信号,形成目标物体的预定生物特征信息。
上述目标物体的生物特征信息例如但不限于指纹、掌纹、耳纹、脚掌等皮肤纹路信息,以及心率、血氧浓度、静脉等其他生物特征信息。目标物体例如但不限于人体,也可以为其他合适类型的物体。
在某些实施方式中,该电子设备也可以设置用于生物特征信息感测的光源。当该电子设备执行生物特征信息感测时,该光源发出相应的光信号,例如红外光,从而实现对目标物体的心率、血氧浓度、静脉等信息的感测。
电子设备例如但不局限为消费性电子产品、家居式电子产品、车载式电子产品、金融终端产品等合适类型的电子产品。其中,消费性电子产品如为手机、平板电脑、笔记本电脑、桌面显示器、电脑一体机等。家居式电子产品如为智能门锁、电视、冰箱、穿戴式设备等。车载式电子产品如为车载导航仪、车载DVD等。金融终端产品如为ATM机、自助办理业务的终端等。
请参照图1,图1示出了一感光装置中感光像素的阵列分布结构,该感光装置20包括多个感光像素22,该多个感光像素22按行列方式进行阵列分布,以形成感光阵列201。具体地,该感光阵列201包括多行感光像素和多列感光像素,每行感光像素沿X方向间隔分布,每列感光像素沿Y方向间隔分布。在感光装置20进行图像感测时,可以从X方向上逐行驱动各行感光像素22执行光感测,再从Y方向上读取各感光像素22执行光感测而产生的电信号。当然,形成感光阵列201的各感光像素22不限于图1示出的垂直关系,另外也可以为其他规则方式分布或非规则方式分布。
在某些实施方式中,每一感光像素22均包括传感单元和信号输出单元。其中,所述传感单元用于接收光感测控制信号,在接收到光感测控制信号时,执行光感测。在执行光感测时,所述传感单元接收光信号,并将接收到的光信号转换为相应的感光信号,即电信号;所述信号输出单元用于接收输出控制信号,并在接收到所述输出控制信号时,将所述传感单元执行光感测时产生的感光信号输出。
具体地,参照图2,图2示出了图1中一个感光像素22的一种电路结构。因此,该感光像素22也可称为感光电路。本实用新型实施方式中的一感光像素22具有第一输入端In1、第二输入端In2、第三输入端In3,以及一第一输出端Out1。光感测控制信号包括第一扫描驱动信号。感光像素22包括传感单元和信号输出单元223,传感单元又包括开关单元221和感光单元222,感光单元222连接在开关单元221和信号输出单元223之间。开关单元221通过第三输入端In3接收一参考信号Vref,另外,开关单元221还通过第一输入端In1接收一第一扫描驱动信号,并在接收到第一扫描驱动信号时将参考 信号Vref传输至感光单元222,以驱动感光单元222工作。感光单元222用于接收光信号,并在接收到光信号时将接收到的光信号转换为相应的电信号。信号输出单元223通过第二输入端In2接收输出控制信号,并根据输出控制信号将感光单元222产生的电信号从第一输出端Out1输出。
可选地,上述第一扫描驱动信号和输出控制信号均为一脉冲信号,且第一扫描驱动信号中高电平的持续时间为第一预定时间,输出控制信号中高电平的持续时间为第二预定时间。
在某些实施方式中,感光单元222包括一感光器件,该感光器件包括一第一电极和第二电极,第一电极用于接收开关单元221传输过来的参考信号Vref,第二电极用于接收一固定电信号。通过参考信号Vref和固定电信号施加于感光器件的两电极,形成驱动感光器件的驱动电压。该感光器件例如但不限于光电二极管D1,可变更地,该感光器件还可以为光电阻、光敏三极管、薄膜晶体管等等。需要说明的是,感光器件的数量也可以为2个、3个等等。以光电二极管D1为例,该光电二极管D1包括正极和负极,其中正极接收一预定电信号,例如接地信号NGND;负极作为感光器件的第一电极,用于接收开关单元221传输过来的参考信号Vref。需要说明的是,只要参考信号Vref与该预定信号对应施加在光电二极管D1的两端时,能使光电二极管D1两端形成反向电压,从而驱动光电二极管D1执行光感测即可。
当开关单元221闭合时,该参考信号Vref通过闭合的开关单元221传输至光电二极管D1的负极,由于光电二极管D1内部具有一等效电容,因此参考信号Verf对光电二极管D1内部的等效电容进行充电,从而使得光电二极管D1的负极上的电压Vg逐渐上升并在第一预定时间到达时,电压Vg达到参考信号Vref的电压值并保持不变。此时,光电二极管D1两端的电压差将达到驱动光电二极管工作的反向电压,即光电二极管D1处于工作状态。由于第一扫描驱动信号在第一预定时间到达时,由高电平信号转为低电平信号,开关单元221根据低电平信号断开,则光电二极管D1内部形成放电回路。此时,若有光信号照射到该光电二极管D1,光电二极管D1的反向电流迅速增大,从而光电二极管D1的负极节点上的电压Vg随之发生变化,即逐渐下降。而且,由于光信号的强度越大,光电二极管D1产生的反向电流也越大,则光电二极管D1的负极节点上的电压Vg的下降速度越快。
进一步地,感光单元222还包括第一电容c1。该第一电容c1用于执行光感测时,与感光器件形成放电回路,以获得相应的感光信号。具体地,如图2所示,该第一电容c1与感光器件并联设置,即第一电容c1的第一极板与光电二极管D1的负极连接,第 一电容c1的第二极板接一预定电信号,例如地信号NGND。在参考信号Vref传输至光电二极管D1的负极时,也对第一电容c1进行充电,且在开关单元221断开时,第一电容c1与光电二极管D1形成放电回路,且第一电容c1的第一极板的电压(即电压Vg)也逐渐下降。通过设置第一电容c1,增大了感光单元222的电容容量,从而降低光电二极管D1负极上的电压下降速度,可以保证获取到有效的感光信号,提高了感光装置20对目标物体的感测精度。
进一步地,上述第一电容c1为可变电容,例如由多个电容形成的电容阵列,且该多个电容并联设置,通过控制该多个电容是否接入来实现第一电容c1的容量变化。由于第一电容c1设置为可变电容,因此通过该第一电容c1的容量调整,适应接收到的光信号的变化,从而获得准确、有效的感光信号。具体地,若接收到的光信号的强度越大,则第一电容c1的容量越大,若接收到的光信号的强度越小,则第一电容c1的容量越小。
在某些实施方式中,开关单元221包括一第一晶体管T1,该第一晶体管T1例如但不限于三极管、MOS管、薄膜晶体管中的任意一个或几个。以MOS管为例,该第一晶体管T1包括第一控制电极C1、第一传输电极S1和第二传输电极S2,其中第一控制电极为MOS管的栅极,第一传输电极S1为MOS管的漏极,第二传输电极S2为MOS管的源极。第一控制电极C1与第一输入端In1连接,用于接收第一扫描驱动信号;第一传输电极S1与第三输入端In3连接,用于接收参考信号Vref;第二传输电极S2与感光单元222中光电二极管D1的负极连接。当通过第一输入端In1输入第一扫描驱动信号时,第一晶体管T1根据第一扫描驱动信号导通,参考信号Vref经第一传输电极S1、第二传输电极S2加载到光电二极管D1的负极以及第一电容c1的第一极板;第一晶体管T1导通并持续第一预定时间后截止,第一电容c1与光电二极管D1形成放电回路,开始执行光感测。
在某些实施方式中,信号输出单元223包括一第二晶体管T2和缓冲电路。缓冲电路用于将感光单元222产生的电信号进行缓冲。该第二晶体管T2例如但不限于三极管、MOS管、薄膜晶体管中的任意一个或几个。以MOS管为例,第二晶体管T2包括第二控制电极C2、第三传输电极S3和第四传输电极S4,其中第二控制电极C2为MOS管的栅极,第三传输电极S3为MOS管的漏极,第四传输电极S4为MOS管的源极。第二控制电极C2与第二输入端In2连接,用于接收输出控制信号;所述第三传输电极S3与所述缓冲电路连接,用于接收缓冲电路输出的电信号;第四传输电极S4与第一输出端Out1连接,用于将经过所述缓冲电路缓冲后的电信号输出。
进一步地,缓冲电路连接在感光单元222和第二晶体管T2之间,用于将所述感光 单元222转换后的电信号进行缓冲,并在第二晶体管T2导通时,输出缓冲的电信号。本实施例中,该缓冲电路包括一第三晶体管T3,该第三晶体管T3例如但不限于三极管、MOS管、薄膜晶体管中的任意一个或几个。以MOS管为例,该第三晶体管T3包括第三控制电极C3、第五传输电极S5、第六传输电极S6,其中第三控制电极C3为MOS管的栅极,第五传输电极S5为MOS管的漏极,第六传输电极S6为MOS管的源极。第三控制电极C3与光电二极管D1的负极连接,用于接收光电二极管D1执行光感测时产生的电信号;第五传输电极S5用于接收一电压信号Vcc;第六传输电极S6与第二晶体管T2的第三传输电极S3连接,用于在第二晶体管T2导通时输出缓冲的电信号。
上述第三晶体管T3中,第六传输电极S6的电压Vs随第三控制电极C3的电压Vg变化而变化,即不论第六传输电极S6连接的电路负载如何变化,都不影响第六传输电极S6的电压。而且,由于晶体管特性,电压Vs比电压Vg始终低一个阈值电压,该阈值电压为第三晶体管T3的门限电压。因此,缓冲电路起到缓冲隔离的作用,将感光单元222执行光感测时产生的电信号进行隔离,避免其他的电路负载影响感光单元222产生的感光信号,从而保证了感光像素22准确地执行光感测,提高了感光装置20对目标物体的感测精度。
请参照图3,图3示出了图2所示的感光像素22执行光感测时各节点处的信号时序,其中Vg为光电二极管D1负极上的电压,也为第三晶体管T3的第三控制电极C3上的电压;Vs为第三晶体管T3的第六传输电极S6上的电压。
t1时刻,通过第一输入端In1输入第一扫描驱动信号,使得第一晶体管T1导通并持续第一预定时间(即t2-t1)后截止,在该第一预定时间内,参考信号Vref经第一传输电极S1和第二传输电极S2传输至光电二极管D1的负极以及第一电容c1的第一极板。由于光电二极管D1内部具有一等效电容,因此参考信号Verf对光电二极管D1内部的等效电容进行充电,从而使得光电二极管D1的负极上的电压Vg逐渐上升并在达到参考信号Vref的电压值后保持不变。另外,由于第一电容c1与光电二极管D1并联,因此参考信号Vref也对第一电容c1进行充电,从而使得第一极板上的电压逐渐上升并在达到参考信号Vref的电压值后保持不变。
t2时刻,第一扫描驱动信号由高电平变为低电平信号,即第一输入端In1变为低电平信号,第一晶体管T1截止,等效电容和第一电容c1与光电二极管D1之间形成放电回路。若光电二极管D1上有光信号照射,则光电二极管D1内部产生与光信号成正比的电流信号,因此光电二极管D1负极上的电压Vg逐渐降低。而且,光信号越强,电压Vg降低的速度越快。另外,由于第三晶体管T3的电压跟随特性,第三晶体管T3的第 六传输电极S6上的电压Vs随光电二极管D1负极上的电压Vg变化而变化,而且电压Vs始终比电压Vg低Vth,该Vth为第三晶体管T3的门限电压。需要说明的是,该第一预定时间以保证感光单元22中光电二极管以及第一电容c1充电至参考信号Vref。
t3时刻,也就是感光单元222开始执行光感测并达到第四预定时间(即t3-t2)后,通过第二输入端In2输入输出控制信号,第二晶体管T2根据高电平信号导通,此时第三晶体管T3的第六传输电极S6上的电压Vs经第二晶体管T2的第三传输电极S3和第四传输电极S4,从第一输出端Out1输出。该第一输出端Out1输出的电压先从低电平逐渐上升至第六传输电极S6上的电压Vs,然后跟随第六传输电极S6上的电压Vs的变化而变化。需要说明的是,该第四预定时间为至少一个时钟周期,而且第四预定时间不能过长,当然也不能过短,以保证感光单元222执行光感测时产生的感光信号能有效且及时地输出。
t4时刻,输出控制信号由高电平信号变为低电平信号,即第二输入端In2变为低电平信号,第二晶体管T2截止,第一输出端Out1输出的电压逐渐下降或保持不变。为了保证下次信号的有效输出,该第一输出端Out1输出电压需逐渐下降至低电平。上述t4时刻与t3时刻之间这段时间,亦即第二预定时间Δt1内,第三晶体管T3的第六传输电极S6上的电压Vs(即相当于光电二极管D1负极上的电压Vg)将从第一输出端Out1输出,因此通过读取第一输出端Out1的电压信号,即可获得光电二极管D1因接收到光信号而产生的感光信号的大小,进而生成目标物体的生物特征信息。
进一步地,上述第二预定时间Δt1可以为固定值,也可以为变化值。由于光电二极管D1接收到的光信号越大,电压Vg的下降速度越快,从而电压Vs的下降速度也越快,因此,为实现感光信号的准确有效地获取,根据接收到的光信号的强度调整Δt1的大小。具体地,光信号强度越大,则第二预定时间Δt1越短;光信号强度越小,则第二预定时间Δt1越长。
在某些实施方式中,参照图4,图4示出了感光装置20中感光像素22与各扫描线、数据线以及信号参考线的连接结构,且该感光像素为图2示出的电路结构。该感光装置20进一步包括与多个感光像素22电性连接的扫描线组、数据线组、信号参考线组。其中,扫描线组包括由多条第一扫描线组成的第一扫描线组和由多条第二扫描线组成的第二扫描线组,数据线组包括多条数据线,信号参考线组包括多条信号参考线。以图1中的感光阵列201为例,感光阵列201中,X方向上一行感光像素包括间隔排列的n个感光像素22,Y方向上的一列感光像素包括间隔排列的m个感光像素22,因此该感光阵列201一共包括m*n个感光像素22。对应地,第一扫描线组包括m条第一扫描线,且 该m条第一扫描线沿Y方向间隔排列,例如G11、G12、…G1m;第二扫描线组还包括m条第二扫描线,且该m条第二扫描线也沿Y方向间隔排列,例如G21、G22、…G2m;信号参考线组包括m条信号参考线,且该m条信号参考线沿Y方向间隔排列,例如L1、L2、…Lm;数据线组包括n条数据线,且该n条数据线沿X方向间隔排列,例如S1、S2、…Sn-1、Sn。当然,感光装置20的扫描线组、数据线组和信号参考线组也可以为其他规则方式分布或非规则方式分布。另外,由于第一扫描线、第二扫描线、信号参考线和数据线具有导电性,因此处于交叉位置的第一扫描线、第二扫描线、信号参考线和数据线之间通过绝缘材料进行隔离。
具体地,m条第一扫描线对应与多个感光像素22的第一输入端In1连接,m条第二扫描线对应与多个感光像素22的第二输入端In2连接,m条信号参考线对应与多个感光像素22的第三输入端In3连接,n条数据线对应与多个感光像素22的第一输出端Out1连接。其中,为了布线方便,第一扫描线、第二扫描线、信号参考线均从X方向上引出,数据线从Y方向上引出。
在某些实施方式中,感光装置20进一步包括感光驱动电路,该感光驱动电路用于依次驱动所述多个感光像素22执行光感测;在所述感光像素22开始执行光感测后,控制该感光像素22执行光感测时产生的电信号输出。
进一步地,请继续参照图4,该感光驱动电路包括一感光驱动单元24,感光装置20中的第一扫描线、第二扫描线、信号参考线均连接至该感光驱动单元24。请参照图5,图5示出了图4中感光驱动单元24一实施方式的结构。该感光驱动单元24包括提供第一扫描驱动信号的第一驱动电路241、提供输出控制信号的第二驱动电路242和提供参考信号Vref的参考电路243。该感光驱动单元24的各电路可通过硅工艺集成在一颗控制芯片中,当然该感光驱动单元24的各电路也可以分开形成在不同的控制芯片中。例如,第一驱动电路241和第二驱动电路242与感光像素22一起形成在同一基板上,参考电路243则通过一连接件(例如,柔性电路板)与感光装置20上的多条信号参考线连接。
在某些实施方式中,参考电路243用于提供参考信号Vref,该参考电路243通过感光像素22的第一开关(例如,图2所示的开关单元221中的第一晶体管T1)可选择性地与所述感光单元222电性连接。在第一开关闭合时,该参考信号Vref则通过闭合的第一开关传输给相应的感光单元222。
第一驱动电路241与感光装置20的第一扫描线电性连接,用于逐行或隔行提供第一扫描驱动信号给感光像素22中的第一开关,以控制第一开关闭合,并在第一预定时 间到达时,控制第一开关断开,从而驱动感光单元222开始执行光感测。
第二驱动电路242与感光装置20的第二扫描线电性连接,用于在每个感光像素开始执行光感测并达到第四预定时间时,即第一开关断开并达到第四预定时间(例如,图3所示的t3-t2)时,提供输出控制信号给感光像素22中的第二开关(例如,图2所示的信号输出单元223中的第二晶体管T2),控制第二开关闭合,以使感光单元222执行光感测时产生的电信号输出。
进一步地,在某些实施方式中,第一驱动电路241进一步用于:在提供所述第一扫描驱动信号给当前行的感光像素,以及提供所述输出控制信号给该当前行的感光像素,以驱动该当前行的感光像素执行光感测,且控制该感光像素执行光感测时产生的电信号输出后,再提供所述第一扫描驱动信号给下一行的感光像素。需要说明的时,这里的下一行的感光像素不限于与当前行的感光像素相邻的一行感光像素,也可以指隔行的感光像素。
具体地,参照图6,图6示出了图4所示的感光装置执行光感测时的时序,该感光装置采用逐行感光,逐行读出的方式执行光感测。t
1时刻,提供第一扫描驱动信号给第1行的感光像素,以驱动第1行感光像素执行光感测,t
2时刻,提供输出控制信号给第1行的感光像素,以控制第1行的感光像素输出感光信号;t
3时刻,提供第一扫描驱动信号给第2行的感光像素,以驱动第2行感光像素执行光感测,t
4时刻,提供输出控制信号给第2行的感光像素,以控制第2行的感光像素输出感光信号…以此类推,t
2m-1,提供第一扫描驱动信号给第m行的感光像素,以驱动第m行感光像素执行光感测,t
2m时刻,提供输出控制信号给第m行的感光像素,以控制第m行的感光像素输出感光信号。
本实用新型实施方式中的感光装置执行光感测时,在当前行的感光像素执行光感测,且执行光感测时产生的感光信号被读取之后,再进行下一行的感光像素执行光感测,如此使得每一行感光像素的感光信号的读取互不干扰,从而可以获得准确的感光信号。另外,由于感光装置执行一次光感测需要的时间较长,故而可以作为测试模式使用。
进一步地,在某些实施方式中,第一驱动电路241进一步用于:在提供第一扫描驱动信号给当前行的感光像素并达到一预定时间时,提供所述第一扫描驱动信号给下一行的感光像素;所述预定时间为至少一时钟周期。
具体地,由于感光像素22中感光信号通过输出控制信号的控制进行输出,因此不同行的感光像素的光感测时间可以重叠,即当前行的感光像素执行光感测时,可以提供第一扫描驱动信号给下一行的感光像素,以驱动该感光像素执行光感测。需要说明的时, 这里的下一行的感光像素不限于与当前行的感光像素相邻的一行感光像素,也可以指隔行的感光像素。
参照图7,图7示出了图4所示的感光装置执行光感测时的时序,该感光装置采用滚动感光,逐行读出的方式执行光感测。t
11时刻,提供第一扫描驱动信号给第1行的感光像素,以驱动第1行感光像素执行光感测,t
12时刻,提供第一扫描驱动信号给第2行的感光像素,以驱动第2行感光像素执行光感测,t
13时刻,提供第一扫描驱动信号给第3行的感光像素,以驱动第3行感光像素执行光感测,以此类推,t
1m时刻,提供第一扫描驱动信号给第m行的感光像素,以驱动第m行感光像素执行光感测。在每一行的感光像素执行光感测并达到预定时间时,提供输出控制信号给该行的感光像素。如,t
21时刻提供输出控制信号给第1行的感光像素,以控制第1行感光像素的感光信号输出,t
22时刻提供输出控制信号给第2行的感光像素,以控制第2行感光像素的感光信号输出。
由此可知,该感光装置20执行以此光感测的时间较短,而且所有的感光像素等待读取感光信号的时间也一致,即解决了电荷泄漏对感光信号采集造成的影响,从而提高了感测精度。
在某些实施方式中,请继续参照图4,该感光驱动电路进一步包括信号处理单元25,图4所示的感光装置20中的数据线均连接该信号处理单元25,该信号处理单元25可通过硅工艺集成在一颗检测芯片中。当然,该信号处理单元25也可以和感光驱动单元24集成在一颗处理芯片中。具体地,该信号处理单元25用于对所述感光单元222执行光感测时产生的电信号进行读取,并根据读取的电信号获得接触或接近所述感光面板的目标物体的预定生物特征信息。可以理解的是,为了采集到准确有效的电信号,在第二预定时间内,该信号处理单元25可以对感光单元222执行光感测时产生的电信号进行多次读取。
在某些实施方式中,该信号处理单元25包括多个处理通道,可选地,每个处理通道对应连接一条数据线。然,可变更地,也可以每个处理通道对应连接至少两条数据线,通过分时复用的方式,每次选择读取一条数据线上的电信号,然后再选择另一条数据线上的电信号,以此类推,直到所有数据线上的电信号均被读取。如此,可以减少处理通道的个数,从而节省了感光装置20的成本。
请参照图8,图8出了图1中一个感光像素22的另一种电路结构。本实用新型实施方式中的一感光像素22具有第一输入端In1'、第二输入端In2'、第三输入端In3'、第四输入端In4,以及一第一输出端Out1'、第二输出端Out2。光感测控制信号包括第一扫描驱动信号。具体地,该感光像素22包括传感单元和信号输出单元223'。传感单 元具体包括开关单元221'、感光单元222'。其中,开关单元221'通过第三输入端In3'接收一参考信号Vref,另外,开关单元221'还通过第一输入端In1'接收一第一扫描驱动信号,并在接收到第一扫描驱动信号时,将参考信号Vref传输至感光单元222',以驱动感光单元222'执行光感测,信号输出单元223'通过第二输入端In2'接收一输出控制信号,以及通过第四输入端In4接收一恒定电信号Is,以在接收到输出控制信号时,根据感光单元222'执行光感测时产生的电信号将恒定电信号Is转换为二不同的电信号,并从第一输出端Out1'和第二输出端Out2输出。
可选地,上述第一扫描驱动信号和输出控制信号均为一脉冲信号,且第一扫描驱动信号中高电平信号的持续时间为第一预定时间,输出控制信号中高电平的持续时间为第二预定时间。对应地,开关单元221'接收到第一扫描驱动信号时,根据高电平信号闭合,根据低电平信号断开。因此,感光单元222'接收开关单元221'传输过来的参考信号Vref,并在第一预定时间到达时,开始执行光感测。
在某些实施方式中,感光单元222'包括第一分支电路2221和第二分支电路2222。其中,第一分支电路2221用于执行光感测,即接收光信号,并将接收到的光信号转换为相应的电信号;第二分支电路2222用于将第二分支电路2222的第一端的电信号维持在所述参考信号Vref的幅值。具体地,该感光单元222'与图2所示的感光单元222的结构类似,该感光单元222'除了图2所示的感光单元222的结构外,还包括一第二电容c2,且感光器件与第一电容c1为感光单元222'的第一分支电路2221,第二电容c2为感光单元222'的第二分支电路2222。
关于第一分支电路2221,这里定义光电二极管D1的负极与第一电容c1的第一极板为第一分支电路2221的第一端,光电二极管D1的正极与第一电容c1的第二极板为第一分支电路2221的第二端。第一分支电路2221的工作原理请参照前面描述实施。第二分支电路2222中,第二电容c2中第一极板用于接收开关单元221'传输过来的参考信号Vref,第二极板用于接收一固定电信号,例如地信号NGND。参考信号Vref对第二电容c2进行充电,从而使得第二电容c2的第一极板上的电压Vn逐渐上升并在达到参考信号Vref的幅值后保持不变。需要说明的是,这里定义第二电容c2的第一极板为第二分支电路2222的第一端,第二电容c2的第二极板为第二分支电路2222的第二端。
进一步地,在某些实施方式中,开关单元221包括第四晶体管T4和第五晶体管T5。该第四晶体管T4和第五晶体管T5例如但不限于三极管、MOS管、薄膜晶体管中的任意一个或几个。以MOS管为例,该第四晶体管T4包括第四控制电极C4、第七传输电极S7和第八传输电极S8,其中第四控制电极C4为MOS管的栅极,第七传输电极S7 为MOS管的漏极,第八传输电极S8为MOS管的源极。第五晶体管T5包括第五控制电极C5、第九传输电极S9、第十传输电极S10,其中第五控制电极C5为MOS管的栅极,第九传输电极S9为MOS管的漏极,第十传输电极S10为MOS管的源极。
第四控制电极C4和第五控制电极C5均与第一输入端In1'连接,用于接收第一扫描驱动信号;第七传输电极S7和第九传输电极S9均与第三输入端In3'连接,用于接收参考信号Vref;第八传输电极S8与感光单元222'的第一分支电路2221的第一端连接,用于在第四晶体管T4导通时,将参考信号Vref传输至感光单元222'的第一分支电路2221;第十传输电极S10与感光单元222'的第二分支电路2222的第一端连接,用于在第五晶体管T5导通时,将参考信号Vref传输至感光单元222'的第二分支电路2222。
在某些实施方式中,本实施方式中的信号输出单元223'包括第六晶体管T6和转换电路2231。该第六晶体管T6例如但不限于三极管、MOS管、薄膜晶体管中的任意一个或几个。以MOS管为例,第六晶体管T6包括第六控制电极C6、第十一传输电极S11和第十二传输电极S12,其中第六控制电极C6为MOS管的栅极,第十一传输电极S11为MOS管的漏极,第十二传输电极S12为MOS管的源极。第六控制电极C6与第二输入端In2'连接,用于接收输出控制信号;第十一传输电极S11与第四输入端In4连接,用于接收一恒定电流信号Is,第十二传输电极S12与所述转换电路2231连接。所述第六晶体管T6根据输出控制信号导通,以将恒定电流信号Is传输至所述转换电路2231。
进一步地,转换电路2231包括差分对管,该差分对管具有三个输入端和两个输出端,其中一输入端与第六晶体管T6的第十二传输电极S12连接,用于接收第六晶体管T6传输过来的恒定电流信号Is;另外两个输入端对应连接第一分支电路2221的第一端(即光电二极管D1的负极和第一电容c1的第一极板)和第二分支电路2222的第一端(即第二电容c2的第一极板);两个输出端根据第一分支电路2221的第一端的电信号Vp和第二分支电路2222的第一端的电信号Vn,将恒定电流信号Is转换为二不同的电流信号Ip及In,且该二不同的电流信号幅值之和等于恒定电流信号Is的幅值。
具体地,该转换电路2231包括第七晶体管T7和第八晶体管T8。该第七晶体管T7和第八晶体管T8例如但不限于三极管、MOS管中的任意一个或几个。以MOS管为例,该第七晶体管T7包括第七控制电极C7、第十三传输电极S13和第十四传输电极S14,其中第七控制电极C7为MOS管的栅极,第十三传输电极S13为MOS管的漏极,第十四传输电极S14为MOS管的源极。第八晶体管T8包括第八控制电极C8、第十五传输电极S15、第十六传输电极S16,其中第八控制电极C8为MOS管的栅极,第十五传输 电极S15为MOS管的漏极,第十六传输电极S16为MOS管的源极。
第七晶体管T7的第七控制电极C7与第一分支电路2221的第一端(如第一电容c1的第一极板)连接;第十三传输电极S13与第六晶体管T6的第十二传输电极S12连接,用于接收第六晶体管T6传输过来的恒定电流信号Is;第十四传输电极S14与第一输出端Out1'连接,用于输出一电流信号Ip。第八晶体管T8的第八控制电极C8与第二分支电路2222的第一端(如第二电容c2的第一极板)连接;第十五传输电极S15与第六晶体管T6的第十二传输电极S12连接,用于接收第六晶体管T6传输过来的恒定电流信号Is;第十六传输电极S16与第二输出端Out2连接,用于输出另一电流信号In。
进一步地,第七晶体管T7和第八晶体管T8组成一差分对管,当第七晶体管T7的第七控制电极C7上的电压Vp和第八晶体管T8的第八控制电极C8上的电压Vn相等时,该差分对管处于平衡状态,第七晶体管T7的第十四传输电极S14和第八晶体管T8的第十六传输电极S16输出幅值相等的电流信号。当第七晶体管T7的第七控制电极C7上的电压Vp和第八晶体管T8的第八控制电极C8上的电压Vn存在压差时,该差分对管输出二幅值不同的差分电信号。通过将该二幅值不同的差分电信号输入至差分放大器的两输入端,从而可以获得相应的放大电信号。
请参照图9,图9示出了图8的感光像素22执行光感测时各节点处的信号时序,其中Vp为光电二极管D1负极以及第一电容c1第一极板上的电压信号;Vn为第二电容c2第一极板上的电压信号;Ip为第七晶体管T7的第十四传输电极S14输出的电流信号,In为第八晶体管T8的第十六传输电极S16输出的电流信号。
t1时刻,通过第一输入端In1'输入第一扫描驱动信号,第四晶体管T4和第五晶体管T5根据高电平信号导通。
当第四晶体管T4导通时,参考信号Vref经第七传输电极S7和第八传输电极S8传输至光电二极管D1的负极和第一电容c1的第一极板上。由于光电二极管D1内部具有一等效电容,因此参考信号Verf对光电二极管D1内部的等效电容进行充电,从而使得光电二极管D1的负极上的电压Vp逐渐上升并在达到参考信号Vref的电压值后保持不变。另外,参考信号Vref还对第一电容c1进行充电,从而使得第一电容c1的第一极板上的电压逐渐上升并在达到参考信号Vref的电压值后保持不变。
当第五晶体管T5导通时,参考信号Vref经第九传输电极S9和第十传输电极S10传输至第二电容c2的第一极板上,从而对第二电容c2进行充电,第二电容c2的第二极板上的电压Vn逐渐上升并在达到参考信号Vref的电压值后保持不变。
t2时刻,第一扫描驱动信号由高电平信号转为低电平信号,因此第一输入端In1变 为低电平信号,第四晶体管T4和第五晶体管T5均截止。当第四晶体管T4截止时,等效电容和第一电容c1与光电二极管D1之间形成放电回路。感光单元222'开始执行光感测。此时,若光电二极管D1上有光信号照射,则光电二极管D1内部产生与光信号成正比的电流信号,因此光电二极管D1负极上的电压Vp逐渐降低。而且,光信号越强,电压Vp降低的速度越快。当第五晶体管T5截止时,由于第二电容c2无法形成放电回路,因此第二电容c2的第一极板上的电压Vn保持不变。
t3时刻,通过第二输入端In2'输入输出控制信号,第六晶体管T6根据高电平信号导通,恒定电流信号Is传输至转换电路2231。转换电路2231根据电压Vp和电压Vn的压差输出两个幅值不同的电流信号。随着电压Vp的下降,电压Vn与电压Vp之间的压差越来越大,从而差分对管输出两个幅值不同的电流信号。如图9所示,第一输出端Out1'输出的电流信号Ip的幅值随电压Vp的下降而下降,由于差分对管的特性,第二输出端Out2输出的电流信号In的幅值由低电平逐渐上升至电压Vn对应的电流值后随电流信号Ip的下降而上升。而且,若该两路差分信号输入至差分放大器中后输出的电信号则相比一路电信号放大了一倍,从而达到了信号放大的作用。
t4时刻,输出控制信号由高电平信号转为低电平信号,因此第二输入端In2'变为低电平信号,则第六晶体管T6截止,第一输出端Out1'和第二输出端Out2停止输出电信号,变为低电平信号。上述t4时刻和t3时刻之间定义为第二预定时间Δt1,在这段时间内,通过从第一输出端Out1'和第二输出端Out2处获取相应的电流信号,并根据该两路电流信号,即可获得感光单元222'执行光感测而产生的感光信号的大小,进而生成目标物体的生物特征信息。
进一步地,上述第二预定时间Δt1可以为固定值,也可以为变化值。由于光电二极管D1接收到的光信号越大,电压Vp的降低速度越快,因此,为实现感光信号的准确有效地获取,根据接收到的光信号的强度调整Δt1的大小。具体地,光信号的强度越大,则Δt1越短;光信号的强度越小,则Δt1越长。
进一步地,上述t3时刻与t2时刻之间的间隔不能过长,也不能过短,以保证感光信号及时有效地输出。因为t2时刻时,感光单元222'开始执行光感测,即将产生相应的电信号,间隔时间过长可能感光信号的及时输出,间隔时间过短可能感光单元222'未来得及产生有效的感光信号,能控制感光单元222'产生的电信号及时有效地输出。
本实用新型实施方式的感光像素22通过感光信号的输出控制,能保证感光信号及时有效的输出,而且通过转换电路2231,使得感光单元222执行光感测而产生的电流信号以两路差分信号的方式输出,从而实现了电信号的放大,提高了感光装置20的感测 精度。另外,由于该两路差分信号均为电流信号,相对电压信号的输出,提高了信号的抗干扰能力,进一步提高了感光装置20的感测精度。
进一步地,参照图10,图10示出了本实用新型另一实施方式的感光装置中,感光像素与扫描线、数据线和信号参考线之间的连接结构,而且该感光像素为图8示出的电路结构。感光装置20进一步包括与多个感光像素22电性连接的扫描线组、数据线组、信号参考线组。其中,扫描线组包括由多条第一扫描线组成的第一扫描线组和由多条第二扫描线组成的第二扫描线组,数据线组包括多条第一数据线、多条第二数据线、多条第三数据线,信号参考线组包括多条信号参考线。以图1中的感光阵列201为例,该感光阵列201中,X方向上的一行感光像素包括间隔排列的n个感光像素22,Y方向上的一列感光像素包括间隔排列的m个感光像素22,因此该感光阵列201一共包括m*n个感光像素。与感光像素22连接的扫描线组、数据线组、信号参考线组的数量对应设置。具体地,第一扫描线组包括m条第一扫描线、m条第二扫描线,且该m条第一扫描线沿Y方向间隔排列,例如G11、G12、…G1m,该m条第二扫描线也沿Y方向间隔排列,例如G21、G22、…G2m。信号参考线组包括m条信号参考线,且该m条信号参考线沿Y方向间隔排列,例如L1、L2、…Lm。数据线组包括n条第一数据线、n条第二数据线、n条第三数据线,且该n条第一数据线沿X方向间隔排列,例如S11、S12、…S1n;该n条第二数据线也沿X方向间隔排列,例如S21、S22、…S2n;该n条第三数据线也沿X方向间隔排列,例如S31、S32、…S3n。当然,感光装置20的扫描线组、数据线组和信号参考线组也可以为其他规则方式分布或非规则方式分布。另外,由于第一扫描线、第二扫描线、信号参考线和第一数据线、第二数据线、第三数据线均具有导电性,因此处于交叉位置的各线路之间通过绝缘材料进行隔离。
具体地,m条第一扫描线对应与多个感光像素22的第一输入端In1'连接,m条第二扫描线对应与多个感光像素22的第二输入端In2'连接,m条信号参考线对应与多个感光像素22的第三输入端In3'连接,n条第一数据线对应与多个感光像素22的第一输出端Out1'连接,n条第二数据线对应与多个感光像素22的第二输出端Out2连接、第三数据线与感光像素22的第四输入端In4连接。其中,第一扫描线、第二扫描线、信号参考线均从X方向上引出,第一数据线和第二数据线则从Y方向上引出。
在某些实施方式中,感光装置20进一步包括感光驱动电路,该感光驱动电路用于依次驱动所述多个感光像素执行光感测;在所述感光像素开始执行光感测后,控制该感光像素执行光感测时产生的电信号输出。
在某些实施方式中,请继续参照图10,该感光驱动电路包括一感光驱动单元24, 感光装置20中的第一扫描线、第二扫描线、信号参考线均连接至该感光驱动单元24。请参照图11,图11示出了本实用新型一实施方式的感光驱动单元的功能模块。该感光驱动单元24包括提供第一扫描驱动信号的第一驱动电路241'、提供输出控制信号的第二驱动电路242'和提供参考信号Vref的参考电路243'。该感光驱动单元24的各电路可通过硅工艺集成在一颗控制芯片中,当然该感光驱动单元24的各电路也可以分开形成在不同的控制芯片中。例如,第一驱动电路241'和第二驱动电路242'与感光像素22一起形成在同一基板上,参考电路243'则通过一连接件(例如,柔性电路板)与感光装置20的多条信号参考线连接。
在某些实施方式中,参考电路243'用于提供参考信号Vref,该参考电路243'通过感光像素22的第三开关(例如,图8所示的开关单元221'中的第四晶体管T4)可选择性地与所述感光单元222'的第一分支电路2221电性连接。在第三开关闭合时,该参考信号Vref通过闭合的第三开关传输至相应的感光单元222'的第一分支电路2221。同时,该参考电路243'还通过感光像素22的第四开关(例如,图8所示的开关单元221'中的第五晶体管T5)可选择性地与所述感光单元222'的第二分支电路2222电性连接。在第四开关闭合时,该参考信号Vref通过闭合的第四开关传输至相应的感光单元222'的第二分支电路2222。
第一驱动电路241'与感光装置20的第一扫描线电性连接,用于逐行或隔行提供第一扫描驱动信号给所述多个感光像素22中的第三开关和第四开关,以控制第三开关和第四开关闭合,并在第一预定时间到达时,控制第三开关和第四开关断开,从而驱动感光单元222'开始执行光感测。
第二驱动电路242'与感光装置20的第二扫描线电性连接,用于在驱动感光单元222'开始执行光感测后,例如第三开关和第四开关断开并达到第四预定时间(图9所示的t3-t2)时,提供输出控制信号给第五开关(例如图8所示的信号输出单元223'中的第六晶体管T6),以控制第五开关闭合,并在第二预定时间到达时,控制第五开关断开,从而转换电路2231根据感光单元222'执行光感测时产生的电信号,将恒定电流信号转换为二不同的电流信号,并输出。
进一步地,第一驱动电路241'对多个感光像素22的控制方式与上述第一驱动电路241对多个感光像素22的控制方式一致。即,在提供所述第一扫描驱动信号给当前行的感光像素,且提供所述输出控制信号给该当前行的感光像素,以控制该当前行的感光像素执行光感测时产生的电信号输出后,再提供所述第一扫描驱动信号给下一行的感光像素,从而实现感光像素22的逐行感光,逐行读出;或者,在提供第一扫描驱动信号给当前行的感光像 素并达到一预定时间时,提供所述第一扫描驱动信号给下一行的感光像素;所述预定时间为至少一时钟周期,从而实现感光像素22的滚动感光,逐行读出。
在某些实施方式中,请继续参照图10,该感光驱动电路进一步包括信号处理单元25,图10所示的感光装置20中的数据线组均连接该信号处理单元25。具体地,第三数据线例如连接一恒流源(图中未示出),该恒流源用于提供一恒定电流信号;第一数据线和第二数据线例如连接一信号处理电路(图中未示出)。当然,该信号处理单元25也可以和感光驱动单元24集成在一颗处理芯片中。该信号处理单元25用于对所述感光单元222'执行光感测时产生的电信号进行读取,并根据读取的电信号获得接触或接近所述感光装置的目标物体的预定生物特征信息。该信号处理单元25可通过硅工艺集成在一颗检测芯片中。可以理解的是,为了采集到准确有效的电信号,在第二预定时间内,该信号处理单元25可以对感光单元222'执行光感测时产生的电信号进行多次读取。
在某些实施方式中,该信号处理单元25包括多个处理通道,可选地,每个处理通道对应连接一条第一数据线、第二数据线。然,可变更地,也可以每个处理通道对应连接至少两条第一数据线、至少两条第二数据线,通过分时复用的方式,每次选择读取一条第一数据线和一条第二数据线上的电信号,然后再选择另一条第一数据线和第二数据线上的电信号,以此类推,直到所有第一数据线和第二数据线上的电信号均被读取。如此,可以减少处理通道的个数,从而节省了感光装置20的成本。
在某些实施方式中,请参照图12,图12示出了本实用新型另一实施方式的感光装置的结构。该感光装置20进一步包括一感光面板200,该感光面板200又包括一基底26,多个感光像素22设置于该基底26上。可选地,该感光像素22呈阵列分布。上述感光驱动电路用于驱动该多个感光像素执行光感测,并控制感光像素执行光感测时产生的电信号输出。该感光像素22执行光感测时,用于接收上方来的光信号,并将接收到的光信号转换为相应的电信号,因此多个感光像素22的感光区域界定形成感测区域203,感测区域203以外的区域则为非感测区域202。为了方便线路布设,该非感测区域202用于设置感光像素22执行光感测所需的驱动电路,例如上述感光驱动电路。或者,该非感测区域202用于设置供电性连接件连接的线路绑定区。例如,以图11所示的感光驱动电路为例,第一驱动电路241'和第二驱动电路242'、参考电路243'均形成在基底26上。或者,第一驱动电路241'、第二驱动电路242'、参考电路243'通过电性连接件(例如,柔性电路板)与感光像素22电性连接。
在某些实施方式中,上述信号处理单元25可根据基底26的类型是选择形成在基底26上,还是选择例如通过电性连接件(例如,柔性电路板)与感光像素22电性连接。 例如,当所述基底26为硅基底时,所述信号处理单元25可选择形成在基底26上,也可选择例如通过柔性电路板与感光像素22电性连接;当所述基底26为绝缘基底时,所述信号处理单元25则需要例如通过柔性电路板与感光像素22电性连接。
在某些实施方式中,该感光装置20为一感光芯片,用于感测接触或接近感光装置20的目标物体的生物特征信息。可选地,该感光装置20为一指纹感测芯片,用于感测用户手指的指纹图像。
进一步地,基于上述感光装置,本实用新型实施方式还提供一种感光装置的光感测方法。参照图13,图13示出了本实用新型一实施方式的感光装置的光感测方法的具体步骤,该感光装置的光感测方法包括以下步骤:
步骤S21,依次提供第一扫描驱动信号给所述多个感光像素,以使所述感光像素在第一预定时间到达时,开始执行光感测;
步骤S22,在所述感光像素开始执行光感测后,提供输出控制信号给所述多个感光像素,控制所述感光像素执行光感测时产生的电信号输出。
进一步地,上述步骤S21具体可包括:逐行或隔行驱动提供所述第一扫描驱动信号给所述多个感光像素,以驱动所述感光像素执行光感测。如此可以实现一次驱动一行感光像素执行光感测,从而加快感测速度。
具体地,基于图4所示的感光装置20以及图2所示的感光像素结构,步骤S21具体为:依次提供第一扫描驱动信号给多个感光像素22中的第一开关(例如,图2所示的开关单元221中的第一晶体管T1),以控制第一开关闭合,并在第一预定时间到达时,控制第一开关断开,从而驱动感光单元222开始执行光感测。
步骤S22具体为:在开关单元221的第一开关断开后,提供输出控制信号给多个感光像素22的第二开关(例如,图2所示的信号输出单元223中的第二晶体管T2),控制第二开关闭合,以使感光单元222执行光感测时产生的电信号输出。
基于图10所示的感光装置以及图8所示的感光像素结构,步骤S11具体为:依次提供第一扫描驱动信号给所述多个感光像素22中的第三开关(例如,图8所示的开关单元221'中的第四晶体管T4)和第四开关(例如,图8所示的开关单元221'中的第五晶体管T5),以控制第三开关和第四开关闭合,并在第一预定时间到达时,控制第三开关和第四开关断开,从而驱动感光单元222'开始执行光感测。
步骤S22具体为:第三开关和第四开关断开并达到第四预定时间(图9所示的t3-t2)时,提供输出控制信号给第五开关(例如图8所示的信号输出单元223'中的第六晶体管T6),以控制第五开关闭合,并在第二预定时间到达时,控制第五开关断开,从 而转换电路2231根据感光单元222'执行光感测时产生的电信号,将恒定电流信号转换为二不同的电流信号,并输出。
进一步地,在某些实施方式中,上述步骤S21进一步包括:在提供所述第一扫描驱动信号给当前行的感光像素,且提供所述输出控制信号给该当前行的感光像素,以控制该当前行的感光像素执行光感测时产生的电信号输出后,再提供所述第一扫描驱动信号给下一行的感光像素。需要说明的时,这里的下一行的感光像素不限于与当前行的感光像素相邻的一行感光像素,也可以指隔行的感光像素。
具体地,继续参照图6,该感光装置采用逐行感光,逐行读出的方式执行光感测。t
1时刻,提供第一扫描驱动信号给第1行的感光像素,以驱动第1行感光像素执行光感测,t
2时刻,提供输出控制信号给第1行的感光像素,以控制第1行的感光像素输出感光信号;t
3时刻,提供第一扫描驱动信号给第2行的感光像素,以驱动第2行感光像素执行光感测,t
4时刻,提供输出控制信号给第2行的感光像素,以控制第2行的感光像素输出感光信号…以此类推,t
2m-1,提供第一扫描驱动信号给第m行的感光像素,以驱动第m行感光像素执行光感测,t
2m时刻,提供输出控制信号给第m行的感光像素,以控制第m行的感光像素输出感光信号。
本实用新型实施方式中的感光装置执行光感测时,在当前行的感光像素执行光感测,且执行光感测时产生的感光信号被读取之后,再进行下一行的感光像素执行光感测,如此使得每一行感光像素的感光信号的读取互不干扰,从而可以获得准确的感光信号。另外,由于感光装置执行一次光感测需要的时间较长,故而可以作为测试模式使用。
进一步地,在某些实施方式中,上述步骤S21进一步包括:在提供第一扫描驱动信号给当前行的感光像素并达到一预定时间时,提供所述第一扫描驱动信号给下一行的感光像素;所述预定时间为至少一时钟周期。
具体地,由于感光像素22中感光信号通过输出控制信号的控制进行输出,因此不同行的感光像素的光感测时间可以重叠,即当前行的感光像素执行光感测时,可以提供第一扫描驱动信号给下一行的感光像素,以驱动该感光像素执行光感测。需要说明的时,这里的下一行的感光像素不限于与当前行的感光像素相邻的一行感光像素,也可以指隔行的感光像素。
继续参照图7,该感光装置采用滚动感光,逐行读出的方式执行光感测。t
11时刻,提供第一扫描驱动信号给第1行的感光像素,以驱动第1行感光像素执行光感测,t
12时刻,提供第一扫描驱动信号给第2行的感光像素,以驱动第2行感光像素执行光感测,t
13时刻,提供第一扫描驱动信号给第3行的感光像素,以驱动第3行感光像素执行光感 测,以此类推,t
1m时刻,提供第一扫描驱动信号给第m行的感光像素,以驱动第m行感光像素执行光感测。在每一行的感光像素执行光感测并达到预定时间时,提供输出控制信号给该行的感光像素。例如,t
21时刻提供输出控制信号给第1行的感光像素,以控制第1行感光像素的感光信号输出,t
22时刻提供输出控制信号给第2行的感光像素,以控制第2行感光像素的感光信号输出。
由此可知,该感光装置20执行以此光感测的时间较短,而且所有的感光像素等待读取感光信号的时间也一致,即解决了电荷泄漏对感光信号采集造成的影响,从而提高了感测精度。
进一步地,参照图14和图15,图14示出了本实用新型一实施方式的电子设备的结构,图15示出了图14所示的电子设备沿I-I线的剖面结构,而且图15仅示出了电子设备的部分结构。该电子设备包括上述任意一实施结构的感光装置,既用于电子设备的图像显示,又用于对接触或接近电子设备的目标物体的生物特征信息进行感测。
电子设备例如但不局限为消费性电子产品、家居式电子产品、车载式电子产品、金融终端产品等合适类型的电子产品。其中,消费性电子产品如为手机、平板电脑、笔记本电脑、桌面显示器、电脑一体机等。家居式电子产品如为智能门锁、电视、冰箱、穿戴式设备等。车载式电子产品如为车载导航仪、车载DVD等。金融终端产品如为ATM机、自助办理业务的终端等。图14示出的电子设备以手机类的移动终端为例,然上述生物感测模组也可适用于其它合适的电子产品,并不局限于手机类的移动终端。
具体地,该移动终端3的正面设有一显示装置(未示出),该显示装置包括一显示面板300,该显示面板300上方设有保护盖板400。可选地,该显示面板300的屏占比较高,例如80%以上。屏占比是指显示面板300的显示区域305占移动终端3的正面区域的比例。该感光装置20(参见图4及图10)中感光面板200为一与显示面板300适配的面板结构,且对应设置在该显示面板300的下方。若该显示面板300为柔性曲面状,则该感光面板200也为柔性曲面状。因此,该感光面板200并不仅表示平面结构,也可以为曲面结构。如此,便于感光面板200与显示面板300的层叠组装。
由于感光面板200位于显示面板300下方,因此显示面板300具有供目标物体反射回来的光信号穿过的透光区域,从而使得感光面板200能接收到穿过显示面板300的光信号,并将接收到的光信号转换为电信号,根据转换后的电信号获取接触或接近电子设备的目标物体的预定生物特征信息。
本实用新型实施方式中,该电子设备除了具有上述实施方式中描述的感光装置20的效果外,还利用显示面板300发出的光信号实现目标物体的生物特征信息感测,不需 要额外设置光源,从而不但节省了电子设备的成本,而且还实现了对接触或触摸显示面板300的显示区域305内目标物体进行生物特征信息感测。另外,该感光装置20可以独立制成后,再进行电子设备的组装,从而加快了电子设备的制备。
当移动终端3处于亮屏状态、且处于生物特征信息感测模式时,该显示面板300发出光信号。当一物体接触或接近该显示区时,该感光装置20接收由该物体反射回来的光信号,转换接收到的光信号为相应的电信号,并根据该电信号获取该物体的预定生物特征信息,例如,指纹图像信息。从而,该感光装置20可实现对接触或接近显示区域任意位置的目标物体进行感测。
在某些实施方式中,显示面板300例如但不限于OLED显示器件,只要能实现显示效果且具有供光信号穿过的透光区域的显示器件均在本实用新型的保护范围。另外,显示面板300可以为底发射结构、顶发射结构、双面透光结构,而且,该显示屏可以为刚性材质的硬屏,也可以为柔性材质的柔性屏。
在某些实施方式中,感光面板200用于执行对显示面板300的显示区域内任意位置的目标物体的生物特征信息感测。例如,具体地,例如请结合参照图14、图15和图16,显示面板300具有一显示区域305和非显示区域306,该显示区域305由显示面板300的所有显示像素32的发光区域界定,显示区域305以外的区域为非显示区域306,非显示区域306用于设置驱动显示像素32的显示驱动电路等电路或者设置供柔性电路板连接的线路绑定区。感光面板200具有一感测区域203和非感测区域204,该感测区域203由感光面板200的所有感光像素22的感测区域界定,感测区域203以外的区域为非感测区域204,非感测区域204用于设置驱动感光像素22执行光感测的感光驱动单元24等电路或者供柔性电路板连接的线路绑定区。感测区域203的形状与显示区域305的形状一致,且感测区域203的大小大于或等于显示区域305的大小,如此使得感光面板200能对接触或接近显示面板300的显示区域305任意位置的目标物体的预定生物特征信息的感测。进一步地,感光面板200的面积小于或等于显示面板300的面积,且感光面板200的形状与显示面板300的形状一致,如此便于感光面板200与显示面板300的组装。然,可变更地,在某些实施方式中,感光面板200的面积也可以大于显示面板300的面积。
在某些实施方式中,所述感光面板200的感测区域203也可为小于显示面板300的显示区域305,以实现显示面板300显示区域305的局部区域的目标物体的预定生物特征信息的感测。
进一步地,显示装置进一步用于执行触摸感测,当所述显示装置检测到目标物体的 触摸或接近之后,所述控制显示面板对应触摸区域的位置发光。
然,可变更地,在某些实施方式中,请参照图17以及图18,图17示出了本实用新型一实施方式的电子设备的结构,图18示出了图17所示的电子设备沿II-II线的剖面结构,而且图18仅示出了电子设备的部分结构。本实用新型实施方式的感光模组应用于一移动终端3,该移动终端的正面设有一显示面板300,该显示面板300上方设有保护盖板400。该显示面板300的屏占比较高,例如80%以上。屏占比是指显示面板300的实际显示区域305占移动终端的正面区域的比例。该显示面板300的实际显示区域305的中下位置处设有一供目标物体触摸的生物感测区域S,以进行目标物体的生物特征信息感测,例如目标物体为手指,则该生物感测区域S为指纹识别区域,以进行指纹识别。对应地,显示面板300下方对应该指纹识别区域S的位置设有一感光装置20,该感光装置20用于在手指放置于指纹识别区域S时,获取该手指的指纹图像。可以理解的是,设置于显示面板300的中下位置是为了用户手持移动终端时,方便手指触摸显示面板300的位置。当然,也可以设置于方便手指触摸的其他位置。
在某些实施方式中,电子设备进一步包括一触摸传感器(图中未示出),通过该触摸传感器可以确定目标物体在保护盖板400上的触摸区域。该触摸传感器采用电容触摸感测技术,当然也可以通过其他方式,例如电阻式触摸感测、压感式触摸感测等等。所述触摸传感器用于在一目标物体接触所述保护盖板400时,确定所述目标物体的触摸区域,以驱动对应触摸区域的显示像素点亮以及感光像素执行光感测。
在某些实施方式中,所述触摸传感器或者与所述保护盖板400集成,或者与感光面板200集成,或者与显示面板300集成。通过集成的触摸传感器,不但实现了对目标物体的触摸检测,而且也减小了电子设备的厚度,有利于电子设备朝轻薄化方向发展。
在本说明书的描述中,参考术语“一个实施方式”、“某些实施方式”、“示意性实施方式”、“示例”、“具体示例”、或“一些示例”等的描述意指结合所述实施方式或示例描述的具体特征、结构、材料或者特点包含于本实用新型的至少一个实施方式或示例中。在本说明书中,对上述术语的示意性表述不一定指的是相同的实施方式或示例。而且,描述的具体特征、结构、材料或者特点可以在任何的一个或多个实施方式或示例中以合适的方式结合。
尽管上面已经示出和描述了本实用新型的实施方式,可以理解的是,上述实施方式是示例性的,不能理解为对本实用新型的限制,本领域的普通技术人员在本实用新型的范围内可以对上述实施方式进行变化、修改、替换和变型。
Claims (14)
- 一种感光驱动电路,其特征在于:所述感光驱动电路用于依次驱动所述多个感光像素执行光感测;在所述感光像素开始执行光感测后,控制该感光像素执行光感测时产生的电信号输出。
- 如权利要求1所述的感光驱动电路,其特征在于:所述多个感光像素呈阵列分布于一基底上,且所述基底上还设有多条分别与所述多个感光像素电性连接的第一扫描线;所述感光驱动电路包括:第一驱动电路,对应与所述第一扫描线电性连接,用于逐行或隔行提供一第一扫描驱动信号给所述多个感光像素,以驱动所述多个感光像素逐行或隔行执行光感测。
- 如权利要求2所述的感光驱动电路,其特征在于:所述第一驱动电路进一步用于:在提供所述第一扫描驱动信号给当前行的感光像素,以及提供所述输出控制信号给该当前行的感光像素,以驱动该当前行的感光像素执行光感测,且控制执行光感测时产生的电信号输出后,再提供所述第一扫描驱动信号给下一行的感光像素。
- 如权利要求2所述的感光驱动电路,其特征在于:所述第一驱动电路进一步用于:在提供所述第一扫描驱动信号给当前行的感光像素并达到一预定时间时,提供所述第一扫描驱动信号给下一行的感光像素;所述预定时间为至少一时钟周期。
- 如权利要求2所述的感光驱动电路,其特征在于:所述基底上还设有多条与所述多个感光像素电性连接的第二扫描线;所述感光驱动电路进一步包括:第二驱动电路,该第二驱动电路对应与所述第二扫描线电性连接,用于在每个感光像素开始执行光感测并达到第四预定时间时,提供所述输出控制信号给该感光像素,以控制该感光像素执行光感测时产生的电信号输出。
- 如权利要求5所述的感光驱动电路,其特征在于:所述第二驱动电路进一步用于:控制所述感光像素执行光感测时产生的电信号输出并持续第二预定时间。
- 如权利要求6所述的感光驱动电路,其特征在于:所述第二预定时间根据接收到的光信号的强度进行动态调整。
- 如权利要求7所述的感光驱动电路,其特征在于:所述接收到的光信号的强度越大,第二预定时间越短;所述接收到的光信号的强度越小,第二预定时间越长。
- 如权利要求2所述的感光驱动电路,其特征在于:所述基底上还设有与所述多个感光像素电性连接的数据线;所述感光驱动电路进一步包括信号处理单元,所述信号处理单元与所述多条数据线电性连接,用于对所述感光像素输出的电信号进行读取,并根据读取的电信号获得接触或接近所述感光像素的目标物体的预定生物特征信息。
- 如权利要求9所述的感光驱动电路,其特征在于:所述感光驱动电路形成在所述基底上或者通过一电性连接件与所述多个感光像素电性连接;或者,所述感光驱动电路的一部分电路形成在所述基底上,另一部分电路通过一连接件与所述多个感光像素电性连接。
- 一种感光装置,其特征在于:包括多个感光像素及如权利要求1-10中任意一项所述的感光驱动电路,所述感光驱动电路用于驱动所述多个感光像素执行光感测,并在所述感光像素开始执行光感测后,控制该感光像素执行光感测时产生的电信号输出。
- 如权利要求11所述的感光装置,其特征在于:所述感光装置为指纹感测装置,用于采集手指的指纹信息。
- 如权利要求11所述的感光装置,其特征在于:所述感光装置为一生物感测芯片,用于获取接近或接触所述感光装置的目标物体的预定生物特征信息。
- 一种电子设备,其特征在于:包括如权利要求11-13中任意一项所述的感光装置。
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