WO2020238664A1 - 显示设备 - Google Patents

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Publication number
WO2020238664A1
WO2020238664A1 PCT/CN2020/090758 CN2020090758W WO2020238664A1 WO 2020238664 A1 WO2020238664 A1 WO 2020238664A1 CN 2020090758 W CN2020090758 W CN 2020090758W WO 2020238664 A1 WO2020238664 A1 WO 2020238664A1
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WO
WIPO (PCT)
Prior art keywords
bit
light source
bit plane
sequence
time
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Application number
PCT/CN2020/090758
Other languages
English (en)
French (fr)
Inventor
陈晨
胡飞
余新
郭祖强
李屹
Original Assignee
深圳光峰科技股份有限公司
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Application filed by 深圳光峰科技股份有限公司 filed Critical 深圳光峰科技股份有限公司
Priority to US17/601,388 priority Critical patent/US11600238B2/en
Publication of WO2020238664A1 publication Critical patent/WO2020238664A1/zh

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3141—Constructional details thereof
    • H04N9/315—Modulator illumination systems
    • H04N9/3155—Modulator illumination systems for controlling the light source
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/3433—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using light modulating elements actuated by an electric field and being other than liquid crystal devices and electrochromic devices
    • G09G3/346—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using light modulating elements actuated by an electric field and being other than liquid crystal devices and electrochromic devices based on modulation of the reflection angle, e.g. micromirrors
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/2007—Display of intermediate tones
    • G09G3/2018—Display of intermediate tones by time modulation using two or more time intervals
    • G09G3/2022—Display of intermediate tones by time modulation using two or more time intervals using sub-frames
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/2007—Display of intermediate tones
    • G09G3/2077—Display of intermediate tones by a combination of two or more gradation control methods
    • G09G3/2081—Display of intermediate tones by a combination of two or more gradation control methods with combination of amplitude modulation and time modulation
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G5/00—Control arrangements or circuits for visual indicators common to cathode-ray tube indicators and other visual indicators
    • G09G5/10—Intensity circuits
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/0233—Improving the luminance or brightness uniformity across the screen
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/04—Maintaining the quality of display appearance
    • G09G2320/043—Preventing or counteracting the effects of ageing
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/06—Adjustment of display parameters
    • G09G2320/0626—Adjustment of display parameters for control of overall brightness
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/06—Adjustment of display parameters
    • G09G2320/0626—Adjustment of display parameters for control of overall brightness
    • G09G2320/0633—Adjustment of display parameters for control of overall brightness by amplitude modulation of the brightness of the illumination source
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection

Definitions

  • the present invention relates to the field of display technology, and in particular to a display device.
  • the display bit depth of the image is related to the crossover time and the switching time of the DMD.
  • the turning time is generally 1 to 3 microseconds, which is the time required for the micro-mirror to turn from one state to another state.
  • the switching time generally more than 10 microseconds, is the time required for a single micro-mirror to change from one state to another continuous change.
  • the switching time is longer than the flipping time for the stable shaking time of the micro-mirror. In theory, the switching time determines the number of flips of a single micro-mirror in a frame of image, and therefore also determines the display bit depth of the image.
  • Commonly used methods in the prior art to achieve high bit depth mainly include DMD clear operation, DMD dithering, and light intensity control of the light source.
  • the reset operation can make all the micro-mirrors return to the "off" state without waiting for the stable shaking time. Therefore, the reset operation can shorten the switching time to the flip time to increase the display bit depth of the image .
  • the maximum average brightness of the image display will be reduced, and the more the bit depth is increased, the more the average brightness of the image display will decrease.
  • the jitter of DMD can be divided into space jitter and time jitter. For example, if only half of the pixels that are spatially adjacent are bright in one display period, as shown in Figure 1, among the four adjacent pixels numbered 1, 2, 3, and 4, the pixels 1 and pixel 4 are bright, or pixel 2 and pixel 3 are bright, when the pixels are small enough or the human eye is far enough from the screen, the average brightness of the four pixels seen by the human eye is half of the minimum brightness that a single pixel can display .
  • time jitter can also be used to make the pixels adjacent to the DMD display in turn. For example, the above four pixels can be displayed in turn within four image frame times, which can achieve a smaller brightness unit while avoiding the display screen. Repeating pattern.
  • the dithering of the DMD increases the bit depth by reducing the minimum brightness unit of the image display, while also sacrificing the maximum average brightness of the image display.
  • the principle of the light intensity control of the light source is to reduce the light intensity of the light source within the time corresponding to the Least Significant Bit (LSB) to achieve a lower gray scale display. For example, in the time corresponding to LSB, if the luminous intensity of the light source is adjusted to the original Then the brightness corresponding to LSB becomes the original At this time, the bit display depth of the image has increased by 4 bits.
  • the light intensity control of the light source also sacrifices the maximum average brightness of the image display to increase the image display bit depth.
  • the prior art achieves high bit depth by reducing the minimum brightness, so that the details of the dark part of the image to be displayed can be reflected, but the above methods all lead to a reduction in the maximum average brightness of the image display, and the ambient light brightness in the projection system is higher. At this time, the increased gray-scale details in the low-brightness range will be masked by the ambient light.
  • the present invention provides a display device, which can solve the problem that the display bit depth of the existing display device is limited and the maximum average display brightness is reduced within one frame.
  • the present invention adopts a technical solution: a light source; a light modulator, including a digital micro-mirror array containing a plurality of micro-mirrors, arranged on the light path of the light source from the light source, and used to control the light source according to the target image and the brightness of the light source
  • the emitted light is modulated to obtain a grayscale image; and a control device for controlling the driving current of the light source, so that the luminous brightness of the light source is adjusted in a period of time within a frame of image time, and the driving current of the light source is overshooted in at least part of the period,
  • the display bit depth of the grayscale image is increased from n to n+i (i ⁇ 1 and i is an integer), and each period corresponds to the bit plane of the grayscale image one to one.
  • modulating the emitted light of the light source according to the target image and the luminous brightness of the light source includes: the grayscale image includes n+i bit planes, and when any one of the n+i bit planes is displayed, The modulation duration of the light modulator corresponds to the number of least significant bits contained in the bit plane.
  • adjusting the light-emitting brightness of the light source in a period of time within a frame of image, and overshooting the driving current of the light source during at least part of the period includes the following steps: the gray-scale image includes n+i bit planes, When there are i bit planes, each bit plane contains only one least significant bit.
  • k 2 j L,0 ⁇ j ⁇ i-1,j
  • L is the preset brightness parameter
  • the driving current of the light source to make the light-emitting brightness of the light source 2 i L.
  • the display bit depth of the display device can be increased; it is beneficial to shorten the single frame display time and achieve a high frame rate; in addition, it is beneficial to increase the maximum average image display that can be achieved within one frame Display brightness.
  • adjusting the light-emitting brightness of the light source in a period of time within a frame of image, and overshooting the driving current of the light source during at least part of the period includes the following steps: the gray-scale image includes n+i bit planes, When there are i bit planes, the number of least significant bits contained in each bit plane corresponds to the i values of x in the set ⁇ x
  • x 2 j ,0 ⁇ j ⁇ i-1,j ⁇ Z ⁇ , Adjust the driving current of the light source so that the light-emitting brightness of the light source is L, where L is the preset brightness parameter; and when displaying the remaining n bit planes, each bit plane contains the number and set of least significant bits ⁇ y
  • y 2 ji , i ⁇ j ⁇ n+i-1,j ⁇ Z ⁇ , the n values of y in one-to-one correspondence, adjust the driving current of the light source so that the light-emitting brightness of the light source is 2 i L. Since the number of
  • control device further includes a judgment on whether the increased bit depth number meets the preset life of the light source, and the steps include: assigning an initial value to the increased bit depth number; Rated current, rated output power, and rated current working temperature under continuous driving, calculate the aging acceleration factor of the light source under the current overshoot state; calculate the luminous brightness of the light source according to the initial bit depth of the display device and the increased bit depth
  • the time duty ratio is 2 i L; according to the statistical life of the light source under the continuous driving state of the rated current, as well as the aging acceleration factor and the time duty ratio, the statistical life of the light source under the current overshoot state is calculated; the judgment under the current overshoot state Whether the statistical life of the light source is greater than or equal to the preset life threshold, if yes, output the currently increased bit depth number; if not, reduce the increased bit depth number by one.
  • calculating the aging acceleration factor of the light source in the current overshoot state includes the following steps: The increased bit depth and the rated output power of the light source are calculated to obtain the power acceleration factor; the current acceleration factor is calculated according to the rated current of the light source and the driving current of the light source in the current overshoot state; the current acceleration factor is calculated according to the work of the light source in the continuous driving state of the rated current. The temperature and the working temperature of the light source in the current overshoot state obtain a temperature acceleration factor; and according to the power acceleration factor, current acceleration factor and temperature acceleration factor, the aging acceleration factor is obtained.
  • control device is also used to sort the bit planes of the grayscale image, which includes the following steps: according to the time ratio of the bit plane and the change rule of the brightness weight, determine whether the bit plane is a linear bit plane or an exponential bit plane. Plane; re-label the linear bit planes according to the order in which they are arranged in the linear bit plane, and arrange all linear bit planes in a manner of increasing or decreasing brightness weight, or in a staggered arrangement of increasing sequence and decreasing sequence, to obtain The first sequence; re-label the exponent bit planes according to their arrangement order in the exponent bit plane, and divide one or more adjacent least significant bits in each exponent bit plane into a group, and group all the exponent bits All the groups of the plane are arranged to obtain the second sequence, wherein the multiple group intervals of each exponential bit plane are distributed in the second sequence; and according to the group number of the first sequence and the second sequence, the sequence with the smaller number of groups Evenly insert into another sequence with a larger number of groups, or according to
  • determining whether the bit plane is a linear bit plane or an exponential bit plane according to the time ratio of the bit plane and the change rule of the brightness weight includes: arranging all the bit planes in the order of increasing brightness weight. If the weights are the same, they are arranged in the order of increasing the time proportion of each bit plane. After the arrangement, if the time length corresponding to each bit plane remains unchanged or increases by the same integer compared to the adjacent bit plane, the multiple The bit plane is a linear bit plane; and if the time length corresponding to each bit plane in multiple bit planes is increased by 2 g times compared to the adjacent bit plane, where g is a positive integer, the multiple bit planes are exponential Bit plane.
  • dividing one or more adjacent least significant bits in each exponential bit plane into a group includes: when the number of least significant bits in an exponent bit plane is not an integer multiple of the minimum time unit At the time, the supplementary least significant bit is added to the exponent bit plane so that the number of least significant bits of the exponent bit plane reaches an integer multiple of the minimum time unit.
  • a sequence with a smaller number of groups is uniformly inserted into another sequence with a larger number of groups, or according to the number of groups of the first sequence and the second sequence.
  • the number of groups if the number of groups is the same, after the first sequence and the second sequence are evenly interleaved with each other, it also includes: deleting all the supplementary least significant bits to obtain the third sequence. This method is helpful to avoid the increase in the number of least significant bits required in a single frame after the introduction of the supplementary least significant bits, which leads to an increase in the display time of a frame of image, and it is also beneficial to avoid a decrease in the maximum average display brightness within a frame time.
  • the light modulator corresponding to the supplementary least significant bit is placed in the "off" state.
  • the display device further includes: for all groups containing the supplementary least significant bit, arranging the supplementary least significant bit of each group at the same end of the group; when a group containing the supplementary least significant bit is located When the plane label is odd, the group containing the supplementary least significant bit is placed at one end of the bit plane; when the bit plane label of a group containing the supplementary least significant bit is even, the group containing the supplementary least significant bit is placed Place it on the other end of the bit plane.
  • the display device provided by the present invention uses the light source current overshoot method to increase the peak brightness of the display device to increase the display bit depth. At the same time, this method can increase the maximum average display brightness and shorten the display time of a single frame image.
  • the display device provided by the present invention The bit depth, brightness, and lifetime are also considered comprehensively; the display device provided by the present invention also optimizes the time control of the bit plane, so that the bit plane and its corresponding brightness display are more evenly distributed within a frame time, which is beneficial to avoid display Flicker phenomenon in.
  • FIG. 1 is a schematic diagram of the arrangement of pixels numbered 1 to 4.
  • Figure 2 is a schematic diagram of the principle of bit splitting.
  • FIG. 3 is a schematic diagram of the modulation mode of the light source and the light modulator provided by the first embodiment of the present invention.
  • 4 to 7 are modulation flowcharts of the light source and the light modulator provided by the first embodiment of the present invention.
  • FIG. 8 is a schematic diagram of the modulation mode of the light source and the light modulator provided by the second embodiment of the present invention.
  • FIG. 9 is a modulation flowchart of the light source and the light modulator provided by the second embodiment of the present invention.
  • FIG. 10 is a schematic diagram of the time control principle of the display device within one frame of image time according to the third embodiment of the present invention.
  • FIG. 11 is a schematic diagram of the time control principle of the display device within one frame of image time according to the fourth embodiment of the present invention.
  • 12a and 12b are schematic diagrams of the time control principle of the display device within one frame of image time according to the fifth embodiment of the present invention.
  • FIG. 13 is a schematic diagram of the time control principle of the display device within one frame of image time according to the sixth embodiment of the present invention.
  • FIG. 14 is a schematic diagram of the principle of the display device provided in the seventh embodiment of the present invention within one frame of image time.
  • the display device provided by the present invention uses the light source current overshoot method to increase the peak brightness of the display device to increase the display bit depth. At the same time, this method can increase the maximum average display brightness and shorten the display time of a single frame image.
  • the display device provided by the present invention A solution that comprehensively considers bit depth, brightness, and life is also proposed; the display device provided by the present invention also optimizes the time control of the bit plane, so that the bit plane and its corresponding brightness display are more evenly distributed within one frame. , Which helps avoid flickering in the display.
  • the display device proposed by the present invention may be, for example, a theater projector, an engineering projector, a micro projector, a laser TV, and other display products.
  • the first embodiment of the present invention provides a display device 10 based.
  • the display device 10 includes a light source; a light modulator, including a digital micro-mirror array including a plurality of micro-mirrors, is arranged on the light path of the light source from the light source, and is used to control the light source according to the target image and the brightness of the light source.
  • the display bit depth of the grayscale image is increased from n to n+i (i ⁇ 1 and i is an integer), and each period corresponds to the bit plane of the grayscale image one-to-one.
  • the light source includes multiple lasers, which emit laser light as illumination light.
  • the light source may also be a light emitting diode.
  • current overshoot refers to the use of overshoot pulse current to improve the brightness of the laser, where the driving current used exceeds the rated current of the laser.
  • the rated current refers to the maximum current that allows the laser to work stably for a long time.
  • the light modulator includes a digital micro-mirror array including a plurality of micro-mirrors, and the micro-mirrors are set at different angles to control the reflection direction of incident light.
  • the "on" state of the micro-mirror corresponds to modulating the emitted light from the light source to form image light and projected to the display device;
  • the "off” state of the micro-mirror corresponds to reflecting the emitted light from the light source to the off-display device At this time, the emitted light of the light source is non-image light.
  • each bit in it can be regarded as representing a binary plane, also called a bit plane.
  • Each bit plane contains one or more least significant bits, so the time length corresponding to the bit plane is the time length corresponding to the total least significant bits contained in it.
  • the least significant bit is a common concept in micro-mirrors, which refers to the smallest gray scale unit that can be achieved by micro-mirrors.
  • FIG. 3 is a schematic diagram of one of the modulation modes of the light source and the light modulator according to the first embodiment of the present invention.
  • 4 to 7 are modulation flowcharts of the light source and the light modulator provided by the first embodiment of the present invention.
  • the control device is used to control the driving current of the light source, so that the luminous brightness of the light source is adjusted in a period of time within one frame of image time and the driving current of the light source is overshooted in at least part of the period, including the following steps:
  • the gray-scale image includes n+i bit planes. When i bit planes are displayed, each bit plane contains only one least significant bit. Adjust the driving current of the light source to make the brightness of the light source and the set ⁇ k
  • k 2 j L, 0 ⁇ j ⁇ i-1, j ⁇ Z ⁇ has a one-to-one correspondence with i values of k, where L is a preset brightness parameter.
  • the display bit depth of the grayscale image is increased from 5 to 8 bits, and the bit plane is also increased from 5.
  • the control device divides the luminous brightness of the laser into 8 segments for adjustment.
  • these 3 bit planes respectively contain 1 least significant bit, and the corresponding laser luminous brightness is L, 2L, and 4L; the remaining 5 bit planes, respectively, contain 1, 2, 4 One, eight, and 16 least significant bits, corresponding to the laser's luminous brightness of 8L.
  • the light modulator is used to modulate the emitted light of the light source according to the target image and the luminous brightness of the light source, including:
  • the grayscale image includes n+i bit planes.
  • the modulation duration of the light modulator corresponds to the number of least significant bits contained in the bit plane.
  • the display bit depth of the grayscale image is increased from 5 to 8 bits, and the bit plane is also increased from 5.
  • the control device divides the light-emitting brightness of the laser into 8 segments for adjustment.
  • these 3 bit planes respectively contain 1 least significant bit, and the corresponding laser light intensity is L, 2L and 4L. If you want to display the brightness as L, control the micro mirror to display these 3
  • the switch states are “on”, “off”, and “off”.
  • the modulation duration of the micro-mirror is the duration of 1 least significant bit; when displaying the remaining 5 bit planes, each bit plane contains 1, 2 One, four, eight, and 16 least significant bits, corresponding to the laser's luminous brightness of 8L, if you want to display 32L, control the micro-mirror to display these 5 bit planes when the switch states are "off” and “off” , “On", “Off”, and “Off”, that is, keep the state of the micro-mirror as "on” within the 4 least significant bit duration contained in the bit plane.
  • FIG. 3 is only a special case of Embodiment 1 of the present invention.
  • the present invention does not limit the arrangement of bit planes.
  • the set of gray values can be realized as ⁇ 0,1,2,3,...,2 n+i -1 ⁇ L, and the gray value of the corresponding pixel of the micro mirror is 0.
  • the current overshoot method is used to increase the peak brightness of the display device to increase the display bit depth.
  • the time required to achieve n+i bit display in the rated current continuous drive mode is (2 n+i -1 ) t LSB , where t LSB is the duration of displaying a single least significant bit.
  • the display device provided in the embodiment of the present invention needs to display n+i digits for a duration of (2 n +i-1) t LSB , and the required time is about Rated current is 1/2 i in continuous drive mode. Therefore, the display device provided by the embodiment of the present invention is beneficial to shorten the display time of a single frame.
  • the beneficial effects of shortening the display time of a single frame include: high frame rate can be achieved, more intermediate states of the picture can be seen in the same time, and the moving picture is smoother and more natural; further, in single or dual film In the system of the display chip, the high frame rate means that the rotation of different colors can be made faster, so the rainbow phenomenon can be greatly alleviated; in addition, because the single frame display time is shortened, the original single frame display time is available To display images of different viewing angles to achieve 3D light field.
  • the maximum average display brightness of the image display that can be achieved within one frame time in this embodiment is:
  • the light-emitting brightness of the laser in this embodiment is 2 i times that under the continuous driving of the rated current, which is beneficial to improve the maximum average display brightness of the display device.
  • the control device provided by the present invention further includes a judgment on whether the increased bit depth number meets the preset life of the light source, and the steps include:
  • the aging acceleration state has an aging acceleration factor ⁇ , that is, under the aging acceleration condition, the statistical life of the laser is about 1/ ⁇ of the rated current continuous drive state.
  • step S22 further includes step S221, step S222, and step S223.
  • the laser output power P LD in the current overshoot state can be calculated.
  • P LD 2 i P norm .
  • the power acceleration factor ⁇ P can be calculated.
  • ⁇ is called the derating exponent and is related to the material of the laser.
  • step S222 can be omitted to reduce the amount of calculation, and the current acceleration factor ⁇ I is directly assigned a value of 1.
  • the temperature acceleration factor ⁇ T can be calculated, in which E A is the thermal activation energy (thermal activation energy), which generally ranges from 0.2 eV to 0.7 eV, and k B is the Boltzmann constant.
  • the luminous brightness of the light source is calculated to be 2 i L time duty ratio
  • S25 Determine whether the statistical lifetime ⁇ LD of the light source in the current overshoot state is greater than or equal to a preset lifetime threshold.
  • the statistical life of the laser under the continuous driving state of rated current is 30000 hours. Now it is necessary to use the laser current overshoot method as much as possible Increase the display bit depth, and the product required life (preset life threshold) is not less than 5000 hours.
  • the thermal activation energy E A 0.3eV
  • the time duty ratio of the light source's luminous brightness is calculated to be 2 i L Then the statistical life of the laser in the current overshoot state Therefore, the current overshoot will make the statistical life of the laser lower than the required life of the product (the preset life threshold).
  • the display device provided by the first embodiment of the present invention needs to adjust the laser brightness stepwise, for example, the laser brightness is adjusted to L during the first LSB, and the laser brightness is adjusted to 2L during the second LSB. Adjust the LSB to 4L..., the laser needs to adjust various brightness in a short period of time, and the current-brightness response curve of the laser may drift due to environmental factors such as temperature during operation, making the laser appear
  • the brightness display is unstable.
  • a less-brightness state (such as two display states of L and 4L) is used in one frame time, and there is no need to frequently adjust the light-emitting brightness of the laser in a short time. This method is more conducive to the light-emitting of the laser Stability of brightness.
  • the main difference between the display device provided by the second embodiment of the present invention and the first embodiment is that the luminous brightness of the laser in this embodiment only includes two digital states (L and 2 i L).
  • FIG. 8 is a schematic diagram of the modulation method of the light source and the light modulator provided by the second embodiment of the present invention.
  • the control device adjusts the brightness of the light source in a period of time within one frame of image and overshoots the driving current of the light source during at least part of the period, including the following steps: the grayscale image includes n+i bit planes.
  • each bit plane contains the number and set of least significant bits ⁇ y
  • y 2 ji , i ⁇ j ⁇ n+i-1,j ⁇ Z ⁇ has n values of y in one-to-one correspondence, adjust the driving current of the light source to make the light-emitting brightness of the light source 2 i L.
  • the light modulator is used to modulate the emitted light of the light source according to the target image and the luminous brightness of the light source, including the following steps: the grayscale image includes n+i bit planes, and when any one of the n+i bit planes is displayed , The modulation duration of the light modulator corresponds to the number of least significant bits contained in the bit plane.
  • the maximum average display brightness of the laser in this embodiment is higher than the maximum average display brightness of the laser under the continuous drive of the rated current, and the time required to complete the 2 n+i -bit gray scale display is also reduced from the original (2 n+i- 1) t LSB becomes the current (2 n +2 i -2) t LSB , which also shortens the single frame display time.
  • the modulation mode of the light source and the light modulator shown in FIG. 8 is a special example of the second embodiment of the present invention, and the present invention does not limit the arrangement of bit planes.
  • the human eyes will not receive light for a long time interval, which will cause the image display to appear flickering, for example,
  • flickering for example,
  • the pixels display two gray values of [10000] and [01111] in sequence, "0" is connected in time in the second half of the previous frame and the first half of the next frame. Together, they occupy the time required to display the entire frame.
  • the human eye sees the displayed image, there will be an obvious sense of flicker, but in fact the grayscale difference of the two frames is only one LSB.
  • an optimized bit split algorithm is to split the least significant bit contained in each bit plane into several small time units, which are evenly distributed to In one frame time, the first line sequence shown in Figure 2 contains 5 bit planes in the image display with a bit depth of 5, and the 5 bit planes are sequentially numbered as 0, 1, 2, 3, 4. Bit plane 0 only displays the time of one least significant bit in time, and the other bit planes must display the time of at least 2 LSBs. Taking into account the load memory time and switching time of a single micro-mirror in the DMD, the minimum time unit (time segment) inside the high bit plane is set to the time of 2 LSBs, which we call a group here .
  • a display system with a bit depth of n can display 2 n -1 (odd number) LSBs in a single frame, and the middle LSB uses the data amplitude of bit plane 0, and the remaining 2 n -2 LSBs, so can display 2 n-1 -1 groups, in which 2 n-2 bit plane for displaying the groups n-1, i.e. with a set of one every two groups to display bit plane n-1; wherein the 2 n-3 to show the bit planes groups n-2, i.e. groups with each 22 bit planes to display a group of n-2; wherein the displaying the 20 bit planes groups 1, i.e. each of 2 n-1 One of the groups is used to display bit plane 1.
  • the second row sequence and the third row sequence in Figure 2 are the optimized sequences of [01111] and [11010] in the bit splitting algorithm respectively.
  • the bit plane represented by the dotted line corresponds to the "0" in the binary system.
  • the light modulator In the "off”state; the bit plane represented by the solid line corresponds to the "1" in the binary system, and the light modulator is in the "on” state at this time.
  • this bit splitting algorithm optimizes the distribution of the bit plane under the condition that the luminous brightness of the light source is constant, so it is not suitable for the situation where the luminous brightness of the light source changes.
  • this bit split algorithm different time accounting bit planes in accordance with the exponential variation (duration, such as bit plane 0 corresponds to two 0 the LSB, bit plane when the length of a corresponding 2 1 the LSB), can not be directly applied.
  • the time proportion in the bit plane includes both linear changes (for example, each bit plane from bit plane 0 to bit plane i corresponds to 1 LSB) and exponential changes.
  • the bit plane arrangement order in the first embodiment is arbitrary, and in the first embodiment a special bit plane arrangement (such as Figure 3) A situation that may cause flickering in the human eye observation screen.
  • the third embodiment of the present invention optimizes the time control allocation of the bit plane, so that the bit plane time The plane and its corresponding brightness display are more evenly distributed, reducing the possibility of flickering that may cause the human eye to observe the picture.
  • the method for controlling the control device of the display device provided in this embodiment includes the following steps:
  • S31 Determine whether the bit plane is a linear bit plane or an exponential bit plane according to the change law of the time proportion of the bit plane and the brightness weight, including:
  • the bit plane judging whether the bit plane is a linear bit plane or an exponential bit plane, including: arranging all bit planes in the order of increasing brightness weight. If the brightness weight is the same, follow each The time proportions of the bit planes are arranged in an increasing order, and if the time length corresponding to each bit plane remains unchanged or increases by the same integer compared to the adjacent bit planes, the multiple bit planes are linear bit planes; And if among the multiple bit planes, the time length corresponding to each bit plane is increased by 2 g times compared to the adjacent bit plane, where g is a positive integer, then the multiple bit planes are exponential bit planes.
  • the display bit depth of the grayscale image is increased from 5 to 8 bits, and the bit plane is also increased from 5.
  • the bit plane is also increased from 5.
  • these 3 bit planes respectively contain 1 least significant bit, and the corresponding laser luminous brightness is L, 2L, and 4L; the remaining 5 bit planes, respectively, contain 1, 2, 4 One, eight, and 16 least significant bits, corresponding to the laser's luminous brightness of 8L.
  • Step S32 is performed for linear bit planes, and step S33 is performed for exponential bit planes.
  • S32 Re-label the linear bit planes according to their arrangement order in the linear bit plane, and arrange all linear bit planes in a manner of increasing or decreasing brightness weight, or arranged in a staggered manner in an increasing sequence and a decreasing sequence to obtain the first A sequence.
  • the first sequence can be obtained by arranging all linear bit planes in any order.
  • S33 Re-label the exponent bit planes according to the order in the exponent bit plane and divide one or more adjacent least significant bits in each exponent bit plane into a group, and group all the groups of all exponent bit planes The arrangement is performed to obtain a second sequence, wherein a plurality of group intervals of each exponential bit plane are distributed in the second sequence.
  • n bit planes are exponential bit planes
  • m adjacent LSBs in the same exponent bit plane are put in a group to obtain the second sequence.
  • 1 ⁇ m ⁇ n and m is an integer
  • n 4, m may be 1, 2, 3, or 4, for example. It should be understood that the examples are for illustrative convenience only, and the present invention does not limit the number of LSBs in a group
  • S34 According to the number of groups of the first sequence and the second sequence, evenly insert a sequence with a smaller number of groups into another sequence with a larger number of groups or according to the number of groups of the first sequence and the second sequence, if the number of groups is If they are the same, insert the first sequence and the second sequence at intervals.
  • every second sequence with a larger number of groups Groups are sequentially inserted into a group in the first sequence with a smaller number of groups, where It is a function of rounding down the real number X, but because in some cases, such as the number of LSBs contained in some groups in the second sequence is lower than the set minimum time unit, when counting the number of groups in the second sequence, The number of groups containing the number of LSBs lower than the set minimum time unit is not included in the calculation.
  • the linear bit planes are re-labeled according to the order of their arrangement in the linear bit plane, respectively marked as (0), (1), (2), the three linear bit planes are incremented according to the brightness weight Arranged to form the first sequence; in other embodiments, all linear bit planes can also be arranged in decreasing order of brightness weight or staggered according to the height of brightness weight. In an embodiment, if the brightness weights of the multiple linear bit planes are the same, the multiple linear bit planes in the first sequence can be arranged arbitrarily.
  • each group includes 2 adjacent LSBs.
  • bit plane 0 contains one LSB, which alone becomes a group; bit plane 1 contains two LSBs, and the two LSBs are combined into a group, which corresponds to bit plane 0 Adjacent arrangement; bit plane 2 contains 4 LSBs, which can form 2 groups, the group formed by combining bit plane 0 and bit plane 1 as a whole is inserted between the 2 groups of bit plane 2, forming a group containing 3 groups (Bit plane 0 and bit plane 1 are regarded as 1 group); bit plane 3 contains 8 LSBs, which can form 4 groups, and the 3 groups formed by combining bit plane 2, bit plane 1, and bit plane 0 are respectively Inserted between the 4 groups of bit plane 3 at intervals to form a sequence of 7 groups; bit plane 4 contains 16 LSBs, which can form 8 groups, and 7 groups are formed by combining bit plane 0 to bit plane 3. The groups are inserted at intervals between the 8 groups of bit plane 4 to form a second sequence containing 15
  • bit plane 0 only contains 1 group, and this group contains only one LSB, which is lower than the set minimum time unit, so the calculation will not It is included in the second sequence group number, and when the first sequence is inserted into the second sequence, bit plane 0 is not counted as a group alone.
  • bit plane 0 is not counted as a group alone.
  • the above method is not the only arrangement of linear bit planes and exponential bit planes. The arrangement mainly considers that exponential bit planes should be more evenly distributed in time, and the exponential bit planes and linear bit planes are in time. Can get more even distribution.
  • the linear bit planes (0), (1), (2) are respectively moved forward by 5 groups in the second sequence for insertion (bit plane 0 and bit plane 1 are regarded as 1 group).
  • the main difference between the display device provided in the fourth embodiment of the present invention and the third embodiment is that the exponential bit plane contains more least significant bits, so the total number of groups is reduced, and the number of loadings is also reduced.
  • Linear bit planes, respectively marked as (0), (1), (2), constitute the first sequence; in this embodiment, there are 5 exponential bit planes, respectively marked as 0, 1, 2, 3, 4, which constitute The second sequence; 4 adjacent LSBs in the exponent bit plane are combined into a group.
  • bit plane 0 contains one LSB, and the one LSB alone becomes a group; arranged in sequence The middle; bit plane 1 contains 2 LSBs, the 2 LSBs are combined into a group, considering the time required for the memory loading process, so a group of bit plane 0 and bit plane 1 using another index bit plane is divided .
  • Bit plane 2 contains 4 LSBs, which can form a group. A group corresponding to bit plane 2 can be inserted between bit plane 0 and bit plane 1.
  • Bit plane 3 contains 2 groups, which can be bit plane 0 ⁇ bit The sequence composed of plane 2 is inserted as a whole between the two groups of bit plane 3 to form a sequence containing 3 groups (the group corresponding to bit plane 0 to bit plane 2 is regarded as one group); bit plane 4 contains 4 groups, the 3 group intervals corresponding to bit planes 0 to 3 can be inserted between the 4 groups of bit plane 4 to obtain the second sequence, and bit plane 0 and bit plane 1 are regarded as 1 group and bit plane respectively. Seeing plane 2 as two groups, there are 9 groups of LSB in the second sequence.
  • bit plane 0 only contains 1 group and this group contains only one LSB, which is lower than the set minimum time unit
  • bit plane 1 only contains 1 group and this group only contains 2 LSBs, which is lower than the set minimum time unit. Therefore, it is not included in the second sequence group number for calculation.
  • the groups contained in bit plane 0 and bit plane 1 in the second sequence are also not individually regarded as a group.
  • the main difference between the display device provided in the fifth embodiment of the present invention and the third embodiment is that the number of LSBs (ie, the minimum time unit) of each group in the exponential bit plane is an odd number, because each exponent bit plane generally contains 2 n LSBs (n is a positive integer), so the number of LSBs in each exponent bit plane may not be divisible by the minimum time unit m.
  • bit plane 0 contains one LSB, which is placed in the middle of the second sequence
  • bit plane 1 contains 2 LSBs, put together into a group, considering the time required for the memory loading process, so It is separated from the memory loading of bit plane 0, and separates a group of bit plane 0 and bit plane 1 using another exponential bit plane.
  • bit planes 2, 3, and 4 contain 4, 8, and 16 LSBs respectively, which are not divisible by 3. Therefore, 2 supplementary LSBs can be added to bit plane 2 to make the number of LSBs of bit plane 2 reach the minimum time unit 2 times of 3, bit plane 3 can add 1 supplementary LSB to make the number of LSBs of bit plane 3 reach 3 times the minimum time unit 3, bit plane 4 can add 2 supplementary LSBs to minimize the number of LSBs of bit plane 4 6 times the time unit 3; in other words, for each bit plane, 2 or 1 LSB needs to be supplemented so that the number of LSBs in each bit plane is an integer multiple of 3. After that, bit plane 0 to bit plane 4 can be arranged in the same manner as in Embodiment 3 to obtain the second sequence.
  • the supplementary LSB corresponds to the clear operation of the DMD, that is, all micro-mirrors are set to the "off" state, so that the supplementary LSB corresponds to the dark state in its time series, so black is used to indicate the supplement in Figure 12a. LSB.
  • supplementary LSB has no corresponding light modulation process.
  • Such a design is beneficial to avoid the increase in the number of LSBs required in a single frame after the introduction of supplementary LSBs, which leads to an increase in the display duration of one frame of image, and it is also beneficial to avoid a decrease in the maximum average display brightness within a frame.
  • the main difference between the display device provided by the sixth embodiment of the present invention and the third embodiment is that when the number of linear bit planes is equal to the number of exponential bit planes, according to the principle of homogenization, the first sequence and the second sequence The evenly staggered arrangement can meet the requirements.
  • the number of linear bit planes and the number of exponential bit planes are the same. According to the principle of homogenization, the first sequence and the second sequence are uniformly staggered to meet the requirement.
  • the main difference between the display device provided in the seventh embodiment of the present invention and the second embodiment is that: on the basis of the second embodiment, when the two types of luminous brightness are designed with exponential bit planes, the first sequence and the second sequence The sequences are divided and arranged according to the bit plane and then inserted and arranged at intervals.
  • the display bit depth with a luminance of 2 i L is 5, and it contains 5 bit planes, which are marked as bit planes 0, 1, 2, 3, 4, and a total of 31 LSBs. Therefore, it can follow the traditional bit planes.
  • the method of splitting is combined and arranged, as shown in Figure 14; similarly, the display bit depth with a luminance of L is 5 and contains 5 bit planes, which are marked as bit planes (0), (1), (2).
  • bit plane (0) corresponding to a single LSB is placed behind the center Position, and the single LSB corresponding to bit plane 0 is placed in front of the center.
  • linear bit plane 0 and exponential bit plane 0 are placed adjacently , It makes the micro-mirror in the internal "off" state more in local time. After obtaining the first sequence and the second sequence, uniformly cross-mix them to achieve uniform brightness.
  • the fast time response characteristics of the laser are used to improve the peak brightness of the display device through current overshoot, so that the time required for bit depth modulation can be reduced to less by controlling the driving current of the laser in the current overshoot state.
  • the current overshoot avoids the problem of lowering the average brightness of the image caused by the traditional technology to increase the display bit depth.
  • the present invention reduces the time response requirements of the optical modulator by adjusting the driving current of the laser in the current overshoot state and combining multiple LSBs.
  • the present invention adjusts the current within the time corresponding to each LSB, because the laser
  • the pulse modulation time is relatively fast, which can be above 100kHz or even higher. At this stage, there is no restriction on the time response of the optical modulator, so a high frame rate can be achieved.
  • the display device provided by the present invention also comprehensively considers the bit depth, brightness and life and improves the display bit depth; the display device provided by the present invention also optimizes the time control of the bit plane so that the bit plane and its corresponding The brightness display is more evenly distributed, which helps to avoid flicker in the display.

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Abstract

本发明提供的显示设备包括光源；光调制器，包括包含多个微反射镜的数字微镜阵列，设置在光源的出射光的光路上，用于根据目标图像及所述光源的发光亮度对所述光源的出射光进行调制，得到灰度图像；以及控制装置，用于控制所述光源的驱动电流，使得在一帧图像时间内分时段调节所述光源的发光亮度，并在至少部分时段使所述光源的驱动电流过冲，以将所述灰度图像的显示位深由n增加为n+i(i≥1且i为整数)，且每一所述时段与所述灰度图像的位平面一一对应。

Description

显示设备 技术领域
本发明涉及显示技术领域，尤其涉及一种显示设备。
背景技术
基于数字微镜阵列(如DMD，Digital Micromirror Device)的图像显示中，图像的显示位深与DMD的翻转时间(crossover time)和切换时间(switching time)相关。翻转时间一般为1～3微秒，为微反射镜从一个状态翻转到另外一个状态所需要的时间。切换时间，一般超过10微秒，为单个微反射镜从一次状态变化到另外一次连续的变化所需要的时间。切换时间相比翻转时间多出的时间为微反射镜稳定的抖动时间。理论而言，切换时间决定了在一帧图像内单个微反射镜的翻转次数，因而也决定了图像的显示位深。
现有的技术中常用的实现高位深的方法主要有DMD的清零操作(clear operation)，DMD的抖动(Dithering)和光源的光强调制。
清零操作可使所有微反射镜无需等待稳定抖动时间即可统一回到“关”(“off”)状态，因此采用清零操作可使得切换时间缩短为翻转时间，以提高图像的显示位深。但由于镜片有效处于“开”(“on”)状态的时间减少，图像显示的最大平均亮度会减弱，且增加的位深越多，图像显示的平均亮度降低得越多。
DMD的抖动可分为空间抖动和时间抖动。举例而言，空间上相邻的像素，如果在一个显示周期中仅有一半的像素亮，如图1所示，编号分别为1、2、3、4的四个相邻的像素中，像素1和像素4亮，或者像素2和像素3亮，则当像素足够小或者人眼离屏幕距离足够远时，人眼看到的这四个像素的平均亮度是单个像素可以显示的最小亮度的一半。另外，还可利用时间抖动使得DMD相邻的像素相互轮转地显 示，例如，使上述四个像素在四个图像帧时间内轮循显示，可在实现更小的亮度单元的同时避免显示画面出现重复的图案。DMD的抖动是通过降低图像显示的最小亮度单元来提高位深的，同时也牺牲了图像显示的最大平均亮度。
光源的光强调制的原理是在最低有效位(Least Significant Bit，LSB)对应的时间内，降低光源的光强，以实现更低的灰度显示。例如，在LSB对应的时间内，若将光源的发光强度调为原来的
Figure PCTCN2020090758-appb-000001
则LSB对应的亮度变为原来的
Figure PCTCN2020090758-appb-000002
此时图像的位显示深增加了4位。光源的光强调制也是以牺牲图像显示的最大平均亮度来实现图像显示位深的增加。
综上所述，现有技术均通过降低最低亮度实现高位深，使得欲显示图像暗部细节得以体现，但是上述方法均导致图像显示的最大平均亮度降低，且在投影***所处环境光亮度较高时，低亮度区间增加的灰度细节会被环境光所掩盖。
发明内容
本发明提供一种显示设备，能够解决现有显示设备显示位深提高有限，且一帧时间内最大平均显示亮度降低的问题。
本发明采用一个技术方案是：光源；光调制器，包括包含多个微反射镜的数字微镜阵列，设置在光源的出射光的光路上，用于根据目标图像及光源的发光亮度对光源的出射光进行调制，得到灰度图像；以及控制装置，用于控制光源的驱动电流，使得在一帧图像时间内分时段调节光源的发光亮度，并在至少部分时段使光源的驱动电流过冲，以将灰度图像的显示位深由n增加为n+i(i≥1且i为整数)，且每一时段与灰度图像的位平面一一对应。
在一种实施方式中，根据目标图像及光源的发光亮度对光源的出射光进行调制包括：灰度图像包括n+i个位平面，当显示n+i个位平面的任意一个位平面时，光调制器的调制时长与该位平面包含的最低有效位个数相对应。
在一种实施方式中，在一帧图像时间内分时段调节光源的发光亮度，并在至少部分时段使光源的驱动电流过冲包括如下步骤：灰度图像包括n+i个位平面，在显示其中的i个位平面时，每个位平面只包含1个最低有效位，调节光源的驱动电流使得光源的发光亮度与集合{k|k＝2 jL,0≤j≤i-1,j∈Z}中k的i个数值一一对应，其中L为预设亮度参数；以及在显示其余的n个位平面时，每个位平面包含的最低有效位的个数与集合{m|m＝2 j-i,i≤j≤n+i-1,j∈Z}中m的n个数值一一对应，调节光源的驱动电流使得光源的发光亮度为2 iL。通过光源与光调制器的结合使用，可实现显示设备的显示位深数增加；有利于缩短单帧显示时间，实现高帧率；另外有利于提高一帧时间内可实现的图像显示的最大平均显示亮度。
在一种实施方式中，在一帧图像时间内分时段调节光源的发光亮度，并在至少部分时段使光源的驱动电流过冲包括如下步骤：灰度图像包括n+i个位平面，在显示其中i个位平面时，每个位平面包含的最低有效位的个数与集合{x|x＝2 j,0≤j≤i-1,j∈Z}中x的i个数值一一对应，调节光源的驱动电流使得光源的发光亮度为L，其中L为预设亮度参数；以及在显示其余的n个位平面时，每个位平面包含最低有效位的个数与集合{y|y＝2 j-i,i≤j≤n+i-1,j∈Z}中y的n个数值一一对应，调节光源的驱动电流使得光源的发光亮度为2 iL。由于光源的发光亮度状态数减少，有利于提高显示设备的稳定性。
在一种实施方式中，控制装置还包括对增加的位深数是否满足光源的预设寿命的判断，步骤包括：对增加的位深数赋予一个初始值；根据增加的位深数和光源的额定电流、额定输出功率、额定电流连续驱动下的工作温度，计算得到电流过冲状态下光源的老化加速因子；根据显示设备的初始位深数和增加的位深数，计算得到光源的发光亮度为2 iL的时间占空比；根据额定电流连续驱动状态下光源的统计寿命，及老化加速因子和时间占空比，计算得到电流过冲状态下光源的统计寿命；判断电流过冲状态下光源的统计寿命是否大于等于预设寿命阈值，若是，则输出当前增加的位深数；若否，则使增加的位深数 减少一位。
在一种实施方式中，根据增加的位深数和光源的额定电流、额定输出功率、额定电流连续驱动下的工作温度，计算得到电流过冲状态下光源的老化加速因子，包括如下步骤：根据增加的位深数和光源的额定输出功率，计算得到功率加速因子；根据光源的额定电流和电流过冲状态下光源的驱动电流，计算得到电流加速因子；根据额定电流连续驱动状态下光源的工作温度以及电流过冲状态下光源的工作温度，得到温度加速因子；以及根据功率加速因子、电流加速因子和温度加速因子，得到老化加速因子。
在一种实施方式中，控制装置还用于对灰度图像的各位平面进行排序，包括如下步骤：根据位平面的时间占比和亮度权重的变化规律，判断位平面属于线性位平面还是指数位平面；对线性位平面按照其在线性位平面的排列顺序进行重新标号，并将所有线性位平面按照亮度权重依次递增或递减的方式排列，或按照递增序列与递减序列交错排列的方式排列，得到第一序列；对指数位平面按照其在指数位平面中的排列顺序进行重新标号，并将每个指数位平面中相邻的一个或多个最低有效位分为一个组，并将所有指数位平面的所有组进行排列得到第二序列，其中每个指数位平面的多个组间隔分布于第二序列中；以及根据第一序列和第二序列的组数，将组数较少的一个序列均匀***到另外一个组数较多的序列中，或根据第一序列和第二序列的组数，若组数相同，则将第一序列和第二序列相互均匀交错排列。通过这种排列方式，使得在一帧时间内位平面及其对应的亮度显示得到较为均匀的分配，有利于避免显示中的闪烁现象。
在一种实施方式中，根据位平面的时间占比和亮度权重的变化规律，判断位平面属于线性位平面还是指数位平面，包括：将所有位平面按照亮度权重依次增加的顺序排列，若亮度权重相同，则按照每个位平面的时间占比依次增加的顺序排列，排列后若每个位平面对应的时间长度相比相邻的位平面保持不变或以同一整数增加，则该多个位平面为线性位平面；以及若多个位平面中，每个位平面对应的时间长 度相比相邻的位平面以2 g倍增加，其中g为正整数，则该多个位平面为指数位平面。
在一种实施方式中，将每个指数位平面中相邻的一个或多个最低有效位分为一个组，包括：当一个指数位平面中最低有效位的数目不为最小时间单元的整数倍时，在指数位平面中添加补充最低有效位以使指数位平面的最低有效位的数目达到最小时间单元的整数倍。
在一种实施方式中，根据第一序列和第二序列的组数，将组数较少的一个序列均匀***到另外一个组数较多的序列中，或根据第一序列和第二序列的组数，若组数相同，则将第一序列和第二序列相互均匀交错排列之后，还包括：删除所有补充最低有效位，得到第三序列。这种方式有利于避免因引入补充最低有效位之后单帧中需要的最低有效位数目增加导致一帧图像的显示时长增加，同时也有利于避免一帧时间内最大平均显示亮度降低。
在一种实施方式中，补充最低有效位对应的光调制器置于“关”状态。
在一种实施方式中，显示设备还包括：对于所有含有补充最低有效位的组，将每组的补充最低有效位排在该组的同一端；当一个含有补充最低有效位的组所在的位平面标号为奇数时，该含有补充最低有效位的组放在所处的位平面的一端；当一个含有补充最低有效位的组所在的位平面标号为偶数时，该含有补充最低有效位的组放在所处的位平面的另一端。
本发明提供的显示设备利用光源电流过冲的方式来提高显示设备的峰值亮度从而提高显示位深，同时此方式可提高最大平均显示亮度及缩短单帧图像的显示时间，本发明提供的显示设备还综合考虑了位深、亮度和寿命；本发明提供的显示设备还优化了位平面的时间控制，使得在一帧时间内位平面及其对应的亮度显示得到较为均匀的分配，有利于避免显示中的闪烁现象。
附图说明
为了更清楚地说明本发明实施例/方式技术方案，下面将对实施例/方式描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图是本发明的一些实施例/方式，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1为编号为1至4的像素的排列示意图。
图2为位拆分的原理示意图。
图3为本发明第一实施例提供的光源及光调制器的调制方式示意图。
图4至图7为本发明第一实施例提供的光源及光调制器的调制流程图。
图8为本发明第二实施例提供的光源及光调制器的调制方式示意图。
图9为本发明第二实施例提供的光源及光调制器的调制流程图。
图10为本发明第三实施例提供的显示设备在一帧图像时间内的时间控制原理示意图。
图11为本发明第四实施例提供的显示设备在一帧图像时间内的时间控制原理示意图。
图12a和图12b为本发明第五实施例提供的显示设备在一帧图像时间内的时间控制原理示意图。
图13为本发明第六实施例提供的显示设备在一帧图像时间内的时间控制原理示意图。
图14为本发明第七实施例提供的显示设备在一帧图像时间内的原理示意图。
主要元件符号说明
Figure PCTCN2020090758-appb-000003
如下具体实施方式将结合上述附图进一步说明本发明。
具体实施方式
为了能够更清楚地理解本发明的上述目的、特征和优点，下面结合附图和具体实施例对本发明进行详细描述。需要说明的是，在不冲突的情况下，本申请的实施例及实施例中的特征可以相互组合。
在下面的描述中阐述了很多具体细节以便于充分理解本发明，所描述的实施例仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。
除非另有定义，本文所使用的所有的技术和科学术语与属于本发明的技术领域的技术人员通常理解的含义相同。本文中在本发明的说明书中所使用的术语只是为了描述具体的实施例的目的，不是旨在于限制本发明。
本发明提供的显示设备利用光源电流过冲的方式来提高显示设备的峰值亮度从而提高显示位深，同时此方式可提高最大平均显示亮度及缩短单帧图像的显示时间，本发明提供的显示设备还提出了一种综合考虑位深、亮度和寿命的方案；本发明提供的显示设备还优化了位平面的时间控制，使得在一帧时间内位平面及其对应的亮度显示得到较为均匀的分配，有利于避免显示中的闪烁现象。本发明提出的显示设备可例如为影院投影机、工程投影机、微型投影仪、激光电视等显示产品中。
第一实施例
本发明第一实施例提供一种基于显示设备10。其中，显示设备10包括光源；光调制器，包括包含多个微反射镜的数字微镜阵列，设置在光源的出射光的光路上，用于根据目标图像及光源的发光亮度对光源的出射光进行调制，得到灰度图像；以及控制装置，用于控制光源的驱动电流，使得在一帧图像时间内分时段调节光源的发光亮度，并在至少部分时段使光源的驱动电流过冲，以将灰度图像的显示位深由n增加为n+i(i≥1且i为整数)，且每一时段与灰度图像的位 平面一一对应。
本实施例中，光源包括多个激光器，发出激光作为照明光。在其它实施例中，光源还可为发光二极管。具体地，电流过冲(overdrive pulse)指的是利用过冲的脉冲电流提高激光器的亮度，其中所使用的驱动电流超过了激光器的额定电流。其中，额定电流指的是使激光器能够长期稳定地工作所允许通过的最大电流。
光调制器，包括包含多个微反射镜的数字微镜阵列，微反射镜通过设置不同角度，以控制对入射光的反射方向。一般而言，微反射镜的“开”状态对应将光源的出射光进行调制，形成图像光，并投射至显示装置；微反射镜的“关”状态对应将光源的出射光反射至偏离显示装置的区域，此时光源的出射光为非图像光。
除此以外，我们知道计算机之所以能够显示颜色，是采用了一种称作“比特”的记数单位来记录所表示颜色的数据。对于显示位深为8比特的图像而言，最大灰度值为2 8＝256。对一幅用比特表示其灰度值的图像来说，其中的每个比特可看作表示了1个二值的平面，也称位平面。每个位平面包含一个或多个最低有效位，因此位平面对应的时间长度为其所包含的总的最低有效位对应的时间长度。最低有效位是微反射镜中的一个常用概念，是指微反射镜能够实现的最小灰度单位，举例说明，假设微反射镜对应的显示区域能实现2 8＝256种灰度状态，除了全暗的[00000000]状态外，[00000001]为能够调制的最小亮度单元，也是相邻的两个灰阶的灰度差，为实现该亮度，微反射镜处于“开”状态的时长即为最低有效位对应的时长。
具体地，请参阅图3-图7，图3为本发明第一实施例提供的光源及光调制器的调制方式之一的示意图。图4-图7为本发明第一实施例提供的光源及光调制器的调制流程图。
S11：控制装置用于控制光源的驱动电流，使得在一帧图像时间内分时段调节光源的发光亮度并在至少部分时段使光源的驱动电流过冲，包括如下步骤：
S111：灰度图像包括n+i个位平面，在显示其中的i个位平面时，每个位平面只包含1个最低有效位，调节光源的驱动电流使得光源的 发光亮度与集合{k|k＝2 jL,0≤j≤i-1,j∈Z}中k的i个数值一一对应，其中L为预设亮度参数。
S112：在显示其余的n个位平面时，每个位平面包含的最低有效位的个数与集合{m|m＝2 j-i,i≤j≤n+i-1,j∈Z}中m的n个数值一一对应，调节光源的驱动电流使得光源的发光亮度为2 iL。
举例而言，当显示设备的原显示位深n＝5且需增加的位深数i＝3时，则灰度图像的显示位深由5位增加为8位，位平面也从5个增加为8个。由于每一时段与灰度图像的一个位平面图像数据相对应，因此控制装置对激光器的发光亮度分成8段进行调节。在显示其中3个位平面，这3个位平面分别包含1个最低有效位，对应激光器的发光亮度为L、2L和4L；其余5个位平面，分别位平面包含1个、2个、4个、8个、16个最低有效位，对应激光器发光亮度为8L。
S12：光调制器用于根据目标图像及光源的发光亮度对光源的出射光进行调制，包括：
灰度图像包括n+i个位平面，当显示n+i个位平面的任意一个位平面时，光调制器的调制时长与该位平面包含的最低有效位个数相对应。
举例而言，当显示设备的原显示位深n＝5且需增加的位深数i＝3时，则灰度图像的显示位深由5位增加为8位，位平面也从5个增加为8个。由于每一时段与灰度图像的一个位平面图像数据相对应，因此控制装置对激光器的发光亮度分成8段进行调节。在显示其中3个位平面，这3个位平面分别包含1个最低有效位，对应激光器的发光亮度为L、2L和4L，若欲显示亮度为L，则控制微反射镜在显示这3个位平面时开关状态分别为“开”、“关”、“关”，微反射镜的调制时长为1个最低有效位的时长；在显示其余5个位平面，分别位平面包含1个、2个、4个、8个、16个最低有效位，对应激光器发光亮度为8L，若欲显示32L，则控制微反射镜在显示这5个位平面时开关状态分别为“关”、“关”、“开”、“关”、“关”，即在该位平面包含的4个最低有效位时长内，保持微反射镜的状态为“开”。
应理解，图3仅为本发明实施例1的一种特殊情况。本发明不限制位平面的的排列方式。
通过光源和光调制器的配合，可以实现灰度值的集合为{0,1,2,3,…,2 n+i-1}L，微反射镜全关对应像素的灰度值为0的情形，微反射镜全开对应像素的灰度值为(1+2 1+2 2+…+2 i-1)L+(2 n-1)2 iL＝(2 n+i-1)L的情形。
本实施例中通过电流过冲方式来提高显示设备的峰值亮度从而提高显示位深，另一方面，额定电流连续驱动模式下实现n+i位显示所需的时间为(2 n+i-1)t LSB，其中t LSB为显示单个最低有效位时长，本发明实施例提供的显示设备实现n+i位显示所需时长为(2 n+i-1)t LSB，所需的时间约为额定电流连续驱动模式时的1/2 i。因此，本发明实施例提供的显示设备有利于缩短单帧显示时长。缩短单帧显示时间带来的有益效果包括：可实现高帧率，在相同的时间内可以看到画面更多的中间状态，使运动的画面更流畅自然；进一步地，在单片或双片显示芯片的***中，高帧率意味着可使不同颜色的轮转变得更快，因此，彩虹现象可得到较大缓解；除此以外，由于单帧显示时间缩短，原来显示单帧的时间可用于显示不同视角的图像，从而实现3D光场。
除此以外，相比传统的降低显示的最低亮度来提高显示位深的方法，本实施例中一帧时间内可实现的图像显示的最大平均显示亮度为：
Figure PCTCN2020090758-appb-000004
由此可见，本实施例中激光器的发光亮度为额定电流连续驱动下的2 i倍，有利于提高显示设备的最大平均显示亮度。
随着增加的位深数i的取值的增大，激光器处于电流过冲的时间也随之增加，激光器的寿命可能会受到一定的影响，因此在考虑应用时，需要综合考虑位深的增加、亮度的提升以及寿命的影响几个方面，进一步确定增加的位深数i的取值。具体地，请参阅图6，本发明提供的控制装置还包括对增加的位深数是否满足光源的预设寿命的判断，步骤包括：
S21：对增加的位深数i赋予一个初始值。
S22：根据增加的位深数i和光源的额定电流I norm、额定输出功率P norm、额定电流连续驱动下的工作温度T norm，计算得到电流过冲状态下光源的老化加速因子π。
具体地，对于毫秒量级的长脉冲，使用N倍(约5倍)额定驱动电流对于激光器寿命的影响主要来自于渐变老化，值得指出的是，电流过冲驱动的限制主要在激光器的散热。在保持激光器结温低于最高工作温度的情况下，若将激光器与散热器之间的热阻减半，原则上N可以更大。老化加速状态相比于额定电流连续驱动状态存在一个老化加速因子π，即在老化加速条件下，激光器统计寿命约为额定电流连续驱动状态下的1/π。一般情况下，老化加速因子π会受到激光器的工作温度(发光腔体的温度)T LD、激光器的输出功率P LD和激光器的驱动电流I LD的影响，即π＝π(T LD,P LD,I LD)。其中π(T LD,P LD,I LD)可表示为温度加速因子π T、功率加速因子π P和电流加速因子π I的乘积，即π＝π(T LD,P LD,I LD)＝π Tπ Pπ I。请参阅图7，步骤S22还包括步骤S221、步骤S222和步骤S223。
S221：根据增加的位深数i和光源的额定输出功率P norm，计算得到功率加速因子π P。
具体地，根据增加的位深数i和激光器的额定输出功率P norm，可计算得到电流过冲状态下激光器输出功率P LD。本实施例中，P LD＝2 iP norm。根据额定电流连续驱动状态下激光器输出功率P norm和电流过冲状态下激光器输出功率P LD，可计算得到功率加速因子π P，本实施例中，
Figure PCTCN2020090758-appb-000005
其中β称为减少指数(derating exponent)，与激光器的材料有关。
S222：根据光源的额定电流I norm和电流过冲状态下激光器的驱动电流I LD，计算得到电流加速因子π I。
本实施例中，
Figure PCTCN2020090758-appb-000006
由于激光器的驱动电流与输出功率和 激光器温度直接相关，一般x取值为0，因此π I一般取值为1。在一种实施例中，步骤S222可省略以减少计算量，并直接给电流加速因子π I赋值为1。
S223：根据额定电流连续驱动状态下光源的工作温度T norm以及电流过冲状态下光源的工作温度T LD，得到温度加速因子π T。
具体地，根据
Figure PCTCN2020090758-appb-000007
可计算得到温度加速因子π T，其中E A是热激活能(thermal activation energy)一般取值为0.2eV到0.7eV，k B是玻尔兹曼常数。
S224：根据功率加速因子π T、电流加速因子π I和温度加速因子π P，得到老化加速因子π＝π(T LD,P LD,I LD)＝π Tπ Pπ I。
S23：请再参阅图6，根据显示设备的初始位深数n和增加的位深数i，计算得到光源的发光亮度为2 iL的时间占空比。
本实施例中，计算得到光源的发光亮度为2 iL的时间占空比
Figure PCTCN2020090758-appb-000008
Figure PCTCN2020090758-appb-000009
S24：根据额定电流连续驱动状态下光源的统计寿命λ norm、老化加速因子π和时间占空比D on，计算得到电流过冲状态下光源的统计寿命λ LD。
S25：判断电流过冲状态下光源的统计寿命λ LD是否大于等于预设寿命阈值。
若是，则输出当前增加的位深数i；若否，则使i＝i-1，即使增加的位深数i减少一位，再重复执行步骤S22-步骤S25，直至电流过冲状态下激光器的统计寿命λ LD大于等于预设寿命阈值。
为方便理解上述步骤，下面举一个例子来具体说明：
假设正常的额定电流照明情况下通过控制光调制器可以实现n＝8位显示，激光器在额定电流连续驱动状态下能使用的统计寿命为30000小时，现在需要通过使用激光器电流过冲的方法尽可能提高显 示位深，而且产品要求寿命(预设寿命阈值)不小于5000小时。
现考虑将显示设备的显示位深由n位增加至n+2位，即增加的位深数i＝2，可以初步考虑提高激光器电流过冲状态下的驱动电流I LD以使得激光器的输出功率P LD变为额定电流连续驱动状态下激光器的输出功率P norm的2 i＝2 2＝4倍。假设减少指数β＝2，则可计算得到功率加速因子
Figure PCTCN2020090758-appb-000010
另外一方面，由于激光器的散热基板之间存在热阻，输出功率的增大会导致产热的增多，进而导致激光器温度由额定电流连续驱动状态下的工作温度T norm＝273+35＝308K升高到T LD＝273+55＝328K，假设热激活能E A＝0.3eV，则温度加速因子
Figure PCTCN2020090758-appb-000011
Figure PCTCN2020090758-appb-000012
因此老化加速因子π＝π(T LD,P LD,I LD)＝π Tπ Pπ I＝2×16×1＝32。
由于n＝8，i＝2，计算得到光源的发光亮度为2 iL的时间占空比
Figure PCTCN2020090758-appb-000013
Figure PCTCN2020090758-appb-000014
则电流过冲状态下激光器的统计寿命
Figure PCTCN2020090758-appb-000015
Figure PCTCN2020090758-appb-000016
因此电流过冲会使得激光器的统计寿命低于产品要求寿命(预设寿命阈值)。
为了提高电流过冲状态下激光器的统计寿命λ LD，现将增加的位深数减少一位，即i＝1，提高激光器在电流过冲状态下的驱动电流I LD以使得激光器的输出功率变为额定电流连续驱动状态下激光器的额定输出功率的2 1＝2倍，则功率加速因子
Figure PCTCN2020090758-appb-000017
激光器的工作温度由额定电流连续驱动状态下的温度T norm＝273+35＝308K升高到T LD＝273+45＝318K，则可计算得到温度加速因子
Figure PCTCN2020090758-appb-000018
Figure PCTCN2020090758-appb-000019
老化加速因子π＝ π(T LD,P LD,I LD)＝π Tπ Pπ I＝1.43×4×1＝5.72，在电流过冲状态下的时间占空比
Figure PCTCN2020090758-appb-000020
电流过冲状态下激光器的统计寿命为
Figure PCTCN2020090758-appb-000021
故增加的位深数i＝1时激光器的统计寿命可以满足产品的寿命要求，因此可以通过电流过冲的方式实现8+1＝9位的显示位深且激光器满足大于5000h的使用寿命。举例仅为说明方便，本发明不限定增加的位深数。
第二实施例
由于本发明第一实施例提供的显示设备需要对激光器亮度进行阶梯式调节，例如在第一个LSB的时间将激光器亮度调节为L，第二个LSB的时间将激光器亮度调节为2L，第三个LSB的时间将LSB调节为4L……，激光器需要在短时间内进行多种亮度调节，且激光器在运行的过程中可能由于温度等环境因素导致其电流-亮度响应曲线发生漂移，使得激光器出现亮度显示不稳定的问题。本发明第二实施例中在一帧时间内采用较少亮度状态(如L、4L两种显示状态)，而无需在短时间内频繁调节激光器的发光亮度，这种作法更有利于激光器的发光亮度的稳定性。
本发明第二实施例提供的显示设备与第一实施例的主要区别在于：本实施例中激光器的发光亮度仅包括两种数字状态(L和2 iL)。
请参阅图8，图8为本发明第二实施例提供的光源及光调制器的调制方式示意图。相比于第一实施例，控制装置在一帧图像时间内分时段调节光源的亮度并在至少部分时段使光源的驱动电流过冲包括如下步骤：灰度图像包括n+i个位平面，在显示其中i个位平面时，每个位平面包含的最低有效位的个数与集合{x|x＝2 j,0≤j≤i-1,j∈Z}中x的i个数值一一对应，调节光源的驱动电流使得光源的发光亮度为L，其中L为预设亮度参数；以及在显示其余的n个位平面时，每个位平面包含最低有效位的个数与集合{y|y＝2 j-i,i≤j≤n+i-1,j∈Z}中y的n个数值一一对应，调节光源的驱动电流使得光源的发光亮度为2 iL。
光调制器，用于根据目标图像及光源的发光亮度对光源的出射光 进行调制包括如下步骤：灰度图像包括n+i个位平面，当显示n+i个位平面的任意一个位平面时，光调制器的调制时长与该位平面包含的最低有效位个数相对应。
本实施例中一帧时间内可实现的图像显示的最大平均显示亮度为：
Figure PCTCN2020090758-appb-000022
即本实施例中激光器的最大平均显示亮度较额定电流连续驱动下激光器最大平均显示亮度有所提高，而完成2 n+i位灰度显示所需要的时间也由原来的(2 n+i-1)t LSB变为现在的(2 n+2 i-2)t LSB，同样也缩短了单帧显示时间。
另外，光源的发光亮度为2 iL的时间占空比时间占比为D on＝(2 n-1)/(2 i-1+2 n-1)。
应理解，图8所示的的光源及光调制器的调制方式为本发明第二实施例的一个特例，本发明不限制位平面的排列方式。
第三实施例
若时间上某一时段内DMD的微反射镜处于“关”状态的时间较长时，人眼在较长的时间间隔内接收不到光会导致图像显示出现闪烁(flickering)的现象，例如在相邻的两个图像帧内，当像素依次显示[10000]和[01111]两个灰度值时，“0”在前一帧的后半帧和后一帧的前半帧在时间上连在一起而占据显示整个帧所需的时间，当人眼看到的显示图像上会出现明显的闪烁感，而实际上两帧的灰度只相差一个LSB。
因此,针对上述闪烁问题，一种优化的位拆分(bit split)算法是将每个位平面(bit plane)中的包含的最低有效位拆分成若干个小的时间单元，均匀地分散到一帧时间中，如图2所示的第一行序列，在位深为5的图像显示中含有5个位平面，图中对该5个位平面依次编号为0,1,2,3,4。位平面0在时间上只显示一个最低有效位的时间，其余的位平面都要显示至少2个LSB的时间。考虑到DMD中单个微反射镜 操作时装载内存(load memory)时间及切换时间，将高位位平面内部的最小时间单元(time segment)定为2个LSB的时间，这里我们称为组(group)。具体来讲，位深为n的显示***，单帧中可以显示2 n-1(奇数)个LSB，将中间的一个LSB使用位平面0的数据幅值，剩余2 n-2个LSB，因此可以显示2 n-1-1个组，将其中2 n-2个组用于显示位平面n-1，即每2 1个组中用一个组来显示位平面n-1；将其中的2 n-3个组来显示位平面n-2，即每2 2个组中用一个组来显示位平面n-2；将其中的2 0个组来显示位平面1，即每2 n-1个组中用一个组来显示位平面1。图2中的第二行序列和第三行序列分别为[01111]和[11010]在位拆分算法优化后的序列，其中虚线表示的位平面对应二进制中的“0”，此时光调制器处于“关”状态；实线表示的位平面对应二进制中的“1”，此时光调制器处于“开”状态。
然而，该位拆分算法是针对光源的发光亮度恒定情况下对位平面的分布做优化，因此不适用于光源的发光亮度变化的情况。此外，该位拆分算法中不同的位平面的时间占比是按照指数形式变化(如位平面0的时长对应2 0个LSB，位平面1的时长对应2 1个LSB)，也不能直接应用于位平面的时间占比同时包含线性形式变化(如位平面0至位平面i中每个位平面都对应1个LSB)和指数形式变化的情形。
本发明第三实施例提供的显示设备与第一实施例的主要区别在于：第一实施例中位平面排列顺序是任意的，在第一实施例的一种特殊的位平面的排列方式(如图3)可能导致人眼观测画面出现闪烁的情况，在第一实施例提出的显示设备的基础上，本发明第三实施例对位平面的时间控制分配进行优化，使得在一帧时间内位平面及其对应的亮度显示得到较为均匀的分配，减少可能导致人眼观测画面出现闪烁的可能性。具体地，请参阅图9，本实施例提供的显示设备的控制装置的控制方法包括如下步骤：
S31：根据位平面的时间占比和亮度权重的变化规律，判断位平面属于线性位平面还是指数位平面，包括：
根据位平面的时间占比和亮度权重的变化规律，判断位平面属于 线性位平面还是指数位平面，包括：将所有位平面按照亮度权重依次增加的顺序排列，若亮度权重相同，则按照每个位平面的时间占比依次增加的顺序排列，排列后若每个位平面对应的时间长度相比相邻的位平面保持不变或以同一整数增加，则该多个位平面为线性位平面；以及若多个位平面中，每个位平面对应的时间长度相比相邻的位平面以2 g倍增加，其中g为正整数，则该多个位平面为指数位平面。
举例而言，当显示设备的原显示位深n＝5且需增加的位深数i＝3时，则灰度图像的显示位深由5位增加为8位，位平面也从5个增加为8个。在显示其中3个位平面，这3个位平面分别包含1个最低有效位，对应激光器的发光亮度为L、2L和4L；其余5个位平面，分别位平面包含1个、2个、4个、8个、16个最低有效位，对应激光器发光亮度为8L。将所有位平面按照亮度权重依次增加的顺序排列，则按照激光器的发光亮度为L、2L和4L对3个位平面按照发光亮度依次增加的顺序进行排列；若亮度权重相同，则按照每个位平面的时间占比依次增加的顺序排列，因此其余的5个位平面，对应激光器发光亮度为8L，按照位平面包含最低有效位个数从少到多对位平面进行排序。最终排序结果如图3所示。
针对线性位平面执行步骤S32，针对指数位平面执行步骤S33。
S32：对线性位平面按照其在线性位平面的排列顺序进行重新标号并将所有线性位平面按照亮度权重依次递增或递减的方式排列，或按照递增序列与递减序列交错排列的方式排列，得到第一序列。
可以理解，若亮度权重保持不变，则第一序列可由所有线性位平面按任意顺序排列所得到。
S33：对指数位平面按照其指数位平面中的排列顺序进行重新标号并将每个指数位平面中相邻的一个或多个最低有效位分为一个组，并将所有指数位平面的所有组进行排列得到第二序列，其中每个指数位平面的多个组间隔分布于第二序列中。
举例而言，n个位平面为指数位平面，则将同一个指数位平面中的相邻的m个LSB放在一个组，得到第二序列，优选地，1≤m≤n且 m为整数，例如，当n＝4时，m可例如为1、2、3或4。应理解，举例仅为说明方便，本发明不限定一组中LSB的个数
S34：根据第一序列和第二序列的组数，将组数较少的一个序列均匀***到另外一个组数较多的序列中或根据第一序列和第二序列的组数，若组数相同，则将第一序列和第二序列相互间隔***。
本实施例中，由于第二序列的组数多于第一序列的组数，因此在组数较多的第二序列中每隔
Figure PCTCN2020090758-appb-000023
个组依次***组数较少的第一序列中的一个组，其中
Figure PCTCN2020090758-appb-000024
是对实数X的向下取整函数，但由于在某些情况下，如第二序列中某些组中含有的LSB数目低于设置的最小时间单元，因此在统计第二序列组数时，含有的LSB数目低于设置的最小时间单元的组数不纳入计算。
举例而言，增加的位深数i＝3，显示设备的原显示位深n＝5，指数位平面中每个组的LSB数目(即最小时间单元)m＝2，因此本实施例中存在3个线性位平面，对线性位平面按照其在线性位平面的排列顺序进行重新标号，分别标记为(0)、(1)、(2)，该3个线性位平面按亮度权重递增的方式排列，组成第一序列；在其他实施例中，所有线性位平面还可按亮度权重递减或按亮度权重的高低交错排列。在一种实施例中，若多个线性位平面的亮度权重相同，则第一序列中该多个线性位平面可任意排列。
本实施例中存在5个指数位平面，对指数位平面按照其指数位平面中的排列顺序进行重新标号，分别标记为0、1、2、3、4，组成第二序列；指数位平面内每个组包括2个相邻的LSB。
请参阅图10，5个指数位平面中，位平面0含有一个LSB，该一个LSB单独成为一个组；位平面1含有2个LSB，2个LSB组合为一个组，与位平面0对应的组相邻排列；位平面2含有4个LSB，可组成2个组，将位平面0和位平面1组合而成的组作为整体***到位平面2的2个组之间，形成一个含有3个组的序列(位平面0和位平面1视为1组)；位平面3含有8个LSB，可组成4个组，将位平面2、 位平面1和位平面0组合而成的3个组分别间隔地***位平面3的4个组之间，形成一个含有7个组的序列；位平面4含有16个LSB，可组成8个组，将位平面0～位平面3组合而成的7个组分别间隔地***位平面4的8个组之间，形成含有15个组的第二序列。将位平面0和位平面1拆分为2个组来看，则第二序列共有16组LSB。
由于第二序列的组数多于第一序列的组数，因此将第一序列均匀***到第二序列中，其中第二序列每隔
Figure PCTCN2020090758-appb-000025
个组按线性位平面的排列顺序***一个线性位平面，在计算时由于位平面0仅含有1组，且该组仅包含一个LSB，低于设置的最小时间单元，因此在进行计算时不将其纳入第二序列组数，且第一序列***第二序列时，不将位平面0单独算作一组。应理解，上述方式不是唯一的线性位平面和指数性位平面的排列方式，排列时主要考虑指数性位平面在时间上应可得到较均匀分配且指数性位平面和线性位平面之间在时间上可得到较均匀分配。本实施例的另一变形实施例中，线性位平面(0)、(1)、(2)分别向前移动5个第二序列中的组进行***(位平面0和位平面1视为1组)。
第四实施例
本发明第四实施例提供的显示设备与第三实施例的主要区别在于：指数位平面所包含的最低有效位的个数更多，因此组的总数目减少了，装载的次数也减少了。
本实施例中，增加的位深数i＝3，增加前的显示位深n＝5，指数位平面中每个组的LSB数目(最小时间单元)m＝4，因此本实施例中存在3个线性位平面，分别标记为(0)、(1)、(2)，组成第一序列；本实施例中存在5个指数位平面，分别标记为0、1、2、3、4，组成第二序列；指数位平面内的4个相邻的LSB组合成一个组。
请参阅图11，3个线性位平面(0)、(1)、(2)依次递增排列；5个指数位平面中，位平面0含有一个LSB，该一个LSB单独成为一个组；排在序列的中间；位平面1含有2个LSB，该2个LSB组合为一个组，考虑到内存装载过程需要的时间，因此将位平面0和位平面1之 间使用另外一个指数位平面的一个组分开。位平面2含有4个LSB，可组成1个组，可将位平面2对应的1个组***到位平面0和位平面1之间；位平面3含有2个组，可将位平面0～位平面2组成的序列作为整体***至位平面3的2个组之间，形成一个含有3个组的序列(将位平面0～位平面2对应的组视为1个组)；位平面4含有4个组，可将位平面0～3对应的3个组间隔***至位平面4的4个组之间，得到第二序列，将位平面0、位平面1分别视为1个组、位平面2视为2个组来看，则第二序列共有9组LSB。由于第二序列的组数大于第一序列的组数，故将第一序列均匀***到第二序列中且第二序列每隔
Figure PCTCN2020090758-appb-000026
个组按第一序列的组排列顺序***一个第一序列的1个组，即对应1个线性位平面。由于位平面0仅含有1组且该组仅包含一个LSB，低于设置的最小时间单元，同样，位平面1仅含有1组且该组仅包含2个LSB，低于设置的最小时间单元，因此在进行计算时不将其纳入第二序列组数进行计算。在进行***时，也不将第二序列中位平面0和位平面1所包含的组单独作为一组。应理解，上述方式不是唯一的线性位平面和指数性位平面的排列方式，排列时主要考虑指数性位平面在时间上应可得到较均匀分配且指数性位平面和线性位平面之间在时间上可得到较均匀分配。
第五实施例
本发明第五实施例提供的显示设备与第三实施例的主要区别在于：指数位平面中每个组的LSB数目(即最小时间单元)为奇数，由于每个指数位平面中一般包含2 n个LSB(n为正整数)，因此可能出现每个指数位平面的LSB个数不能被最小时间单元m整除的情况。
本实施例中，增加的位深数i＝3，原显示位深n＝5，指数位平面中每个组的LSB数目(最小时间单元)m＝3，因此本实施例中存在3个线性位平面，分别标记为(0)、(1)、(2)，组成第一序列，本实施例中存在5个指数位平面，分别标记为0、1、2、3、4，组成第二序列；每个指数位平面包括3个相邻的LSB。
请一并参阅图12a和图12b，将3个线性位平面(0)、(1)、(2)依次递增排列。5个指数位平面中，位平面0含有一个LSB，将其排在第二序列的中间，位平面1含有2个LSB，放在一起成为一个组，考虑到内存装载过程需要的时间，因此将其与位平面0的内存装载分开，将位平面0和位平面1中间使用另外一个指数位平面的一个组分开。
当一个指数位平面中最低有效位的数目不为最小时间单元的整数倍时，在该指数位平面中添加补充最低有效位以使该指数位平面的最低有效位的数目达到最小时间单元的整数倍。
另外位平面2、3、4中分别含有4个、8个和16个LSB，均不能被3整除，因此位平面2中可增加2个补充LSB以使位平面2的LSB数目达到最小时间单元3的2倍，位平面3可增加1个补充LSB以使位平面3的LSB数目达到最小时间单元3的3倍，位平面4可增加2个补充LSB以使位平面4的LSB数目达到最小时间单元3的6倍；换句话说，对于每个位平面，均需要补充2个或1个LSB以使得每个位平面中的LSB的数目是3的整数倍。之后，可按照与实施例3的方式对位平面0～位平面4进行排列得到第二序列。
对于补充LSB可以有两种方案来处理：
一种方案是将补充最低有效位对应的光调制器置于“关”状态。具体地，将补充LSB对应为DMD的清除(clear)操作，即将所有微反射镜均置为“关”状态，这样补充LSB对应其时间序列上总对应暗状态，因此图12a中采用黑色表示补充LSB。
由于一个位平面中可能会有多个组，因此如何将补充LSB在不同组之间和单个组中如何进行分配以及组之间的排列需要进一步的设计：对于所有含有补充最低有效位的组，将每组的补充最低有效位排在该组的同一端(如，末端)。当一个含有补充最低有效位的组所在的位平面被标记为奇数时，该含有补充最低有效位的组放在所处的位平面的一端(如，首端)；当一个含有补充最低有效位的组所在的位平面被标记为偶数时，该含有补充最低有效位的组放在所处的位平面的另一端(如，末端)。如此设计有利于避免清除操作在相邻的两个组中出现。
另外一种方案是，在将组数较少的一个序列均匀***到另外一个组数较多的序列中之后，删除所有补充最低有效位，得到第三序列，如图12b示。换句话说，补充LSB无对应的光调制过程。如此设计有利于避免因引入补充LSB之后单帧中需要的LSB数目增加导致一帧图像的显示时长增加，同时也有利于避免一帧时间内最大平均显示亮度降低。
第六实施例
本发明第六实施例提供的显示设备与第三实施例的主要区别在于：当线性位平面数目与指数性位平面个数相等的时候，按照均匀化的原则，将第一序列和第二序列相互均匀交错排列即可满足要求。
具体地，请参阅图13，本实施例中，增加的位深数i＝7，增加前的显示位深n＝3，指数位平面中每个组的LSB数目m＝1，因此本实施例中存在7个线性位平面，分别标记为(0)、(1)、(2)、(3)、(4)、(5)、(6)，组成第一序列；本实施例中存在3个指数位平面，分别标记为0、1、2，组成第二序列；由于m＝1，指数位平面内的每个LSB独立形成一个组，或者说没有组操作。这种情况下，线性位平面的数目和指数位平面的数目相同，按照均匀化的原则，第一序列和第二序列相互均匀交错排列即可满足要求。
第七实施例
本发明第七实施例提供的显示设备与第二实施例的主要区别在于：在第二实施例的基础上，当两种发光亮度均是采用指数位平面的设计时，第一序列和第二序列都按照位平面分割排列后再相互间隔***排列。
请参阅图14，本实施例中，增加的位深数i＝5，增加前的显示位深n＝5，指数位平面中每个组的LSB数目m＝2。本实施例中，发光亮度为2 iL的显示位深为5，含有5个位平面，分别标记为位平面0、1、2、3、4，总共31个LSB，因此可以按照传统的位拆分的方法进行组合并排列，如图14所示；类似地，发光亮度为L的显示位深为5，含有5个位平面，分别标记为位平面(0)、(1)、(2)、(3)、(4)，总共31个 LSB，因此可以按照传统的位拆分的方法进行组并排列，略微不同的是将对应单个LSB的位平面(0)放在中心偏后的位置，而位平面0对应的单个LSB放在中心偏前的位置。此步操作是由于考虑到当m＝2时单个组上装载内存所需的时间可能超过单个LSB的时间，因此需要进行“清除”操作，若将线性位平面0和指数位平面0相邻放置，则使得微反射镜在局部时间处于内“关”状态较多。得到第一序列和第二序列之后，均匀将其交叉混合即可实现均匀化的亮度。
本发明中利用激光器的快速时间响应特性，通过电流过冲提高显示设备的峰值亮度，这样可以通过控制激光器在电流过冲状态下的驱动电流从而将位深调制所需的时间压缩在更少个LSB的时间内，通过电流过冲避免了传统技术提高显示位深的同时带来的图像平均亮度降低的问题。需要指出的是，本发明通过调控激光器在电流过冲状态下的驱动电流并合并多个LSB来降低对光调制器的时间响应要求，本发明在每个LSB对应的时间内调控电流，由于激光器脉冲调制的时间较快，可以在100kHz以上甚至更高，现阶段对光调制器的时间响应没有限制，因此可以实现高帧率。
本发明提供的显示设备还综合考虑了位深、亮度和寿命并提高了显示位深；本发明提供的显示设备还通过优化位平面的时间控制，使得在一帧时间内位平面及其对应的亮度显示得到较为均匀的分配，有利于避免显示中的闪烁现象。
对于本领域技术人员而言，显然本发明不限于上述示范性实施例的细节，而且在不背离本发明的精神或基本特征的情况下，能够以其他的具体形式实现本发明。因此，无论从哪一点来看，均应将实施例看作是示范性的，而且是非限制性的，本发明的范围由所附权利要求而不是上述说明限定，因此旨在将落在权利要求的等同要件的含义和范围内的所有变化涵括在本发明内。不应将权利要求中的任何附图标记视为限制所涉及的权利要求。此外，显然“包括”一词不排除其他单元或步骤，单数不排除复数。装置权利要求中陈述的多个装置也可以由同一个装置或***通过软件或者硬件来实现。第一，第二等词语用 来表示名称，而并不表示任何特定的顺序。
最后应说明的是，以上实施例仅用以说明本发明的技术方案而非限制，尽管参照较佳实施例对本发明进行了详细说明，本领域的普通技术人员应当理解，可以对本发明的技术方案进行修改或等同替换，而不脱离本发明技术方案的精神和范围。

Claims (12)

  1. 一种显示设备，其特征在于，包括：
    光源；
    光调制器，包括包含多个微反射镜的数字微镜阵列，设置在光源的出射光的光路上，用于根据目标图像及所述光源的发光亮度对所述光源的出射光进行调制，得到灰度图像；以及
    控制装置，用于控制所述光源的驱动电流，使得在一帧图像时间内分时段调节所述光源的发光亮度，并在至少部分时段使所述光源的驱动电流过冲，以将所述灰度图像的显示位深由n增加为n+i(i≥1且i为整数)，且每一所述时段与所述灰度图像的位平面一一对应。
  2. 如权利要求1所述的显示设备，其特征在于，所述根据目标图像及所述光源的发光亮度对所述光源的出射光进行调制包括：
    所述灰度图像包括n+i个位平面，当显示n+i个位平面的任意一个位平面时，光调制器的调制时长与该位平面包含的最低有效位个数相对应。
  3. 如权利要求2所述的显示设备，其特征在于，所述在一帧图像时间内分时段调节所述光源的发光亮度，并在至少部分时段使所述光源的驱动电流过冲包括如下步骤：
    所述灰度图像包括n+i个位平面，在显示其中的i个位平面时，每个位平面只包含1个最低有效位，调节所述光源的驱动电流使得光源的发光亮度与集合{k|k＝2 jL,0≤j≤i-1,j∈Z}中k的i个数值一一对应，其中L为预设亮度参数；以及
    在显示其余的n个位平面时，每个位平面包含的最低有效位的个数与集合{m|m＝2 j-i,i≤j≤n+i-1,j∈Z}中m的n个数值一一对应，调节所述光源的驱动电流使得光源的发光亮度为2 iL。
  4. 如权利要求2所述的显示设备，其特征在于，所述在一帧图像时间内分时段调节所述光源的发光亮度，并在至少部分时段使所述光源的驱动电流过冲包括如下步骤：
    所述灰度图像包括n+i个位平面，在显示其中i个位平面时，每个位平面包含的最低有效位的个数与集合{x|x＝2 j,0≤j≤i-1,j∈Z}中x的i个数值一一对应，调节所述光源的驱动电流使得所述光源的发光亮度为L，其中L为预设亮度参数；以及
    在显示其余的n个位平面时，每个位平面包含最低有效位的个数与集合{y|y＝2 j-i,i≤j≤n+i-1,j∈Z}中y的n个数值一一对应，调节所述光源的驱动电流使得光源的发光亮度为2 iL。
  5. 如权利要求1所述的显示设备，其特征在于，所述控制装置还包括对增加的位深数是否满足所述光源的预设寿命的判断，步骤包括：
    对增加的位深数赋予一个初始值；
    根据所述增加的位深数和所述光源的额定电流、额定输出功率、额定电流连续驱动下的工作温度，计算得到电流过冲状态下所述光源的老化加速因子；
    根据所述显示设备的初始位深数和增加的位深数，计算得到光源的发光亮度为2 iL的时间占空比；
    根据额定电流连续驱动状态下所述光源的统计寿命，及所述老化加速因子和所述时间占空比，计算得到电流过冲状态下所述光源的统计寿命；
    判断电流过冲状态下所述光源的统计寿命是否大于等于预设寿命阈值，若是，则输出当前增加的位深数；若否，则使增加的位深数减少一位。
  6. 如权利要求5所述的显示设备，其特征在于，根据所述增加的位深数和所述光源的额定电流、额定输出功率、额定电流连续驱动下的工作温度，计算得到电流过冲状态下所述光源的老化加速因子，包括如下步骤：
    根据增加的位深数和所述光源的额定输出功率，计算得到功率加速因子；
    根据所述光源的额定电流和电流过冲状态下所述光源的驱动电流， 计算得到电流加速因子；
    根据额定电流连续驱动状态下所述光源的工作温度以及电流过冲状态下所述光源的工作温度，得到温度加速因子；以及
    根据所述功率加速因子、所述电流加速因子和所述温度加速因子，得到所述老化加速因子。
  7. 如权利要求1-6任意一项所述的显示设备，其特征在于，所述控制装置还用于对所述灰度图像的各位平面进行排序，包括如下步骤：
    根据位平面的时间占比和亮度权重的变化规律，判断位平面属于线性位平面还是指数位平面；
    对线性位平面按照其在线性位平面的排列顺序进行重新标号，并将所有线性位平面按照亮度权重依次递增或递减的方式排列，或按照递增序列与递减序列交错排列的方式排列，得到第一序列；
    对指数位平面按照其在指数位平面中的排列顺序进行重新标号，并将每个指数位平面中相邻的一个或多个最低有效位分为一个组，并将所有指数位平面的所有组进行排列得到第二序列，其中每个指数位平面的多个组间隔分布于第二序列中；以及
    根据第一序列和第二序列的组数，将组数较少的一个序列均匀***到另外一个组数较多的序列中，或
    根据第一序列和第二序列的组数，若组数相同，则将第一序列和第二序列相互均匀交错排列。
  8. 如权利要求7所述的显示设备，其特征在于，所述根据位平面的时间占比和亮度权重的变化规律，判断位平面属于线性位平面还是指数位平面，包括：将所有位平面按照亮度权重依次增加的顺序排列，若亮度权重相同，则按照每个位平面的时间占比依次增加的顺序排列，排列后若每个位平面对应的时间长度相比相邻的位平面保持不变或以同一整数增加，则该多个位平面为线性位平面；以及若多个位平面中，每个位平面对应的时间长度相比相邻的位平面以2 g倍增加，其中g为正整数，则该多个位平面为指数位平面。
  9. 如权利要求8所述的显示设备，其特征在于，所述将每个指数 位平面中相邻的一个或多个最低有效位分为一个组，包括：
    当一个指数位平面中最低有效位的数目不为最小时间单元的整数倍时，在所述指数位平面中添加补充最低有效位以使所述指数位平面的最低有效位的数目达到最小时间单元的整数倍。
  10. 如权利要求9所述的显示设备，其特征在于，所述根据第一序列和第二序列的组数，将组数较少的一个序列均匀***到另外一个组数较多的序列中，或根据第一序列和第二序列的组数，若组数相同，则将第一序列和第二序列相互均匀交错排列之后，还包括：
    删除所有补充最低有效位，得到第三序列。
  11. 如权利要求9所述的显示设备，其特征在于，所述补充最低有效位对应的光调制器置于“关”状态。
  12. 如权利要求9-11任一项所述的显示设备，其特征在于，所述显示设备还包括：
    对于所有含有补充最低有效位的组，将每组的补充最低有效位排在该组的同一端；
    当一个含有所述补充最低有效位的组所在的位平面标号为奇数时，该含有所述补充最低有效位的组放在所处的位平面的一端；当一个含有所述补充最低有效位的组所在的位平面标号为偶数时，该含有所述补充最低有效位的组放在所处的位平面的另一端。
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CN110809120B (zh) * 2019-11-01 2021-04-27 深圳创维－Rgb电子有限公司 拍摄画面的补光方法、智能电视及计算机可读存储介质
DE102021209454A1 (de) * 2021-08-27 2023-03-02 Osram Gmbh Verfahren zum Steuern einer Laserdiode sowie einer digitalen Mikrospiegelvorrichtung einer bilderzeugenden Einheit in einem holografischen Head-Up-Display
CN115810320B (zh) * 2023-02-08 2023-05-05 山东云海国创云计算装备产业创新中心有限公司 灰度图像显示的协同控制方法、***、设备及存储介质
CN117676107B (zh) * 2024-01-31 2024-05-24 武汉中观自动化科技有限公司 图像激光投影方法以及激光投影设备

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105991980A (zh) * 2015-02-06 2016-10-05 深圳市绎立锐光科技开发有限公司 投影***及其控制方法
CN106205451A (zh) * 2015-05-28 2016-12-07 乐金显示有限公司 图像处理电路、图像处理方法和使用其的显示装置
CN108538265A (zh) * 2016-03-31 2018-09-14 青岛海信移动通信技术股份有限公司 一种液晶显示屏的显示亮度调整方法及装置

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5461411A (en) * 1993-03-29 1995-10-24 Texas Instruments Incorporated Process and architecture for digital micromirror printer
US6930797B2 (en) * 2001-02-27 2005-08-16 Eastman Kodak Company Method and apparatus for printing high resolution images using multiple reflective spatial light modulators
JP3719411B2 (ja) * 2001-05-31 2005-11-24 セイコーエプソン株式会社 画像表示システム、プロジェクタ、プログラム、情報記憶媒体および画像処理方法
US7595811B2 (en) * 2001-07-26 2009-09-29 Seiko Epson Corporation Environment-complaint image display system, projector, and program
US6980321B2 (en) * 2001-08-20 2005-12-27 Eastman Kodak Company Method and apparatus for printing high resolution images using multiple reflective spatial light modulators
US6888657B2 (en) * 2003-01-28 2005-05-03 Hewlett-Packard Development Company, L.P. Multiple-bit storage element for binary optical display element
US8270061B2 (en) * 2003-11-01 2012-09-18 Silicon Quest Kabushiki-Kaisha Display apparatus using pulsed light source
US8432339B2 (en) * 2005-02-16 2013-04-30 Texas Instruments Incorporated System and method for increasing bit-depth in a video display system using a pulsed lamp
KR20070028892A (ko) * 2005-09-08 2007-03-13 엘지전자 주식회사 비트 깊이를 조정하는 디엘피 투사형 디스플레이 장치 및그 제어방법
US20140327885A1 (en) * 2013-05-01 2014-11-06 David Joseph Mansur Apparatus for obtaining enhanced contrast in projected images using digital micromirror devices
CN105467733B (zh) * 2014-08-25 2018-08-28 深圳市光峰光电技术有限公司 投影显示***及其控制方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105991980A (zh) * 2015-02-06 2016-10-05 深圳市绎立锐光科技开发有限公司 投影***及其控制方法
CN106205451A (zh) * 2015-05-28 2016-12-07 乐金显示有限公司 图像处理电路、图像处理方法和使用其的显示装置
CN108538265A (zh) * 2016-03-31 2018-09-14 青岛海信移动通信技术股份有限公司 一种液晶显示屏的显示亮度调整方法及装置

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