CN109597263B

CN109597263B - Imaging device and lens focusing method

Info

Publication number: CN109597263B
Application number: CN201710940346.3A
Authority: CN
Inventors: 袁炜军
Original assignee: Hangzhou Hikmicro Sensing Technology Co Ltd
Current assignee: Hangzhou Hikmicro Sensing Technology Co Ltd
Priority date: 2017-09-30
Filing date: 2017-09-30
Publication date: 2024-03-08
Anticipated expiration: 2037-09-30
Also published as: CN109597263A

Abstract

The embodiment of the invention provides an imaging device and a lens focusing method, wherein the imaging device comprises: the device comprises a focusing wheel, two photoelectric sensors, at least three gratings, a processor, a motor component and a lens, wherein the gratings are distributed on the inner side wall of the focusing wheel, and gaps with equal width exist between adjacent gratings. The processor firstly determines a first electric signal generated by the first photoelectric sensor and a second electric signal generated by the second photoelectric sensor; then, according to the first electric signal and the second electric signal, determining the current rotation direction of the focusing wheel based on a preset parameter table; and finally, determining the current rotation angle of the focusing wheel according to the level jump number of the first electric signal or the second electric signal, wherein the level jump of the first electric signal or the second electric signal comprises the jump from high level to low level and the jump from low level to high level. The embodiment of the invention can realize manual focusing of the lens by utilizing the photoelectric sensor.

Description

Imaging device and lens focusing method

Technical Field

The present invention relates to the field of information processing technologies, and in particular, to an imaging apparatus and a lens focusing method.

Background

In practical applications, the focusing mode of the infrared lens configured on the handheld infrared thermal imaging device includes automatic focusing and manual focusing.

Currently, a relatively wide manual focusing manner is implemented by using a mechanical gear connection device, specifically, referring to fig. 1, fig. 1 is a schematic structural diagram of a focusing device for implementing focusing by using mechanical gear connection in an imaging apparatus in the prior art. As shown in fig. 1, when the mechanical focusing wheel 101 is rotated, the mechanical focusing wheel 101 is meshed with a gear of the adapter ring 102 and a pin 103 fixed on the cam 104 is used to drive the cam 104 to rotate in the circumferential direction, and then the positioning pin 105 is used to drive the focusing lens barrel 106 to move back and forth along the axial direction, so as to realize manual focusing.

Although the infrared lens can be focused by the mode, the gear transmission device has the advantages of large number of parts, high processing precision, complex transmission among gears, high processing cost and high difficulty, and cannot meet the requirement of mass production.

Disclosure of Invention

The embodiment of the invention provides imaging equipment and a lens focusing method, which are used for realizing manual focusing of a lens by utilizing a photoelectric sensor and a grating. The specific technical scheme is as follows:

An embodiment of the present invention provides an imaging apparatus including: the device comprises a focusing wheel, two photoelectric sensors, at least three gratings, a processor, a motor component and a lens, wherein the gratings are distributed on the inner side wall of the focusing wheel, and tooth gaps with equal width exist between adjacent gratings;

a processor for determining a first electrical signal generated by the first photosensor;

a processor for determining a second electrical signal generated by a second photosensor; wherein the first electrical signal is generated when the first photoelectric sensor passes through the grating, and the second electrical signal is generated when the second photoelectric sensor passes through the grating;

the processor is used for determining the current rotation direction of the focusing wheel based on a preset parameter table according to the first electric signal and the second electric signal, wherein the parameter table comprises the corresponding relation between the first electric signal and the second electric signal and the preset rotation direction of the focusing wheel;

and the processor is used for determining the current rotation angle of the focusing wheel according to the level jump number of the first electric signal or the second electric signal, wherein the level jump of the first electric signal or the second electric signal comprises the jump from high level to low level and the jump from low level to high level.

Optionally, the processor is further configured to determine a focusing direction of the lens according to the first parameter configuration of the lens and the current rotation direction of the focusing wheel;

determining the focusing distance of the lens according to the second parameter configuration of the lens and the current rotation angle of the focusing wheel;

the motor part focuses the lens based on the focusing direction of the lens and the focusing distance of the lens.

Optionally, the current rotation angle of the focusing wheel is equal to the level jump number multiplied by a tooth period included angle, wherein the tooth period included angle is an included angle corresponding to a tooth period on the inner side wall of the focusing wheel, and the tooth period is the sum of the width of one grating and the width of one tooth gap.

Optionally, the imaging device further comprises a fixing piece, and the two photoelectric sensors are mounted on the fixing piece;

the parameter table also comprises a preset phase difference between the positions of the two photoelectric sensors on the fixing piece;

when two photoelectric sensors are mounted on the fixing piece, the current phase difference between the positions of the two photoelectric sensors on the fixing piece accords with the preset phase difference, wherein the current phase difference is calculated according to the tooth period included angle and the included angle between the positions of the two photoelectric sensors on the fixing piece.

Optionally, the parameter table includes a correspondence between five continuous level signals of the first electrical signal, five continuous level signals of the second electrical signal corresponding to the first electrical signal, and a preset rotation direction of the focusing wheel.

Optionally, the parameter table includes: when the first electric signal comprises a low level, a high level, a low level and a low level in time sequence in the first time period, and the corresponding second electric signal comprises the low level, the high level and the low level in the first time period, the corresponding focusing wheel preset rotation direction is clockwise;

when the first electric signal comprises a low level, a high level and a low level in time sequence in the second time period, and the corresponding second electric signal comprises the low level, the high level, the low level and the low level in the second time period, the corresponding focusing wheel preset rotation direction is anticlockwise;

the first photoelectric sensor passes through the grating when the focusing wheel rotates, and the second photoelectric sensor passes through the grating after the focusing wheel rotates.

Optionally, the first parameter configuration includes a configuration relationship between a rotation direction of the focusing wheel and a focusing direction of the lens, and when the rotation direction of the focusing wheel is clockwise or counterclockwise, the focusing direction of the lens is moved along the axial direction.

Optionally, the second parameter configuration includes a focusing distance by a rotational angle of the focusing wheel and the lens, wherein the focusing distance of the lens is determined by the rotational angle of the focusing wheel and a parameter of a motor component of the lens.

The embodiment of the invention also provides a lens focusing method which is applied to the imaging equipment, wherein the imaging equipment comprises the following steps: the method comprises the following steps of focusing wheels, two photoelectric sensors, at least three gratings, a processor, a motor component and a lens, wherein the gratings are distributed on the inner side walls of the focusing wheels, and tooth gaps with equal widths exist between adjacent gratings, and the method comprises the following steps:

determining a first electrical signal generated by a first photosensor;

determining a second electrical signal generated by a second photosensor;

wherein the first electrical signal is generated when the first photoelectric sensor passes through the grating, and the second electrical signal is generated when the second photoelectric sensor passes through the grating;

determining the current rotation direction of the focusing wheel based on a preset parameter table according to the first electric signal and the second electric signal, wherein the parameter table comprises the corresponding relation between the first electric signal and the second electric signal and the preset rotation direction of the focusing wheel;

and determining the current rotation angle of the focusing wheel according to the level jump number of the first electric signal or the second electric signal, wherein the level jump of the first electric signal or the second electric signal comprises the jump from high level to low level and the jump from low level to high level.

Optionally, the method further comprises:

determining a focusing direction of the lens according to the first parameter configuration of the lens and the current rotating direction of the focusing wheel;

when two photoelectric sensors are mounted on the fixing piece, the current phase difference between the positions of the two photoelectric sensors on the fixing piece accords with a preset phase difference, wherein the current phase difference is calculated according to the tooth period included angle and the included angle between the positions of the two photoelectric sensors on the fixing piece.

The embodiment of the invention provides an imaging device and a lens focusing method, wherein the imaging device comprises: the device comprises a focusing wheel, two photoelectric sensors, at least three gratings, a processor, a motor component and a lens, wherein the gratings are distributed on the inner side wall of the focusing wheel, and tooth gaps with equal width exist between adjacent gratings. A processor that first determines a first electrical signal generated by a first photosensor and determines a second electrical signal generated by a second photosensor; wherein the first electrical signal is generated when the first photoelectric sensor passes through the grating, and the second electrical signal is generated when the second photoelectric sensor passes through the grating; then, determining the current rotation direction of the focusing wheel based on a preset parameter table according to the first electric signal and the second electric signal, wherein the parameter table comprises the corresponding relation between the first electric signal and the second electric signal and the preset rotation direction of the focusing wheel; and finally, determining the current rotation angle of the focusing wheel according to the level jump number of the first electric signal or the second electric signal, wherein the level jump of the first electric signal or the second electric signal comprises the jump from high level to low level and the jump from low level to high level.

Therefore, the imaging device and the lens focusing method provided by the embodiment of the invention can determine the current rotation direction and the current rotation angle of the focusing wheel by utilizing the photoelectric sensor, so that the focusing direction and the focusing distance of the lens can be determined according to the determined current rotation direction and the determined current rotation angle of the focusing wheel, and accurate focusing of the lens is realized. The device for focusing by utilizing the photoelectric sensor has the advantages of simple structure, less parts and low processing difficulty, reduces equipment cost and can meet the requirement of mass production. Of course, it is not necessary for any one product or method of practicing the invention to achieve all of the advantages set forth above at the same time.

Drawings

In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a prior art focusing apparatus for focusing an image using a mechanical gear connection;

FIG. 2 is a flowchart of a lens focusing method according to an embodiment of the present invention;

FIG. 3 is a block diagram of a photosensor according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of electrical signals generated by two photosensors in an embodiment of the invention;

FIG. 5 is a schematic view of a grating and tooth gap according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a position of a photosensor according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a handheld infrared thermal imaging device according to an embodiment of the present invention;

FIG. 8 is yet another schematic diagram of a handheld infrared thermal imaging device according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of a photosensor assembly according to an embodiment of the present invention;

FIG. 10 is another schematic view of a photosensor assembly according to an embodiment of the present invention;

FIG. 11 is a flowchart of step 202 in an embodiment of the present invention;

FIG. 12 is a schematic diagram of electrical signals generated by two photosensors in accordance with an embodiment of the present invention;

FIG. 13 is another schematic diagram of electrical signals generated by two photosensors in an embodiment of the invention;

FIG. 14 is a schematic diagram of electrical signals generated by two photosensors in accordance with an embodiment of the present invention;

FIG. 15 is a schematic diagram of electrical signals generated by two photosensors in accordance with an embodiment of the present invention;

FIG. 16 is a schematic illustration of electrical signals generated by two photosensors in accordance with an embodiment of the present invention;

FIG. 17 is a schematic diagram of electrical signals generated by two photosensors in accordance with an embodiment of the present invention;

fig. 18 is a schematic diagram of an image forming apparatus according to an embodiment of the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The embodiment of the invention provides a lens focusing method which is applied to imaging equipment. Wherein the imaging device comprises: the device comprises a focusing wheel, two photoelectric sensors, at least three gratings, a processor, a motor component and a lens, wherein the gratings are distributed on the inner side wall of the focusing wheel, and tooth gaps with equal width exist between adjacent gratings. Referring to fig. 2, fig. 2 is a flowchart of a lens focusing method according to an embodiment of the present invention, including the following steps:

Step 201, determining a first electrical signal generated by a first photoelectric sensor; a second electrical signal generated by a second photosensor is determined.

Wherein the first electrical signal is generated when the first photosensor passes through the grating and the second electrical signal is generated when the second photosensor passes through the grating.

In this step, the processor of the imaging device determines the electrical signals generated by the two photosensors.

It should be noted that, the electrical signal is only generated when the photoelectric sensor detects that the grating on the focusing wheel blocks the correlation optical axis on the device, as shown in fig. 3, fig. 3 is a structural diagram of the photoelectric sensor according to the embodiment of the present invention, and the correlation optical axis exists between the light emitting point and the light receiving point on the photoelectric sensor.

In one implementation, at least two identical gratings are arranged on the focusing wheel, and adjacent gratings have equal-width tooth gaps.

Thus, when the photoelectric sensor passes through the grating, the lengths of time when the correlation optical axis is shielded are equal, and the lengths of time when the correlation optical axis is not shielded are also equal, so that the durations of the generated electric signals are equal, and the time intervals between the two electric signals are also equal.

For example, as shown in fig. 4, fig. 4 is a schematic diagram of electrical signals generated by two photosensors according to an embodiment of the present invention. In fig. 4, when two photosensors pass through the grating, respectively, the first electrical signal generated by the first photosensor is pulse a, and the second electrical signal generated by the second photosensor is pulse B. Pulse a is in time sequence: low level, high level, low level. If 0 represents low and 1 represents high, pulse a can be expressed as: 0. 1, 0, 1, 0. Correspondingly, the pulse B is sequentially as follows in time sequence: low level, high level, low level, high level, low level. If 0 represents low and 1 represents high, pulse B may be expressed as: 0. 0, 1, 0, 1, 0.

Step 202, determining the current rotation direction of the focusing wheel based on a preset parameter table according to the first electric signal and the second electric signal.

The parameter table comprises a corresponding relation between a first electric signal and a second electric signal and a preset rotation direction of the focusing wheel.

In this step, the processor of the imaging apparatus determines the current rotation direction of the focusing wheel according to the determined electric signals generated by the two photosensors, respectively, and a preset parameter table, to further determine the focusing direction of the lens.

In the imaging device, when the rotation directions of the focusing wheel are different, the sequences of the two photoelectric sensors passing through the grating are different, and of course, the corresponding relations of the two optical signals respectively generated by the two photoelectric sensors are also different, so that the current rotation direction of the focusing wheel can be determined according to the two electric signals respectively generated by the two photoelectric sensors based on the corresponding relations in the parameter table.

And 203, determining the current rotation angle of the focusing wheel according to the level jump number of the first electric signal or the second electric signal.

Wherein the level transition of the first electrical signal or the second electrical signal includes a transition from a high level to a low level and a transition from a low level to a high level.

In this step, the processor of the imaging apparatus determines the rotation angle of the focusing wheel according to the level jump condition of the electric signal generated by one of the two photosensors, to further determine the focusing distance of the lens.

In one implementation, the current rotation angle of the focusing wheel is equal to the number of level jumps multiplied by a tooth period angle, where the tooth period angle is an angle corresponding to a tooth period on an inner sidewall of the focusing wheel, and the tooth period is a sum of a width of one grating and a width of one tooth gap.

Fig. 5 is a schematic diagram of a grating and a tooth space according to an embodiment of the present invention, and fig. 6 is a schematic diagram of a position of a photoelectric sensor according to an embodiment of the present invention, as shown in fig. 5 and 6. In fig. 5, 1 is a focusing wheel, a grating 501 is a block-shaped shadow portion on the focusing wheel 1, a tooth space 502 is a space between adjacent gratings 501, and 503 is one tooth period. In fig. 6, the grating is a circular ring-shaped grating, and θ is the tooth period angle.

Specifically, the number of level jumps of the first electrical signal or the second electrical signal may be calculated according to the number of rising edges or falling edges of the first electrical signal or the second electrical signal. Thus, the more the level jump number of the first electric signal or the second electric signal is, the larger the calculated current rotation angle of the focusing wheel is, and the further the focusing distance of the lens is.

For example, when the number of rising edges of the first electric signal is 10 and the tooth period included angle is 3 degrees, the rotation angle of the focusing wheel can be determined to be 30 degrees. Of course, the rotation angle of the focusing wheel may be determined by comprehensively considering the number of rising edges or falling edges of the electric signals generated by the two photoelectric sensors.

Therefore, the lens focusing method provided by the embodiment of the invention can determine the current rotation direction and the current rotation angle of the focusing wheel by utilizing the photoelectric sensor, so that the focusing direction and the focusing distance of the lens can be determined according to the determined current rotation direction and the determined current rotation angle of the focusing wheel, and the preparation focusing of the lens is realized. The device for focusing by utilizing the photoelectric sensor has the advantages of simple structure, less parts and low processing difficulty, reduces equipment cost and can meet the requirement of mass production.

In an alternative implementation, after step 203 in the lens focusing method shown in fig. 2, the lens focusing method may further include:

The first parameter configuration includes a configuration relation between a rotation direction of the focusing wheel and a focusing direction of the lens, and when the rotation direction of the focusing wheel is clockwise or anticlockwise, the focusing direction of the lens moves along the axial direction.

The second parameter configuration includes a focusing distance by a rotational angle of the focusing wheel and the lens, wherein the focusing distance of the lens is determined by the rotational angle of the focusing wheel and a parameter of a motor component of the lens.

Specifically, after determining the current rotation direction of the focusing wheel, the processor may determine the focusing direction of the lens along the axial direction according to the first parameter configuration of the lens. The first parameter configuration prescribes a configuration relation between the rotation direction of the focusing wheel and the focusing direction of the lens; for example, when the rotation direction of the focusing wheel is clockwise, the focusing direction of the lens is drawn along the axis, and when the rotation direction of the focusing wheel is counterclockwise, the focusing direction of the lens is pushed away along the axis.

Similarly, after determining the current rotation angle of the focusing wheel, the processor may determine the focusing distance of the lens along the axial direction according to the second parameter configuration of the lens. Wherein the second parameter configuration specifies a focusing distance by a rotational angle of the focusing wheel and the lens, wherein the focusing distance is determined by the rotational angle and parameters of the motor component; for example, every 5 degrees of rotation of the focusing wheel is specified, the motor part rotates 1 turn, and the focusing distance of the corresponding lens is 0.1 cm, so that when the rotation angle of the focusing wheel is 10 degrees, the rotation turn of the motor part is 2 turns, and the focusing distance of the corresponding lens is 0.2 cm.

After the processor determines the focusing direction and the focusing distance of the lens, the motor can accurately focus the lens according to the determined focusing distance and the determined focusing direction.

Thus, first, the processor determines the rotational direction and rotational angle of the focusing wheel from the electrical signals generated by the two photosensors, and then, based on the first parameter configuration and the second parameter configuration, determines the focusing direction and focusing distance of the lens from the rotational direction and rotational angle of the focusing wheel, so that the lens can be accurately focused in accordance with the determined focusing direction and focusing distance.

In order to clearly illustrate the lens focusing method provided by the embodiment of the invention, a specific form of the handheld infrared thermal imaging device as an imaging device will be described below by taking a specific form of the infrared lens as a lens as an example. Fig. 7 to 10 show a schematic diagram of a handheld infrared thermal imaging device according to an embodiment of the present invention, fig. 8 shows a further schematic diagram of a handheld infrared thermal imaging device according to an embodiment of the present invention, fig. 9 shows a schematic diagram of a photosensor assembly according to an embodiment of the present invention, and fig. 10 shows another schematic diagram of a photosensor assembly according to an embodiment of the present invention. However, the imaging apparatus in the embodiment of the present invention is not limited to the hand-held infrared thermal imaging apparatus shown in fig. 7 to 10.

As shown in fig. 7 and 8, the hand-held infrared thermal imaging apparatus includes: the focusing device comprises a focusing wheel 1, two photoelectric sensors 2, a fixing piece 3, a motor 4, a main lens barrel 5, a focusing lens barrel 6, a first lens 7, a second lens 8, a pin 9 and a focusing pressing ring 10.

Wherein the focusing barrel 6 is axially movably provided within the main barrel 5. The first lens 7 is fixedly arranged in the main lens barrel 5. The mounting 3 is fixed in the lateral wall that is close to motor 4 direction on the main lens cone 5, and two photoelectric sensor 2 are installed on the mounting 3, and focusing wheel 1 rotatable be fixed in the lateral wall that is kept away from motor 4 direction on the main lens cone 5, there is first clearance along the axial direction of main lens cone 5 between focusing wheel 1 and the mounting 3. The motor 4 is mounted on the outer side wall of the main barrel 5.

As shown in fig. 9, at least two gratings are provided on the inner side wall of the focusing wheel 1, and the gaps between adjacent two gratings are equal. The photoelectric sensor 2 is used for generating an electric signal when sensing that the grating passes through the photoelectric sensor 2 and sending the generated electric signal to the processor. And the processor is electrically connected with the motor 4 and is used for driving the motor 4 to drive the focusing lens barrel 6 to move according to the electric signal sent by the photoelectric sensor 2.

The first lens 7 fixed in the main barrel 5 may be immovable. In this way, the focusing lens barrel 6 can be driven by the motor 4 to axially move in the main lens barrel 5, so as to drive the focusing lens barrel 6 to axially move back and forth along the main lens barrel 5, and focusing is achieved.

The second lens 8 is fixedly disposed in the focusing barrel 6.

Thus, when the focusing lens barrel 6 moves forward and backward along the axial direction of the main lens barrel 5, the second lens positioned in the focusing lens barrel 6 can be driven to move forward and backward along the axial direction of the main lens barrel 5, and focusing is realized by changing the relative position between the second lens 8 and the first lens 7.

The motor 4 is connected with the focusing lens barrel 6 through a pin 9. And the motor 4 is used for driving the focusing lens barrel 6 to axially move through the pin 9 so as to adjust the relative position between the second lens 8 and the first lens 7.

Thus, when the processor drives the motor 4 to operate according to the received electrical signal, the motor 4 can further drive the focusing lens barrel 6 to move along the axial direction of the main lens barrel 5 through the pin 9 so as to adjust the relative position between the second lens 8 and the first lens 7, and focusing is achieved.

Specifically, a first gap between the focusing wheel 1 and the fixing member 3 along the axial direction of the main lens barrel 5 is a preset distance, and when the first gap is the preset distance, the photoelectric sensor passes through the grating when the focusing wheel 1 rotates. The fixing piece 3 is fixedly sleeved on the outer side wall of the main lens barrel 5, which is close to the direction of the motor 4; the focusing wheel 1 is rotatably fixed and sleeved with the outer side wall of the main lens barrel 5 in the direction far away from the motor 4; a second gap exists between the focusing wheel 10 and the outer side wall of the main barrel 5.

For further description of the mounting positions between the focusing press 10, the focusing wheel 1, and the fixing member 3, reference is made to fig. 10. As shown in fig. 10, the focusing press 10 and the fixing member 3 may be connected by a screw structure. The focusing pressing ring 10 is arranged between the focusing wheel 1 and the main lens barrel 5 through the fixing piece 3. The focusing pressing ring 10 is used for fixing the focusing wheel 1 in a clearance manner, so that the focusing wheel 1 can flexibly rotate and cannot fall off from the main lens barrel 5, and the photoelectric sensor 2 can accurately pass through the grating on the focusing wheel 1 when the focusing wheel 1 rotates.

Furthermore, two photosensors 2 are mounted on the mount 3, and the positions of the two photosensors 2 on the mount 3 are adjustable.

As shown in fig. 7, 8 and 10, the handheld infrared thermal imaging apparatus further includes: a PCB section 11; the PCB component includes a PCB board.

The PCB component 11 is fixedly mounted on the fixture 3. Two photosensors 2 are mounted on the PCB board.

Specifically, the PCB part 11 includes a PCB board, the photoelectric sensor 2 sends the generated electrical signal to the PCB board on the PCB part 11, and the PCB board sends the electrical signal to the processor, wherein the PCB board is electrically connected with the processor. Thus, the processor is able to focus the tone Jiao Jingtong based on the electrical signal generated by the photosensor 2.

As shown in fig. 9, the gratings are distributed over the entire circumference of the inner sidewall of the focus wheel 1; alternatively, the gratings may be distributed over part of the circumference of the inner sidewall of the focusing wheel 1.

That is, when the gratings are distributed over the entire circumference of the inner side wall of the focus wheel 1, a plurality of gratings form a circular ring grating. When the gratings are distributed on a part of the circumference of the inner side wall of the focusing wheel 1, a plurality of gratings form an arc grating. In practical application, the grating can be set according to specific requirements.

When the focusing wheel 1 rotates, the two photoelectric sensors 2 sequentially pass through the grating on the focusing wheel 1. When the photoelectric sensor passes through the grating, an optical signal is generated due to the fact that the correlation optical axis is shielded by the grating, then the photoelectric sensor generates an electric signal according to the generated optical signal, and the generated electric signal is sent to the processor; then, the processor determines the current rotation direction of the focusing wheel 1 based on the received two electrical signals.

In one implementation, referring to fig. 11, fig. 11 is a specific flowchart of step 202 in an embodiment of the present invention, and step 202 in the lens focusing method shown in fig. 2 may specifically include the following sub-steps:

step 11, judging whether the tooth ratio of the grating and the phase difference between the positions of the two photoelectric sensors accord with any one of the formulas (1), (2) and (3); if yes, sub-step 12 is performed.

In this step, the processor of the imaging device determines whether the tooth ratio of the grating and the phase difference between the positions of the two photosensors in the currently used imaging device conform to the first electrical signal and the second electrical signal in the preset parameter table, and in the corresponding relation between the preset rotation direction of the focusing wheel, the limiting condition for the tooth ratio of the grating and the phase difference between the positions of the two photosensors on the fixing member, specifically, the limiting condition requires that the tooth ratio of the grating be a preset value and the phase difference between the positions of the two photosensors on the fixing member be a preset phase difference.

That is, the parameter table also includes a preset phase difference between the positions of the two photosensors on the mount. When the two photoelectric sensors are mounted on the fixing piece, the current phase difference between the positions of the two photoelectric sensors on the fixing piece accords with the preset phase difference, the tooth ratio of the grating is also a preset value, and at the moment, the processor can determine the current rotation direction of the focusing wheel based on the reference table according to the first electric signal and the second electric signal.

The current phase difference between the positions of the two photoelectric sensors on the fixing piece can be calculated according to the tooth period included angle and the included angle between the positions of the two photoelectric sensors on the fixing piece.

The limiting conditions are specifically shown as a formula (1), a formula (2) and a formula (3), wherein the formula (1), the formula (2) and the formula (3) comprise preset values of tooth ratios of gratings and preset phase differences between positions of the two photoelectric sensors on the fixing piece. As long as the tooth ratio of the grating and the phase difference between the positions of the two photosensors on the mount satisfy the preset ratio of the tooth ratio defined in any one of the formulas and the preset phase difference between the positions of the two photosensors on the mount, it is explained that the tooth ratio of the grating and the phase difference between the positions of the two photosensors on the mount in the currently used imaging apparatus satisfy the constraint condition.

Wherein d represents a tooth ratio of: a ratio of a width of one grating to one tooth period; ω represents the phase difference between the positions of the two photosensors.

For the calculation method of the current phase difference between the positions of the two photoelectric sensors on the fixing piece, it is also required to explain that:

the processor of the imaging device may calculate the current phase difference between the two photosensors and the position on the mount based on the relative positions of the two photosensors on the mount, i.e., the angle between the positions of the two photosensors on the mount.

As shown in fig. 6, the radius of the radial circle in the grating of the circular ring-shaped grating is R. The two photoelectric sensors 12 and 13 are positioned on the grating pitch diameter circle, the intersection point of the correlation optical axis of the photoelectric sensor 12 and the grating pitch diameter circle is P, and the intersection point of the correlation optical axis of the photoelectric sensor 13 and the grating pitch diameter circle is Q. The phase of point P in its tooth period is ω1 and the phase of point Q in its tooth period is ω2, then the absolute value of the phase difference between point P and point Q is |ω1- ω2|, that is, the current phase difference of photosensors 12 and 13 for the tooth period is ω= |ω1- ω2|. For convenience of explanation, ω is hereinafter referred to as the current phase difference between the positions of the two photosensors on the mount.

The angle between the positions of the two photosensors 12 and 13 on the mount can be denoted as α. Specifically, the calculated relationship between the angle α between the positions of the two photosensors 12 and 13 on the mount and the current phase difference ω between the positions of the two photosensors 12 and 13 on the mount is as shown in formula (4):

in formula (4), ω is the current phase difference between the positions of the two photosensors 12 and 13 on the mount; θ is a tooth period angle; alpha is the angle between the positions of the two photosensors 12 and 13 on the mount; i=1, 2,3.

In this way, the processor can calculate the current phase difference between the positions of the two photosensors 12 and 13 on the fixing member according to the angle between the positions of the two photosensors 12 and 13 on the fixing member, and further determine whether the current phase difference conforms to any one of the formulas (1) to (3) as shown.

And a sub-step 12 of determining the current rotation direction of the focusing wheel based on a preset parameter table according to the first electric signal and the second electric signal.

In this step, when the processor of the imaging apparatus determines that the tooth ratio of the grating in the currently used imaging apparatus and the phase difference between the positions of the two photosensors conform to any one of the formulas (1), (2), and (3), the current rotation direction of the focusing wheel may be determined according to the correspondence between the first and second electric signals in the preset parameter table and the preset rotation direction of the focusing wheel.

In one implementation, the parameter table includes a correspondence between five consecutive level signals of the first electrical signal, five consecutive level signals of the second electrical signal corresponding to the first electrical signal, and a preset rotation direction of the focusing wheel.

That is, the current rotation direction of the focus wheel may be determined based on the parameter table from the first electric signal and five consecutive level signals of the second electric signal corresponding to the first electric signal.

In one implementation, the parameter table specifically includes:

when the first electric signal comprises a low level, a high level, a low level and a low level in time sequence in a first time period, and the corresponding second electric signal comprises the low level, the high level and the low level in the first time period, the corresponding focusing wheel preset rotation direction is clockwise;

when the first electric signal comprises a low level, a high level and a low level in time sequence in the second time period, and the corresponding second electric signal comprises the low level, the high level, the low level and the low level in the second time period, the corresponding focusing wheel preset rotation direction is a counterclockwise direction.

That is, when the focusing wheel rotates, the first photoelectric sensor generates a first electric signal, and the second photoelectric sensor generates a second electric signal.

The following describes the correspondence relationship in the parameter table in detail with reference to the formulas (1) to (3):

first case: the tooth ratio of the grating and the phase difference between the positions of the two photosensors in the currently used imaging apparatus conform to the formula (1), and when the first electrical signal includes a low level, a high level, a low level in time sequence for a period of time, and the corresponding second electrical signal includes a low level, a high level, a low level for the period of time, the rotation direction of the corresponding focusing wheel is clockwise.

With 0 representing low level and 1 representing high level, then when the electric signals generated by the first and second photosensors are as shown in fig. 12, it can be determined that the rotational direction of the corresponding focusing wheel is clockwise. Fig. 12 is a schematic diagram of an electrical signal generated by two photosensors in accordance with an embodiment of the present invention. As shown in fig. 12, pulse E generates a first electrical signal for the first photosensor and pulse F generates a second electrical signal for the second photosensor. As can be seen from fig. 12, when the level of the first electrical signal is 0, the level of the corresponding second electrical signal is 0; when the level of the first electric signal jumps from 0 to 1, the level of the corresponding second electric signal is 0; when the level of the first electric signal is 1, the level of the corresponding second electric signal jumps from 0 to 1; when the level of the first electric signal jumps from 1 to 0, the level of the corresponding second electric signal is 1; the level of the corresponding second electrical signal jumps from 1 to 0 when the first electrical signal is 0.

Second case: the tooth ratio of the grating and the phase difference between the positions of the two photosensors in the currently used imaging apparatus conform to the formula (2), and when the first electrical signal includes a low level, a high level, a low level in time sequence for a period of time, and the corresponding second electrical signal includes a low level, a high level, a low level for the period of time, the rotation direction of the corresponding focusing wheel is clockwise.

When the level jump condition of the electric signals generated by the first and second photosensors is as shown in fig. 13, it can be determined that the rotation direction of the corresponding focus wheel is clockwise. Fig. 13 is another schematic diagram of the electrical signals generated by two photosensors in an embodiment of the invention. As can be seen from fig. 13, the electrical signal shown in fig. 13 is identical to the level transition law of the electrical signal shown in fig. 12, except that the interval duration of the level transitions of the electrical signal is different.

Third case: the tooth ratio of the grating and the phase difference between the positions of the two photosensors in the currently used imaging apparatus conform to the formula (3), and when the first electrical signal includes a low level, a high level, a low level in time sequence for a period of time, and the corresponding second electrical signal includes a low level, a high level, a low level for the period of time, the rotational direction of the corresponding focusing wheel is clockwise.

When the level jump condition of the electrical signals generated by the first photoelectric sensor and the second photoelectric sensor is shown in fig. 14, the rotation direction of the corresponding focusing wheel can be determined to be clockwise, and fig. 14 is a further schematic diagram of the electrical signals generated by the two photoelectric sensors in the embodiment of the present invention.

As can be seen from fig. 14, the jump condition of the electric signal shown in fig. 14 is the same as the level jump rule of the electric signal shown in fig. 12 and 13, except that the interval duration of the level jumps of the electric signal is different.

Fourth case: the tooth ratio of the grating and the phase difference between the positions of the two photosensors in the imaging apparatus currently used satisfy the formula (1), and when the first electric signal includes a low level, a high level, a low level in time sequence for a period of time, and the corresponding second electric signal includes a low level, a high level, a low level for the period of time, the rotation direction of the corresponding focusing wheel is counterclockwise.

When the level jump condition of the electrical signals generated by the first photoelectric sensor and the second photoelectric sensor is shown in fig. 15, the rotation direction of the corresponding focusing wheel can be determined to be counterclockwise, and fig. 15 is a schematic diagram of the electrical signals generated by the two photoelectric sensors in the embodiment of the present invention.

As can be seen from fig. 15, the level of the first electrical signal is 0, and the level of the corresponding second electrical signal is 0; when the level of the first electric signal is 0, the level corresponding to the second electric signal jumps from 0 to 1; the level of the first electric signal is 1 when the level of the first electric signal jumps from 0 to 1; when the level of the first electric signal is 1, the level corresponding to the second electric signal jumps from 1 to 0; the level of the first electrical signal transitions from 1 to 0 and the corresponding level of the second electrical signal is 0.

Fifth case: the tooth ratio of the grating and the phase difference between the positions of the two photosensors in the imaging apparatus currently used satisfy the formula (2), and when the first electric signal includes a low level, a high level, a low level in time sequence for a period of time, and the corresponding second electric signal includes a low level, a high level, a low level for the period of time, the rotation direction of the corresponding focusing wheel is counterclockwise.

When the level jump condition of the electrical signals generated by the first photoelectric sensor and the second photoelectric sensor is shown in fig. 16, the rotation direction of the corresponding focusing wheel can be determined to be counterclockwise, and fig. 16 is a further schematic diagram of the electrical signals generated by the two photoelectric sensors in the embodiment of the present invention.

As can be seen from fig. 16, the hopping situation of the electrical signal shown in fig. 16 is the same as the level hopping rule of the electrical signal shown in fig. 15, except that the interval duration of the level hopping of the electrical signal is different.

Sixth case: the tooth ratio of the grating and the phase difference between the positions of the two photosensors in the currently used imaging apparatus conform to the formula (3), and when the first electrical signal includes a low level, a high level, a low level in time sequence for a period of time, and the corresponding second electrical signal includes a low level, a high level, a low level for the period of time, the rotational direction of the corresponding focusing wheel is counterclockwise.

When the level jump condition of the electric signals generated by the first photoelectric sensor and the second photoelectric sensor is shown in fig. 17, the rotation direction of the corresponding focusing wheel can be determined to be counterclockwise, and fig. 17 is a further schematic diagram of the electric signals generated by the two photoelectric sensors in the embodiment of the present invention.

As can be seen from fig. 17, the jump condition of the electric signal shown in fig. 17 is the same as the level jump rule of the electric signal shown in fig. 15 and 16, except that the interval duration of the level jumps of the electric signal is different.

In summary, according to the level jump cases shown in fig. 12 to 17, it can be determined that on the premise that the tooth ratio of the grating and the phase difference between the positions of the two photosensors in the currently used imaging apparatus conform to any one of the formulas (1) to (3), the correspondence relationship between the electric signals generated by the first photosensor and the second photosensor and the preset rotation direction of the focusing wheel can be shown in table 1.

TABLE 1

In table 1, among each pair of electrical signals, the former is a first electrical signal generated by a first photosensor and the latter is a second electrical signal generated by a second photosensor; for example, for electrical signal 10, 1 is the first electrical signal and 0 is the second electrical signal.

In practical applications, in order to facilitate the processor to process the level jump situation of the electrical signal, the electrical signal expressed in the form of 0 and 1 may be converted into a decimal number, for example, the converted signal corresponding to the electrical signal 10 is the decimal number 2. Thus, when the processor receives the converted signal sent by the PCB and is 0-2-3-1-0, the rotation direction of the focusing wheel can be determined to be clockwise; when the processor receives the converted signal sent by the PCB and is 0-1-3-2-0, the rotation direction of the focusing wheel can be determined to be anticlockwise.

It should be noted that, if the tooth ratio of the grating and the phase difference between the positions of the two photosensors in the currently used imaging apparatus do not conform to formulas (1) to (3), the lens focusing method described in the embodiment of the present invention cannot be used.

It can be seen that in the embodiment of the invention, according to the tooth ratio of the grating and the phase difference between the positions of the two photoelectric sensors in the imaging device which is actually used, the corresponding relation between the electric signals generated by the first photoelectric sensor and the electric signals generated by the second photoelectric sensor and the preset rotation direction of the focusing wheel can be determined, so that the current rotation direction of the focusing wheel is determined according to the electric signals generated by the first photoelectric sensor and the second photoelectric sensor, and further accurate focusing is realized.

The embodiment of the invention also provides an imaging device, referring to fig. 18, fig. 18 is a schematic diagram of the imaging device according to the embodiment of the invention, as shown in fig. 18, the imaging device includes: a focusing wheel 1801, two photosensors 1802, at least three gratings 1803, a processor 1804, a motor assembly 1805, and a lens 1806, wherein the gratings 1803 are distributed on an inner sidewall of the focusing wheel 1801.

A processor 1804 for determining a first electrical signal generated by the first photosensor;

a processor 1804 for determining a second electrical signal generated by a second photosensor; wherein the first electrical signal is generated when the first photoelectric sensor passes through the grating, and the second electrical signal is generated when the second photoelectric sensor passes through the grating;

a processor 1804, configured to determine a current rotation direction of the focusing wheel 1801 based on a preset parameter table according to the first electrical signal and the second electrical signal, where the parameter table includes a correspondence between the first electrical signal and the second electrical signal and the preset rotation direction of the focusing wheel 1801;

the processor 1804 is configured to determine, according to the number of level transitions of the first electrical signal or the second electrical signal, a current rotation angle of the focusing wheel 1801, where the level transitions of the first electrical signal or the second electrical signal include a transition from a high level to a low level and a transition from a low level to a high level.

Optionally, the processor 1804 is further configured to determine a focusing direction of the lens 1806 according to the first parameter configuration of the lens 1806 and the current rotation direction of the focusing wheel 1801;

determining a focusing distance of the lens 1806 according to the second parameter configuration of the lens 1806 and the current rotation angle of the focusing wheel 1801;

the motor section focuses the lens 1806 based on the focusing direction of the lens 1806 and the focusing distance of the lens 1806.

Optionally, the current rotation angle of the focusing wheel 1801 is equal to the number of level jumps multiplied by a tooth period angle, where the tooth period angle is an angle corresponding to a tooth period on the inner sidewall of the focusing wheel 1801, and the tooth period is a sum of a width of one grating 1803 and a width of one tooth gap.

Optionally, the imaging device further comprises a fixing member, and the two photoelectric sensors 1802 are mounted on the fixing member;

the parameter table also includes a preset phase difference between the positions of the two photosensors 1802 on the mount;

when two photosensors 1802 are mounted on the mount, the current phase difference between the positions of the two photosensors 1802 on the mount corresponds to a preset phase difference, wherein the current phase difference is calculated from the tooth cycle angle and the angle between the positions of the two photosensors 1802 on the mount.

Optionally, the parameter table includes a correspondence between five continuous level signals of the first electrical signal, five continuous level signals of the second electrical signal corresponding to the first electrical signal, and a preset rotation direction of the focusing wheel 1801.

Optionally, the parameter table includes: when the first electrical signal includes a low level, a high level, a low level, and a low level in time sequence in the first period, and the corresponding second electrical signal includes a low level, a high level, and a low level in the first period, the corresponding focusing wheel 1801 is rotated clockwise;

when the first electrical signal includes a low level, a high level, and a low level in time sequence in the second period, and the corresponding second electrical signal includes a low level, a high level, a low level, and a low level in the second period, the corresponding focusing wheel 1801 is set to have a counterclockwise rotation direction;

the first photoelectric sensor passes through the grating 1803 when the focusing wheel 1801 rotates, and the second photoelectric sensor passes through the grating 1803 after the focusing wheel 1801 rotates.

Optionally, the first parameter configuration includes a configuration relationship between a rotation direction of the focusing wheel 1801 and a focusing direction of the lens 1806, and when the rotation direction of the focusing wheel 1801 is clockwise or counterclockwise, the focusing direction of the lens is moved along the axial direction.

Optionally, the second parameter configuration includes a focusing distance of the lens 1806 and a rotation angle of the focusing wheel 1801, wherein the focusing distance of the lens 1806 is determined by the rotation angle of the focusing wheel 1801 and parameters of the motor component 1805 of the lens.

The processor may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU), a network processor (Network Processor, NP), etc.; but also digital signal processors (Digital Signal Processing, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), field programmable gate arrays (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

Therefore, the imaging equipment provided by the embodiment of the invention can be used for focusing by using the photoelectric sensor, and the device for focusing by using the photoelectric sensor has the advantages of simple structure, less parts, low processing difficulty, equipment cost reduction and capability of meeting the requirement of mass production.

It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

In this specification, each embodiment is described in a related manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment mainly describes differences from other embodiments. In particular, for the imaging device embodiments, since they are substantially similar to the method embodiments, the description is relatively simple, and reference is made to the description of the method embodiments in part.

The foregoing description is only of the preferred embodiments of the present invention and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. An image forming apparatus, characterized in that the image forming apparatus comprises: the device comprises a focusing wheel, two photoelectric sensors, at least three gratings, a processor, a motor component and a lens, wherein the gratings are distributed on the inner side wall of the focusing wheel, and tooth gaps with equal width exist between adjacent gratings;

the processor is used for determining a first electric signal generated by the first photoelectric sensor;

the processor is used for determining a second electric signal generated by a second photoelectric sensor; wherein the first electrical signal is generated when the first photosensor passes through the grating and the second electrical signal is generated when the second photosensor passes through the grating;

The processor is used for determining the current rotation direction of the focusing wheel based on a preset parameter table according to the first electric signal and the second electric signal, wherein the parameter table comprises the corresponding relation between the first electric signal, the second electric signal and the preset rotation direction of the focusing wheel;

the processor is used for determining the current rotation angle of the focusing wheel according to the level jump number of the first electric signal or the second electric signal, wherein the level jump of the first electric signal or the second electric signal comprises the jump from high level to low level and the jump from low level to high level;

the motor component focuses the lens based on the current rotation direction of the focusing wheel and the current rotation angle of the focusing wheel;

the imaging device further comprises a fixing piece, and the two photoelectric sensors are mounted on the fixing piece; the phase difference between the positions of the two photoelectric sensors on the fixing piece meets the limiting condition;

the limiting conditions are as follows: the phase difference between the positions of the two photoelectric sensors on the fixing piece accords with a preset phase difference between the positions of the two photoelectric sensors on the fixing piece, which is defined in any one of the following formulas;

The formula includes:

wherein d represents the tooth ratio of the grating, ω represents a preset phase difference between the positions of the two photosensors on the mount; the tooth ratio of the grating is as follows: a ratio of a width of one grating to one tooth period; the tooth period is the sum of the width of one of the gratings and the width of one of the tooth gaps.

2. The imaging apparatus of claim 1, wherein the image forming apparatus further comprises a controller,

the processor is further used for determining the focusing direction of the lens according to the first parameter configuration of the lens and the current rotating direction of the focusing wheel;

determining a focusing distance of the lens according to the second parameter configuration of the lens and the current rotation angle of the focusing wheel;

the motor part focuses the lens based on a focusing direction of the lens and a focusing distance of the lens.

3. The imaging apparatus of claim 1, wherein the image forming apparatus further comprises a controller,

the current rotation angle of the focusing wheel is equal to the level jump number multiplied by a tooth period included angle, wherein the tooth period included angle is an included angle corresponding to the tooth period on the inner side wall of the focusing wheel.

4. The imaging apparatus of claim 1, wherein the image forming apparatus further comprises a controller,

when the two photoelectric sensors are mounted on the fixing piece, the current phase difference between the positions of the two photoelectric sensors on the fixing piece accords with the preset phase difference, wherein the current phase difference is calculated according to the tooth period included angle and the included angle between the positions of the two photoelectric sensors on the fixing piece.

5. The imaging apparatus of claim 1, wherein the image forming apparatus further comprises a controller,

the parameter table comprises the correspondence between five continuous level signals of the first electric signal, five continuous level signals of the second electric signal corresponding to the first electric signal and the preset rotation direction of the focusing wheel.

6. The imaging apparatus of claim 5, wherein the image forming apparatus further comprises a controller,

the parameter table includes: when the first electric signal comprises a low level, a high level, a low level and a low level in time sequence in a first time period, and the second electric signal corresponding to the first time period comprises the low level, the high level and the low level, the preset rotating direction of the corresponding focusing wheel is clockwise;

When the first electric signal comprises a low level, a high level and a low level in time sequence in a second time period, and the second electric signal corresponding to the second time period comprises the low level, the high level, the low level and the low level, the preset rotating direction of the corresponding focusing wheel is anticlockwise;

7. The imaging apparatus of claim 2, wherein,

the first parameter configuration includes a configuration relation between a rotation direction of the focusing wheel and a focusing direction of the lens, and when the rotation direction of the focusing wheel is clockwise or anticlockwise, the focusing direction of the lens moves along an axial direction.

8. The imaging apparatus of claim 2, wherein,

9. A lens focusing method, characterized by being applied to an imaging apparatus, wherein the imaging apparatus comprises: the device comprises a focusing wheel, two photoelectric sensors, at least three gratings, a processor, a motor component and a lens, wherein the gratings are distributed on the inner side wall of the focusing wheel, and tooth gaps with equal widths exist between adjacent gratings, and the method comprises the following steps:

determining a first electrical signal generated by a first photosensor;

determining a second electrical signal generated by a second photosensor;

wherein the first electrical signal is generated when the first photosensor passes through the grating and the second electrical signal is generated when the second photosensor passes through the grating;

determining the current rotation angle of the focusing wheel according to the level jump number of the first electric signal or the second electric signal, wherein the level jump of the first electric signal or the second electric signal comprises the jump from high level to low level and the jump from low level to high level;

the formula includes:

10. The method according to claim 9, wherein the method further comprises:

11. The method of claim 9, wherein the step of determining the position of the substrate comprises,

12. The method of claim 9, wherein the step of determining the position of the substrate comprises,

13. The method of claim 9, wherein the step of determining the position of the substrate comprises,

14. The method of claim 13, wherein the step of determining the position of the probe is performed,

15. The method of claim 10, wherein the step of determining the position of the first electrode is performed,

16. The method of claim 10, wherein the step of determining the position of the first electrode is performed,