CN117336604A

CN117336604A - Focusing method for non-AA module

Info

Publication number: CN117336604A
Application number: CN202311054611.XA
Authority: CN
Inventors: 庄茂彬
Original assignee: Truly Opto Electronics Ltd
Current assignee: Truly Opto Electronics Ltd
Priority date: 2023-08-22
Filing date: 2023-08-22
Publication date: 2024-01-02

Abstract

The invention relates to a non-AA module focusing method, which comprises the steps of detecting field curvature shrinkage of carried glue, and setting the shrinkage as A; detecting the field curvature variation of the lens, wherein the variation is set as B; manually focusing the image pickup module, and determining whether the image pickup module reaches a preset peak value by reading the analysis paper value, wherein the peak value is set by the lens position of the image pickup module and the analysis paper value, and is set as C; because the peak value is changed due to shrinkage of the glue and the change of the lens field curvature, the C value needs to be compensated, the compensated value is D=C+A+B, and manual focusing is carried out on the camera module under the D value after compensation, so that the analysis force value of the camera module is optimal; and (5) retesting peak values of the camera modules after focusing is completed, and focusing in batches. The invention applies the peak point control scheme, namely, the optimal analytic force position of the imaging of the control module, so that the imaging depth of field of the camera module reaches a preset value, and the optimal effect is met.

Description

Focusing method for non-AA module

Technical Field

The invention relates to the technical field of camera modules, in particular to a non-AA module focusing method.

Background

The peak value of the camera module is that the module resolving power can reach an optimal parameter under the specified focusing distance, but the peak value does not reach the actual requirement due to the fact that the camera module is often changed due to the reasons of manufacturing procedures, materials, lens field curves and the like, so that poor application experience is brought to the application of the module and even the whole equipment.

Disclosure of Invention

The invention provides a correction method of a non-AA module peak value, which can partially solve the technical problems in the prior art.

Specifically, the invention provides a non-AA module focusing method, which comprises the following steps:

detecting field bending shrinkage of the carried glue, wherein the shrinkage is set as A;

detecting the field curvature variation of the lens, wherein the variation is set as B;

manually focusing the image pickup module, and determining whether the image pickup module reaches a preset peak value by reading the analysis paper value, wherein the peak value is set by the lens position of the image pickup module and the analysis paper value, and is set as C; because the peak value is changed due to shrinkage of the glue and the change of the lens field curvature, the C value needs to be compensated, the compensated value is D=C+A+B, and manual focusing is carried out on the camera module under the D value after compensation, so that the analysis force value of the camera module is optimal;

and (5) retesting peak values of the camera modules after focusing is completed, and focusing in batches.

As an optimal technical scheme, the value of C is the distance from the top of the mirror surface of the camera module lens to the surface of the analysis paper by a laser range finder.

As an optimal technical scheme, the AA module after focusing is finished performs peak value sampling retest, namely the AA module performs live-action shooting in a laboratory and performs analysis force test; the method specifically comprises the following steps:

the AA module performs an analytical force test under the peak value distance, reads the analytical force value and sets the analytical force value as TVL1;

the AA module performs an analytical force test at a distance greater than or less than the peak value, reads the analytical force value and sets the analytical force value as TVL2;

comparing TVL1 with TVL2, and judging whether the AA module peak value reaches the best.

As the preferable technical scheme, the AA module carries out analytical force test, and specifically comprises the following steps:

the AA module shoots an I SO12233 analytical force test drawing, and the shot picture is input into the display device; the pictures are output in a proportion of 100% through a display device;

and reading the analysis force values of the center position and the surrounding positions of the drawing.

As a preferable technical scheme, whether the AA module peak value reaches the best is judged, specifically: when the difference between TVL1 and TVL2 is calculated to be 100TV Line or less, the calculation is judged to be optimal.

As the preferable technical scheme, the analysis force values of the center position and the peripheral position of the drawing are read, and the analysis force values are read by an image processing algorithm.

As a preferable technical scheme, the method for detecting the curvature of field variation of the lens specifically comprises the following steps:

by HR equipment, the lens curvature of field position of the test lens at normal temperature is set as B1i, and the lens curvature of field position after high temperature is detected as B2i, where i=1, 2, 3 … … n, and the variation b=b1i—b2i.

As a preferred embodiment, the variables b= [ (B11-B21) + (B12-B22) + (B13-B23) + … … (B1 i-B2 i) ]/i, where i=4, 5, 6 … … n.

As an preferable technical scheme, detecting shrinkage of the carried glue specifically includes:

the thickness value of the carried glue at normal temperature is detected and set as A1i, and the thickness value after high temperature is detected and set as A2i, wherein i=1, 2 and 3 … … n, and the shrinkage A=A1i-A2 i.

As a preferred embodiment, the shrinkage A= [ (A11-A21) + (A12-A22) + (A13-A23) + … … (A1 i-A2 i) ]/i, wherein i=4, 5, 6 … … n.

Compared with the prior art, the invention has the following technical effects: the traditional focusing mode of the camera module takes the best value of the analytic force measured by focusing as the reference, and does not compensate errors generated by field curvature change of the camera module due to relative position change of a lens after glue and lens baking, and although the camera module can achieve a clearer effect in the application distance use of a customer, the clearer effect cannot be achieved.

The invention applies the peak point control scheme, namely the optimal resolution force position of the imaging of the control module, and the peak point of the control module is used for adjusting and compensating the glue variation and the lens field curvature error, so that the imaging depth of field of the camera module reaches a preset value, and the optimal effect in application is met.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Description of the drawings:

FIG. 1 is a flow chart of a non-AA module focusing method according to an embodiment of the present invention;

fig. 2 is a schematic flow chart of performing peak value sampling retest on an AA module after focusing is completed according to an embodiment of the present invention;

FIG. 3 is a flowchart of a method for detecting a lens curvature of field variation according to an embodiment of the present invention;

FIG. 4 is a diagram illustrating the resolution of an AA module according to an embodiment of the present invention;

FIG. 5 is a diagram illustrating a second analysis force value of an AA module according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to specific embodiments of the present invention and corresponding drawings. In the description of the present invention, it should be noted that the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

It should be understood that the various steps recited in the method embodiments of the present application may be performed in a different order and/or performed in parallel. Furthermore, method embodiments may include additional steps and/or omit performing the illustrated steps. The scope of the present application is not limited in this respect.

The term "including" and variations thereof as used herein are intended to be open-ended, i.e., including, but not limited to. The term "based on" is based at least in part on. The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments. Related definitions of other terms will be given in the description below.

It should be noted that references to "one" or "a plurality" in this application are intended to be illustrative rather than limiting, and those of ordinary skill in the art will appreciate that "one or more" is intended to be interpreted as "one or more" unless the context clearly indicates otherwise. "plurality" is understood to mean two or more.

Examples

As shown in fig. 1, a flow chart of a non-AA module focusing method according to an embodiment of the present invention is shown, and specifically, the method includes:

s10: and detecting the field bending shrinkage of the carried glue, and setting the shrinkage as A.

In this example, the thickness of the amount of the carried glue was measured by a metallographic microscope. The average value of the shrinkage is taken as the shrinkage A through multiple experiments. Specifically, the thickness value of the mounting glue at normal temperature is set to A1i, and the thickness value after high temperature is set to A2i, where i=1, 2, 3 … … n, i.e., the shrinkage a=a1i-a2i.

Further, in order to make the value of a more accurate, the present embodiment proposes a method of calculating the value of the shrinkage a. Namely: shrinkage a= [ (a 11-a 21) + (a 12-a 22) + (a 13-a 23) + (A1 i-A2 i) ]/i, wherein i=4, 5, 6 … … n. And (3) through multiple times of verification, obtaining the thickness difference between the glue thickness at normal temperature and the glue thickness after thermal expansion, and obtaining an average value, namely the shrinkage value.

Further, in this embodiment, the temperature range of normal temperature is set to 20-25 ℃, and the temperature range of high temperature is set to 80-90 ℃, so that the glue deformation of the AA camera module is tested at the temperature, which is more accurate.

As shown in table 1 below, this example was tested 10 times to determine the amount of glue deformation:

table 1: measuring the deformation value of the glue

1

2

3

4

5

6

7

8

9

10

A1i

309um

310um

305um

312um

305um

309um

310um

309um

303um

301um

A2i

299um

320um

314um

303um

315um

320um

322um

320um

315um

310um

Calculating the shrinkage through a calculation method formula: a= (a 11-a 21) + (a 12-a 22) + (a 13-a 23) + (A1 i-A2 i)/i, where in this example i=10, is calculated to:

A＝[(309-299)+(320-310)+(314-305)+(312-303)+(315-305)+(320-309)+(322-310)+(320-309)+(315-303)+(310-301)]/10＝10.3um。

s20: and detecting the field curvature variation of the lens, wherein the variation is set as B.

Specifically, by HR devices (trioticsThe HR series test equipment is equipment developed by the company of triotics and used for testing the optical performance of the lens, has a plurality of functions, can realize accurate optical test, and comprises a plurality of different models and adaptation modules so as to meet the requirements of customers on testing different application lenses, such as lenses with different sizes, different angles of view, different application wave bands, limited distance/infinite distance and the like). As shown in fig. 3, the method comprises the following steps:

s201: the lens curvature of field at normal temperature was measured and set to B1i.

S202: and detecting the lens curvature of field after the high temperature, and setting the lens curvature of field as B2i, wherein i=1, 2 and 3 … … n, and the variation B=B1i-B2 i.

It is further preferred that in order to obtain a more accurate change in the curvature of field of the lens, the average of the change amounts is taken, i.e. b= [ (B11-B21) + (B12-B22) + (B13-B23) + (… … (B1 i-B2 i) ]/i, where i=4, 5, 6 … … n.

As shown in table 2 below, 10 tests were performed to measure the field curvature change amount in this example:

table 2: measuring the field curvature change value

	1	2	3	4	5	6	7	8	9	10
											B1i	0	0	0	0	0	0	0	0	0	0
B2i	5um	5um	4um	3um	4um	4um	5um	4um	3um	5um

In general, the default field curvature position of B1i at normal temperature is 0, and B2i is the field curvature position shifted after high temperature. In this example, after 10 tests, it was calculated that:

the field curvature variation is b= (5um+5um+4um+3um+4um+4um+5um+4um+3um+5um)/10=4.2 um.

S30: manually focusing the image pickup module, and determining whether the image pickup module reaches a preset peak value by reading the analysis paper value, wherein the peak value is set by the lens position of the image pickup module and the analysis paper value, and is set as C; because the glue shrinkage and the lens field curvature change cause the peak value to change, the C value needs to be compensated, the compensated value is D=C+A+B, and the camera module is manually focused under the compensated value D value, so that the analysis force value of the camera module is optimal.

Preferably, the value of C is the distance from the top of the mirror surface of the camera module lens to the surface of the analysis paper measured by a laser range finder. Because of different camera modules, the peak value is also different, resulting in a different value of C. Since there is an error in measurement, the value of C is also measured multiple times, and then the average value thereof, that is, the calculation formula of the value of C may be c= (c1+c2+c3+ … … Ci)/i, where i=4, 5, 6 … … n.

As shown in table 3 below, this example was tested 10 times to determine the C value:

table 3: measurement of the value of C

The calculation results are that: c= (200.00mm+200.05mm+200.03mm+199.97mm+199.96mm+

200.01mm+200.00mm+200.00mm+200.00mm+200.00mm)/10＝200mm

In the manual focusing process, D is a compensated value, where C, A, B is a value obtained by taking an average value of the compensated values after multiple measurements, i.e., d=200 mm+10.3um+4.2um in this embodiment.

S40: and (3) retesting the peak value of the camera module after focusing is finished, determining whether the compensation operation is feasible, and focusing in batches according to the method and leaving a factory if the retesting is good.

Preferably, the AA module after focusing is completed performs peak value sampling retest, that is, real shot in the AA module laboratory, and performs resolution test, as shown in fig. 2, and specifically includes:

s401: the AA module performs an analytical force test under the peak value distance, reads the analytical force value and sets the analytical force value as TVL1;

s402: the AA module performs an analytical force test at a distance greater than or less than the peak value, reads the analytical force value and sets the analytical force value as TVL2;

s403: comparing TVL1 with TVL2, and judging whether the AA module peak value reaches the best.

Further, the AA module performs an analytical force test, specifically including: the AA module shoots an ISO12233 analytical force test drawing, and the shot picture is input into the display device; the pictures are output in a proportion of 100% through a display device; and reading the analysis force values of the center position and the surrounding positions of the drawing, as shown in fig. 4 and 5.

Preferably, in this embodiment, the analysis force values of the center position and the peripheral position of the drawing are read, and the analysis force values are read by an image processing algorithm. The image processing algorithm is to scan Line by Line along the direction of the TV Line, analyze the gray curve of each Line, respectively calculate the first derivative and the second derivative, and determine the boundary of the lines according to the derivative change, namely, the number of the lines at the moment is counted; scanning, analyzing and processing the 'digit line' in turn until the 'digit line' cannot be counted. The use of the fountain map for measurement is more visual, but has a slightly higher requirement on the environment as to whether the image area is full of the test card.

In other embodiments, the reading may be performed manually, and if the analysis force values at the center and the periphery of the test drawing are read by naked eyes, the analysis force value is the value that can be maximally seen and is not overlapped with the separation between the lines.

Preferably, whether the AA module peak value reaches the best is determined by: when the difference between TVL1 and TVL2 is calculated to be 100TV Line or less, the calculation is judged to be optimal.

As shown in the following table 4, the present embodiment is verified by 10 tests, and the center value of the drawing is read:

the values in the table show that the difference value of 7 groups of values in 10 groups of comparison values is less than or equal to 100TVL.

As shown in the following table 5, the present embodiment is verified by 10 tests, and the four-week numerical value of the drawing is read:

the values in the table show that the difference value of 8 groups of values in 10 groups of comparison values is less than or equal to 100TVL. By combining the two groups of data, the method plays a good role in the peak value correction of the non-AA module, and then the best resolving power of the camera module can be realized by adopting the focusing method. The batch modules can be focused according to the method and leave the factory.

It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. 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.

Claims

1. The non-AA module focusing method is characterized by comprising the following steps of:

detecting field bending shrinkage of carried glue, wherein the shrinkage is set as A;

manually focusing the camera module, and determining whether the camera module reaches a preset peak value or not by reading the analysis force drawing value, wherein the peak value is set by the distance between the lens position of the camera module and the analysis force drawing paper and is set as C; because the peak value is changed due to shrinkage of the glue and change of the lens field curvature, the C value needs to be compensated, the compensated value is D=C+A+B, and manual focusing is carried out on the camera module under the D value after compensation, so that the analysis force value of the camera module is optimal;

and re-measuring peak values of the camera modules after focusing is completed, and focusing in batches.

2. The method of claim 1, wherein the value of C is a distance from a top of a mirror of the camera lens to a surface of the resolution map.

3. The non-AA module focusing method according to claim 1, wherein the AA module after focusing is completed performs peak value sampling retest, that is, the AA module performs live-action shooting, and performs resolution test; the method specifically comprises the following steps:

the AA module performs analysis force test under the peak value distance, reads the analysis force value and sets the analysis force value as TVL1;

comparing the TVL1 with the TVL2, and judging whether the AA module peak value reaches the best.

4. The non-AA module focusing method according to claim 3, wherein the AA module performs an analytical force test, specifically comprising:

the AA module shoots an ISO12233 analytic force test drawing and inputs the shot picture into the display device;

the pictures are output in a proportion of 100% through the display device;

and reading the analysis force values of the center position and the peripheral position of the drawing.

5. The method for focusing on a non-AA module of claim 4, wherein the determining whether the AA module peak value is optimal is specifically: and when the difference value between the TVL1 and the TVL2 is calculated to be less than or equal to 100TV Line, judging the difference value to be the best.

6. The non-AA module focusing method of claim 4, wherein the reading of the resolution values of the center and periphery positions of the drawing is performed by an image processing algorithm.

7. The non-AA module focusing method according to claim 1, wherein the detecting the lens curvature of field variation comprises:

by HR equipment, the lens curvature of field position of the test lens at normal temperature is set as B1i, and the lens curvature of field position after high temperature is detected as B2i, wherein i=1, 2, 3 … … n, and the variation b=b1i-B2 i.

8. The method of claim 7, wherein the variation b= [ (B11-B21) + (B12-B22) + (B13-B23) + (… … (B1 i-B2 i) ]/i, wherein i=4, 5, 6 … … n.

9. The non-AA module focusing method according to claim 1, wherein the detecting the shrinkage of the carrier glue comprises:

the thickness value of the carrying glue at normal temperature is detected and set as A1i, and the thickness value after high temperature is detected and set as A2i, wherein i=1, 2 and 3 … … n, and the shrinkage A=A1i-A2 i.

10. The non-AA module focusing method of claim 9, wherein the shrinkage a= [ (a 11-a 21) + (a 12-a 22) + (a 13-a 23) + … … (A1 i-A2 i) ]/i, wherein i = 4, 5, 6 … … n.