TW201321734A - Optometric automatic inspection apparatus and method - Google Patents

Abstract

The invention discloses an optometric automatic inspection apparatus and method for inspecting diopter, astigmia and sharpness of spectacle lens. An image analysis method is used to carry out image acquisition and interpretation. Automated focusing is operated by an automatic control technique instead of manual operation so that inspection for diopter, astigmia and sharpness of spectacle lens can be automated. Error of manual operation can be reduced substantially while inspection effectiveness can be raised.

Description

Optometry automatic detecting device and method

The invention relates to an automatic optical inspection device and method, in particular to an automatic optical inspection of diopter, astigmatism and sharpness of an eyeglass lens.

In recent years, the demand for glasses for Chinese people has changed from functional orientation to personal accessories, so the demand for various types of glasses has increased significantly. But the market is full of all kinds of glasses, from vision correction glasses, safety glasses to sunglasses, the quality is very different, so there are several test items for glasses: diopter, astigmatism, diffused light, twist, Surrounding vision, Pauli test, etc. In the various testing items of glasses, the two characteristics of diopter and astigmatism affect the clarity of the wearer to view the scene, which is a very important lens quality testing item. All kinds of safety glasses are listed as necessary testing items. In the international standard ANSI/ISEA Z87.1-2010, the system architecture of the diopter and astigmatism optometry instrument is shown in Figure 1. The detection system contains the eyepiece B and manual focus mechanism C required for the inspection of the eye A of the tester. , telescope D, lens E to be tested, and test pattern F and light box G.

When performing diopter detection or astigmatism detection, the inspector needs to observe the detection pattern F on the light box G through the eyepiece B, manually adjust the focusing mechanism C, so that the line on the detection pattern F exhibits the clearest state, and records the focus adjustment there. Position as a reference for diopter or astigmatism calculations. The test results of the above test steps are based on human eye observations. Since each person's eye vision difference is different from the observation habit, the results measured by different operators are different for the same test system and the same lens E to be tested. The results measured by the same operator at different times (such as morning and afternoon) are also different.

In addition, the human eye will be fatigued after a long period of focused observation, so the accuracy of long-term measurement is even more unfavorable. Since the human error can not be avoided, in the actual operation of the lens detection, multiple people and multiple detections are used to reduce the operation error. As a result, not only the detection time is lengthened, but also the detection cost is increased.

The invention relates to "optical optical automatic detecting device and method" for creating diopter, astigmatism and sharpness detection, and the main purpose thereof is to use image illuminating automatic detecting device, image analysis method for image capturing and interpretation, and automatic control technology. Auto-focusing is used to replace the personnel operation, so that the spectacle lens can be automatically detected, which greatly reduces the operator's operation error and improves the detection efficiency.

The author is characterized by: a lens automatic optical inspection device and a detection method thereof. The lens automatic optical inspection device comprises: a base, and an axial moving platform, an image sensor, a rear lens barrel, an optical mirror group, a test pattern, a lighting unit and a control unit are arranged on the base.

The base provides axial adjustment of the optical lens group and radial angle adjustment of the optical lens group, and front and rear left and right position adjustments, so that the center position of the view pattern can be aligned with the center of the image sensor; and the image sensor is connected to the back mirror The rear end of the barrel receives the image from the optical lens group; the optical lens group is composed of at least one lens and the lens barrel; the moving platform is connected with the rear lens barrel, and the image sensor and the optical mirror group are arranged when the moving platform is displaced. The relative position is changed at the same time; the test pattern is placed in front of the optical lens group, and the illumination unit is placed behind the test pattern to make the pattern produce a contrast image; the lens to be tested is placed between the optical lens group and the test pattern.

The lens automatic optical inspection method includes a method of evaluating diopter, astigmatism, and sharpness.

With the automatic optical inspection device and detection method of the lens created in this case, image acquisition and interpretation can be achieved by using image analysis method, and automatic control technology is used instead of human operation to perform auto focus, so that the astigmatism and sharpness detection of the spectacle lens can be performed. Automated testing is achieved, which significantly reduces personnel error and improves detection efficiency.

The "optical optical automatic detecting device and method" of the present invention includes: a lens automatic optical detecting device and a detecting method thereof, and referring to FIG. 2 in the same drawing, a schematic diagram of a system structure of the optical automatic detecting device of the present invention, FIG. Create an example for this case. The optometry automatic detecting device comprises: a base 1 on which an axial moving platform 2, an image sensor 3, a rear lens barrel 4, an optical lens group 5, an optical lens assembly fixing seat 5A, a test pattern 6, Lighting unit 7 and control unit 8.

The base 1 provides an axial angle adjustment of the optical lens assembly 5 and a radial angle adjustment of the optical lens assembly 5 such that the center position of the test pattern 6 can be aligned with the center of the image sensor 3.

The image sensor 3 is connected to the rear end of the rear lens barrel 4 to receive an image from the optical lens group 5. The optical lens group 5 is composed of at least one lens and a radial cylinder; the moving platform 2 is connected with the rear lens barrel 4, and when the moving platform 2 is displaced, the relative position between the image sensor 3 and the optical mirror group 5 is simultaneously changed; The test pattern 6 is placed in front of the optical lens group 5, and the illumination unit 7 is placed behind the test pattern 6, so that the test pattern 6 produces a light-dark contrast image; the lens to be tested 9 is placed between the optical lens group 5 and the test pattern 6.

Moreover, the pattern on the test pattern 6 can be any pattern, based on an illustration of the measurement step of the method of the present invention. In the description, the solar graphic test pattern and the non-sun graphic test pattern are taken as an example, but the limitation is not limited. The test pattern is only for this purpose, and any test pattern of any graphic is applicable to the case, which is stated first.

The lens automatic optical inspection method includes: (A) diopter, (B) astigmatism, and (C) resolution measurement method. among them:

(A) diopter correction and measurement:

A standard lens with two degrees of confirmation, one of which has a positive number and the other has a negative number. The data of the target image position (Dp, Dn) of the two standard lenses is first established, and the most is not installed. Clear the position of the target image (D0). Two lenses, positive (such as +0.06D) and negative (-0.06D), are usually used as standard lenses with positive and negative degrees. The lens 9 (or glasses) to be evaluated is placed in the system, and the system automatically determines the clearest target image position UD, and compares the UPD with the obtained Dp, Dn and D0 to obtain the diopter of the lens 9 to be tested. RP. The following formula can be used when comparing:

Where RP is the diopter of the lens 9 to be tested

(A1) Method for determining the clear position of the target image

The clear position of the target image is confirmed by the maximum value of the contrast index. As shown in Fig. 4, the relationship between the moving position and the contrast index is the contrast evaluation value measured by the moving platform 2 moving gradually in the same direction. Moving from position 1, the contrast value gradually increases, indicating that the clarity continues to improve. When the positions 41 and 42 are reached, the contrast indicators are 16.63 and 16.71, respectively. When the position is forwarded to position 43, the contrast index value is reduced to 16.44, which means that the best image clear position is between position 41 and position 43. As shown in Fig. 5, if the distance between the positions 41 to 43 has reached the required accuracy, the position 42 can be selected as the best position for the image. The error caused by picking the selected position 42 for the best image clear position may be too large. In this case, the curve fitting method can be used to numerically fit the original data to obtain a function type data, and then the maximum position of the function is obtained, which is the clear position of the best image, as shown in FIG.

(B) Lens astigmatism measurement: As shown in Fig. 6, the test pattern 6 is captured by the image sensor 3 and the diopter values in each direction are calculated, the maximum diopter is recorded, and the 360-degree analysis is completed, and the recorded values are sorted. The maximum diopter value, the minimum diopter value, and the diopter and astigmatism are calculated by taking the first two values of the maximum value and then analyzing the position of the image sensor corresponding to the two values before the maximum value.

Based on the further description of the different numerical values of the different test patterns in the diopter value of the test pattern, the case is illustrated by the (B1) measurement step on the solar pattern test pattern and the (B2) measurement step on the non-sun pattern test pattern. Explain, but does not limit the test pattern applicable to the creation of this case only here, and any test pattern of any pattern belongs to the applicable object of this case, hereby declare.

(B1) When the test pattern 6 uses the sun pattern test pattern:

Referring to the example shown in FIG. 6A, when the lens 9 to be tested has astigmatism, the line definition of each direction of the test pattern 6 is different, and the contrast values of the test patterns 6 in different directions at the same focus position are different, and the image sensing is moved at a fixed pitch. The device 3 (at this time, the optical lens group 5 does not move) performs image capturing. Calculate the contrast for each direction of the line along the moving direction, and then compare the obtained contrast data in each direction to obtain the maximum and minimum diopter values, which are recorded as RP1 and RP2 respectively, then the diopter RP and astigmatism A can be respectively Calculated using the following formula:

Where RP is diopter and A is astigmatism;

The steps of the actual astigmatism measurement method are as follows:

a. The tester places the lens 9 to be tested.

b. Perform image registration adjustment to adjust the test pattern 6 image to the center of the alignment reference mark on the screen.

c. When starting astigmatism measurement, the following steps are included:

C1. For the test pattern 6 center autofocus, obtain the reference position of the astigmatism measurement.

C2. Move the platform 2 back to the preset position, and then step forward with a small pitch, measure the contrast of each direction line of the test pattern 6 (as shown in Fig. 7A) at each position and record, and the contrast analysis area is the seventh. As shown in the figure, the information as shown in Fig. 8 can be obtained.

d. Calculate the diopter corresponding to the lines in each direction of the test pattern 6, and find the maximum and minimum values, which are respectively recorded as RP ₁ and RP ₂ , and calculate the diopter RP and astigmatism A using the above formula (2).

The method for establishing the astigmatism in the above c2 to retreat to the preset position is:

1. The location set by the user according to experience.

2. The position corresponding to the standard lens of the negative degree (such as -0.06D) can be corrected for the system.

(B2) When the test pattern 6 uses a non-sun graphic test pattern:

Please refer to the example shown in Figure 6B. The steps of the actual astigmatism measurement method are as follows:

a. The tester places the lens to be tested.

b. Perform image registration adjustment to adjust the test pattern image to the center of the alignment reference mark on the screen.

c. When starting astigmatism measurement, the following steps are included:

C1. For the test pattern center autofocus, obtain the reference position of the astigmatism measurement.

C2. The mobile platform retreats to the preset position, and then the image sensor moves forward with a small pitch.

C3. Capture image measurement Test the contrast of the lines in each direction of the pattern at each position and record.

C4. rotating the test pattern at a fixed interval with a set angle (as shown in FIG. 7B), repeating the c3 step until each sub-plate direction occurs at least once in a range of 360 degrees;

d. Calculate the diopter corresponding to the lines in each direction of the test pattern, and find the maximum and minimum values, which are recorded as RP ₁ and RP _{2 respectively} , and calculate the diopter RP and astigmatism A.

The method for establishing the astigmatism in the above c2 to retreat to the preset position is:

1. The location set by the user according to experience.

2. The position corresponding to the standard lens of the negative degree (such as -0.06D) can be corrected for the system.

(C) The steps of the actual measurement method of lens definition are:

1. The inspector removes all lenses.

2. Perform image registration adjustment to adjust the test pattern 6 (clear template) image to the center of the alignment reference mark on the screen.

3. Capture the image without a clear lens (as shown in Figure 10A) and record the contrast value of the user-specified area.

4. The tester places the lens 9 to be tested.

5. Perform image registration adjustment to adjust the test pattern 6 (clear template) image to the center of the alignment reference line on the screen.

6. Capture a clear image of the lens (as shown in Figure 10B) and record the contrast value of the user-specified area.

7. Compare the contrast change status of the lensless and placed lenses.

The "optical optical automatic detecting device and method" of the invention of the present invention can achieve image capturing and interpretation using image analysis methods, and replace the human operation with automatic control technology to perform auto focusing, so that the diopter, astigmatism and clearness of the spectacle lens are made. The degree of detection can achieve automated detection, which greatly reduces personnel operation errors and improves detection efficiency.

A. . . Inspector's eyes

B. . . eyepiece

C. . . Dynamic adjustment focusing mechanism

D. . . telescope

E. . . Lens to be tested

F. . . Test pattern

G. . . Light box

1. . . Base

2. . . mobile platform

3. . . Image sensor

4. . . Rear tube

5. . . Optical mirror

5A. . . Optical mirror mount

6. . . Test pattern

7. . . Lighting unit

8. . . control unit

9. . . Lens to be tested

Figure 1: Schematic diagram of the system architecture of the conventional optical inspection instrument.

Figure 2: Schematic diagram of the system architecture of the automatic optical inspection device.

Figure 3: This creative embodiment.

Fig. 4 is a diagram showing the relationship between the moving position and the contrast index of the mobile platform in the present embodiment.

Fig. 5 is a partial enlarged view of the contrast index curve of the present embodiment.

Figure 6: Flow chart of the astigmatism measurement of this creation.

Fig. 6A: Flow chart of the astigmatism measurement of the diopter values in each direction of the test pattern (the sun pattern is taken as an example).

Figure 6B: This creative captures the astigmatism measurement flow chart for the diopter values in each direction of the test pattern (non-sun graphics).

Fig. 7: The contrast evaluation of the astigmatism measurement of the present embodiment refers to the measurement area.

Fig. 7A is a test pattern (original position) of the astigmatism measurement of the present embodiment.

Fig. 7B is a view showing a test pattern of astigmatism measurement in the present embodiment (a schematic example of a rotation setting angle).

Fig. 8 is a graph showing the contrast of the angle lines of the test pattern of the astigmatism measurement result of the present embodiment.

Figure 9A: The astigmatism measurement of the present embodiment captures the minimum diopter position of the image.

Figure 9B: The astigmatism measurement of the present embodiment captures the average diopter position of the image.

Figure 9C: The astigmatism measurement of the present embodiment captures the maximum diopter position of the image.

Figure 10A: This creation example has no clear image of the lens.

Figure 10B: This creation example adds a clear template image of the lens to be tested.

1. . . Base

2. . . mobile platform

3. . . Image sensor

4. . . Rear tube

5. . . Optical mirror

5A. . . Optical mirror mount

6. . . Test pattern

7. . . Lighting unit

8. . . control unit

9. . . Lens to be tested

Claims (10)

An automatic optical spectroscopy device uses an optical optometry automatic detecting device to perform image capturing and interpretation using an image analysis method, and an automatic control technology to replace the human operation for auto focusing, so that the spectacle lens can be automatically detected; The automatic optical inspection device comprises a base, and an axial movement platform, an image sensor, a rear lens barrel, an optical lens group, a test pattern, a lighting unit and a control unit are arranged on the base; wherein the base provides an axial angle of the optical lens group Adjusting and adjusting the radial angle of the optical lens group so that the center position of the viewing pattern can be aligned with the center of the image sensor; the image sensor is connected to the rear end of the rear lens barrel to receive the image from the optical lens group; the optical lens group The mobile platform is connected with the rear barrel; the relative position between the image sensor and the optical mirror changes simultaneously when the moving platform is displaced; the test pattern is placed in front of the optical mirror, and the illumination is The unit is placed behind the test pattern to create a contrast image of the pattern; the lens to be tested is placed in the optical Between the group and the test pattern. An automatic method for detecting optometry is a method for measuring the astigmatism of a lens to be tested. The image sensor is used to capture the test pattern and calculate the diopter value in each direction, and the maximum value of the diopter is recorded and the 360-degree analysis is completed. Sorting to capture the first two values of the maximum value, and then analyzing the position of the image sensor corresponding to the two values before the maximum value, thereby calculating the maximum diopter value, the minimum diopter value, and the diopter and astigmatism; the astigmatism measurement method is: When the lens to be tested has astigmatism, the line definition of each direction of the test pattern is different. The contrast values of the test patterns in different directions at the same focus position are different. The image sensor is moved at a fixed pitch for image capture, which is larger along the moving direction. The range is calculated for each direction of the line, and then the contrast data obtained in each direction is compared to obtain the maximum and minimum diopter values, which are recorded as RP1 and RP2, respectively, and the diopter RP and astigmatism A are calculated, and the calculation can be utilized. The following formula is calculated: According to the method of claim 2, the astigmatism measuring step is: a. the detecting person places the lens to be tested; b. performs the image alignment adjustment, and adjusts the test pattern image to the screen. Bit reference center line; c. When starting astigmatism measurement, the following steps are included: c1. For the test pattern center autofocus, obtain the reference position of astigmatism measurement; c2. Move the platform back to the preset position, and then gradually step to small pitch Before, measure the contrast of the lines in each direction of the test pattern at each position, and record; d. Calculate the diopter corresponding to the lines in each direction of the test pattern, and find the maximum and minimum values, which are respectively recorded as RP ₁ and RP ₂ And calculate the diopter RP and astigmatism. According to the method of claim 2, the astigmatism measuring step is: a. the detecting person places the lens to be tested; b. performs the image alignment adjustment, and adjusts the test pattern image to the screen. The center of the reference mark line; c. When starting the astigmatism measurement, the following steps are included: c1. autofocus for the test pattern center, obtain the reference position of the astigmatism measurement; c2. the mobile platform retreats to the preset position, and then the image sensor Gradually move the small pitch forward, c3. Capture the image measurement at each position to test the contrast of the lines in each direction of the pattern, and record; c4. Take the center of the test pattern as the center of rotation, and rotate the angle of the test pattern at regular intervals, repeat Step c3, until each sub-plate direction appears at least once in the range of 360 degrees; d. Calculate the diopter corresponding to the lines in each direction of the test pattern, and find the maximum and minimum values thereof, respectively, as RP ₁ and RP ₂ , and Calculate the diopter RP and astigmatism. According to the method of automatic detection of optics according to item 2 of the patent application scope, the diopter detection system uses a standard lens confirmed by two degrees, one of which has a positive degree and the other has a negative degree, and the first two standard lenses are first established. The data of the target image position (Dp, Dn), and the position of the clearest target image (D0) when no lens is installed, the lens to be evaluated is placed in the detection device system, and the system automatically determines the clearest target The image position UD, the UPD is compared with the obtained Dp, Dn and D0 to obtain the diopter RP of the lens to be tested, and the following formula can be used for comparison: According to the automatic method for detecting optics according to item 5 of the patent application scope, the method for determining the clear position of the target image is to confirm the clear position of the target image by the maximum value of the contrast index, that is, the mobile platform gradually moves in the same direction. The measured contrast evaluation value is obtained to obtain the best image clear position. When the error generated by the clear position of the optimal image may be too large, the curve fitting method may be used to numerically fit the original data to obtain a functional type. The data, and then the maximum position of the function, is the best image clear position. According to the automatic method for detecting optics according to items 3 and 4 of the patent application scope, the method for receding the astigmatism to the preset position can be determined by the user according to the position set by the experience or the position of the system diopter when the negative lens corresponds to the position of the standard lens. A method for automatically detecting spectacles is a method for measuring the sharpness of a lens to be tested; the resolution measuring step is: a. the detecting personnel remove all the lenses; b. performing the image alignment adjustment, and the test pattern is Clear template) image is adjusted to the center of the alignment reference mark on the screen; c. captures the image without the lens clear sample, records the contrast value of the user specified area; d. the tester places the lens to be tested; e. performs image alignment adjustment Adjust the test pattern (clear template) image to the center of the alignment reference mark on the screen; f. capture the clear image of the lens and record the contrast value of the specified area of the user; g. compare the contrast change status of the lens without the lens . An automatic method for detecting optometry is a diopter detection of a lens. A standard lens confirmed by two degrees is used, one of which has a positive number and the other has a negative number. First, the standard lens position of the two standard lenses is first established. The data (Dp, Dn), and the position of the clearest target image (D0) when no lens is installed, the lens to be evaluated is placed in the detection device system, and the system automatically determines the clearest target image position UD, The UPD is compared with the obtained Dp, Dn and D0 to obtain the diopter RP of the lens to be tested. The following formula can be used for comparison: According to the spectacles automatic detection method described in claim 9, wherein the method for determining the clear position of the target image is to confirm the clear position of the target image by the maximum value of the contrast index, that is, the mobile platform gradually moves in the same direction. The measured contrast evaluation value is obtained to obtain the best image clear position. When the error generated by the clear position of the optimal image may be too large, the curve fitting method may be used to numerically fit the original data to obtain a functional type. The data, and then the maximum position of the function, is the best image clear position.