Optical machine platform inspection method
1. An optical machine inspection method is characterized by comprising the following steps:
(a) designing a gray scale adjustable uniform light source array to measure gray scale brightness change information provided by a light source;
(b) inputting a test pattern by the gray scale adjustable uniform light source array;
(c) calculating an actual brightness according to the test pattern;
(d) an optical machine to be tested shoots the test pattern and obtains a capturing brightness after calculation; and
(e) and generating an evaluation of whether the optical machine to be tested needs to be corrected according to the difference between the actual brightness and the captured brightness.
2. The method of claim 1, further comprising:
(f) automatically perform calibration to provide correct photographing environment of the optical machine.
3. The method of claim 1, wherein the light source is a laser, a light emitting diode, a cold cathode fluorescent lamp, or other light sources.
4. The method as claimed in claim 1, wherein when the gray scale tunable uniform light source array is designed to be transmissive, the gray scale tunable uniform light source array includes a first lens, a second lens and a transmissive unit, and light emitted from the light source sequentially passes through the first lens, the second lens and the transmissive unit and is emitted to the optical apparatus to be tested.
5. The method of claim 1, wherein when the gray scale tunable uniform light source array is designed as a vertical reflection type, the gray scale tunable uniform light source array includes a first lens, a second lens and a vertical reflection unit, and light emitted from the light source passes through the first lens and the second lens in sequence and is then vertically reflected by the vertical reflection unit to the optical apparatus under test.
6. The method of claim 1, wherein when the gray scale tunable uniform light source array is designed to be an oblique reflection type, the gray scale tunable uniform light source array includes a first lens, a second lens and an oblique reflection unit, and light emitted from the light source passes through the first lens and the second lens in sequence and then is reflected by the oblique reflection unit to the optical apparatus under test.
7. The method as claimed in claim 1, wherein when the gray scale tunable uniform light source array is designed as a light homogenizer, the gray scale tunable uniform light source array includes a first lens, a first light homogenizer, a second lens and a transmission unit, and light emitted from the light source sequentially passes through the first lens, the first light homogenizer, the second lens and the transmission unit and then is emitted to the optical stage to be tested.
8. The method as claimed in claim 1, wherein when the gray scale tunable uniform light source array is designed as a light guide plate, the gray scale tunable uniform light source array comprises a light guide plate, a diffuser and a transparent module, and light emitted from the light source sequentially passes through the light guide plate, the diffuser and the transparent module and is then emitted to the optical apparatus to be tested.
9. The method as claimed in claim 1, wherein when the gray scale tunable uniform light source array is designed as a light guide pillar type, the gray scale tunable uniform light source array includes a light guide pillar and a transparent module, and light emitted from the light source sequentially passes through the light guide pillar and the transparent module and then is emitted to the optical apparatus to be tested.
10. The method of claim 1, wherein step (c) is performed by scaling the test pattern with an optical transfer function to generate the actual brightness.
11. The method of claim 1, wherein step (e) comprises the steps of:
(e1) calculating a difference graph of the actual brightness and the captured brightness; and
(e2) the difference graph is analyzed by an algorithm and an evaluation whether the optical machine to be tested needs to be corrected is generated according to the analysis result.
12. The method of claim 11, wherein the step (e2) is performed to generate an evaluation of the calibration required for setting the integration range parameter of the optical apparatus to be tested when the difference pattern has a fine moire signal.
13. The method of claim 11, wherein the step (e2) is performed to generate an evaluation of the focus parameter setting of the optical apparatus to be tested to be corrected when the difference pattern has a large moire signal.
14. The method as claimed in claim 11, wherein the step (e2) comprises evaluating the exposure time setting of the optical stage to be inspected for correction when the difference pattern has local brightness unevenness.
15. The method as claimed in claim 11, wherein the step (e2) is performed to generate an evaluation that the setting of the uniform field of the optical apparatus to be tested needs to be corrected when the difference pattern has a large range of brightness unevenness.
Background
Generally, an optical apparatus generally includes two main components, a lens and a sensor, and the main task of the optical apparatus is data acquisition. The lens is used for converting the object space information into an image space plane. The conversion process is easily affected by Vignetting (Vignetting), cosine distribution, lens Distortion (Distortion) to cause pixel displacement, and other factors, and the lens needs to be corrected. The sensor is used for converting the optical signal of the image space plane into an electric signal and then converting the electric signal into a digital signal. Factors such as exposure time and moire patterns need to be considered in this conversion process.
For example, if the exposure time is too short, the noise ratio is too low, so that the quality of the optical data is not good, and the compensation fineness is easily reduced; on the other hand, if the exposure time is too long, the portion with high optical brightness is easily saturated, which causes local compensation abnormality. Moire is related to the sampling frequency, and is removed by the optical factory because the spatial frequencies of the panel and the sensor generate sum and difference frequencies, and the sum frequency is easily sampled and observed within the Nyquist frequency, resulting in Moire at high gray levels.
In addition, the following problems may be encountered during the data acquisition process of the optical bench: if the lens factory adds the algorithm into the optical machine by itself, the compensation may cause the phenomenon of sandy brightness unevenness (Mura), which needs to be corrected; if the optical machine is not coaxial with the panel during shooting, the optical data has a skew problem and needs to be corrected; if the average brightness of the optical data provided by the optical bench does not fall on the Gamma curve, which represents that the optical data is wrong, the setting during shooting may be problematic and needs to be corrected.
However, the conventional optical apparatus detection device usually has a poor shooting effect when shooting a periodic object, but no other device can prove that the detection device has a problem, and no problem is found, which results in the optical apparatus collecting wrong data to affect subsequent applications, such as brightness uniformity removal (Demura), and the like, and needs to be improved.
Disclosure of Invention
In view of the above, the present invention provides a method for inspecting an optical apparatus to effectively solve the above-mentioned problems encountered in the prior art.
An embodiment of the invention is a method for inspecting an optical bench. In this embodiment, the method comprises the steps of: (a) designing a gray scale adjustable uniform light source array to measure gray scale brightness change information provided by a light source; (b) inputting a test pattern by a gray scale adjustable uniform light source array; (c) calculating actual brightness according to the test pattern; (d) shooting a test pattern by an optical machine to be tested and calculating to obtain captured brightness; (e) generating an evaluation of whether the optical machine to be tested needs to be corrected according to the difference between the actual brightness and the captured brightness; and (f) automatically correcting to provide a correct shooting environment of the optical machine.
In one embodiment, the light source may be a laser, a Light Emitting Diode (LED), a Cold Cathode Fluorescent Lamp (CCFL), or other light source.
In an embodiment, when the gray-scale tunable uniform light source array is designed to be transmissive, the gray-scale tunable uniform light source array includes a first lens, a second lens and a transmissive unit, and light emitted from the light source is emitted to the optical apparatus to be tested through the first lens, the second lens and the transmissive unit in sequence.
In an embodiment, when the gray scale tunable uniform light source array is designed as a vertical reflection type, the gray scale tunable uniform light source array includes a first lens, a second lens and a vertical reflection unit, and light emitted from the light source passes through the first lens and the second lens in sequence and is then vertically reflected by the vertical reflection unit to the optical machine to be tested.
In an embodiment, when the gray scale tunable uniform light source array is designed to be an oblique reflection type, the gray scale tunable uniform light source array includes a first lens, a second lens and an oblique reflection unit, and light emitted from the light source sequentially passes through the first lens and the second lens and then is obliquely reflected by the oblique reflection unit to the optical machine to be tested.
In an embodiment, when the gray scale adjustable uniform light source array is designed to be a light homogenizer, the gray scale adjustable uniform light source array includes a first lens, a first light homogenizer, a second lens and a penetration unit, and light emitted from the light source sequentially passes through the first lens, the first light homogenizer, the second lens and the penetration unit and then is emitted to the optical machine to be tested.
In an embodiment, when the gray-scale tunable uniform light source array is designed as a light guide plate type, the gray-scale tunable uniform light source array includes a light guide plate, a diffusion sheet and a transparent module, and light emitted from the light source sequentially passes through the light guide plate, the diffusion sheet and the transparent module and then is emitted to the optical machine to be tested.
In an embodiment, when the gray-scale tunable uniform light source array is designed as a light guide pillar type, the gray-scale tunable uniform light source array includes a light guide pillar and a transparent module, and light emitted from the light source sequentially passes through the light guide pillar and the transparent module and then is emitted to the optical machine to be tested.
In one embodiment, step (c) is to convert the test pattern into an actual brightness through an optical transfer function.
In one embodiment, step (e) comprises the steps of: (e1) calculating a difference graph of the actual brightness and the captured brightness; and (e2) analyzing the difference pattern by an algorithm and generating an evaluation of whether the optical bench to be tested needs to be corrected according to the analysis result.
In one embodiment, when the difference pattern has a fine moire signal, the step (e2) generates an evaluation that the setting of the integration range parameter of the optical apparatus to be measured needs to be corrected.
In one embodiment, when the difference pattern has a large range of moire signals, the step (e2) generates an evaluation that the setting of the focus parameter of the optical apparatus to be measured needs to be corrected.
In one embodiment, when the difference pattern has local brightness unevenness, the step (e2) generates an evaluation that the setting of the exposure time of the optical apparatus to be measured needs to be corrected.
In one embodiment, when the difference pattern has a large-scale brightness unevenness, the step (e2) is performed
Compared with the prior art, the invention provides the optical machine inspection method which can obtain a difference graph between the actual brightness generated by the test pattern through optical conversion function conversion and the captured brightness obtained by shooting the test pattern and calculating the test pattern by the optical machine to be tested, and then analyze whether the difference graph is abnormal or not through an algorithm so as to judge whether the parameter setting of the optical machine to be tested needs to be corrected or not. Therefore, the optical machine inspection method can achieve the specific effect of quickly inspecting the optical machine to be inspected, and can correct the parameter setting of the optical machine to be inspected according to the inspection result so as to eliminate the abnormity.
The advantages and spirit of the present invention can be further understood by the following detailed description of the invention and the accompanying drawings.
Drawings
FIG. 1 is a flow chart of a method for inspecting an optical tool according to a preferred embodiment of the present invention.
Fig. 2A is a schematic diagram corresponding to step S10 in fig. 1.
FIG. 2B is a diagram corresponding to steps S12-S16 in FIG. 1.
FIG. 3 is a schematic diagram of a transmissive gray scale tunable uniform light source array.
FIG. 4 is a schematic diagram of a gray scale tunable uniform light source array designed as a vertical reflection type.
FIG. 5 is a schematic diagram of a gray scale tunable uniform light source array designed as a slant reflection type.
FIG. 6 is a schematic diagram of a gray scale tunable uniform light source array designed as a light uniformizing type.
FIG. 7 is a schematic diagram of a gray scale tunable uniform light source array designed as a light guide plate.
FIG. 8 is a schematic diagram of a gray scale tunable uniform light source array designed as a light guide pillar.
FIG. 9 is a flowchart illustrating that step S18 of FIG. 1 further includes steps S18A-S18B.
Fig. 10A to 10C are schematic diagrams respectively illustrating that when the difference pattern has brightness unevenness (Mura), the exposure time can be increased and the brightness unevenness can be effectively removed after correction.
Fig. 11A to 11B are schematic diagrams respectively illustrating that when the difference pattern does not have brightness unevenness (Mura), no correction is required.
Description of the main element symbols:
S10-S20
Light source array with adjustable gray scale
PC.
TP.. test pattern
Optical machine to be tested
PC1
PC2
CB.. capturing brightness
Actual brightness
Gray scale adjustable uniform light source array
LS.. light source
First lens in ln1
A second lens
PT.
Gray scale adjustable uniform light source array
VR.. vertical reflection unit
Gray scale adjustable uniform light source array
Oblique reflection unit
6. gray scale adjustable uniform light source array
First light homogenizer
H2
Gray scale adjustable uniform light source array
LG.. light guide plate
Diffusion sheet
Gray scale adjustable uniform light source array
LP.. light guide column
S18A-S18B
Uneven brightness
Detailed Description
Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. The same or similar numbered elements/components used in the drawings and the embodiments are used to represent the same or similar parts.
An embodiment of the invention is a method for inspecting an optical bench. In this embodiment, the method for inspecting an optical apparatus is used to quickly inspect whether the optical apparatus to be inspected is abnormal, and the parameter setting of the optical apparatus to be inspected can be corrected according to the inspection result to eliminate the abnormality, but not limited thereto.
Referring to fig. 1, fig. 1 is a flowchart of an optical apparatus inspection method in this embodiment. As shown in fig. 1, the method for inspecting an optical apparatus in this embodiment may include the following steps:
step S10: designing a gray scale adjustable uniform light source array to measure gray scale brightness change information provided by a light source;
step S12: inputting a test pattern by a gray scale adjustable uniform light source array;
step S14: calculating actual brightness according to the test pattern;
step S16: shooting a test pattern by an optical machine to be tested and calculating to obtain captured brightness;
step S18: generating an evaluation of whether the optical machine to be tested needs to be corrected according to the difference between the actual brightness and the captured brightness; and
step S20: automatically perform calibration to provide correct photographing environment of the optical machine.
Referring to fig. 2A, fig. 2A is a schematic diagram corresponding to step S10 in fig. 1. As shown in fig. 2A, the method for inspecting an optical bench of the present invention can design a gray-scale adjustable uniform light source array ULA to measure gray-scale luminance variation information (optical transfer function) provided by a light source through a computer PC.
Referring to fig. 2B, fig. 2B is a schematic diagram corresponding to steps S12-S16 in fig. 1. As shown in fig. 2B, the method for inspecting an optical apparatus of the present invention can input a test pattern TP into the gray-scale adjustable uniform light source array ULA, and calculate the actual luminance AB by the computer PC1 according to the test pattern TP and obtain the captured luminance CB by the computer PC2 after the test pattern TP is photographed by the optical apparatus DUT to be inspected.
Referring to fig. 3, fig. 3 is a schematic diagram of a transmissive gray scale tunable uniform light source array. As shown in fig. 3, when the gray-scale tunable uniform light source array 3 is designed to be transmissive, the gray-scale tunable uniform light source array 3 includes a first lens LN1, a second lens LN2, and a transmissive unit PT, and light emitted from the light source LS is sequentially emitted to the optical machine under test DUT through the first lens LN1, the second lens LN2, and the transmissive unit PT. It should be noted that the transmissive unit PT may be a Liquid Crystal Display (LCD) or a Spatial Light Modulator (SLM), but is not limited thereto.
Referring to FIG. 4, FIG. 4 is a schematic diagram of a gray scale tunable uniform light source array designed as a vertical reflection type. As shown in fig. 4, when the gray-scale tunable uniform light source array 4 is designed to be a vertical reflection type, the gray-scale tunable uniform light source array 4 includes a first lens LN1, a second lens LN2 and a vertical reflection unit VR, and light emitted from the light source LS passes through the first lens LN1 and the second lens LN2 in sequence and is then vertically reflected by the vertical reflection unit VR to the optical machine under test DUT. It should be noted that the vertical reflection unit VR may be a Polarization Beam Splitter (PBS), but is not limited thereto.
Referring to fig. 5, fig. 5 is a schematic diagram of the gray scale tunable uniform light source array 5 designed as an oblique reflection type. As shown in fig. 5, when the gray-scale tunable uniform light source array 5 is designed to be an oblique reflection type, the gray-scale tunable uniform light source array 5 includes a first lens LN1, a second lens LN2 and an oblique reflection unit DMD, and light emitted from the light source LS passes through the first lens LN1 and the second lens LN2 in sequence and is reflected obliquely by the oblique reflection unit DMD to the optical bench DUT to be tested. It should be noted that the oblique reflective unit DMD may be a Digital Micromirror Device (DMD), but is not limited thereto.
Referring to fig. 6, fig. 6 is a schematic diagram of a gray scale tunable uniform light source array designed as a light uniformizing type. As shown in fig. 6, when the gray scale tunable uniform light source array 6 is designed as a light homogenizer type, the gray scale tunable uniform light source array 6 includes a first lens LN1, a first light homogenizer H1, a second light homogenizer H2, a second lens LN2 and a penetration unit PT, and light emitted from the light source LS sequentially passes through the first lens LN1, the first light homogenizer H1, the second light homogenizer H2, the second lens LN2 and the penetration unit PT and then is emitted to the optical machine under test DUT. The first light homogenizer H1 and the second light homogenizer H2 may be formed by adjacently arranging a plurality of lenses, but not limited thereto.
Referring to fig. 7, fig. 7 is a schematic diagram illustrating a gray scale adjustable uniform light source array designed as a light guide plate. As shown in fig. 7, when the gray-scale tunable uniform light source array 7 is designed as a light guide plate type, the gray-scale tunable uniform light source array 7 includes a light guide plate LG, a diffusion sheet DF and a penetration unit PT, and light emitted from the light source LS sequentially passes through the light guide plate LG, the diffusion sheet DF and the penetration unit PT and then is emitted to the optical bench DUT to be tested, but not limited thereto. It should be noted that the light source LS may be disposed outside the light incident side of the light guide plate LG, so that the light emitted from the light source LS is incident into the light guide plate LG from the light incident side of the light guide plate LG, and is focused by the light focusing units disposed in the light guide plate LG and then emitted to the diffuser DF disposed outside the light emitting side of the light guide plate LG, and the light emitting side and the light incident side are perpendicular to each other, but not limited thereto.
Referring to fig. 8, fig. 8 is a schematic view of a gray scale adjustable uniform light source array designed as a light guide pillar type. As shown in fig. 8, when the gray scale adjustable uniform light source array 8 is designed as a light guide pillar type, the gray scale adjustable uniform light source array 8 includes a light guide pillar LP and a penetration unit PT, and light emitted from the light source LS sequentially passes through the light guide pillar LP and the penetration unit PT and then is emitted to the optical device under test DUT. It should be noted that the light source LS may be disposed outside the light incident side of the light guide pillar LP, so that the light emitted from the light source LS is incident into the light guide pillar LP from the light incident side of the light guide pillar LP and is emitted to the penetrating unit PT located outside the light emitting side of the light guide pillar LP, and the light emitting side and the light incident side of the light guide pillar LP are disposed opposite to each other, but not limited thereto.
It should be noted that, in practical applications, different design methods can be adopted to design the gray-scale adjustable uniform light source array ULA according to different requirements, and the above embodiments only list the design methods that are frequently used, but are not limited thereto.
Referring to fig. 9, fig. 9 is a flowchart illustrating that step S18 of fig. 1 further includes steps S18A to S18B. As shown in fig. 9, step S18 may include:
step S18A: calculating a difference graph of the actual brightness and the captured brightness; and
step S18B: and analyzing the difference graph by an algorithm and generating the evaluation whether the optical machine to be tested needs to be corrected or not according to the analysis result.
In an embodiment, when the difference pattern calculated in step S18A has a fine moire signal, step S18B analyzes the difference pattern by an algorithm and generates an evaluation that the setting of the integration range parameter of the optical apparatus to be measured needs to be corrected according to the analysis result, so as to inform the user that the setting of the integration range parameter of the optical apparatus to be measured needs to be corrected.
In another embodiment, when the difference pattern calculated in step S18A has a moire signal with a wide range, step S18B analyzes the difference pattern by an algorithm and generates an evaluation that the setting of the focusing parameter of the optical apparatus to be tested needs to be corrected according to the analysis result, so as to inform the user that the setting of the focusing parameter of the optical apparatus to be tested needs to be corrected.
In another embodiment, when the difference pattern calculated in step S18A has local brightness unevenness, step S18B analyzes the difference pattern by an algorithm and generates an evaluation that the setting of the exposure time of the optical apparatus to be measured needs to be corrected according to the analysis result, so as to notify the user that the setting of the exposure time of the optical apparatus to be measured needs to be corrected.
In another embodiment, when the difference pattern calculated in step S18A has a large range of brightness unevenness, step S18B analyzes the difference pattern by an algorithm and generates an evaluation that the setting of the uniform field of the optical apparatus to be tested needs to be corrected according to the analysis result, so as to notify the user that the setting of the uniform field of the optical apparatus to be tested needs to be corrected.
It should be noted that, in the embodiment of step S18, only the problems that often occur in the optical bench are listed, but not limited thereto.
When the difference pattern calculated in step S18A has an abnormal pattern (as shown in fig. 10B), step S18B may analyze the difference pattern by an algorithm and generate an evaluation that the setting of the optical apparatus to be tested needs to be corrected according to the analysis result, so as to notify the user that the setting of the optical apparatus to be tested needs to be corrected.
Therefore, the user can perform correction, for example, correction for increasing the exposure time, and then effectively remove the brightness unevenness (as shown in fig. 10C). On the contrary, when the difference pattern calculated in step S18A does not have uneven brightness (as shown in fig. 11B), the user does not need to correct the optical stage to be measured.
Compared with the prior art, the invention provides the optical machine inspection method which can obtain a difference graph between the actual brightness generated by the test pattern through optical conversion function conversion and the captured brightness obtained by shooting the test pattern and calculating the test pattern by the optical machine to be tested, and then analyze whether the difference graph is abnormal or not through an algorithm so as to judge whether the parameter setting of the optical machine to be tested needs to be corrected or not. Therefore, the optical machine inspection method can achieve the specific effect of quickly inspecting the optical machine to be inspected, and can correct the parameter setting of the optical machine to be inspected according to the inspection result so as to eliminate the abnormity.