Polarizing axis position detection device and polarizing axis position detection method

Abstract

This invention discloses a polarizing axis detection device and method, comprising two polarizers, two photoelectric sensors, a standard polarizer, a rotating assembly, a light source, and a processor. The polarization directions of the two polarizers are at an angle of 45°. The standard polarizer is mounted on the rotating assembly. The light source is located on one side of the standard polarizer and uniformly illuminates it. The two polarizers are located on the other side of the standard polarizer and are on the same plane. The projection of the standard polarizer onto the same plane covers both polarizers. The two photoelectric sensors are respectively mounted on the side of the two polarizers away from the light source. The processor is communicatively connected to each of the two photoelectric sensors. This invention can detect the axis deviation of polarizing lenses more quickly and accurately.

Description

Technical Field

[0001] This invention relates to the field of optical lens testing technology, and in particular to a polarization axis detection device and a polarization axis detection method. Background Technology

[0002] Polarized sunglasses fall under the category of personal eye and face protection products. The technical indicators for evaluating their quality mainly focus on several aspects, including polarization degree, UV protection, resistance to mechanical impact, transmittance, and composite strength. Among these, polarization degree is a crucial indicator. According to relevant international standards, the polarization degree of polarized sunglasses products generally needs to be controlled within ±5 degrees. Substandard polarized sunglasses not only harm the user's eye health but also affect consumer interests. Therefore, polarized sunglasses manufacturers typically require strict polarization axis (polarization degree) measurement before production.

[0003] Currently available digital polarization axis testers incorporate a semi-shadow polarizer and a light source. The polarization directions of the upper and lower halves of the semi-shadow polarizer are at angles of ±3° to the horizontal. During testing, the glasses under test are fixed in the testing position, and the internal light source is turned on. The light passes through the semi-shadow polarizer and illuminates the polarized lenses of the glasses evenly. The tester observes the brightness of the upper and lower halves of the light source through an observation hole at the top front of the tester. If they are different, it indicates an axis deviation in the polarized lenses of the glasses under test. In this case, the tester needs to adjust the angle of the glasses under test to make the brightness of the upper and lower halves of the light source the same. Finally, the axis deviation of the polarized lenses is obtained through digital reading. However, this method of manually observing brightness is inefficient and lacks accuracy. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a polarizing axis detection device and a polarizing axis detection method, which can detect the axis deviation of polarizing lenses more quickly and accurately.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a polarization axis detection device, comprising a polarization component, a photoelectric sensor component, a standard polarizer, a rotation component, a light source and a processor, wherein the polarization component comprises a first polarizer and a second polarizer, and the included angle between the polarization directions of the first polarizer and the second polarizer is 45°, and the photoelectric sensor component comprises a first photoelectric sensor and a second photoelectric sensor.

[0006] The standard polarizer is disposed on the rotating assembly, which drives the standard polarizer to rotate. The light source is located on one side of the standard polarizer and illuminates it uniformly. The first polarizer and the second polarizer are located on the other side of the standard polarizer and are on the same plane. The projection of the standard polarizer onto the same plane covers the first polarizer and the second polarizer. The first photoelectric sensor is disposed on the side of the first polarizer away from the light source. The second photoelectric sensor is disposed on the side of the second polarizer away from the light source. The processor is communicatively connected to the first photoelectric sensor and the second photoelectric sensor.

[0007] The present invention also proposes a polarization axis detection method based on the polarization axis detection device described above, comprising:

[0008] By controlling the rotating component, the standard polarizer is rotated. During the rotation, the rotation angle and the voltage signals output by the first and second photoelectric sensors are acquired in real time. The correlation between the rotation angle and the first and second voltage values ​​is obtained. Based on the voltage signals output by the first and second photoelectric sensors, the highest and lowest voltage values ​​are calibrated. The rotation angle is the angle between the polarization direction of the standard polarizer and the polarization direction of the second polarizer.

[0009] The standard polarizer is replaced with the lens under test, the ideal polarization direction of the lens under test is the same as the polarization direction of the second polarizer, and the voltage signals output by the first photoelectric sensor and the second photoelectric sensor are obtained to obtain the third voltage value and the fourth voltage value, which are used as the current third voltage value and the current fourth voltage value.

[0010] Based on the correlation between the first voltage value and the rotation angle, the rotation angle corresponding to the current third voltage value is obtained as the current rotation angle, and based on the correlation between the rotation angle and the second voltage value, the second voltage value corresponding to the current rotation angle is obtained;

[0011] Calculate the average of the current fourth voltage value and the corresponding second voltage value as the current average value, and calculate the current ratio value based on the current average value and the current fourth voltage value;

[0012] Determine whether the absolute value of the difference between the current ratio and 1 is less than a preset threshold;

[0013] If so, the current rotation angle will be used as the final polarization axis error angle;

[0014] If not, then the new third voltage value and the new fourth voltage value are calculated based on the current third voltage value, the current fourth voltage value, the current ratio value, the highest voltage value, and the lowest voltage value.

[0015] The new third voltage value and the new fourth voltage value are respectively used as the current third voltage value and the current fourth voltage value. The steps of obtaining the rotation angle corresponding to the current third voltage value based on the correlation between the first voltage value and the rotation angle, and obtaining the second voltage value corresponding to the current rotation angle based on the correlation between the rotation angle and the second voltage value are continued.

[0016] The beneficial effects of this invention are as follows: Light emitted from the light source passes sequentially through a standard polarizer and a polarizing assembly. By rotating the standard polarizer, the angle between its polarization direction and the polarization directions of the two polarizers in the polarizing assembly changes. During this process, the voltage signals collected by the two photoelectric sensors also change periodically. By real-time acquisition of the rotation angle of the standard polarizer's polarization direction relative to the polarization direction of the second polarizer, as well as the voltage signals output by the two photoelectric sensors, two voltage values ​​corresponding to each rotation angle can be calibrated and recorded as a reference table. When testing the glasses under test, the standard polarizer is removed, replaced with the glasses under test, and the voltage values ​​output by the photoelectric sensors are read and analyzed based on the reference table to determine the axis deviation of the lens under test. This invention eliminates the need for manual observation of brightness levels, enabling faster and more accurate detection of the axis deviation of polarized lenses. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the polarization axis detection device of the present invention;

[0018] Figure 2 This is a schematic diagram of the polarization direction of the first polarizer and the second polarizer in Embodiment 1 of the present invention;

[0019] Figure 3 This is a schematic diagram of the polarization axis detection device according to Embodiment 1 of the present invention. Figure 1 ;

[0020] Figure 4 This is a top view of the first placement platform according to Embodiment 1 of the present invention (with the rotary motor and angle sensor hidden);

[0021] Figure 5 This is a schematic diagram of the polarization axis detection device according to Embodiment 1 of the present invention. Figure 2 (Hide rotating components);

[0022] Figure 6 This is the polarization axis detection method of Embodiment 2 of the present invention;

[0023] Figure 7 This is a comparison table of Embodiment 2 of the present invention;

[0024] Figure 8 This is a schematic diagram of the voltage signal output by the photoelectric sensor component in step S1 of embodiment two of the present invention;

[0025] Figure 9 This is a schematic diagram of the voltage signal output by the photoelectric sensor assembly when the lens under test rotates, as shown in Embodiment 2 of the present invention.

[0026] Label Explanation:

[0027] 1. Polarizing assembly; 2. Photoelectric sensor assembly; 3. Standard polarizer; 4. Rotation assembly; 5. Light source; 6. Processor; 7. Frame; 8. Angle sensor;

[0028] 11. First polarizer; 12. Second polarizer;

[0029] 21. First photoelectric sensor; 22. Second photoelectric sensor;

[0030] 41. Rotary motor; 42. Driving shaft; 43. Rotating ring; 44. Driven shaft; 45. First gear; 46. Second gear; 47. Third gear;

[0031] 71. First placement platform; 72. Second placement platform;

[0032] 711. Inner cavity; 712. First through groove; 713. Second through groove; 714. Third through groove; 715. Fourth through groove;

[0033] 721. Polarizing component placement slot. Detailed Implementation

[0034] To explain the technical content, objectives, and effects of the present invention in detail, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0035] Please see Figure 1 A polarizing axis detection device includes a polarizing component, a photoelectric sensor component, a standard polarizer, a rotating component, a light source, and a processor. The polarizing component includes a first polarizer and a second polarizer, and the included angle between the polarization directions of the first polarizer and the second polarizer is 45°. The photoelectric sensor component includes a first photoelectric sensor and a second photoelectric sensor.

[0036] The standard polarizer is disposed on the rotating assembly, which drives the standard polarizer to rotate. The light source is located on one side of the standard polarizer and illuminates it uniformly. The first polarizer and the second polarizer are located on the other side of the standard polarizer and are on the same plane. The projection of the standard polarizer onto the same plane covers the first polarizer and the second polarizer. The first photoelectric sensor is disposed on the side of the first polarizer away from the light source. The second photoelectric sensor is disposed on the side of the second polarizer away from the light source. The processor is communicatively connected to the first photoelectric sensor and the second photoelectric sensor.

[0037] As can be seen from the above description, the beneficial effect of the present invention is that it eliminates the need for manual observation of brightness and darkness, and can detect the axis deviation of polarizing lenses more quickly and accurately.

[0038] Furthermore, it also includes an angle sensor connected to the rotating assembly and communicatively connected to the processor.

[0039] As described above, by setting an angle sensor to detect the rotation angle, automatic monitoring of the rotation angle can be achieved.

[0040] Furthermore, the rotating assembly includes a rotary motor, a drive shaft, and a rotating ring. The standard polarizer is disposed in the rotating ring, the rotating ring is connected to the drive shaft, and the drive shaft is connected to the rotary motor.

[0041] As described above, when the output shaft of the rotary motor rotates, it synchronously drives the active rotating shaft to rotate, which in turn drives the rotating ring to rotate, thereby causing the standard polarizer in the rotating ring to rotate.

[0042] Furthermore, the outer surface of the active rotating shaft is provided with a first gear, and the outer surface of the rotating ring is provided with a second gear, and the first gear and the second gear are connected in a transmission manner.

[0043] Furthermore, the rotating assembly also includes a driven shaft, the outer surface of which is provided with a third gear, which is connected to a second gear in a transmission manner; the driven shaft is connected to the angle sensor.

[0044] As described above, the rotating ring also drives the driven shaft to rotate, so that the angle sensor can determine the rotation angle of the standard polarizer based on the transmission ratio between the rotating ring and the driven shaft, and send it to the processor.

[0045] Furthermore, there are two polarizing components and two photoelectric sensor components, with each polarizing component corresponding to one of the two standard polarizers, and each photoelectric sensor component corresponding to one of the two polarizing components.

[0046] As described above, both lenses of the eyeglasses to be tested can be tested simultaneously.

[0047] The present invention also proposes a polarization axis detection method based on the polarization axis detection device described above, comprising:

[0048] By controlling the rotating component, the standard polarizer is rotated. During the rotation, the rotation angle and the voltage signals output by the first and second photoelectric sensors are acquired in real time. The correlation between the rotation angle and the first and second voltage values ​​is obtained. Based on the voltage signals output by the first and second photoelectric sensors, the highest and lowest voltage values ​​are calibrated. The rotation angle is the angle between the polarization direction of the standard polarizer and the polarization direction of the second polarizer.

[0049] The standard polarizer is replaced with the lens under test, the ideal polarization direction of the lens under test is the same as the polarization direction of the second polarizer, and the voltage signals output by the first photoelectric sensor and the second photoelectric sensor are obtained to obtain the third voltage value and the fourth voltage value, which are used as the current third voltage value and the current fourth voltage value.

[0050] Based on the correlation between the first voltage value and the rotation angle, the rotation angle corresponding to the current third voltage value is obtained as the current rotation angle, and based on the correlation between the rotation angle and the second voltage value, the second voltage value corresponding to the current rotation angle is obtained;

[0051] Calculate the average of the current fourth voltage value and the corresponding second voltage value as the current average value, and calculate the current ratio value based on the current average value and the current fourth voltage value;

[0052] Determine whether the absolute value of the difference between the current ratio and 1 is less than a preset threshold;

[0053] If so, the current rotation angle will be used as the final polarization axis error angle;

[0054] If not, then the new third voltage value and the new fourth voltage value are calculated based on the current third voltage value, the current fourth voltage value, the current ratio value, the highest voltage value, and the lowest voltage value.

[0055] The new third voltage value and the new fourth voltage value are respectively used as the current third voltage value and the current fourth voltage value. The steps of obtaining the rotation angle corresponding to the current third voltage value based on the correlation between the first voltage value and the rotation angle, and obtaining the second voltage value corresponding to the current rotation angle based on the correlation between the rotation angle and the second voltage value are continued.

[0056] Furthermore, the specific steps of rotating the standard polarizer by controlling the rotating assembly are as follows:

[0057] With the polarization direction of the second polarizer as the 0-degree angle and the counterclockwise direction as the positive direction, the polarization direction of the standard polarizer is rotated from -α to α by controlling the rotating component, where α is a preset angle.

[0058] As can be seen from the above description, since the axis deviation is generally within the preset range, rotation can be performed only within the preset range of the standard axis to improve calibration efficiency.

[0059] Furthermore, α = 45°.

[0060] As described above, the two photoelectric sensors can output a waveform of half a cycle.

[0061] Further, the step of calculating the average of the current fourth voltage value and the corresponding second voltage value as the current average value, and calculating the current proportion value based on the current average value and the current fourth voltage value, specifically involves:

[0062] According to formula A i =(V 4i +V 2i ) / 2 calculates the current average value, where V 4i This is the current fourth voltage value, V 2i The current rotation angle θ i The corresponding second voltage value;

[0063] According to formula k i =A i / V 4i Calculate the current ratio.

[0064] Furthermore, the calculation of the new third voltage value and the new fourth voltage value based on the current third voltage value, the current fourth voltage value, the current ratio value, the highest voltage value, and the lowest voltage value specifically involves:

[0065] According to formula V 3(i+1) =V mid +((V 3i -V mid )×k i V mid =(Vmax +V min ) / 2 to calculate the new third voltage value, where V 3(i+1) For the new third voltage value, V 3i The current third voltage value, k i V is the current scale value. max and V min These are the highest and lowest voltage values, respectively;

[0066] According to formula V 4(i+1) =V mid +((V 4i -V mid )×k i Calculate the new fourth voltage value, where V 4(i+1) For the new fourth voltage value, V 4i This is the current fourth voltage value.

[0067] Example 1

[0068] Please refer to Figure 1-5 Embodiment 1 of the present invention is: a polarization axis detection device, which can be applied to batch detection of the polarization axis error angle of polarized lenses of polarized sunglasses.

[0069] like Figure 1 As shown, it includes a polarizing assembly 1, a photodetector assembly 2, a standard polarizer 3, a rotating assembly 4, a light source 5, and a processor 6; wherein, the photodetector assembly 2 includes a first photodetector 21 and a second photodetector 22, and the polarizing assembly 1 includes a first polarizer 11 and a second polarizer 12, as shown. Figure 2 As shown, the angle between the polarization directions of the first polarizer 11 and the second polarizer 12 is 45°.

[0070] like Figure 1 As shown, a standard polarizer 3 is mounted on a rotating assembly 4, which rotates the standard polarizer 3. A light source 5 is located on one side of the standard polarizer 3 and illuminates it uniformly. A polarizing assembly 1 is located on the other side of the standard polarizer 3. The two polarizers in the polarizing assembly 1 are located on the same plane, which is parallel to the plane containing the standard polarizer 3. The projection of the standard polarizer 3 onto this plane covers the first polarizer 11 and the second polarizer 12, so that the light emitted from the light source 5 can illuminate the first polarizer 11 and the second polarizer 12 after passing through the standard polarizer 3. A first photoelectric sensor 21 is located on the side of the first polarizer 11 away from the light source 5, and a second photoelectric sensor 22 is located on the side of the second polarizer 12 away from the light source 5. The processor 6 is communicatively connected to both the first photoelectric sensor 21 and the second photoelectric sensor 22.

[0071] like Figure 3As shown, in this embodiment, it also includes a frame 7, and the light source 5, the rotating assembly 4, and the standard polarizer 3, polarizing assembly 1, and photoelectric sensor assembly 2 are arranged on the frame 7 from top to bottom. Of course, in other embodiments, the above structure can also be arranged on the frame from bottom to top.

[0072] Specifically, in this embodiment, the light source 5 is disposed on the top of the frame 7, and the light emission direction of the light source 5 is downward. The frame 7 is provided with a first placement platform 71 and a second placement platform 72 in parallel, the first placement platform 71 is located below the light source 5, and the second placement platform 72 is located below the first placement platform 71. The rotating component 4 is disposed on the first placement platform 71, and the polarizing component 1 is disposed on the second placement platform 72.

[0073] In this embodiment, the detection device also includes an angle sensor 8, which is also disposed on the first placement stage 71; the rotating assembly 4 includes a rotating motor 41, a driving shaft 42 and a rotating ring 43, and also includes a driven shaft 44. The outer surface of the driving shaft 42 is provided with a first gear 45, the outer surface of the rotating ring 43 is provided with a second gear 46, and the outer surface of the driven shaft 44 is provided with a third gear 47.

[0074] The first placement platform 71 has a hollow structure, that is, the first placement platform 71 has an inner cavity 711. The first placement platform 71 also has a first through groove 712, a second through groove 713 and a third through groove 714 communicating with the inner cavity. The first through groove 712 is adapted to the active rotating shaft 42, the second through groove 713 is adapted to the rotating ring 43, and the third through groove 714 is adapted to the driven rotating shaft 44.

[0075] Combination Figure 4 As shown, the output shaft of the rotary motor 41 is connected to the active rotating shaft 42, which is located in the first through slot 712. The first gear 45 on the outer surface of the active rotating shaft 42 is located in the inner cavity 711 of the first placement stage 71. The standard polarizer 3 is disposed in the rotating ring 43, which is located in the second through slot 713. The second gear 46 on the outer surface of the rotating ring 43 is located in the inner cavity 711 of the first placement stage 71, and the second gear 46 is connected to the first gear 45 in a driving connection. The driven rotating shaft 44 is located in the third through slot 714. The third gear 47 on the outer surface of the driven rotating shaft 44 is located in the inner cavity 711 of the first placement stage 71, and is connected to the second gear 46 in a driving connection. The driven rotating shaft 44 is connected to the angle sensor 8, and the angle sensor 8 is connected to the processor 6 in a communication connection (the connection relationship is not shown in the figure).

[0076] When the output shaft of the rotary motor rotates, it synchronously drives the active rotating shaft to rotate, which in turn drives the rotating ring to rotate, thereby causing the standard polarizer in the rotating ring to rotate. The rotating ring also drives the driven rotating shaft to rotate, so that the angle sensor can determine the rotation angle of the standard polarizer according to the transmission ratio between the rotating ring and the driven rotating shaft, and send it to the processor.

[0077] In an optional embodiment, a bracket (not shown in the figure) may also be provided on the first placement platform, and the rotary motor is mounted on the bracket to avoid the weight of the rotary motor itself affecting the rotation of its output shaft.

[0078] like Figure 3 As shown, the second placement stage 72 is provided with a polarizing component placement slot 721, and the first polarizer 11 and the second polarizer 12 are disposed in the polarizing component placement slot 721.

[0079] The first photoelectric sensor 21 is disposed on the side of the first polarizer 11 away from the light source 5, and the second photoelectric sensor 22 is disposed on the side of the second polarizer 12 away from the light source 5. Preferably, the first photoelectric sensor 21 is disposed at the center of the first polarizer 11, and the second photoelectric sensor 22 is disposed at the center of the second polarizer 12. The processor 6 is located at the bottom of the frame 7 and is communicatively connected to the first photoelectric sensor 21 and the second photoelectric sensor 22.

[0080] The first photoelectric sensor 21 can collect the light signal after the light source 5 passes through the standard polarizer 3 and the first polarizer 11 in sequence. The second photoelectric sensor 22 can collect the light signal after the light source 5 passes through the standard polarizer 3 and the second polarizer 12 in sequence. After the two photoelectric sensors collect the light signal, they will convert the light signal into an electrical signal and then output it to the processor 6. The processor 6 will analyze and process the signal in conjunction with the rotation angle sent by the angle sensor.

[0081] During the rotation of the standard polarizer, since the two polarizers in the polarizing assembly are fixed, the angle between the polarization direction of the standard polarizer and the two polarizers in the polarizing assembly is constantly changing. During this process, the light source continuously illuminates the image, causing the voltage signals collected by the two photodetectors to change periodically. Furthermore, since the angle between the polarization directions of the two polarizers in the polarizing assembly is 45°, the signal waveforms output by the two photodetectors can be consistent with the sine function waveform and the cosine function waveform, respectively.

[0082] By acquiring the output values ​​of the angle sensor and the two photoelectric sensors at the same moment, the rotation angle and its corresponding two voltage values ​​at that moment can be obtained. By acquiring the output values ​​of the angle sensor, the first photoelectric sensor, and the second photoelectric sensor in real time, a reference table can be calibrated. This reference table records the correlation between the rotation angle and the first voltage value (the voltage value output by the first photoelectric sensor) and the second voltage value (the voltage value output by the second photoelectric sensor).

[0083] When testing the eyeglasses, remove the standard polarizer, place the eyeglasses under test on the first placement stage, and align the position of the lens under test with the second through slot or rotating ring so that the light emitted from the light source can pass through the lens under test and the two polarizers in the polarizing assembly in sequence. Then, read the voltage values ​​output by the first and second photoelectric sensors, and analyze them in conjunction with the aforementioned comparison table to determine the axis deviation of the lens under test.

[0084] Furthermore, such as Figure 5 As shown, to facilitate simultaneous testing of both lenses of the eyeglasses under test, the first placement stage 71 is also provided with a fourth through slot 715. The distance between the fourth through slot 715 and the second through slot 713 is adapted to the distance between the two lenses of the eyeglasses under test, and the light source 5 can evenly illuminate the second through slot 713 and the fourth through slot 715. Simultaneously, there are two polarizing components 1 and two photoelectric sensor components 2. One polarizing component 1 is positioned corresponding to the position of the second through slot 713, and the other polarizing component 1 is positioned corresponding to the position of the fourth through slot 715. The two photoelectric sensor components 2 correspond one-to-one with the two polarizing components 1, and the two photoelectric sensor components 2 are communicatively connected to the processor 6. The second placement stage 72 is provided with two polarizing component placement slots 721, and the two polarizing components 1 are respectively disposed in the two polarizing component placement slots 721.

[0085] Furthermore, a clamping assembly (not shown in the figure) is also provided on the first placement stage, so that the glasses to be tested can be fixed on the first placement stage during testing.

[0086] In this embodiment, the light emitted by the light source passes sequentially through a standard polarizer and a polarizing assembly. By rotating the standard polarizer, the angle between its polarization direction and the polarization directions of the two polarizers in the polarizing assembly changes. During this process, the voltage signals collected by the two photodetectors also change periodically. By real-time acquisition of the rotation angle of the standard polarizer's polarization direction relative to the polarization direction of the second polarizer and the voltage signals output by the two photodetectors, two voltage values ​​corresponding to each rotation angle can be calibrated and recorded as a reference table. When testing the glasses to be tested, the standard polarizer is removed, and the glasses to be tested are placed on the first placement stage, aligning the lens to be tested with the second and fourth slots on the first placement stage. This allows the light emitted by the light source to pass sequentially through the lens to be tested and the polarizing assembly. The voltage values ​​output by the photodetector assembly are then read and analyzed based on the reference table to determine the axis deviation of the lens to be tested.

[0087] Example 2

[0088] Please refer to Figure 6-9 This embodiment describes the polarization axis detection method of the polarization axis detection device in Embodiment 1. Before performing the detection, the light source is turned on.

[0089] like Figure 6 As shown, it includes the following steps:

[0090] S1: By controlling the rotating assembly, the standard polarizer is rotated. During the rotation, the rotation angle and the voltage signals output by the first and second photoelectric sensors are acquired in real time. The correlation between the rotation angle and the first and second voltage values ​​is obtained. Based on the voltage signals output by the first and second photoelectric sensors, the highest and lowest voltage values ​​are calibrated. The rotation angle is the angle between the polarization direction of the standard polarizer and the polarization direction of the second polarizer.

[0091] Because the standard polarizer rotates while the first and second polarizers remain stationary, the signal waveforms output by the first and second photoelectric sensors resemble a sine (or cosine) function with a period of 180°.

[0092] Therefore, in one embodiment, the standard polarizer can be rotated at least 180° so that the two photosensitive sensors can output a waveform of at least one cycle. At this point, based on the waveform of one cycle, the highest and lowest voltage values, i.e., the maximum and minimum values ​​of the first and second voltage values, can be calibrated.

[0093] However, in this embodiment, considering that the axis deviation is generally within a preset range, rotation can be performed only within the preset range of the standard axis. Specifically, in this embodiment, with the polarization direction of the second polarizer as the 0-degree angle direction and the counterclockwise direction as the positive direction, the polarization direction of the standard polarizer is rotated from -α to α by controlling the rotation component, where α is a preset angle. Here, α = 45°, meaning the polarization direction of the standard polarizer rotates from -45° to 45°, allowing the two photodetectors to output waveforms for at least half a cycle. At this time, since the angle between the polarization directions of the first and second polarizers is 45°, the highest and lowest voltage values ​​can be calibrated based on the half-cycle voltage signal output by the second photodetector (the highest voltage value is the voltage value output by the second photodetector when the standard polarizer rotates to 45°, and the lowest voltage value is the voltage value output by the second photodetector when the standard polarizer rotates to -45°).

[0094] When the polarization direction of the standard polarizer cannot be determined, the standard polarizer can be rotated first, and the highest voltage value can be calibrated according to the voltage signal output by the second photodetector. The rotation angle corresponding to the highest voltage value is taken as the 0-degree angle. Then, starting from the 0-degree angle, the standard polarizer is rotated counterclockwise by 45°, and the voltage signals output by the two photodetectors are collected in real time. Then, it is rotated back to the 0-degree angle, and the standard polarizer is rotated clockwise by 45° from the 0-degree angle, and the voltage signals output by the two photodetectors are collected in real time.

[0095] Furthermore, during the rotation of the standard polarizer, voltage signals from the two photoelectric sensors are collected every time the preset rotation degree is reached. For example, every 5° rotation, the voltage signals from the first and second photoelectric sensors are collected to obtain the first and second voltage values ​​corresponding to the current rotation angle. A lookup table is then generated. Figure 7 As shown in the table, the signal waveform functions corresponding to the first and second photoelectric sensors can be fitted respectively, as follows: Figure 8 As shown, V1 represents the voltage signal output by the first photoelectric sensor, and V2 represents the voltage signal output by the second photoelectric sensor. It can be seen that the waveform of V1 is consistent with the waveform of the sine function, and the waveform of V2 is consistent with the waveform of the cosine function.

[0096] The relationship between the rotation angle and the first voltage value is used for subsequent table lookup, and the relationship between the rotation angle and the second voltage value is used for subsequent correction.

[0097] S2: Replace the standard polarizer with the lens under test, and acquire the voltage signals output by the first and second photoelectric sensors to obtain the third and fourth voltage values, which are used as the current third and fourth voltage values. The ideal polarization direction of the lens under test is the same as the polarization direction of the second polarizer.

[0098] The standard polarizer is removed from the rotating assembly, and the eyeglasses under test are placed on the first placement stage. The two lenses of the eyeglasses are aligned with the second and fourth slots on the first placement stage, respectively, allowing the light source to pass through the two lenses and illuminate the two polarizing assemblies located on the second placement stage. Furthermore, when placing the eyeglasses, the ideal polarization direction of the lenses must be the same as the polarization direction of the second polarizer.

[0099] This embodiment uses the detection of the axis deviation of one of the lenses under test in the eyeglasses as an example for illustration. The detection method for the other lens under test is the same.

[0100] Assuming the lens under test is rotated, both the first and second photoelectric sensors will output waveforms resembling a sine (or cosine) function with a period of 180°. However, due to differences in the thickness, material, refractive index, and other parameters of the lens under test compared to a standard polarizer, or due to light source loss during the detection process, the signal waveforms output by the two photoelectric sensors may fluctuate. Figure 9 As shown, V1 and V2 represent waveforms measured by rotating the standard polarizer, and V3 and V4 represent waveforms measured by rotating the lens under test. It can be seen that for waveforms V1 and V3 (both output by the first photosensitive sensor), when the voltage values ​​are the same, the corresponding rotation angles are not necessarily the same; similarly, for waveforms V2 and V4 (both output by the second photosensitive sensor), when the voltage values ​​are the same, the corresponding rotation angles are not necessarily the same. In other words, if a direct lookup and matching is performed based on the lookup table obtained in step S1 using the current third and fourth voltage values, the matched axis deviation may be inaccurate.

[0101] Therefore, this embodiment further achieves automatic correction of shaft position deviation through the following steps.

[0102] S3: Based on the relationship between the first voltage value and the rotation angle, obtain the rotation angle corresponding to the current third voltage value as the current rotation angle, and based on the relationship between the rotation angle and the second voltage value, obtain the second voltage value corresponding to the current rotation angle.

[0103] The current third voltage value V 3i Substitute the first voltage value into the lookup table and find the corresponding rotation angle θ. i , or substitute Figure 9The corresponding rotation angle θ is calculated from the waveform function corresponding to V1. i Then, with the matched rotation angle θ i Find the matching second voltage value V in the lookup table. 2i , or substitute Figure 9 The second voltage value is obtained by calculating the waveform function corresponding to V2.

[0104] Where i represents the iteration number, and the initial value is 0. When i = 0, V 3i and V 4i These are the third and fourth voltage values ​​obtained the first time after replacing the standard polarizer with the lens under test.

[0105] S4: Calculate the average of the current fourth voltage value and the corresponding second voltage value as the current average value, and calculate the current ratio value based on the current average value and the current fourth voltage value.

[0106] Specifically, according to formula A i =(V 4i +V 2i ) / 2 calculates the current average value, where V 4i This is the current fourth voltage value, V 2i The current rotation angle θ i The corresponding second voltage value; then according to formula k i =A i / V 4i Calculate the current ratio.

[0107] S5: Determine whether the absolute value of the difference between the current ratio value and 1 is less than a preset threshold, i.e., determine |k i If -1|<ε is true, proceed to step S6; otherwise, proceed to step S7.

[0108] S6: Set the current rotation angle θ i As the final polarization axis error angle.

[0109] S7: Based on the current third voltage value, the current fourth voltage value, the current proportional value, the highest voltage value, and the lowest voltage value, calculate the new third voltage value and the new fourth voltage value; that is, the new third voltage value V. 3(i+1) =V mid +((V 3i -V mid )×k i The new fourth voltage value V 4(i+1) =V mid +((V 4i -V mid )×k i V mid =(Vmax +V min ) / 2, where V max and V min These are the highest and lowest voltage values ​​obtained in step S1, respectively. In this embodiment, V max =3V, V min =1V, then V mid =2V. Then, the new third voltage value and the new fourth voltage value are used as the current third voltage value and the current fourth voltage value, respectively, that is, let i = i + 1, and continue to execute step S3.

[0110] The ratio calculated in step S4 characterizes the closeness between the current fourth voltage value and the second voltage value corresponding to the current third voltage value. The closer the ratio is to 1, the closer the second voltage value corresponding to the current third voltage value is to the current fourth voltage value. In other words, the rotation angle obtained from the table is closer to the actual rotation angle. Therefore, when the absolute value of the difference between the ratio and 1 is less than a preset threshold, the iteration is considered complete, and the current rotation angle is taken as the final axis deviation. When the ratio is not yet close to 1, the iteration is considered incomplete. This is determined by observation. Figure 9 It can be seen that waveforms V3 and V4, compared to waveforms V1 and V2, both oscillate towards the center. This means the amplitude of the waveform functions corresponding to V3 and V4 is smaller than the amplitude of the waveform functions corresponding to V1 and V2. Therefore, by calculating the average value V of the highest and lowest voltage values... mid Then subtract the average value V from the third and fourth voltage values ​​respectively. mid Then multiply by the ratio, and finally add the average value V. mid This is done to update the third and fourth voltage values, making them approach the midpoint between the current voltage value and the voltage value obtained from the lookup table, thereby getting closer to the voltage value corresponding to the actual rotation angle.

[0111] In this embodiment, step S1 can be performed only once for different batches of glasses to be tested. That is, the reference table obtained in step S1 can be applied to the subsequent testing of different batches of glasses to be tested. Therefore, in practical applications, the reference table can be calibrated first and stored in the processor in advance. When conducting subsequent testing, in addition to removing the standard polarizer, the rotating component and angle sensor can also be removed, thereby simplifying the structural complexity of the testing device during application.

[0112] In summary, the polarization axis detection device and method provided by the present invention can detect the axis deviation of polarizing lenses more quickly and accurately, and can be carried out in batches, effectively identifying and eliminating defective products.

[0113] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for detecting a polarizing axis position based on a polarizing axis position detection device, characterized by, The polarized axis position detection device comprises a polarized component, a photoelectric sensor component, a standard polaroid, a rotating component, a light source and a processor, the polarized component comprises a first polaroid and a second polaroid, the included angle between the polarization directions of the first polaroid and the second polaroid is 45°, the photoelectric sensor component comprises a first photoelectric sensor and a second photoelectric sensor; The standard polaroid is arranged on the rotating component, the rotating component is used to drive the standard polaroid to rotate, the light source is located on one side of the standard polaroid and uniformly irradiates the standard polaroid, the first polaroid and the second polaroid are located on the other side of the standard polaroid, and the first polaroid and the second polaroid are located on the same plane, the projection of the standard polaroid on the same plane covers the first polaroid and the second polaroid, the first photoelectric sensor is arranged on the side of the first polaroid away from the light source, the second photoelectric sensor is arranged on the side of the second polaroid away from the light source, and the processor is in communication connection with the first photoelectric sensor and the second photoelectric sensor respectively; An angle sensor is further included, the angle sensor is connected with the rotating component, and the angle sensor is in communication connection with the processor; The method comprises: By controlling the rotating component, the standard polaroid is rotated, the rotation angle and the voltage signals output by the first photoelectric sensor and the second photoelectric sensor are acquired in real time during the rotation process, the correlation between the rotation angle and the first voltage value and the second voltage value is obtained, the highest voltage value and the lowest voltage value are calibrated according to the voltage signals output by the first photoelectric sensor and the second photoelectric sensor, and the rotation angle is the included angle between the polarization direction of the standard polaroid and the polarization direction of the second polaroid; The standard polaroid is replaced by a to-be-tested lens, the ideal polarization direction of the to-be-tested lens is the same as the polarization direction of the second polaroid, and the voltage signals output by the first photoelectric sensor and the second photoelectric sensor are acquired to obtain a third voltage value and a fourth voltage value as a current third voltage value and a current fourth voltage value; According to the correlation between the first voltage value and the rotation angle, the rotation angle corresponding to the current third voltage value is acquired as a current rotation angle, and according to the correlation between the rotation angle and the second voltage value, the second voltage value corresponding to the current rotation angle is acquired; The average value of the current fourth voltage value and the corresponding second voltage value is calculated as a current average value, and the current ratio value is calculated according to the current average value and the current fourth voltage value; It is judged whether the absolute value of the difference between the current ratio value and 1 is less than a preset threshold value; If yes, the current rotation angle is taken as the final polarized axis position error angle; If no, new third voltage value and new fourth voltage value are calculated according to the current third voltage value, the current fourth voltage value, the current ratio value, the highest voltage value and the lowest voltage value. The new third voltage value and the new fourth voltage value are taken as a current third voltage value and a current fourth voltage value respectively, and the step of obtaining a rotation angle corresponding to the current third voltage value as a current rotation angle according to the association between the first voltage value and the rotation angle, and obtaining a second voltage value corresponding to the current rotation angle according to the association between the rotation angle and the second voltage value is continuously performed.

2. The polarizing axis position detection method according to claim 1, wherein The rotation assembly comprises a rotating motor, a driving shaft and a rotating ring, the standard polaroid is arranged in the rotating ring, the rotating ring is in transmission connection with the driving shaft, and the driving shaft is connected with the rotating motor.

3. The polarizing axis position detection method according to claim 2, wherein The outer surface of the driving shaft is provided with a first gear, the outer surface of the rotating ring is provided with a second gear, and the first gear and the second gear are in transmission connection.

4. The polarizing axis position detection method according to claim 3, wherein The rotation assembly further comprises a driven shaft, the outer surface of the driven shaft is provided with a third gear, the third gear and the second gear are in transmission connection, and the driven shaft is connected with the angle sensor.

5. The polarizing axis position detection method according to claim 1, wherein The number of the polaroid assembly and the photoelectric sensor assembly is two, two polaroid assemblies are one-to-one corresponding to two standard polaroids, and two photoelectric sensor assemblies are one-to-one corresponding to two polaroid assemblies.

6. The polarizing axis position detection method according to claim 1, wherein The specific process of rotating the standard polaroid by controlling the rotation assembly is as follows: Taking the polarization direction of the second polaroid as the 0-degree angle direction and the counterclockwise direction as the positive direction, the polarization direction of the standard polaroid is rotated from -α to α by controlling the rotation assembly, and α is a preset angle.

7. The polarizing axis position detection method according to claim 6, wherein α=45°。 8. The polarizing axis position detection method according to claim 1, wherein The specific process of calculating the average value of the current fourth voltage value and the corresponding second voltage value as a current average value, and calculating a current proportion value according to the current average value and the current fourth voltage value is as follows: According to formula A i = (V 4i + V 2i ) / 2, wherein V 4i is the current fourth voltage value, V 2i is the current corresponding second voltage value, and θ i is the current rotation angle. According to the formula k i = A i / V 4i The current scale value is calculated.

9. The polarizing axis position detection method according to claim 1, wherein The specific process of calculating the new third voltage value and the new fourth voltage value according to the current third voltage value, the current fourth voltage value, the current proportion value, the highest voltage value and the lowest voltage value is as follows: According to the formula V 3（i+1） = V mid + ((V 3i - V mid ) x k i ), V mid = (V max + V min ) / 2, wherein V 3（i+1） is a new third voltage value, V 3i is a current third voltage value, k i is a current ratio value, V max and V min are the highest voltage value and the lowest voltage value, respectively, and V mid is an average of the highest voltage value and the lowest voltage value. According to the formula V 4（i+1） = V mid + ((V 4i - V mid ) x k i ) where V 4‍（i+1） is the new fourth voltage value and V 4i is the current fourth voltage value.

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