Device for measuring parallel half angle of light source and method for measuring parallel half angle of light source

Abstract

The present invention discloses a device and method for measuring the parallel half-angle of a light source, wherein the measuring device comprises a photometric tube, an imaging cavity is arranged in the photometric tube, the imaging cavity has an incident end and an imaging end opposite to each other, the photometric tube is also provided with an incident hole, the incident hole connects the incident end and the outer side of the photometric tube, the light beam emitted by the light source can enter the imaging cavity through the incident hole, and a light spot is formed on the end face of the imaging end by using the pinhole imaging principle, and the light spot is used to characterize the parallel half-angle of the light source. The technical solution of the present invention can make the measuring device for measuring the parallel half-angle of a collimated light source simple in structure and easy to implement.

Description

Technical Field

[0001] The invention relates to the technical field of measuring equipment, and in particular to a device and method for measuring the parallel half-angle of a light source. Background Art

[0002] With the development of precision graphic transfer processing technology, the accuracy of transfer circuits and graphics has been greatly improved, which in turn has greatly improved the performance of electronic products. As the market places higher demands on the performance of electronic products, it in turn promotes the further development of precision graphic transfer processing technology.

[0003] At present, precision graphic transfer is gradually moving from surface light sources to small-angle collimated light sources, and the requirements for the parallel half-angle and light deviation angle of the collimated light source are becoming increasingly stringent. Therefore, there is an urgent need to provide a simple and easy-to-implement measurement device to measure the parallel half-angle of the collimated light source. Summary of the invention

[0004] The main purpose of the present invention is to provide a device for measuring the parallel half-angle of a light source, aiming to make the device for measuring the parallel half-angle of a collimated light source simple in structure and easy to implement.

[0005] To achieve the above-mentioned purpose, the measuring device of the parallel half-angle of a light source proposed in the present invention comprises a photometric tube, wherein an imaging cavity is arranged in the photometric tube, wherein the imaging cavity has an incident end and an imaging end relative to each other, and the photometric tube is further provided with an incident hole, wherein the incident hole connects the incident end and the outer side of the photometric tube, and a light beam emitted by the light source can enter the imaging cavity through the incident hole, and a light spot is formed on the end face of the imaging end by utilizing the pinhole imaging principle, and the light spot is used to characterize the parallel half-angle of the light source.

[0006] Optionally, the minimum diameter of the incident hole ranges from 0.8 mm to 1.2 mm.

[0007] Optionally, a hole wall surface of the incident hole is configured as a frustum surface, and the incident hole is gradually expanded toward a direction close to the imaging end.

[0008] Optionally, a plurality of concentric annular scale lines with different radii are provided on the end surface of the imaging end.

[0009] Optionally, the side wall of the light measuring tube is further provided with an observation window connected to the imaging cavity, and the observation window is arranged adjacent to the imaging end.

[0010] Optionally, a photosensitive device is provided on the end surface of the imaging end, and the photosensitive device can at least detect the size of the light spot.

[0011] Optionally, the photosensitive device includes a CCD detector, the end wall of the imaging cavity is provided with a mounting hole, the lens of the CCD detector is at least partially exposed in the mounting hole, and the end face of the imaging end is at least partially formed on the photosensitive surface of the lens of the CCD detector.

[0012] Optionally, the photosensitive device includes a plurality of position-sensitive detectors, and the plurality of position-sensitive detectors are distributed on the end surface of the imaging end at intervals along the radial direction of the light spot.

[0013] Optionally, the device for measuring the parallel half-angle of the light source further comprises a camera disposed in the imaging cavity, and the camera is used to capture an image of the area where the light spot is located.

[0014] Optionally, the light measuring tube includes a tube body with an opening at one end, and a first end cover covering the opening of the tube body, the incident hole is arranged in the middle of the first end cover, and the first end cover is movably connected to the tube body to adjust the axial inclination and / or position of the incident hole.

[0015] Optionally, the light measuring tube also includes a plurality of top screws, which are distributed at intervals along the circumference of the incident hole, and the side wall of the first end cover is provided with a threaded hole corresponding to the top screw, the top screw is threadedly connected to the threaded hole, and one end of the top screw passing through the threaded hole abuts against the outer circumferential surface of the tube body.

[0016] The present invention further provides a method for measuring the parallel half-angle of a light source, which is applied to the aforementioned device for measuring the parallel half-angle of a light source. The method for measuring the parallel half-angle of a light source comprises the following steps:

[0017] Acquire the original image of the light spot on the imaging end and generate an initial light spot;

[0018] Performing edge detection and contour extraction on the initial light spot to obtain a final light spot;

[0019] Calculate and obtain the radius r of the final light spot;

[0020] Substitute the radius r of the final light spot and the height L of the imaging cavity into the parallel half-angle calculation formula, and calculate the parallel half-angle β of the light source, wherein the parallel half-angle calculation formula is Tan β=r / L.

[0021] In the technical solution of the present invention, the light beam of the light source is converted into a light spot on the imaging end by using the pinhole imaging principle, and the light spot size is used to characterize the parallel half-angle size of the collimated light source. The structure of the measuring device of the parallel half-angle of the light source is simple and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0023] Figure 1 It is a structural schematic diagram of an embodiment of a device for measuring the parallel half-angle of a light source of the present invention;

[0024] Figure 2 It is a schematic diagram of the pinhole imaging principle of the device for measuring the parallel half-angle of the light source of the present invention;

[0025] Figure 3 It is a structural schematic diagram of another embodiment of the device for measuring the parallel half-angle of a light source of the present invention;

[0026] Figure 4 for Figure 3 A front view of a measuring device for the parallel half angle of the light source shown;

[0027] Figure 5 for Figure 4 Sectional view at AA in the middle;

[0028] Figure 6 A schematic diagram of the hardware operating environment of the method for measuring the parallel half-angle of a light source of the present invention;

[0029] Figure 7 Schematic diagram of the steps of an embodiment of a method for measuring the parallel half-angle of a light source of the present invention.

[0030] Description of Figure Numbers:

[0031] Label name Label name 101 beam 112 Imaging end 102 Measuring device 12 Entrance hole 10 Light meter tube 13 Ring scale line 10a Barrel body 14 Observation Window 10b First end cap 15 Mounting holes 10c Second end cap 20 CCD Detector 11 Imaging cavity 21 Lens sensitive surface 111 Incident end 30 Top Screw

[0032] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0035] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0037] With the development of precision graphic transfer processing technology, such as precision pattern UV transfer technology, the accuracy of transfer circuits and graphics has been greatly improved, which in turn has greatly improved the performance of electronic products. As the market places higher demands on the performance of electronic products, it in turn promotes the further development of precision graphic transfer processing technology.

[0038] At present, precision graphic transfer is gradually moving from surface light sources to small-angle collimated light sources, and the requirements for the parallel half-angle and light deviation angle of the collimated light source are becoming increasingly stringent. Therefore, there is an urgent need to provide a simple and easy-to-implement measurement device to measure the parallel half-angle of the collimated light source.

[0039] In view of this, the present invention proposes a measuring device for the parallel half-angle of a light source (hereinafter referred to as the measuring device), please refer to Figures 1 to 5In some embodiments of the present invention, the measuring device 102 includes a photometric tube 10, wherein an imaging cavity 11 is provided in the photometric tube 10, wherein the imaging cavity 11 has an incident end 111 and an imaging end 112 opposite to each other, and the photometric tube 10 is further provided with an incident hole 12, wherein the incident hole 12 connects the incident end 111 and the outer side of the photometric tube 10, and a light beam 101 emitted by a light source can enter the imaging cavity 11 through the incident hole 12, and a light spot is formed on the end face of the imaging end 112 by utilizing the pinhole imaging principle, and the light spot is used to characterize the parallel half-angle of the light source.

[0040] For details, please refer to Figure 2 , Figure 2 The schematic diagram of the principle of pinhole imaging of the measuring device 102 of the present invention is shown in the figure. The light beam 101 emitted by the collimated light source passes through the incident hole 12 and forms a conical light beam 101 in the imaging cavity 11. After the conical light beam 101 forms a light spot on the end face of the imaging end 112, the imaging cavity height L and the radius r of the light spot are both known conditions, and the cone half angle α of the conical light beam 101 can be calculated. Specifically, Tanα=r / L. According to the principle of pinhole imaging, the parallel half angle β of the light source is equal to the cone half angle α. It can be understood that since the imaging cavity height L, the light spot radius r and the parallel half angle β of the light source satisfy the formula Tanβ=r / L, and the imaging cavity height L remains unchanged, the light spot size can be used to characterize the parallel half angle size of the light source.

[0041] In the technical solution of the present invention, the light beam 101 of the light source is converted into a light spot on the imaging end 112 using the pinhole imaging principle, and the light spot size is used to characterize the parallel half-angle size of the collimated light source. The structure of the measuring device 102 is simple and easy to implement.

[0042] In some embodiments, optionally, the minimum diameter of the incident hole 12 is in the range of 0.8 mm to 1.2 mm, for example, 1 mm or 1.1 mm. It can be understood that if the minimum diameter of the incident hole 12 is too large, the pinhole imaging effect is not good. If the minimum diameter of the incident hole 12 is too large, the incident hole 12 is difficult to process or the hole wall surface of the incident hole 12 is poor.

[0043] Please refer to Figure 5In some embodiments, optionally, the hole wall surface of the incident hole 12 is configured as a frustum surface, and the incident hole 12 is gradually expanded in the direction close to the imaging end 112, that is, the minimum diameter of the incident hole 12 is located at the end of the incident hole 12 away from the imaging cavity 11. In this way, it is convenient to process and shape the incident hole 12, and it is helpful to avoid the problems of poor processing such as burrs and pits on the hole wall surface of the incident hole 12, and it is also beneficial to the propagation of the light beam 101 in the incident hole 12. On the other hand, the minimum diameter of the incident hole 12 is located at the end of the incident hole 12 away from the imaging cavity 11, and the risk of dust accumulation in the incident hole 12 can be reduced. Of course, in other embodiments, the hole wall surface of the incident hole 12 can also be configured as a frustum surface, and the incident hole 12 is gradually expanded in the direction away from the imaging end 112, that is, the minimum diameter of the incident hole 12 is located at the end of the incident hole 12 close to the imaging cavity 11. In other embodiments, the wall surface of the incident hole 12 may also be provided in the form of a cylindrical surface or other free-form surfaces.

[0044] There are many ways to characterize the parallel half-angle of a light source using a spot, for example, see Figure 1 In some embodiments, a plurality of concentric annular scale lines 13 with different radii are provided on the end surface of the imaging end 112. In this way, the corresponding parallel half-angle is directly marked by a plurality of concentric annular scale lines 13. For example, 30 annular scale lines 13 with uniformly increasing radii are provided, and each annular scale line 13 represents a 0.5° parallel half-angle. The larger the radius of the annular scale line 13, the larger the parallel half-angle corresponding to the spot size. By observing how many annular scale lines 13 are covered by the light spot, the size of the parallel half-angle corresponding to the spot size can be known. For example, when the light spot covers 3 annular scale lines 13, the corresponding parallel half-angle is 1.5°.

[0045] It should be noted that the ring shape includes a closed ring shape and a non-closed ring shape. A closed ring shape means that the scale lines are continuously connected without gaps, and a non-closed ring shape means that the scale lines are disconnected at one or more positions to form gaps, but the whole shape is still ring-shaped.

[0046] Please refer to Figure 1 , Figures 3 to 5 In some embodiments, optionally, the side wall of the photometric tube 10 is further provided with an observation window 14 connected to the imaging cavity 11, and the observation window 14 is arranged adjacent to the imaging end 112. In this way, the observation window 14 can facilitate the user to directly observe the coverage of the light spot on the annular scale line 13, so as to manually observe the size of the light spot and read the corresponding light source parallel half angle. Of course, in other embodiments, the observation window 14 may not be provided, and the light spot situation may be indirectly observed by taking an image with a camera, for example, a camera is provided in the imaging cavity 11, and the camera is used to take an image of the area where the light spot is located.

[0047] Optionally, the measuring device 102 further comprises a window cover (not shown in the drawings) that movably covers the observation window 14, so that when the observation window 14 is not in use, the window cover can be used to temporarily cover the observation window 14 to reduce the risk of dust entering the imaging chamber 11. Specifically, the window cover can be movably mounted on the light measuring tube 10 by means of a pivot connection or a sliding connection, and can also be detachably mounted on the light measuring tube 10 as a whole by means of a buckle or a screw.

[0048] In some embodiments, optionally, a photosensitive device is provided on the end surface of the imaging end 112, and the photosensitive device can at least detect the size of the light spot. On the one hand, the reading accuracy can be improved by the photosensitive device, and the read data does not need to be manually sorted and calculated, thereby improving the efficiency of the measurement work. On the other hand, compared with the method of manually reading the annular scale line 13, this embodiment can reduce labor costs and avoid the risk of eye damage caused by long-term visual light spots (such as light spots formed by ultraviolet light sources).

[0049] Specifically, there are many forms of photosensitive devices, for example, please refer to Figures 3 to 5 In another embodiment, the photosensitive device includes a CCD (charge coupled device) detector, the end wall of the imaging end 112 is provided with a mounting hole 15, the lens of the CCD detector is at least partially exposed in the mounting hole 15, and the end face of the imaging end 112 is at least partially formed on the lens photosensitive surface 21 of the CCD detector. That is, the light spot falls on the lens photosensitive surface 21 of the CCD detector, and the CCD detector directly captures and analyzes the light spot, thereby obtaining the center coordinate value and the diameter of the light spot, and obtaining the parallel half angle and the light deflection angle.

[0050] In this way, the contour accuracy and position accuracy of the light spot can be measured by the CCD detector to the pixel level. Specifically, the diameter of the light spot corresponding to the 0.5° light source parallel half angle can be sensed by dozens of columns of pixels, so that the measurement accuracy of the light source parallel half angle reaches more than 0.1°. That is, this embodiment can significantly improve the measurement accuracy and precision of the parallel half angle, thereby improving the accuracy and yield rate of the precision graphic transfer processing technology.

[0051] In another embodiment, the photosensitive device includes a plurality of position sensitive detectors (PSD, Position Sensitive detector), and the plurality of position sensitive detectors are distributed at intervals along the radial direction of the light spot on the end surface of the imaging end 112. That is, the plurality of position sensitive detectors are distributed on a plurality of concentric circles with different radii. When the light spot covers and excites more position sensitive detectors, it means that the size of the light spot is larger, which means that the light source parallel half angle corresponding to the light spot is larger. In this way, the structure of this embodiment is simple and easy to implement.

[0052] It is worth mentioning that in the embodiment where the end surface of the imaging end 112 is provided with an annular scale line 13, optionally, the end surface of the imaging end 112 is also provided with a position-sensitive detector, and the position-sensitive detector can be arranged in the disconnected area of ​​the non-closed annular scale line 13. In this way, it can support the user to directly visually read the data by the annular scale line 13, and can also use the position-sensitive detector to automatically read the data, thereby improving the use flexibility of the measuring device 102.

[0053] In another embodiment, the measuring device 102 further includes a camera disposed in the imaging cavity 11, and the camera is used to capture an image of the area where the light spot is located. In this way, the size and position of the light spot in the image can be calculated and analyzed by the processor through image analysis of the image collected by the camera, thereby calculating the light source parallel half angle corresponding to the light spot.

[0054] Please refer to Figure 1 , Figures 3 to 5 In some embodiments, optionally, the photometric tube 10 includes a tube body 10a with an opening at one end, and a first end cap 10b covering the opening of the tube body 10a, the incident hole 12 is provided in the middle of the first end cap 10b, and the first end cap 10b is movably connected to the tube body 10a to adjust the axis inclination and / or position of the incident hole 12. In this way, by adjusting the first end cap 10b, the axis inclination and / or position of the incident hole 12 can be adjusted, so that the light spot can fall on the designated area more accurately, and the center of the light spot can coincide or substantially coincide with the center of the designated area, that is, it can coincide or substantially coincide with the center of the annular scale line 13 or the photosensitive device, thereby improving the measurement accuracy. Optionally, the imaging cavity 11 is configured as a cylinder, and the first end cap 10b is movably connected to the tube body 10a to adjust the axis of the incident hole 12 to coincide with the central axis of the imaging cavity 11.

[0055] Specifically, there are many ways to flexibly connect the first end cap 10b to the cylinder body 10a. For example, please refer to Figure 1 , Figure 3 and Figure 4In some embodiments, the photometric tube 10 further includes a plurality of top screws 30 (not shown in the drawings), the plurality of top screws 30 are spaced apart along the circumference of the incident hole 12, the side wall of the first end cap 10b is provided with threaded holes corresponding to the top screws 30, the top screws 30 are threadedly connected to the threaded holes, and one end of the top screws 30 passing through the threaded holes abuts against the outer circumference of the tube body 10a. Thus, by adjusting the length of the top screws 30 (such as machine screws) screwed into the threaded holes, the gap between the inner wall surface of the first end cap 10b and the outer circumference of the tube body 10a at different positions can be adjusted, and by utilizing the lifting degrees of the top screws 30 at different positions, the inclination angle of the first end cap 10b relative to the end surface of the tube body 10a can be adjusted, thereby adjusting the inclination angle of the axis of the incident hole 12. Of course, in other embodiments, the first end cap 10b can also be adjusted in inclination and position relative to the tube body 10a through a ball screw mechanism.

[0056] Please refer to Figure 1 , Figures 3 to 5 In some embodiments, optionally, the other end of the barrel body 10a is also provided with an opening, and the photometric barrel 10 further includes a second end cap 10c that is movable and covers the opening, that is, the second end cap 10c serves as the end wall of the imaging end 112, and the imaging cavity 11 penetrates the barrel body 10a and forms an opening at each end of the barrel body 10a, and the first end cap 10b and the second end cap 10c cover the two openings respectively. In this way, the processing and molding of the photometric barrel 10 is facilitated. Of course, in other embodiments, the second end cap 10c and the barrel body 10a can also be integrally formed.

[0057] The present invention also proposes a method for measuring the parallel half angle of a light source, which is applied to the aforementioned measuring device. Figure 6 , Figure 6The structural diagram of the measuring device of the hardware operating environment involved in the embodiment of the present invention is shown, and the measuring device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Among them, the communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display screen (Display), an input unit such as a keyboard (Keyboard), and the optional user interface 1003 may also include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a wireless fidelity (WIreless-FIdelity, WI-FI) interface). The memory 1005 may be a high-speed random access memory (Random Access Memory, RAM) memory, or a stable non-volatile memory (Non-Volatile Memory, NVM), such as a disk memory. The memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0058] Those skilled in the art will understand that Figure 6 The structure shown in the figure does not constitute a limitation on the measuring device, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0059] like Figure 6 As shown, the memory 1005 as a storage medium may include an operating system, a data storage module, a network communication module, a user interface module, and a measurement device control program. Figure 6 In the measuring device shown, the network interface 1004 is mainly used for data communication with other devices; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the measuring device of the present invention can be set in the measuring device, and the measuring device calls the measuring device control program stored in the memory 1005 through the processor 1001 (i.e., the controller), and executes the steps of the measurement method of the parallel half-angle of the light source provided in the embodiment of the present invention.

[0060] Please refer to Figure 7 In one embodiment of the method for measuring the parallel half-angle of a light source of the present invention, the method for measuring the parallel half-angle of a light source includes steps S110, S120, S130 and S140, which are specifically as follows:

[0061] Step S110: acquiring an original image of the light spot on the imaging end and generating an initial light spot.

[0062] Specifically, there are many ways to obtain the light spot image. For example, in an embodiment in which a CCD detector is provided on the end wall of the imaging end, the light spot is directly imaged on the lens photosensitive surface of the CCD detector. The image position obtained by the CCD detector directly photographing the light spot is straight, and the light spot image has no distortion, so it can be directly applied to the next step.

[0063] For another example, in an embodiment where a camera is provided on the end wall of the incident end, since an incident hole is arranged in the center of the end wall of the incident end, the camera can only be provided on one side of the incident hole, and the camera is tilted toward the light spot for shooting, which causes the light spot image captured by the camera to be distorted. Therefore, the processor needs to correct the light spot image before applying it to the next step.

[0064] In this embodiment, optionally, step S110 includes steps S111, S112, S113 and S114, which are specifically as follows:

[0065] Step S111: performing denoising processing on the original image of the light spot;

[0066] Step S112: performing image enhancement operation on the denoised light spot image by using grayscale transformation processing;

[0067] Step S113: performing image segmentation on the spot image after the image enhancement operation;

[0068] Step S114: performing a binary opening operation of mathematical morphology on the segmented image to obtain an initial light spot.

[0069] Step S120: performing edge detection and contour extraction on the initial light spot to obtain a final light spot.

[0070] In this embodiment, the Canny adaptive edge detection method is first used on the initial light spot to obtain its corresponding edge image; then the wavelet maximum edge detection method is used on the initial light spot to obtain its corresponding edge image; finally, the two edge images are edge-fused by adding weighted factors to obtain the final light spot. In this way, in terms of edge detection, the present invention combines the Canny adaptive edge detection and wavelet maximum edge detection algorithms, which significantly enhances clarity, continuity, and integrity, and also has good robustness.

[0071] Of course, other methods may also be used to implement edge detection and contour extraction of the initial light spot, and this application does not make any specific limitation to this.

[0072] Step S130: Calculate and obtain the radius r of the final light spot.

[0073] In this embodiment, the Canny edge detection algorithm combined with wavelet transform is used to realize edge detection and contour extraction of the light spot, and the image parameters such as the area, perimeter, and equivalent diameter of the final light spot are calculated, and then the radius r of the final light spot is further converted.

[0074] Step S140: Substitute the radius r of the final light spot and the height L of the imaging cavity into the parallel half-angle calculation formula, and calculate the parallel half-angle β of the light source, wherein the parallel half-angle calculation formula is Tan β=r / L.

[0075] For details, please refer to Figure 2 , Figure 2 The schematic diagram of the principle of pinhole imaging of the measuring device 102 of the present invention is shown in FIG. The light beam 101 emitted by the collimated light source passes through the incident hole 12 and forms a conical light beam 101 in the imaging cavity 11. After the conical light beam 101 forms a light spot on the end face of the imaging end 112, the height L of the imaging cavity and the radius r of the light spot are both known conditions, and the cone half angle α of the conical light beam 101 can be calculated. Specifically, Tan α=r / L. According to the principle of pinhole imaging, it can be known that the parallel half angle β of the light source is equal to the cone half angle α. Therefore, the imaging cavity height L, the light spot radius r and the light source parallel half angle β satisfy the formula Tan β=r / L. Therefore, the final light spot radius r and the imaging cavity height L are substituted into the parallel half angle calculation formula, that is, Tan β=r / L, and the parallel half angle β of the light source can be calculated.

[0076] The technical solution of the present invention obtains the spot image through a CCD detector, etc., and automatically calculates the parallel half-angle of the light source based on the spot image. Compared with the method in which the user directly visually reads the annular scale line through the observation window, more accurate parameters such as the spot profile and spot radius can be obtained, thereby not only significantly improving the measurement precision and accuracy of the parallel half-angle, but also reducing labor costs and improving detection efficiency. Specifically, since the contour accuracy and position accuracy of the spot can be accurate to the pixel level, specifically, the spot diameter corresponding to the 0.5° parallel half-angle of the light source can be sensed by dozens of columns of pixels, so that the measurement accuracy of the parallel half-angle of the light source reaches more than 0.1°.

[0077] On the other hand, it is also possible to avoid opening an observation window on the light metering tube, so that the imaging cavity is protected from interference from other external light and becomes a purer darkroom, which is conducive to improving the fit of the spot image to the actual spot and further improving the data accuracy of parameters such as the acquired spot profile and spot radius.

[0078] It is worth mentioning that the processor for image processing and analysis calculation can refer to the processor on the PC side, that is, the image processing and analysis calculation are performed using the relevant computing software on the PC side. For example, the PC side can be the host of the edge exposure device. Through the measuring device of the present invention and the measuring method of the parallel half-angle of the light source, the parallel half-angle of the exposure light source, the coding light source, etc. of the edge exposure device is periodically monitored so as to timely discover the problem of abnormal conditions of the above light sources. Optionally, for edge exposure equipment, such as equipment for exposing the edge of a display panel, the light metering tube is installed on the machine platform of the edge exposure equipment through a sliding structure so that it can slide to the bottom of the exposure light source or the coding light source. The host drives the light metering tube to slide to the bottom of the exposure light source or the coding light source at preset time intervals to measure the parallel half-angle of the exposure light source or the coding light source, and when the parallel half-angle of the corresponding light source does not meet the preset requirements, the staff is reminded to adjust the relevant parameters of the exposure light source or the coding light source, or replace the exposure light source or the coding light source.

[0079] The present invention also provides a computer-readable storage medium, on which a measuring device control program is stored. When the measuring device control program is executed by a processor, the steps of the aforementioned method for measuring the parallel half-angle of a light source can be executed.

[0080] The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A device for measuring the parallel half angle of a light source, applied to edge exposure equipment, characterized in that: The light measuring tube comprises an imaging cavity provided in the light measuring tube, the imaging cavity has an incident end and an imaging end opposite to each other, the light measuring tube is also provided with an incident hole, the incident hole connects the incident end and the outer side of the light measuring tube, and the minimum diameter of the incident hole ranges from 0.8 mm to 1.2 mm; the light beam emitted by the collimated light source of the edge exposure device can enter the imaging cavity through the incident hole, and a light spot is formed on the end face of the imaging end by using the pinhole imaging principle, and the light spot is used to characterize the parallel half angle of the collimated light source; The photometric tube includes a tube body with an opening at one end, and a first end cap covering the opening of the tube body. The incident hole is arranged in the middle of the first end cap, and the first end cap is movably connected to the tube body to adjust the axis inclination and / or position of the incident hole.

2. The device for measuring the parallel half angle of a light source as claimed in claim 1, characterized in that: The hole wall surface of the incident hole is configured as a frustum surface, and the incident hole is gradually expanded toward the direction close to the imaging end.

3. The device for measuring the parallel half angle of a light source as claimed in claim 1, characterized in that: The end surface of the imaging end is provided with a plurality of concentric annular scale lines with different radii; And / or, the side wall of the light measuring tube is further provided with an observation window connected with the imaging cavity, and the observation window is arranged adjacent to the imaging end.

4. The device for measuring the parallel half angle of a light source as claimed in claim 1, characterized in that: A photosensitive device is provided on the end surface of the imaging end, and the photosensitive device can at least detect the size of the light spot.

5. The device for measuring the parallel half angle of a light source as claimed in claim 4, characterized in that: The photosensitive device includes a CCD detector, the end wall of the imaging cavity is provided with a mounting hole, the lens of the CCD detector is at least partially exposed in the mounting hole, and the end surface of the imaging end is at least partially formed on the photosensitive surface of the lens of the CCD detector; Alternatively, the photosensitive device includes a plurality of position-sensitive detectors, and the plurality of position-sensitive detectors are distributed on the end surface of the imaging end at intervals along the radial direction of the light spot.

6. The device for measuring the parallel half angle of a light source as claimed in claim 1, characterized in that: The device for measuring the parallel half-angle of the light source further comprises a camera arranged in the imaging cavity, and the camera is used for capturing an image of the area where the light spot is located.

7. The device for measuring the parallel half angle of a light source as claimed in claim 1, characterized in that: The light measuring tube also includes a plurality of top screws, which are distributed at intervals along the circumference of the incident hole. The side wall of the first end cover is provided with a threaded hole corresponding to the top screw. The top screw is threadedly connected to the threaded hole, and one end of the top screw passing through the threaded hole abuts against the outer circumferential surface of the tube body.

8. A method for measuring the parallel half angle of a light source, applied to the device for measuring the parallel half angle of a light source as claimed in any one of claims 1 to 7, characterized in that: The method for measuring the parallel half angle of the light source comprises the steps of: Acquire the original image of the light spot on the imaging end and generate an initial light spot; Performing edge detection and contour extraction on the initial light spot to obtain a final light spot; Calculate and obtain the radius r of the final light spot; Substitute the radius r of the final light spot and the height L of the imaging cavity into the parallel half-angle calculation formula, and calculate the parallel half-angle β of the light source, wherein the parallel half-angle calculation formula is Tan β=r / L.

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