Detection device, measuring system and method for infrared lens image evaluation

Abstract

The application provides a detection device, a measuring system and a method for infrared lens image evaluation. The detection device comprises a pot body and a plurality of heating target assemblies. The pot body is provided with a plurality of sliding grooves, and each heating target assembly is slidingly connected to each sliding groove. The application can simultaneously observe the changes in different regions and different radiation intensities in the range of the infrared lens image to be measured by designing the heating target assemblies with adjustable temperature and the positions of the heating target assemblies on the pot body being adjustable. Moreover, the detection device can simulate the real direction of the light path, and the imaging is infinite, so that the detection device has universality for the evaluation of the infrared lens to be measured.

Description

Technical Field

[0001] This invention belongs to the field of image processing technology, and specifically relates to a detection device, measurement system and method for evaluating infrared lens images. Background Technology

[0002] With the development of uncooled infrared thermal imaging technology, infrared thermal imagers have been widely used in civilian fields, including power, security, industry, outdoor applications, and transportation. However, conventional thermal imaging systems, when observing target scenes with strong radiation sources, cannot fully reproduce the radiation differences in high-temperature or low-temperature regions, resulting in the loss of observed targets. To better handle the details of radiation differences in high-temperature and low-temperature regions, a flexible and versatile measurement system is needed for evaluating images of different radiation intensities from various infrared lenses.

[0003] For infrared lenses with small field of view, collimator objectives are currently used to simulate infinity. However, due to limitations in the manufacturing process of optical materials in collimator objective optical systems, they are not suitable for infrared lenses with large field of view. Testing the modulation transfer function (MTF) parameters of infrared lenses usually requires imported equipment, which is not only expensive but also inconvenient for mass production line testing.

[0004] Targets can be used in infrared optical systems such as temperature measurement and sights. Existing targets generally have only one radiation source, and only one radiation area can be seen within the infrared lens image range. This not only makes it impossible to observe the changes in different radiation intensities in different areas within the infrared lens image range at the same time, but also causes thermal diffusion when the radiation source is conducted to the target, resulting in a white image and affecting the calibration accuracy of the algorithm. Alternatively, multiple targets with different thermal radiation sources can be used for control, which places high demands on the space required for the use of some infrared lenses and is not universally applicable. Summary of the Invention

[0005] One of the objectives of this invention is to provide a detection device for evaluating infrared lens images, which can at least solve some of the defects existing in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] The detection device for infrared lens image evaluation includes a pot body and several heating target components. The pot body is provided with multiple sliding grooves, which are arranged sequentially at intervals along the circumference of the pot body and each sliding groove is arranged radially along the pot body. Each heating target component is slidably connected to each sliding groove.

[0008] Furthermore, the radius of curvature of the pot body is equal to the distance between the center of the front end of the infrared lens to be tested and the center of the pot body.

[0009] Furthermore, among the multiple sliding grooves on the pot body, every two sliding grooves form a group, and the two sliding grooves in each group are arranged symmetrically with respect to the center of the pot body.

[0010] Furthermore, the heating target assembly includes multiple target plates, a fixing base, and a heating module and a parallel light tube disposed on the fixing base. Each of the target plates is detachably installed at the light-incident end of the parallel light tube. The target plates are provided with distinguishable targets, and the light-exit end of the parallel light tube is located on one side of the inner arc surface of the pot body.

[0011] Furthermore, the heating target assembly connected to the slide groove also includes a support fixing block slidably disposed on the slide groove.

[0012] Another object of the present invention is to provide a measurement system for evaluating infrared lens images, including a fixture mechanism for mounting the infrared lens under test, a drive mechanism for adjusting the focal length of the infrared lens under test, and the aforementioned detection device; the fixture mechanism is mounted on the drive mechanism, the pot body is arranged opposite to the fixture mechanism, and the center of the pot body is located on the optical axis of the infrared lens under test.

[0013] Furthermore, the tooling fixture mechanism includes a fixed base and a bracket mounted on the fixed base. A lens positioning plate for positioning and mounting the infrared lens to be tested is detachably connected to the bracket. A focusing fixture that can be docked with the infrared lens to be tested for focusing is provided above the lens positioning plate. The focusing fixture is detachably connected to the lens positioning plate.

[0014] Furthermore, the driving mechanism includes a rotating component that drives the focusing fixture to rotate around the central axis of the focusing fixture, and an X-axis translation component, a Y-axis translation component, a Z-axis lifting component, a horizontal rotation component, and a vertical pitch component that respectively drive the tooling fixture mechanism to rotate horizontally and pitch vertically along the X-axis, Y-axis, Z-axis, and vertically.

[0015] Another object of the present invention is to provide a measurement method for evaluating infrared lens images, implemented based on the above-described measurement system, specifically including the following steps:

[0016] S1. The infrared lens to be tested is mounted on the tooling fixture mechanism, and the inner arc surface of the pot of the detection device is arranged facing the infrared lens to be tested, and the center of the pot is located on the optical axis of the infrared lens to be tested.

[0017] S2. Adjust the position of the heating target assembly in the corresponding slide according to the test requirements, and control the temperature of each heating target assembly individually so that the target pattern of each heating target assembly is imaged on the detector of the infrared lens under test.

[0018] S3. Based on the clarity of the target pattern image obtained on the detector, control the drive mechanism to adjust the focal length of the infrared lens under test so that the target pattern image obtained on the detector is as clear as possible.

[0019] S4. Using the clearest target pattern obtained in step S3, calculate the performance parameters of the infrared lens under test.

[0020] Furthermore, the performance parameters of the infrared lens under test include at least one of MTF data curve, sharpness, and contrast.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] (1) The detection device for evaluating infrared lens images provided by the present invention is designed with a temperature-adjustable heating target component and an adjustable position of the heating target component on the pot body, thereby achieving the purpose of simultaneously observing the changes in different radiation intensities in different areas within the range of the infrared lens image to be tested. Moreover, the detection device can simulate the real direction of the light path and image at infinity, and has universality for evaluating the infrared lens to be tested.

[0023] (2) The measurement system for infrared lens image evaluation provided by this invention is designed with a drive mechanism to drive the tooling fixture mechanism to move, simulating the manual focusing production of the infrared lens under test, thereby realizing an intelligent production mode in which machinery replaces manual labor, making the product quality more stable and the production efficiency higher.

[0024] (3) The measurement system for infrared lens image evaluation provided by the present invention integrates automatic focusing of infrared lens and MTF test image evaluation, realizes machine automation, and uses image algorithm to convert the focal length and sharpness of infrared lens adjustment into MTF curve, thereby improving the stability of infrared lens imaging quality and increasing production efficiency.

[0025] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the detection device for infrared lens image evaluation according to the present invention;

[0027] Figure 2 This is a front view of the detection device for infrared lens image evaluation according to the present invention;

[0028] Figure 3 This is a side view of the detection device for infrared lens image evaluation according to the present invention;

[0029] Figure 4 This is a schematic diagram of the pot body in this invention;

[0030] Figure 5 This is a first-view structural schematic diagram of the heating target assembly in this invention;

[0031] Figure 6 This is a second-view structural schematic diagram of the heating target assembly in this invention;

[0032] Figure 7 This is a schematic diagram of the target plate in this invention, wherein (a) is a square target plate and (b) is a four-bar target plate;

[0033] Figure 8 This is a schematic diagram of the measurement system for infrared lens image evaluation according to the present invention;

[0034] Figure 9 This is a schematic diagram of the tooling fixture mechanism in this invention;

[0035] Figure 10 This is a cross-sectional view of the tooling fixture mechanism in this invention;

[0036] Figure 11 This is a schematic diagram of the assembly structure of the tooling fixture mechanism and the drive mechanism in this invention;

[0037] Figure 12 This is a front view of the assembly of the tooling fixture mechanism and the drive mechanism in this invention;

[0038] Figure 13 This is a schematic diagram of the six-axis motion of the drive mechanism in this invention.

[0039] Explanation of reference numerals in the attached drawings: 1. Pot body; 2. Slide rail; 3. Heating target assembly; 4. Fixture; 5. Adjusting slide; 6. Adjusting knob; 7. Cooling fan; 8. Heat sink; 9. Heating plate; 10. Collimator; 11. Upper locking block; 12. Upper fixing block; 13. Groove; 14. Lower fixing block; 15. Target plate; 16. Target plate fixing block; 17. Positioning block; 18. Lower locking block; 19. Adjusting component; 20. Worktable; 21. Slide rail; 22. Tooling fixture mechanism; 23. Drive mechanism; 24. Focusing fixture; 25. Notch; 26. Focusing cover; 27. Focusing guide post; 28. Focusing mounting plate; 29. ​​Lens positioning plate; 30. First 31. First buckle shaft; 32. Second buckle; 33. Second buckle shaft; 34. Bracket; 35. Fixed base; 36. Infrared lens mechanism; 37. Cross protrusion; 38. Cross groove; 39. Infrared lens under test; 40. Z-axis drive motor; 41. Lifting platform; 42. X-axis translation slide plate; 43. Fixed block; 44. X-axis drive motor; 45. Horizontal rotation drive motor; 46. Horizontal rotation platform; 47. Y-axis support plate; 48. Y-axis translation slide plate; 49. Y-axis drive motor; 50. Rotation drive motor; 51. Circular rotating block; 52. Locking block; 53. Pitch drive motor; 54. Connecting plate; 55. U-shaped bracket. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation", "connection", and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, an abutting connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0044] Example 1:

[0045] like Figure 1 , Figure 2 and Figure 3 As shown, this embodiment provides a detection device for infrared lens image evaluation, including a pot body 1 and a plurality of heating target assemblies 3. The pot body 1 is provided with multiple sliding grooves 2, which are arranged sequentially at intervals along the circumference of the pot body 1 and radially along the pot body 1. Each heating target assembly 3 is slidably connected to its respective sliding groove 2. Preferably, one heating target assembly 3 can be located at the center of the pot body 1, and the remaining heating target assemblies 3 can be slidably connected to their respective sliding grooves 2. In this embodiment, the pot body 1 adopts a concave structural design, with the concave surface facing the infrared lens side. The concave pot body 1 not only facilitates the large field-of-view lens to image at one time and evaluate the image quality of multiple fields of view, but also simulates the real direction of the light path that is more in line with the actual situation, achieving an infinity imaging effect. At the same time, by designing multiple heating target components 3 to move radially along the pot body 1 within the slide groove 2, and the temperature of each heating target component 3 can be independently controlled, the temperature of the target points in different areas can be adjusted according to specific actual needs. This achieves the purpose of simultaneously observing the changes in different radiation intensities in different areas within the range of the infrared lens image under test, while ensuring that the target point temperature does not change with temperature changes, resulting in clear imaging.

[0046] Specifically, in order to ensure that the energy radiated by the heating target assembly 3 on the pot body 1 is concentrated at the end of the infrared lens to be tested, it is necessary to consider the radius of curvature of the pot body 1. In this embodiment, the radius of curvature of the pot body 1 is designed to be approximately equal to the distance between the center of the front end of the infrared lens to be tested and the center of the pot body 1. Specifically, the radius of curvature of the pot body 1 is about 600mm; wherein, the center of the front end of the infrared lens to be tested is the center of the convex surface of the lens facing the side of the pot body 1.

[0047] like Figure 4 As shown, in the plurality of sliding grooves 2 on the pot body 1, every two sliding grooves 2 form a group, and the two sliding grooves 2 in each group are arranged symmetrically with respect to the center of the pot body 1. Preferably, it includes at least two sliding grooves 2 on both sides of the center of the pot body 1 in the horizontal direction and another two sliding grooves 2 on both sides of the center of the pot body 1 in the vertical direction. Specifically, as shown... Figure 4As shown in the figure, in this embodiment, 8 sliding grooves 2 are provided on the pot body 1, arranged in a "rice" shape. One heating target component is provided at each of the 8 sliding grooves 2 and at the center of the pot body 1, so a total of 9 target points can be set. The temperature of each target point can be adjusted independently, and the target points located in the sliding grooves 2 can slide along the sliding grooves 2 to change their positions on the image plane. Setting a heating target component 3 at the center of the pot body 1 is beneficial for the image evaluation of the minimum thermal temperature difference resolution in the central field of view. At the same time, it is also beneficial for data collection of the spatial frequency response (SFR) in the central field of view and evaluation of the quality of the central image.

[0048] As a specific implementation method, as Figure 5 and Figure 6 shown, the heating target component 3 includes a variety of target plates 15, a fixed seat 4, a heating module and a collimator 10 provided on the fixed seat 4. Each of the target plates 15 is detachably installed at the light input end of the collimator 10. A distinguishable target is provided on the target plate 15. The light output end of the collimator 10 penetrates through the center / sliding groove 2 of the pot body 1 and is located on one side of the inner arc surface of the pot body 1. Among them, the heating module is used as a heat radiation source, a temperature difference is generated between the heating module and the target plate 15, and the infrared light formed by the target on the target plate 15 is emitted in a parallel light manner through the collimator 10 to simulate infinity and form an image on the detector of the infrared lens, so that the MTF test of the待测 infrared lens can be carried out; at the same time, a detachable connection method is adopted between the configured variety of target plates 15 and the collimator 10. When different types of heating targets are required for MTF testing of different infrared lens products, only the corresponding target plate 15 with the target pattern needs to be selected and replaced according to the actual use situation, which is convenient to operate, so as to meet the compatibility of heating targets of different types of products and achieve the purpose of multi-purpose use of one machine, saving costs and improving utilization rates.

[0049] Optionally, as Figure 5 and Figure 6 shown, the heating module includes a semiconductor refrigerator and a heating plate 9. The semiconductor refrigerator is installed on one side plate surface of the heating plate 9, and the other side plate surface of the heating plate 9 is arranged facing the target plate 15; during operation, the semiconductor refrigerator is externally connected to a controller, and the heating temperature of the semiconductor refrigerator is controlled by the controller to make the heating plate 9 generate heat, so as to achieve the purpose of heating the target plate 15, and the target temperature can be accurately controlled by using the semiconductor refrigerator, and the temperature range is adjustable from 0°C to 70°C, and its temperature control accuracy can reach ±0.1°. Among them, the heating plate 9 can be but is not limited to a heating aluminum plate, and the heating plate 9 and the semiconductor refrigerator are connected and fixed through heat-conducting silicone grease.

[0050] In the optimized technical solution, the heating module further includes a cooling component for maintaining the temperature balance of the thermoelectric cooler. In some embodiments, the cooling component includes a cooling fan 7 and a heat sink 8. The side of the thermoelectric cooler facing away from the heating plate 9 is fixed to the heat sink 8 with screws. The cooling fan 7 is fixedly connected to the side of the heat sink 8 facing away from the thermoelectric cooler via a fan mounting sheet metal. The thermoelectric cooler is cooled by the heat sink 8 and the cooling fan 7 to maintain the temperature balance of the thermoelectric cooler.

[0051] A further optimized technical solution involves designing the spacing between the heating module and the target plate 15 to be adjustable, thereby ensuring the uniformity of target imaging. One specific adjustment method is as follows: Figure 5 and Figure 6 As shown, an adjustment slide 5 is installed on the fixed base 4 along the axis of the parallel light tube 10. The heating module is slidably installed on the adjustment slide 5. The adjustment knob 6 on the adjustment slide 5 controls the heating module to move closer to or further away from the target plate 15, thereby achieving the purpose of controlling the distance between the heating module and the target plate 15.

[0052] For the detachable connection between the target plate 15 and the collimator 10, a target plate fixing block 16 can be provided at the light-incident end of the collimator 10. The target plate fixing block 16 has a target plate 15 mounting position, and each target plate 15 adopts a plate shape adapted to the target plate mounting position. The online target plate 15 is detachably mounted on the target plate mounting position. Preferably, a fixing adapter block (not shown in the figure) is also provided at the light-incident end of the collimator 10. One end of the fixing adapter block is threadedly connected to the end of the collimator 10, and the other end of the fixing adapter block is threadedly connected to the target plate fixing block 16. The target plate 15 can be made with corresponding target patterns according to actual use. For example, the targets on the target plate 15 can adopt, but are not limited to, the following... Figure 7 The square target and the four-bar target shown can be expanded to include targets of various other shapes and sizes. When it is necessary to switch between different scene background targets, simply replace the target fixing block with a different target plate 15.

[0053] Specifically, the collimator 10 is fixedly mounted on the mounting base 4 via a support assembly. In some embodiments, the support assembly includes an upper locking block 11 and a lower locking block 18. Both the upper locking block 11 and the lower locking block 18 are provided with limiting slots for engaging and fixing the collimator 10. The lower locking block 18 is fixedly mounted on one end of the mounting base 4, and the upper locking block 11 is placed on top of the lower locking block 18. The upper locking block 11 and the lower locking block 18 are fixed together by a pin. The limiting slots of the upper locking block 11 and the lower locking block 18 can enclose and form a hollow area through which the collimator 10 passes. This hollow area can cooperate with a certain part of the outer shell of the collimator 10, thereby engaging and fixing the collimator 10. Optionally, positioning blocks 17 can be symmetrically provided on the outer wall of the collimator 10. Correspondingly, positioning block slots adapted to the positioning blocks 17 are provided in the limiting slots of the upper locking block 11 and the lower locking block 18, ensuring the installation accuracy and stability of the collimator 10.

[0054] Optionally, the collimator 10 is designed to be tapered, and the diameter of the light-inlet end of the collimator 10 is smaller than the diameter of the light-outlet end of the collimator 10; at the same time, the collimator 10 is designed to include at least two lenses to improve aberration correction.

[0055] To enable the heating target assembly 3 to slide within the groove 2 of the pot body 1, the heating target assembly 3 connected to the groove 2 also includes a support and fixing block slidably disposed on the groove 2. Specifically, the support and fixing block includes an upper fixing block 12 and a lower fixing block 14 stacked along the axis of the parallel light tube 10. The upper fixing block 12 is mounted on a support assembly for fixing the parallel light tube 10 and is located on the outer arc surface side of the pot body 1. The lower fixing block 14 is located on the inner arc surface side of the pot body 1. The lower fixing block 14 and the upper fixing block 12 are detachably fixed by screws. The upper fixing block 12 and the lower fixing block 14 have a limiting through hole at their center for the parallel light tube 10 to pass through. The lower fixing block 14 and the upper fixing block 12 form a groove 13 on both sides of the clamping slide 2 sidewall. When the screw fastening action between the lower fixing block 14 and the upper fixing block 12 is loosened, the force of the lower fixing block 14 and the upper fixing block 12 clamping the slide 2 sidewall decreases, and the supporting fixing block can slide along the slide 2, thereby adjusting the position of the heating target assembly 3. After the position adjustment is completed, the screw between the lower fixing block 14 and the upper fixing block 12 is tightened to clamp the slide 2 sidewall, thereby fixing the heating target assembly 3 in the designed position of the pot body 1.

[0056] Preferably, an adjusting member 19 for pushing against the supporting fixing block is installed on the lower locking block 18 of the supporting component. When the assembled parallel light tube 10 is installed on the pot body 1 through the supporting fixing block, the adjusting member 10 pushes against the supporting fixing block to adjust the overall vertical angle of the assembled parallel light tube 10 so that it can meet the test installation angle requirements. The adjusting member 19 can be, but is not limited to, a micrometer.

[0057] Example 2:

[0058] like Figure 8 As shown, this embodiment provides a measurement system for evaluating infrared lens images, including a fixture mechanism 22 for mounting the infrared lens under test, a drive mechanism 23 for adjusting the focal length of the infrared lens under test, and the detection device in Embodiment 1 above; the fixture mechanism 22 is mounted on the drive mechanism 23, and the drive mechanism 23 drives the fixture mechanism 22 to move, thereby realizing automatic focusing of the infrared lens under test. The pot body 1 is arranged opposite to the fixture mechanism 22, and the center of the pot body 1 is located on the optical axis of the infrared lens under test.

[0059] Specifically, the measurement system in this embodiment also includes a workbench 20. The pot body 1 of the detection device is supported and installed on the workbench 20 by a bracket. The tooling fixture mechanism 22 is installed on the workbench 20 by a drive mechanism 23. Preferably, the workbench 20 is provided with a slide rail 21. The bracket supporting the pot body 1 is slidably connected to the slide rail 21, thereby adjusting the distance between the pot body 1 and the tooling fixture mechanism 22.

[0060] As a specific implementation method, such as Figure 9 and Figure 10 As shown, the tooling fixture mechanism 22 includes a fixed base 35, a bracket 34 mounted on the fixed base 35, and an infrared lens mechanism 36. A lens positioning plate 29 for positioning and mounting the infrared lens 39 to be tested is detachably connected to the bracket 34. A focusing fixture 24, which can be focused and docked with the infrared lens 39 to be tested, is provided above the lens positioning plate 29. The focusing fixture 24 is detachably connected to the lens positioning plate 29. In this embodiment, the lens positioning plate 29 and the bracket 34 are detachably connected, allowing for the replacement of different infrared lenses 39 to be tested. During installation, it is only necessary to electrically connect the infrared lens 39 to the infrared lens mechanism 36; the end of the infrared lens 39 to be tested docks with the focusing fixture 24, and the movement of the focusing fixture 24 achieves automatic focusing of the infrared lens 39 to be tested.

[0061] Specifically, such as Figure 10As shown, the focusing fixture 24 is a hollow truncated cone structure. The smaller top surface of the truncated cone structure is aligned with the end face of the infrared lens 39 to be tested. Regarding the specific alignment method, in some embodiments, a cross protrusion 37 can be provided on the smaller top surface of the focusing fixture 24, and a cross groove 38 is provided on the end face of the infrared lens 39 to be tested. The cross protrusion 37 and the cross groove 38 are engaged to complete the alignment of the focusing fixture 24 and the infrared lens 39 to be tested. The axes of the focusing fixture 24 and the infrared lens 39 to be tested are on the same straight line. The larger bottom surface of the truncated cone structure is arranged facing the pot body 1 of the detection device. At the same time, notches 25 are symmetrically opened on this larger bottom surface for connection with the drive mechanism 23, thereby realizing the automatic focusing of the infrared lens 39 to be tested by driving the focusing fixture 24 through the drive mechanism 23. In an optimized manner, multiple holes are equally spaced along the circumference of the side wall of the focusing fixture 24 to reduce the weight of the focusing fixture 24, thereby improving the motion accuracy of the focusing fixture 24 and ensuring the accuracy of automatic focusing of the infrared lens 39 under test. At the same time, the design of the holes also makes it convenient to observe the positional changes of the lens 39 under test.

[0062] For fixing the position of the focusing fixture 24, this embodiment uses a focusing mounting assembly to install and fix it. In some embodiments, such as Figure 9 and Figure 10As shown, the focusing mounting assembly includes a focusing cover 26, a focusing guide post 27, and a focusing mounting plate 28. The focusing cover 26 fixes the focusing fixture 24 onto the focusing mounting plate 28, and the focusing cover 26 limits the installation of the focusing fixture 24. The four sides of the focusing mounting plate 28 are connected to the lens positioning plate 29 through the focusing guide post 27. At the same time, the focusing mounting plate 28 is provided with a preset gap along the focusing guide post 27. The movement range of the lens 39 under test is determined by the distance between the focusing mounting plate 28 and the focusing guide post 27. The preset gap ranges from 1mm to 10mm. In this embodiment, the preset gap is 3mm. By fixing and guiding the position of the focusing fixture 24 through the focusing cover 26, the focusing guide post 27, and the focusing mounting plate 28, the consistency of the focusing fixture 24 and the infrared lens 39 under test can be ensured each time. The two opposite side walls of the focusing mounting plate 28 are connected to the first buckle through the first buckle shaft 31. 30. One end of the first latch 30 is connected to the focusing mounting plate 28 via a spring, and the other end of the first latch 30 has a fastening part that engages with the side wall of the lens positioning plate 29. When the focusing fixture 24 is docked with the infrared lens 39 to be tested, the cross protrusion 37 at the end of the focusing fixture 24 is aligned with the cross groove 38 of the infrared lens 39 to be tested, and then the fastening part of the first latch 30 is fastened and fixed to the lens positioning plate 29, thus completing the docking of the focusing fixture 24 with the infrared lens 39 to be tested; When replacing the infrared lens 39 to be tested, press one end of the spring connected to the first latch 30. At this time, the first latch 30 rotates around the first latch shaft 31, and the latching part of the first latch 30 is lifted, and the focusing mounting plate 28 and the lens positioning plate 29 are released from fixation. At this time, the position of the focusing mounting plate 28 can be moved along the focusing guide post 27, so that the cross protrusion 37 at the end of the focusing fixture 24 disengages from the cross groove 38 of the infrared lens 39 to be tested, thereby completing the replacement of the infrared lens 39 to be tested.

[0063] The lens positioning plate 29 is mainly used to limit the position of the infrared lens 39 under test. The lens positioning plate 29 is placed on the bracket 34, and its installation position on the bracket 34 makes it easy for the infrared lens 39 under test to be electrically connected to the infrared lens mechanism 36 on the fixed base 35. The fixing method between the lens positioning plate 29 and the bracket 34 is a snap-fit ​​fixing method in some embodiments. Specifically, the two opposite side walls of the bracket 34 are connected to the second snap-fit ​​32 by the second snap-fit ​​shaft 33, and one end of the second snap-fit ​​32 is... The spring is connected to the side wall of the bracket 34. The other end of the second buckle 32 has a fastening part that engages with the side wall of the lens positioning plate 29. When the lens positioning plate 29 is fixed, the fastening part of the second buckle 32 is fastened and fixed to the lens positioning plate 29. When the infrared lens 39 to be tested needs to be replaced, one end of the spring connected to the second buckle 32 is pressed. At this time, the second buckle 32 rotates around the second buckle shaft 33, and the fastening part of the second buckle 32 is lifted, releasing the fixation between the lens positioning plate 29 and the bracket 34. At this time, the replacement of the infrared lens 39 to be tested can be completed. In this embodiment, by assembling a double-layer quick-release buckle, that is, the lens positioning plate 29 is fastened and fixed to the focusing mounting plate 28 and the bracket 34 respectively, the quick clamping and fixing of the infrared lens 39 to be tested is realized, improving production efficiency.

[0064] As a specific implementation method, such as Figure 11 , Figure 12 and Figure 13 As shown, the driving mechanism 23 includes a rotating component that drives the focusing fixture 24 to rotate around the central axis (i.e., the R-axis) of the focusing fixture 24, and an X-axis translation component, a Y-axis translation component, a Z-axis lifting component, a horizontal rotation component, and a vertical tilt component that respectively drive the tooling fixture mechanism 22 to rotate horizontally and tilt vertically along the X-axis, Y-axis, Z-axis, and vertical axes. The rotating component drives the focusing fixture 24 to rotate around its central axis, thereby causing the lens of the lens under test 39 to move along the central axis of the focusing fixture 24, achieving automatic focusing of the infrared lens 39 under test. The X-axis translation component, Y-axis translation component, Z-axis lifting component, horizontal rotation component, and vertical tilt component assist in fine-tuning in various directions during the focusing process, ensuring that the focal length of the infrared lens 39 under test reaches the ideal value and the image is clearest.

[0065] In some embodiments, such as Figure 11As shown, the X-axis translation component is mounted on the Z-axis lifting component, the horizontal rotation component is slidably connected to the X-axis translation component, the fixed base of the tooling fixture mechanism 22 is slidably connected to the Y-axis translation component, the Y-axis translation component is mounted on the horizontal rotation component via the vertical pitch component, and the rotation component is connected to the focusing fixture 24 of the tooling fixture mechanism 22. During the focusing process, the Z-axis lifting assembly drives the entire assembly on it to move up and down along the Z-axis direction, realizing the Z-axis movement of the tooling fixture mechanism 22. The X-axis translation assembly drives the entire assembly on the horizontal rotation assembly to translate along the X-axis direction, realizing the X-axis movement of the tooling fixture mechanism 22. The horizontal rotation assembly drives the entire assembly on the vertical pitch assembly to rotate left and right on the horizontal plane, realizing the left and right rotation of the tooling fixture mechanism 22. The vertical pitch assembly drives the entire assembly on the Y-axis translation assembly to pitch and rotate, realizing the pitch and rotation of the tooling fixture mechanism 22. The Y-axis translation assembly drives the entire tooling fixture mechanism 22 to translate along the X-axis direction. The rotation assembly drives the focusing fixture 24 to move, realizing the automatic focusing of the infrared lens 39 under test.

[0066] Specifically, the Z-axis lifting assembly includes a Z-axis drive motor 40 and a lifting platform 41. The Z-axis drive motor 40 is located below the lifting platform 41 and drives the lifting platform 41 to move up and down. The X-axis translation assembly includes a fixed block 43, an X-axis drive motor 44, and an X-axis translation slide plate 42. The fixed block 43 is fixedly installed on the lifting platform 41 of the Z-axis lifting assembly. The upper surface of the fixed block 43 is provided with a groove arranged along the X-axis direction. The bottom of the X-axis translation slide plate 42 is provided with a slider that cooperates with the groove. The X-axis drive motor 44 is fixedly installed on the fixed block 43. The movable end of the X-axis drive motor 44 is connected to the X-axis translation slide plate 42, driving the X-axis translation slide plate 42 to move along the X-axis direction. The horizontal rotation assembly includes a horizontal rotation drive motor 45 and a horizontal rotation platform 46. The horizontal rotation platform 46 is installed on the X-axis translation slide plate 42 of the X-axis translation assembly. The horizontal rotation drive motor 45 is connected to the horizontal rotation platform 46 and drives the horizontal rotation platform 46 to rotate left and right in the horizontal plane. The Y-axis translation assembly includes a Y-axis support plate 47, a Y-axis drive motor 49, and a Y-axis translation slide plate 48. The Y-axis support plate 47 is provided with a slider arranged along the Y-axis direction. The bottom of the Y-axis translation slide plate 48 is slidably connected to the slider of the Y-axis support plate 47. The Y-axis drive motor 49 is connected to the Y-axis translation slide plate 48 and drives the Y-axis translation slide plate 48 to move along the Y-axis direction. The fixed base 35 of the tooling fixture mechanism 22 is fixedly installed on the Y-axis translation slide plate 48, so that the movement of the Y-axis translation slide plate 48 drives the tooling fixture mechanism 22 to move as a whole along the Y-axis direction. The vertical pitch assembly includes a U-shaped bracket 55, a connecting plate 54, and a pitch drive motor 53. The bottom of the U-shaped bracket 55 is fixedly mounted on the horizontal rotation platform 46 of the horizontal rotation assembly. There are two connecting plates 54, the lower ends of which are fixedly connected to the Y-axis support plate 47 of the Y-axis translation assembly, and the upper ends of which are rotatably connected to the two side walls of the U-shaped bracket 55 via rotating shafts. The pitch drive motor 53 drives the rotating shafts to rotate. The rotation assembly includes a rotation drive motor 50 and an annular rotating block 51. Two locking blocks 52 are symmetrically connected to one side of the annular rotating block 51. The two locking blocks 52 are respectively engaged and fixed with the two notches 25 on the end face of the focusing fixture 24. The rotation drive motor 50 is connected to the annular rotating block 51 through a transmission component, driving the annular rotating block 51 to rotate, thereby driving the focusing fixture 24 to rotate, realizing automatic focusing of the infrared lens 39 under test.

[0067] Specifically, in this embodiment, the maximum rotation angle of the rotating component is designed to be 360°, the maximum stroke of the X-axis translation component is 300mm, the maximum stroke of the Y-axis translation component is 20mm, the maximum stroke of the Z-axis lifting component is 150mm, the maximum left and right rotation angle of the horizontal rotating component is ±40°, and the maximum rotation angle of the vertical pitch component is ±60°.

[0068] The measurement method using the measurement system of this embodiment for infrared lens image evaluation specifically includes the following steps:

[0069] S1. The infrared lens 39 to be measured is installed on the tooling fixture mechanism 22, and the inner arc surface side of the pot body 1 of the detection device is arranged facing the infrared lens 39 to be measured, and the center of the pot body 1 is located on the optical axis of the infrared lens 39 to be measured.

[0070] S2. Adjust the position of the heating target component 3 in the corresponding chute 2 according to the test requirements, and at the same time independently control the temperature of each heating target component 3 so that the target pattern of each heating target component 3 is imaged on the detector of the infrared lens 39 to be measured.

[0071] S3. According to the clarity of the target pattern imaging obtained on the detector, control the driving mechanism 23 to adjust the focal length of the infrared lens 39 to be measured so that the target pattern imaging obtained on the detector reaches the clearest.

[0072] S4. Use the clearest target pattern imaging obtained in step S3 to calculate the performance parameters of the infrared lens 39 to be measured. The performance parameters of the infrared lens 39 to be measured include but are not limited to the MTF data curve, clarity, and contrast.

[0073] Specifically, when evaluating the MTF data curve of the infrared lens 39 to be measured, the target board 15 in the heating target component 3 on the pot body 1 is a square target, and a square target pattern imaging is obtained, and the MTF value is calculated by the inclined edge method. When evaluating the clarity of the infrared lens 39 to be measured, the target board 15 in the heating target component 3 can be replaced with a four-bar target. When evaluating the contrast of the infrared lens 39 to be measured, the temperatures of several heating target components 3 on the pot body 1 are set to different temperatures so that different regional radiation intensities are presented on the target pattern imaging. For example, in this embodiment, the temperatures of the 9 heating target components 3 arranged in a "rice" shape on the pot body 1 can be set to three temperature modes of low, medium, and high, so as to reflect three different regional radiation intensities of low, medium, and high on the target pattern imaging, and thus judge the contrast of the infrared lens to be measured.

[0074] In summary, the measurement system for infrared lens image evaluation provided in this embodiment designs a driving mechanism to drive the tooling fixture mechanism to move, simulating the manual focusing production of the infrared lens to be measured, thereby realizing an intelligent production mode of replacing manual labor with machinery. At the same time, it realizes the integration of automatic focusing of the infrared lens and MTF test image evaluation, realizes machine automation, uses image algorithms, converts the focal length clarity adjusted by the infrared lens into an MTF curve, improves the imaging quality stability of the infrared lens, and has high production efficiency.

[0075] The above examples are merely illustrative of the present invention and do not constitute a limitation on the scope of protection of the present invention. All designs that are the same as or similar to the present invention are within the scope of protection of the present invention.

Claims

1. A detection device for evaluating infrared lens images, characterized in that: The device includes a pot body and several heating target assemblies. The pot body has multiple sliding grooves, which are arranged sequentially at intervals along the circumference of the pot body and are arranged radially along the pot body. Each heating target assembly is slidably connected to each sliding groove. Each heating target assembly includes multiple target plates, a fixing base, a heating module and a parallel light tube disposed on the fixing base. Each target plate is detachably mounted on the light-incident end of the parallel light tube. The target plate has a recognizable target. The light-exit end of the parallel light tube is located on one side of the inner arc surface of the pot body.

2. The detection device for infrared lens image evaluation as described in claim 1, characterized in that: The radius of curvature of the pot body is equal to the distance between the center of the front end of the infrared lens to be tested and the center of the pot body.

3. The detection device for infrared lens image evaluation as described in claim 1, characterized in that: In the multiple sliding grooves on the pot body, every two sliding grooves form a group, and the two sliding grooves in each group are arranged symmetrically with respect to the center of the pot body.

4. The detection device for infrared lens image evaluation as described in claim 1, characterized in that: The heating target assembly connected to the slide groove also includes a support fixing block slidably disposed on the slide groove.

5. A measurement system for evaluating infrared lens images, characterized in that: The device includes a fixture mechanism for mounting an infrared lens under test, a drive mechanism for adjusting the focal length of the infrared lens under test, and a detection device as described in any one of claims 1-4; the fixture mechanism is mounted on the drive mechanism, the pot body is arranged opposite to the fixture mechanism, and the center of the pot body is located on the optical axis of the infrared lens under test defined by the fixture mechanism.

6. The measurement system for infrared lens image evaluation as described in claim 5, characterized in that: The tooling fixture mechanism includes a fixed base and a bracket set on the fixed base. A lens positioning plate for positioning and installing the infrared lens to be tested is detachably connected to the bracket. A focusing fixture that can be docked with the infrared lens to be tested for focusing is provided above the lens positioning plate. The focusing fixture is detachably connected to the lens positioning plate.

7. The measurement system for infrared lens image evaluation as described in claim 6, characterized in that: The driving mechanism includes a rotating component that drives the focusing fixture to rotate around the central axis of the focusing fixture, and an X-axis translation component, a Y-axis translation component, a Z-axis lifting component, a horizontal rotation component, and a vertical pitch component that drive the tooling fixture mechanism to rotate horizontally and pitch vertically along the X-axis, Y-axis, Z-axis, respectively.

8. A measurement method for evaluating infrared lens images, characterized in that, The implementation of the measurement system according to any one of claims 5-7 specifically includes the following steps: S1. The infrared lens to be tested is mounted on the tooling fixture mechanism, and the inner arc surface of the pot of the detection device is arranged facing the infrared lens to be tested, and the center of the pot is located on the optical axis of the infrared lens to be tested. S2. Adjust the position of the heating target assembly in the corresponding slide according to the test requirements, and control the temperature of each heating target assembly individually so that the target pattern of each heating target assembly is imaged on the detector of the infrared lens under test. S3. Based on the clarity of the target pattern image obtained on the detector, control the drive mechanism to adjust the focal length of the infrared lens under test so that the target pattern image obtained on the detector is as clear as possible. S4. Using the clearest target pattern obtained in step S3, calculate the performance parameters of the infrared lens under test.

9. The measurement method as described in claim 8, characterized in that: The performance parameters of the infrared lens under test include at least one of MTF data curve, sharpness, and contrast.

Images