Polarization adjustment device and polarization imaging device

Abstract

The application provides a polarization adjusting device and a polarization imaging device. The polarization adjusting device comprises a filter assembly, a movable grating assembly, a fixed grating assembly, a polarization assembly and a connecting structure arranged in sequence. The connecting structure is used for sequentially fixing and connecting the filter assembly, the movable grating assembly, the fixed grating assembly and the polarization assembly. The filter assembly comprises a filter and a filter pressing ring. The filter is used for improving the purity of incident light. The filter pressing ring is used for fixing the filter. The polarization adjusting device is used for adjusting the polarization direction of incident light. By adding the filter in the polarization adjusting device, the influence of the remaining wave bands other than the incident light on the polarization imaging can be reduced. In the polarization imaging device, by setting the polarization adjusting device as a component which can be detached from the imaging lens group, the polarization adjusting device can be quickly adapted to common lenses of the same aperture type, and the common lenses can be converted into polarization imaging lenses.

Description

Technical Field

[0001] This application relates to the field of polarization imaging technology, and more specifically, to a polarization adjustment device and a polarization imaging device. Background Technology

[0002] In existing optical imaging equipment, the polarization adjustment system is integrated into the imaging lens assembly. When the polarization adjustment system needs to be repaired, replaced, or upgraded, the operator needs to have professional optical knowledge and optical instrument operation skills, and also needs to use special tools to disassemble and assemble the polarization adjustment system. Slight carelessness may lead to damage to the components.

[0003] Furthermore, this integration method may damage the optical system of the original imaging lens assembly. During the integration of the polarization adjustment system, the imaging lens assembly may need to be adjusted to adapt to the polarization adjustment system, which may lead to problems such as increased aberrations, reduced resolution, and decreased contrast, thereby affecting image quality. When the polarization adjustment system malfunctions and needs repair or replacement, the repeated disassembly and adjustment of the original optical system will reduce the optical performance of the imaging lens assembly, affecting the stability and reliability of the optical imaging equipment. Utility Model Content

[0004] In order to overcome at least the above-mentioned deficiencies in the prior art, the purpose of this application is to provide a polarization adjustment device, the polarization adjustment device comprising a filter component, a movable grating component, a fixed grating component, and a polarization component arranged in sequence, and a connection structure, the connection structure being used to fix the filter component, the movable grating component, the fixed grating component, and the polarization component in sequence. The filtering assembly includes a filter and a filter retainer ring; the filter is used to improve the purity of the incident light; the filter retainer ring is used to fix the filter. The polarization adjustment device is used to adjust the polarization direction of the incident light.

[0005] In one possible implementation, the movable grating assembly includes a movable grating sheet and a movable grating base; The fixed grating assembly includes a fixed grating sheet and a fixed grating base; The surfaces of the movable grating sheet and the fixed grating sheet have the same univariate subwavelength periodic structure, and the grating period directions of the movable grating sheet and the fixed grating sheet are the same; The polarization adjustment device further includes a driver and a drive controller. The driver is used to drive the movable grating sheet to move so that the movable grating sheet and the fixed grating sheet are relatively displaced in the grating period direction. The drive controller is used to control the driver to drive the movable grating sheet to reciprocate within a preset stroke range.

[0006] In one possible implementation, the filtering assembly includes various types of the filters.

[0007] In one possible implementation, the filter assembly is detachably connected to the connection structure.

[0008] In one possible implementation, the preset travel distance ensures that the moving grating sheet never deviates from the effective light transmission aperture of the fixed grating sheet.

[0009] In one possible implementation, the preset travel is equal to half the period of the moving grating sheet.

[0010] In one possible implementation, the polarization adjustment device includes a front extinction tube, the filter assembly, the movable grating assembly, the fixed grating assembly, the polarization assembly, and a rear extinction tube arranged sequentially. The front and rear extinction tubes are used to reduce the interference of background light on the incident light.

[0011] This application also provides a polarization imaging device, which includes, from the object side to the image side, any of the aforementioned polarization adjustment devices for adjusting the polarization direction of incident light; The imaging lens group, located in front of the focal plane of the imaging detector, is used to focus light onto the focal plane of the imaging detector. An imaging detector is used to acquire image information of the object to be imaged.

[0012] In one possible implementation, the drive controller of the polarization adjustment device is further configured to control the imaging detector to acquire image information when the moving grating sheet moves to at least four specific positions within a preset travel range, and to calculate the polarization state information of the object to be imaged using the acquired image information and the position information of the specific positions.

[0013] In one possible implementation, the polarization adjustment device and the imaging lens assembly are detachably connected.

[0014] Compared with the prior art, this application has the following beneficial effects: This application reduces the influence of wavelengths other than the incident light on polarization imaging by adding a filter to the polarization adjustment device. In the polarization imaging device, by making the polarization adjustment device a detachable component from the imaging lens group, it can be quickly adapted to ordinary lenses of the same aperture type, transforming ordinary lenses into polarization imaging lenses. Compared to traditional time-division polarization imaging systems with drawbacks such as low frame rate and inability to detect in real time, this application can achieve high frame rate polarization imaging. Compared to existing imaging systems that integrate the polarization adjustment system within the polarization imaging device, this application offers convenience and versatility. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings required in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a three-dimensional structural diagram of the polarization adjustment device provided in this embodiment; Figure 2 This is a cross-sectional view of the polarization adjustment device provided in this embodiment; Figure 3 An exploded view of the polarization adjustment device provided in this embodiment; Figure 4 This is a schematic diagram of the polarization imaging device provided in this embodiment.

[0017] Icons: Polarization Imaging Device-10; Polarization Adjustment Device-100; Filter Assembly-110; Moving Grating Assembly-120; Fixed Grating Assembly-130; Polarization Assembly-140; Connection Structure-150; Filter-111; Filter Pressing Ring-112; Moving Grating Plate-121; Moving Grating Mount-122; Fixed Grating Plate-131; Fixed Grating Mount-132; Driver-161; Drive Controller-162; Front Extinction Tube-171; Rear Extinction Tube-172; Imaging Lens Group-200; Imaging Detector-300; Linear Polarizer-141; Polarizer Mount-142. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0020] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0021] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application 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, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0022] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0023] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] The inventors discovered through investigation that in existing optical imaging equipment, the polarization adjustment system is integrated into the imaging lens assembly. When the polarization adjustment system needs to be repaired, replaced, or upgraded, the operator needs to have professional optical knowledge and optical instrument operation skills, and also needs to use special tools to disassemble and assemble the polarization adjustment system. Slight carelessness may lead to damage to the components.

[0025] Furthermore, this integration method may damage the optical system of the original imaging lens assembly. During the integration of the polarization adjustment system, the imaging lens assembly may need to be adjusted to adapt to the polarization adjustment system, which may lead to problems such as increased aberrations, reduced resolution, and decreased contrast, thereby affecting image quality. When the polarization adjustment system malfunctions and needs repair or replacement, the repeated disassembly and adjustment of the original optical system will reduce the optical performance of the imaging lens assembly, affecting the stability and reliability of the optical imaging equipment.

[0026] In view of this, please refer to Figure 1 This application provides a polarization adjustment device 100, which is used to adjust the polarization direction of incident light.

[0027] Please refer to Figure 2The polarization adjustment device 100 includes a filter assembly 110, a movable grating assembly 120, a fixed grating assembly 130, a polarization assembly 140 arranged in sequence, and a connection structure 150, which is used to fix the filter assembly 110, the movable grating assembly 120, the fixed grating assembly 130 and the polarization assembly 140 in sequence.

[0028] Please refer to Figure 3 The filter assembly 110 includes a filter 111 and a filter retainer ring 112; the filter 111 is used to improve the purity of the incident light; the filter retainer ring 112 is used to fix the filter 111.

[0029] In this embodiment, by adding a filter 111 to the polarization adjustment device 100, the influence of other wavelengths besides the incident light on polarization imaging can be reduced.

[0030] It should be noted that when the filter assembly 110, the movable grating assembly 120, the fixed grating assembly 130, and the polarization assembly 140 are connected to the connecting structure 150, a combination of pins and screws can be used. This reduces the difficulty of manufacturing and improves the installation accuracy.

[0031] It should be noted that, in addition to the aforementioned connection method, other methods can be used in some other embodiments to fix the components such as the filter assembly 110, the movable grating assembly 120, the fixed grating assembly 130, and the polarization assembly 140 to the connection structure 150. No specific limitation is made here.

[0032] Please refer to Figure 3 In one possible implementation, the movable grating assembly 120 includes a movable grating sheet 121 and a movable grating base 122.

[0033] The fixed grating assembly 130 includes a fixed grating sheet 131 and a fixed grating base 132.

[0034] The surfaces of the movable grating sheet 121 and the fixed grating sheet 131 have the same univariate subwavelength periodic structure, and the grating period directions of the movable grating sheet 121 and the fixed grating sheet 131 are the same.

[0035] The polarization adjustment device 100 further includes a driver 161 and a drive controller 162. The driver 161 is used to drive the movable grating plate 121 to move so that the movable grating plate 121 and the fixed grating plate 131 are displaced relative to each other in the grating period direction. The drive controller 162 is used to control the driver 161 to drive the movable grating plate 121 to reciprocate within a preset stroke range.

[0036] In this embodiment, the moving grating plate 121 and the fixed grating plate 131 have the same period direction. The moving grating plate 121 is driven by the driver 161 and moves at high speed along the grating period direction perpendicular to the optical axis within the grating period, thereby realizing the relative offset between the moving grating plate 121 and the fixed grating plate 131 and producing a phase change effect on the incident light.

[0037] For example, when the polarization adjustment device 100 provided in this embodiment is installed on the polarization imaging device 10, images can be acquired at four or more specific positions at half the grating period, and then the final polarization image can be obtained through algorithm processing.

[0038] The polarization adjustment device 100 of this application embodiment drives the moving grating plate 121 to perform translational motion in a horizontal movement manner, which can improve the movement speed and thus improve the adjustment speed of the polarization, making it suitable for conditions that require the use of a high frame rate camera.

[0039] In one possible implementation, the filter assembly 110 includes various types of the filters 111.

[0040] In this embodiment, the filter assembly 110 may include at least one filter 111. These filters 111 may include different optical characteristics and functions. For example, a wavelength-selective filter 111 may be used to selectively transmit or absorb light according to different wavelengths; for example, a narrowband filter may only allow light within a specific small wavelength range to pass through; for example, a polarizing filter may selectively transmit light with a specific polarization direction, thereby eliminating reflected light, reducing glare, and improving image quality. By using various types of filters 111 in combination or individually, the filter assembly 110 can achieve the control and filtering of incident light for different application scenarios and optical requirements.

[0041] In one possible implementation, the filter assembly 110 is detachably connected to the connection structure 150.

[0042] In this embodiment, the filter 111 and the filter retainer 112 are detachably connected, and the filter assembly 110 and the connecting assembly are detachably connected. Different types of filters 111 have different filtering effects on light of different wavelengths. When the polarization adjustment device 100 is applied to incident light of certain specific wavelengths, it is necessary to select a filter 111 that can filter out light of other wavelengths other than the incident light wavelength. For example, for incident light with a wavelength of 1064nm, a filter 111 that can only transmit light of 1064nm wavelength should be selected.

[0043] In one possible implementation, the preset travel ensures that the moving grating 121 never deviates from the effective light-transmitting aperture of the fixed grating 131.

[0044] In this embodiment, the effective light-transmitting aperture refers to the area where light can efficiently pass through the fixed grating plate 131. When the moving grating plate 121 does not deviate from this aperture, light can pass through the polarization adjustment device 100 to the maximum extent, and the light transmission will not be reduced due to improper position of the moving grating plate 121. Once the moving grating plate 121 exceeds the effective light-transmitting aperture of the fixed grating plate 131, some light may not be able to pass through the grating plate, or diffraction may occur at the edge of the grating plate, resulting in a reduction in light transmission efficiency. By limiting the position of the moving grating plate 121 by a preset stroke, the light transmission efficiency of the entire optical path system can be maintained, ensuring that sufficient light reaches the subsequent imaging lens group 200. Thus, when the polarization adjustment device 100 provided in this embodiment is installed on the polarization imaging device 10 for use, it will not affect the light transmission of the entire optical system.

[0045] The preset travel range is determined based on actual conditions. The preset travel ensures that the moving grating plate 121 never deviates from the effective light-passing aperture of the fixed grating plate 131, without affecting the light transmission of the entire optical path system. In one possible implementation, the preset travel range is equal to half the period of the moving grating plate 121. Thus, the movement range of either the moving grating plate 121 or the fixed grating plate 131 within this preset travel range is minimized, improving the movement efficiency of either the moving grating plate 121 or the fixed grating plate 131, thereby improving the efficiency of adjusting the polarization state of the incident light.

[0046] In one possible implementation, please refer to Figure 3 The polarization adjustment device 100 includes a front extinction tube 171, a filter assembly 110, a movable grating assembly 120, a fixed grating assembly 130, a polarization assembly 140, and a rear extinction tube 172 arranged sequentially. The front extinction tube 171 and the rear extinction tube 172 are used to reduce the interference of background light on the incident light.

[0047] Since light rays from directions other than the incident light may be reflected and scattered within the polarization adjustment device 100 after entering the system, thus entering the polarization region and interfering with the polarization imaging quality, in this embodiment, a front extinction tube 171 and a rear extinction tube 172 are respectively provided at the front and rear of the polarization adjustment device 100. Specifically, the front extinction tube 171 is installed at the front end of the polarization adjustment device 100, i.e., at the entrance where the incident light enters the system. The rear extinction tube 172 is installed at the rear end of the polarization adjustment device 100, near the imaging lens group 200. Thus, when the polarization adjustment device 100 provided in this embodiment is installed on the polarization imaging device 10, most of the stray light in the optical system is blocked or absorbed, the background of the polarization imaging is cleaner, and the details and features of the incident light can be displayed more clearly, which helps to improve the resolution and accuracy of the final image.

[0048] In one possible implementation, please refer to Figure 3 The polarization component 140 includes a linear polarizer 141 and a polarizer holder 142.

[0049] It should be noted that the linear polarizer 141 and its holder are detachably connected, as are the polarization assembly 140 and the connecting assembly. Different linear polarizers 141 have different polarization effects and transmittance for different wavelengths of light. When the polarization adjustment device 100 is applied to incident light of certain specific wavelengths, a linear polarizer 141 with good polarization performance and high transmittance at that incident light wavelength needs to be selected. For example, for incident light with a wavelength of 1064 nm, a linear polarizer 141 optimized for that wavelength should be selected. Simultaneously, the linear polarizer 141 should have high transmittance to ensure sufficient light intensity passes through it, which is important for applications requiring high brightness and high contrast.

[0050] It should be noted that, in addition to the linear polarizer 141, in another embodiment, the polarization component 140 may also be a circular polarizer and a polarizer holder 142, which are not specifically limited here.

[0051] Based on the same concept, this application also provides a polarization imaging device 10, please refer to... Figure 4 The polarization adjustment device 100, which includes any one of the aforementioned components, is arranged sequentially from the object side to the image side and is used to adjust the polarization direction of the incident light.

[0052] The imaging lens group 200 is located in front of the focal plane of the imaging detector 300 and is used to focus light onto the focal plane of the imaging detector 300.

[0053] Imaging detector 300 is used to acquire image information of the object to be imaged.

[0054] In this embodiment, the aforementioned polarization adjustment device 100 is placed in front of the imaging lens group 200 and designed as a detachable component, which allows it to be quickly adapted to ordinary lenses of the same aperture type, transforming ordinary lenses into polarization imaging lenses.

[0055] Since the polarization imaging device 10 of this application embodiment is a high-speed polarization imaging device 10 based on the aforementioned polarization adjustment device 100, under the condition of using a high frame rate camera, the polarization demodulation imaging frame rate of the polarization imaging device 10 is related to the motion frequency of the driver 161 and is only limited by the camera frame rate and sensitivity. It can perform high-speed imaging and has practicality and accuracy.

[0056] In one possible implementation, the drive controller 162 of the polarization adjustment device 100 is further configured to control the imaging detector 300 to acquire image information when the movable grating plate 121 moves to at least four specific positions within a preset travel range, and to calculate the polarization state information of the object to be imaged using the acquired image information and the position information of the specific positions. The specific positions are selected according to the actual situation. When the movable grating plate 121 or the fixed grating plate 131 moves to the specific position, the imaging detector 300 performs the aforementioned preset imaging action.

[0057] In one possible implementation, the polarization adjustment device 100 and the imaging lens group 200 are detachably connected.

[0058] In this embodiment, by configuring the polarization adjustment device 100 as a component that can be detached from the imaging lens group 200, the polarization adjustment device 100 can be quickly installed and replaced to meet different usage scenarios and needs. In practical applications, it can accurately adapt to ordinary lenses of the same aperture type. By combining with ordinary lenses, it can adjust key optical parameters such as light propagation path and focusing effect, thereby turning ordinary lenses with relatively simple functions into polarization imaging lenses. Compared with traditional time-division polarization imaging systems that have the disadvantages of low frame rate and inability to detect in real time, the polarization imaging device 10 in this embodiment can achieve high frame rate polarization imaging; compared with existing imaging systems that integrate the polarization adjustment system inside the polarization imaging device, the polarization imaging device 10 in this embodiment is more convenient.

[0059] In summary, this application provides a polarization adjustment device 100 and a polarization imaging device 10. The polarization adjustment device 100 includes a filter assembly 110, a movable grating assembly 120, a fixed grating assembly 130, and a polarization assembly 140 arranged sequentially, as well as a connecting structure 150. The connecting structure 150 is used to fix the filter assembly 110, the movable grating assembly 120, the fixed grating assembly 130, and the polarization assembly 140 sequentially. The filter assembly 110 includes a filter 111 and a filter retainer ring 112. The filter 111 is used to improve the purity of the incident light. The filter retainer ring 112 is used to fix the filter 111. The polarization adjustment device 100 is used to adjust the polarization direction of the incident light. By adding a filter 111 to the polarization adjustment device 100, the influence of other wavelengths besides the incident light on polarization imaging can be reduced. In the polarization imaging device 10, by setting the polarization adjustment device 100 as a component that can be detached from the imaging lens group 200, it can be quickly adapted to ordinary lenses of the same aperture type, transforming ordinary lenses into polarization imaging lenses. Compared with traditional time-division polarization imaging systems that have the disadvantages of low frame rate and inability to detect in real time, this application can achieve high frame rate polarization imaging; compared with existing imaging systems that integrate the polarization adjustment system inside the polarization imaging device, this application has convenience and universality.

[0060] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0061] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A polarization adjustment device, characterized in that, The polarization adjustment device includes a filter component, a movable grating component, a fixed grating component, and a polarization component arranged in sequence, as well as a connecting structure, which is used to fix the filter component, the movable grating component, the fixed grating component, and the polarization component in sequence. The filtering assembly includes a filter and a filter retainer ring; the filter is used to improve the purity of the incident light; the filter retainer ring is used to fix the filter. The polarization adjustment device is used to adjust the polarization direction of the incident light.

2. The polarization adjustment device according to claim 1, characterized in that, The movable grating assembly includes a movable grating sheet and a movable grating base; The fixed grating assembly includes a fixed grating sheet and a fixed grating base; The surfaces of the movable grating sheet and the fixed grating sheet have the same univariate subwavelength periodic structure, and the grating period directions of the movable grating sheet and the fixed grating sheet are the same; The polarization adjustment device further includes a driver and a drive controller. The driver is used to drive the movable grating sheet to move so that the movable grating sheet and the fixed grating sheet are relatively displaced in the grating period direction. The drive controller is used to control the driver to drive the movable grating sheet to reciprocate within a preset stroke range.

3. The polarization adjustment device according to claim 1, characterized in that, The filtering assembly includes various types of filters.

4. The polarization adjustment device according to claim 3, characterized in that, The filter assembly is detachably connected to the connection structure.

5. The polarization adjustment device according to claim 2, characterized in that, The preset travel distance ensures that the moving grating sheet never deviates from the effective light transmission aperture of the fixed grating sheet.

6. The polarization adjustment device according to claim 5, characterized in that, The preset travel distance is equal to half the period of the moving grating sheet.

7. The polarization adjustment device according to claim 1, characterized in that, The polarization adjustment device includes a front extinction tube, the filter assembly, the movable grating assembly, the fixed grating assembly, the polarization assembly, and a rear extinction tube arranged sequentially. The front and rear extinction tubes are used to reduce the interference of background light on the incident light.

8. A polarization imaging device, characterized in that, The device comprises, from the object side to the image side, a polarization adjustment device as described in any one of claims 1-7, for adjusting the polarization direction of the incident light; The imaging lens group, located in front of the focal plane of the imaging detector, is used to focus light onto the focal plane of the imaging detector. An imaging detector is used to acquire image information of the object to be imaged.

9. The polarization imaging device according to claim 8, characterized in that, The drive controller of the polarization adjustment device is also used to control the imaging detector to acquire image information when the moving grating sheet moves to at least four specific positions within a preset travel range, and to calculate the polarization state information of the object to be imaged using the acquired image information and the position information of the specific positions.

10. The polarization imaging device according to claim 8, characterized in that, The polarization adjustment device and the imaging lens assembly are detachably connected.

Images