Stray light suppression device based on polarization-delay combined modulation
By using a polarization-delay modulation method, which combines polarizers and waveplates, the problem of stray light suppression in complex optical path environments is solved, thereby improving the image quality and performance of the optical system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TIANJIN RES INST FOR WATER TRANSPORT ENG M O T
- Filing Date
- 2025-04-16
- Publication Date
- 2026-05-26
AI Technical Summary
Existing technologies are insufficient to effectively suppress stray light of different angles and polarization states in complex optical path environments, which affects the resolution, sensitivity, and image quality of optical systems.
A polarization-delay modulation method is adopted, which uses a combination of polarizers and waveplates to separate stray light from target light by taking advantage of the difference in the polarization state of light. Combined with a polarization beam splitter and absorption device, adaptive stray light suppression is achieved.
It significantly improves the image contrast and sharpness of optical systems, reduces noise, enhances resolution and sensitivity, adapts to the needs of different optical systems, and achieves adaptive stray light suppression.
Smart Images
Figure CN224287259U_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of optical equipment technology, and in particular relates to a stray light suppression device based on polarization-delay combined modulation. Background Technology
[0002] In many optical systems, such as astronomical observation instruments, microscopes, laser processing equipment, and optical imaging systems, stray light has always been one of the key issues affecting system performance. Stray light reduces image contrast and sharpness, increases noise, interferes with the accurate detection and analysis of target signals, and thus limits the key performance indicators of optical systems, such as resolution and sensitivity.
[0003] Traditional stray light suppression methods often employ techniques such as light shields, apertures, and filters. While these methods can reduce stray light to some extent, their effectiveness is limited in suppressing stray light at specific angles and polarization states in complex optical path environments, making them insufficient for the demands of high-precision optical applications. For example, in certain precision optical measurement scenarios, even after conventional processing, weak stray light can still increase measurement errors; in the field of optical imaging, stray light can cause defects such as halos and blurring, affecting image quality. Therefore, a more efficient and precise stray light suppression device is urgently needed to overcome the shortcomings of existing technologies. Utility Model Content
[0004] In view of this, the present invention aims to propose a stray light suppression device based on polarization-delay combined modulation, which can effectively suppress stray light and improve the performance of the optical system by cleverly utilizing the principles of polarization and delay for combined modulation.
[0005] To achieve the above objectives, the technical solution of this utility model is implemented as follows:
[0006] A stray light suppression device based on polarization-delay combined modulation includes a polarization modulation module, a delay modulation module, and an optical separation module;
[0007] The polarization modulation module includes at least one polarizer, which is used to select the polarization state of the incident light and convert natural light or mixed polarized light into linearly polarized light with a specific polarization direction.
[0008] The delay modulation module is disposed on the light emission path of the polarization modulation module. The delay modulation module includes at least one waveplate, which is used to introduce a specific phase delay into the polarization-modulated light, change the polarization state of the light, and make the stray light and the target light have different polarization characteristics.
[0009] The optical separation module is located on the light emission path of the delay modulation module. Based on the polarization difference of light, the optical separation module separates stray light from target light, allowing target light to pass through while blocking stray light.
[0010] Furthermore, the polarization modulation module also includes a polarizer rotation mechanism, which includes a rotating base, a lifting cylinder, a support plate, and a rotating plate. The lifting cylinder and the support plate are both installed on the rotating base, and the lifting cylinder is located on one side of the support plate. The extension rod of the lifting cylinder and the top of the support plate are movably connected to the bottom of the rotating plate through a connecting shaft. A polarizer is installed on the top of the rotating plate.
[0011] Furthermore, the top of the support plate is provided with an integrally formed support plate, the upper end of which is connected to the connecting shaft.
[0012] Furthermore, the bottom sides of the rotating plate are provided with integrally formed folded edges, and two sliding grooves are symmetrically opened on the two folded edges, in which the connecting shaft slides.
[0013] Furthermore, the waveplates in the delay modulation module include waveplates with different delay amounts.
[0014] Furthermore, the optical separation module employs a polarization beam splitter, which reflects stray light with a specific polarization state to the absorption device, while simultaneously allowing the target light to be transmitted along the original optical path or a predetermined optical path to subsequent optical elements.
[0015] Furthermore, the absorption device is a cavity structure coated with a light-absorbing material, and the light-absorbing material on the inner surface of the cavity is used to efficiently absorb the reflected stray light.
[0016] Furthermore, it also includes a light intensity monitoring module and a control system. The light intensity monitoring module is set on the transmission path of the target light and is used to monitor the light intensity of the target light after stray light suppression in real time. The light intensity data is fed back to the control system, and the control system adjusts the parameters of the polarization modulation module and the delay modulation module according to the feedback information to achieve adaptive stray light suppression.
[0017] Furthermore, the control system is connected to the polarizer rotation mechanism so as to adjust the polarization state according to the feedback from the light intensity monitoring module.
[0018] Compared with existing technologies, the stray light suppression device based on polarization-delay combined modulation described in this invention has the following advantages:
[0019] (1) The stray light suppression device based on polarization-delay combination modulation described in this utility model precisely processes the difference in polarization characteristics between stray light and target light. Compared with traditional stray light suppression methods, it can more effectively suppress stray light of different angles and polarization states in complex optical path environments, significantly improve the image contrast and clarity of the optical system, reduce noise, and enhance the resolution and sensitivity of the system.
[0020] (2) The stray light suppression device based on polarization-delay combination modulation described in this utility model, by setting a polarizer rotation mechanism and a replaceable waveplate design, enables the device to flexibly adapt to various different incident light conditions and optical system requirements. It has strong versatility and can be widely used in various high-precision optical instruments and equipment.
[0021] (3) The stray light suppression device based on polarization-delay combination modulation described in this utility model achieves adaptive stray light suppression through the cooperation of the light intensity monitoring module and the control system. It can automatically adjust the device parameters in real time according to the changes in light intensity in the optical path, ensuring that a good stray light suppression effect is always maintained under different working conditions, and further optimizing the performance of the optical system. Attached Figure Description
[0022] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings:
[0023] Figure 1 This is a schematic diagram of the overall structural principle of the present utility model embodiment;
[0024] Figure 2 This is a schematic diagram of the polarizer rotation mechanism described in an embodiment of the present invention;
[0025] Figure 3 This is a schematic diagram showing the connection between the support plate and the rotating plate according to an embodiment of the present utility model;
[0026] Figure 4 This is a bottom view of the rotating plate described in an embodiment of the present invention.
[0027] Explanation of reference numerals in the attached figures:
[0028] 1. Polarization modulation module; 11. Polarizer; 12. Polarizer rotation mechanism; 121. Rotating base; 122. Lifting cylinder; 123. Support plate; 1231. Support plate; 124. Rotating plate; 1241. Folded edge; 1242. Sliding groove; 2. Delay modulation module; 21. Waveplate; 3. Light separation module; 31. Polarization beam splitter; 4. Absorption device; 5. Light intensity monitoring module; 6. Control system. Detailed Implementation
[0029] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.
[0030] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model 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 of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0031] In the description of this utility model, 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, 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 will understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0032] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0033] like Figures 1 to 4 As shown, a stray light suppression device based on polarization-delay combined modulation includes:
[0034] The polarization modulation module 1 includes at least one polarizer 11, which is used to select the polarization state of incident light and convert natural light or mixed polarized light into linearly polarized light with a specific polarization direction.
[0035] The delay modulation module 2 is disposed on the light emission path of the polarization modulation module 1. The delay modulation module 2 includes at least one waveplate 21. The waveplate 21 is used to introduce a specific phase delay into the polarization-modulated light, change the polarization state of the light, and make the stray light and the target light have different polarization characteristics.
[0036] The light separation module 3 is disposed on the light emission path of the delay modulation module 2. The light separation module 3 separates stray light from target light based on the polarization difference of light, allowing the target light to pass through while blocking stray light.
[0037] In a preferred embodiment of this utility model, the polarization modulation module 1 further includes a polarizer rotation mechanism 12. The polarizer rotation mechanism 12 includes a rotating base 121, a lifting cylinder 122, a support plate 123, and a rotating plate 124. The lifting cylinder 122 and the support plate 123 are both mounted on the rotating base 121, with the lifting cylinder 122 located on one side of the support plate 123. The telescopic rod of the lifting cylinder 122 and the top of the support plate 123 are movably connected to the bottom of the rotating plate 124 via connecting shafts. A polarizer 11 is mounted on the top of the rotating plate 124. The top of the support plate 123 has an integrally formed structure. The support plate 1231 is connected to the connecting shaft at its upper end; the bottom sides of the rotating plate 124 are provided with integrally formed folded edges 1241, and the two folded edges 1241 are symmetrically provided with two sliding grooves 1242, and the connecting shaft slides in the sliding grooves 1242; the connecting shaft can slide in the sliding grooves 1242. The purpose of the sliding grooves 1242 is to avoid interference with the lifting cylinder 122's telescopic rod lifting and lowering to drive the rotating plate 124 to rotate. The polarizer rotation mechanism 12 is connected to the polarizer 11 and is used to precisely adjust the polarization direction of the polarizer 11 to adapt to the polarization characteristics requirements of different incident lights.
[0038] In a preferred embodiment of this utility model, the waveplate 21 in the delay modulation module 2 is replaceable, including waveplates 21 with different delay amounts. A waveplate 21 with a suitable delay amount can be selected and installed according to the actual stray light situation and the requirements of the optical system.
[0039] In a preferred embodiment of this utility model, the light separation module 3 employs a polarization beam splitter 31, which reflects stray light with a specific polarization state to the absorption device 4, while simultaneously allowing the target light to be transmitted to subsequent optical elements along the original optical path or a predetermined optical path.
[0040] In a preferred embodiment of this utility model, the absorption device 4 is a cavity structure coated with a light-absorbing material. The light-absorbing material on the inner surface of the cavity is used to efficiently absorb the reflected stray light and prevent the stray light from being reflected back into the optical path.
[0041] In a preferred embodiment of this utility model, the stray light suppression device based on polarization-delay combined modulation further includes a light intensity monitoring module 5. The light intensity monitoring module 5 is set on the transmission path of the target light and is used to monitor the light intensity of the target light after stray light suppression in real time. The light intensity data is fed back to the control system 6. The control system 6 adjusts the parameters of the polarization modulation module 1 and the delay modulation module 2 according to the feedback information to achieve adaptive stray light suppression.
[0042] In a preferred embodiment of this utility model, the control system 6 is electrically connected to the polarizer rotation mechanism 12 so as to accurately control the polarization state adjustment based on the feedback from the light intensity monitoring module 5.
[0043] Beneficial effects:
[0044] This invention utilizes the principle of polarization-delay combined modulation to precisely process the difference in polarization characteristics between stray light and target light. Compared with traditional stray light suppression methods, it can more effectively suppress stray light of different angles and polarization states in complex optical path environments, significantly improve the image contrast and clarity of the optical system, reduce noise, and enhance the system's resolution and sensitivity.
[0045] By incorporating a polarizer rotation mechanism and a replaceable waveplate design, the device can flexibly adapt to various incident light conditions and optical system requirements, making it highly versatile and widely applicable to various high-precision optical instruments and equipment.
[0046] The coordination between the light intensity monitoring module and the control system enables adaptive stray light suppression. It can automatically adjust the device parameters in real time according to the changes in light intensity in the optical path, ensuring that a good stray light suppression effect is maintained under different operating conditions, and further optimizing the performance of the optical system.
[0047] Example 1
[0048] It mainly consists of a polarization modulation module 1, a delay modulation module 2, an optical separation module 3, an absorption device 4, a light intensity monitoring module 5, and a control system 6.
[0049] The polarization modulation module 1 is the first line of defense in the suppression device. Its core component, the polarizer 11, performs preliminary processing on the incident light. When natural light or mixed polarized light containing stray light is incident on the polarizer 11, only the light component vibrating along the transmission axis of the polarizer can pass through, thus converting the incident light into linearly polarized light with a specific polarization direction. To accommodate the polarization characteristics of different incident lights, the polarization modulation module 1 is also equipped with a polarizer rotation mechanism 12. The operator can precisely control the polarizer rotation mechanism 12 through the control system 6 to rotate the polarizer 11 to a suitable angle to obtain the best polarization state selection effect.
[0050] After polarization modulation, the light enters the delay modulation module 2, where waveplates 21 introduce a specific phase delay. Different types and thicknesses of waveplates 21 can produce different amounts of phase delay, thereby changing the polarization state of the light. The waveplates 21 in this device are replaceable. Based on the analysis of the polarization characteristics of stray light in the actual optical path and the requirements of the optical system for stray light suppression, a waveplate 21 with a suitable delay amount can be selected for installation. For example, in some astronomical observation optical systems where the stray light polarization state is relatively complex, it may be necessary to use a combination of multi-level waveplates with precise control of the delay amount to achieve fine polarization state adjustment; while in general microscope optical paths, a single-level standard waveplate pre-configured according to common stray light conditions is sufficient to meet the requirements.
[0051] The light separation module 3 is positioned immediately following the delay modulation module 2. In this embodiment, the light separation module 3 employs a polarization beam splitter 31. Since the stray light after polarization modulation and delay modulation differs significantly in polarization characteristics from the target light, the polarization beam splitter 31 can utilize this difference to separate the two. The stray light is reflected by the polarization beam splitter 31 to the absorption device 4, while the target light is transmitted along the original optical path or a predetermined optical path according to the optical system design to subsequent optical elements, ensuring that the target light enters the subsequent optical processing without interference from stray light.
[0052] The absorption device 4 is a cavity structure coated with light-absorbing material. When the polarization beam splitter 31 reflects stray light into the absorption device 4, the light-absorbing material on the inner surface of the cavity can efficiently absorb the stray light, preventing the stray light from escaping into the optical path again after multiple reflections in the cavity, and completely eliminating the potential impact of stray light on the optical system.
[0053] The light intensity monitoring module 5 is positioned along the transmission path of the target light to monitor its intensity in real time after stray light suppression processing. The light intensity monitoring module 5 transmits the collected light intensity data to the control system 6, which has a built-in preset light intensity threshold. If the light intensity data fed back by the light intensity monitoring module 5 exceeds the normal fluctuation range, it indicates poor stray light suppression, possibly due to changes in the optical path environment or aging of optical components. In this case, the control system 6 quickly adjusts the polarizer rotation mechanism 1 in the polarization modulation module 1 based on the feedback information to achieve efficient suppression of stray light, ensuring the optical system always operates at its optimal state. The control system 6 can be an existing industrial computer or PLC.
[0054] In practical applications, such as in laser precision machining equipment, the laser beam serves as the target light. During processing, due to the complex environment surrounding the optical path, a large amount of stray light is generated by reflection and scattering. The stray light suppression device of this invention is installed in the optical path. Through the aforementioned series of polarization-delay modulation, light separation, and adaptive adjustment processes, it effectively filters out stray light, enabling the laser to be precisely focused on the workpiece, thus improving processing accuracy and quality. Furthermore, in high-end optical imaging systems such as aerospace remote sensing cameras, this device can significantly improve image clarity and contrast, providing more reliable image data support for tasks such as ground observation and target recognition.
[0055] In summary, the stray light suppression device based on polarization-delay modulation of this invention has a reasonable structural design and complete functions. Through the synergistic effect of multiple technical means, it provides an innovative and efficient solution to the stray light problem in optical systems, and has broad application prospects and significant practical value.
[0056] It should be noted that this application does not improve the control program, and the control program and electrical components involved are all prior art.
[0057] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A device for stray light suppression based on polarization-delay combined modulation, characterized in that: It includes a polarization modulation module (1), a delay modulation module (2), and an optical separation module (3); The polarization modulation module (1) includes at least one polarizer (11), which is used to select the polarization state of the incident light and convert natural light or mixed polarized light into linearly polarized light with a specific polarization direction. The delay modulation module (2) is disposed on the light emission path of the polarization modulation module (1). The delay modulation module (2) includes at least one waveplate (21). The waveplate (21) is used to introduce a specific phase delay into the polarization-modulated light, change the polarization state of the light, and make the stray light and the target light have different polarization characteristics. The light separation module (3) is located on the light emission path of the delay modulation module (2). Based on the polarization difference of light, the light separation module (3) separates stray light from target light, allowing target light to pass through while blocking stray light.
2. The polarization-delay-combined modulation based stray light suppression device according to claim 1, wherein: The polarization modulation module (1) further includes a polarizer (11) rotation mechanism. The polarizer (11) rotation mechanism includes a rotating base (121), a lifting cylinder (122), a support plate (123), and a rotating plate (124). The lifting cylinder (122) and the support plate (123) are both installed on the rotating base (121), and the lifting cylinder (122) is located on one side of the support plate (123). The telescopic rod of the lifting cylinder (122) and the top of the support plate (123) are movably connected to the bottom of the rotating plate (124) through a connecting shaft. The polarizer (11) is installed on the top of the rotating plate (124).
3. The polarization-delay-combined modulation based stray light suppression device according to claim 2, characterized in that: The top of the support plate (123) is provided with an integrally formed support plate (1231), and the upper end of the support plate (1231) is connected to the connecting shaft.
4. The polarization-delay-combined modulation based stray light suppression device according to claim 2, characterized in that: The rotating plate (124) has integrally formed folded edges (1241) on both sides of its bottom, and two sliding grooves (1242) are symmetrically opened on the two folded edges (1241), and the connecting shaft slides in the sliding grooves (1242).
5. The polarization-delay-combined modulation based stray light suppression device according to claim 1, wherein: The waveplates (21) in the delay modulation module (2) include waveplates (21) with different delay amounts.
6. The stray light suppression device based on polarization-delay combined modulation according to claim 1, characterized in that: The optical separation module (3) employs a polarization beam splitter (31), which reflects stray light with a specific polarization state to the absorption device (4) while simultaneously transmitting the target light along the original optical path or a predetermined optical path to subsequent optical elements.
7. The polarization-delay-combined modulation based stray light suppression device according to claim 6, characterized in that: The absorption device (4) is a cavity structure coated with light-absorbing material. The light-absorbing material on the inner surface of the cavity is used to efficiently absorb the stray light reflected from the cavity.
8. The polarization-delay-combined modulation based stray light suppression device according to claim 1, wherein: It also includes a light intensity monitoring module (5) and a control system (6). The light intensity monitoring module (5) is set on the transmission path of the target light and is used to monitor the light intensity of the target light after stray light suppression in real time. The light intensity data is fed back to the control system (6). The control system (6) adjusts the parameters of the polarization modulation module (1) and the delay modulation module (2) according to the feedback information to achieve adaptive stray light suppression.
9. The polarization-delay-combination-modulation-based stray light suppression device according to claim 8, characterized in that: The control system (6) is connected to the polarizer (11) rotation mechanism so as to adjust the polarization state according to the feedback control of the light intensity monitoring module (5).