Relay system

Abstract

The invention provides a relay system, and relates to the technical field of optics, the relay system comprises a turn-back module and a zoom lens group, the focus of the zoom lens group coincides with the image point of the turn-back module, the turn-back module comprises a first reflector and a second reflector, the first reflector is provided with a first reflection area and a second reflection area, and the second reflector is provided with a second reflection area. A light beam enters the first reflection area of the first reflector and is reflected to the zoom lens group through the second reflector and the second reflection area of the first reflector in sequence, the focal length of the zoom lens group and the distance between the zoom lens group and the turn-back module are changed, and therefore the diameter of a light spot emitted by the zoom lens group is adjusted. And the divergent light emitted by the turn-back module is converted into parallel light through the zoom lens group to be emitted, so that the purpose of relaying is achieved. In combination with the image relay characteristic of high-precision imaging of the turn-back module and the imaging characteristic of flexible and controllable focal length of the zoom lens group, diameter-controllable turn-back light beam output is provided on the basis of ensuring the relay precision, and the requirement of precise turn-back relay is met.

Description

Technical Field

[0001] This application relates to the field of optical technologies, and more particularly to a relay system. Background Art

[0002] In the field of laser measurement, considering the complexity of the optical path and the space limitation of the mechanical structure, a relay system is often required to fold back the optical path, aiming to increase the compactness of the overall optical path and reduce the product volume of the client.

[0003] For an optical relay system, the commonly used double-mirror folding optical structure has the disadvantages of simple structure, single function, and high requirements for the quality of the incident light beam, and can no longer meet the optical relay requirements of high precision, high stability, and high beam quality in some bands. Summary of the Invention

[0004] The purpose of the embodiments of this application is to provide a relay system that outputs a beam with a controllable diameter on the basis of ensuring relay accuracy.

[0005] On the one hand, an embodiment of this application provides a relay system, including a folding module and a zoom lens group. The focal point of the zoom lens group coincides with the image point of the folding module. The folding module includes a first reflector and a second reflector. The first reflector has a first reflection area and a second reflection area. The light beam is incident on the first reflection area of the first reflector and is reflected to the zoom lens group through the second reflector and the second reflection area of the first reflector in sequence, changing the focal length of the zoom lens group and the distance between the zoom lens group and the folding module to adjust the diameter of the light spot emitted by the zoom lens group.

[0006] Optionally, the first reflection area and the second reflection area are respectively located at both ends of the first reflector in the direction perpendicular to the optical axis, and the second reflector is located between the first reflection area and the second reflection area of the first reflector.

[0007] Optionally, the first reflector includes a concave spherical mirror, and the second reflector includes a convex spherical mirror.

[0008] Optionally, the folding module further includes a light homogenizing component. The light homogenizing component includes a micro-nano optical element. After the light beam passes through the micro-nano optical element, it is incident on the first reflection area of the first reflector. The micro-nano optical element is used to make the light beam incident on the first reflector at a preset divergence angle.

[0009] Optionally, the light homogenizing component further includes a lens disposed between the micro-nano optical element and the first reflector.

[0010] Optionally, the lens is a positive lens.

[0011] Optionally, a diffuser is further disposed between the lens and the first reflector, and the diffuser is rotatably disposed in the plane perpendicular to the optical axis.

[0012] Optionally, the diffuser is connected to a motor, and the diffuser is driven to rotate by the motor.

[0013] Optionally, an aperture stop is further disposed between the diffuser and the first reflector.

[0014] Optionally, the micro-nano optical element, the lens, the diffuser, and the aperture stop are correspondingly disposed on one side of the first reflection area of the first reflector along the optical axis, and the zoom lens group is correspondingly disposed on one side of the second reflection area of the first reflector.

[0015] The relay system provided by the embodiment of the present application includes a folding module and a zoom lens group. The focal point of the zoom lens group coincides with the image point of the folding module. The folding module includes a first reflector and a second reflector. The first reflector has a first reflection area and a second reflection area. The light beam is incident on the first reflection area of the first reflector and is reflected to the zoom lens group through the second reflector and the second reflection area of the first reflector in sequence, so as to change the focal length of the zoom lens group and the distance between the zoom lens group and the folding module, so as to adjust the diameter of the light spot emitted by the zoom lens group.

[0016] The zoom lens group is placed at a position where its focal point coincides with the image point emitted by the folding module, so as to convert the divergent light emitted by the folding module into parallel light through the zoom lens group and achieve the purpose of relay. Moreover, the diameter of the output light spot can also be adjusted by adjusting the focal length and position of the zoom lens group, so as to achieve the purpose of optical relay and adjusting the size of the output light spot. The present application combines the image relay characteristics of high-precision imaging of the folding module and the imaging characteristics of flexible controllability of the focal length of the zoom lens group to provide an output of a folding light beam with a controllable diameter on the basis of ensuring the relay accuracy, meeting the precise folding relay requirements in a wider range of application scenarios. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0018] Figure 1 It is a schematic structural diagram of the relay system provided by the embodiment of the present application.

[0019] Reference numerals: 10 - first reflector; 101 - first reflection area; 102 - second reflection area; 11 - second reflector; 12 - micro-nano optical element; 13 - lens; 14 - diffuser; 15 - motor; 16 - aperture stop; 20 - zoom lens group; S - optical axis; F - plane direction. Detailed Description

[0020] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application.

[0021] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this application is usually placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application. In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0022] It should also be noted that unless otherwise clearly specified and defined, the terms "set", "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0023] In the field of laser measurement optical relay technology, the currently used methods are mainly as follows:

[0024] First, use plane mirrors with opposite included angles between two sides to relay the light beam. However, since the two plane mirrors are relatively independent, during the alignment process, the height and deflection angles of the two mirrors need to be adjusted separately. The alignment is more cumbersome and the accuracy is poor, which does not meet the high-precision requirements.

[0025] Second, use a triangular prism to relay the light beam. However, since the volume of the triangular prism is usually large and it occupies more space, it is not conducive to the miniaturization of the system. In addition, due to the dispersion effect of the prism, it will have an adverse impact on the imaging quality of a broadband light source.

[0026] Third, use an optical fiber relay system to relay the light beam. In this case, since the propagation speeds of different modes of light in multimode optical fibers are different, it may cause dispersion of signal transmission. In addition, the end face of the optical fiber connector may introduce reflection loss, affecting the optical coupling efficiency and the overall performance of the system.

[0027] In view of this, please refer to Figure 1As shown in the figure, an embodiment of the present application provides a relay system, including: a folding module and a zoom lens group 20. The focal point of the zoom lens group 20 coincides with the image point of the folding module. The folding module includes a first reflector 10 and a second reflector 11. The first reflector 10 has a first reflection area 101 and a second reflection area 102. A light beam is incident on the first reflection area 101 of the first reflector 10, and is reflected by the second reflector 11 and the second reflection area 102 of the first reflector 10 in sequence and then reaches the zoom lens group 20. The focal length of the zoom lens group 20 is variable and its position is adjustable. By changing the focal length of the zoom lens group 20 and the distance between the zoom lens group 20 and the folding module along the optical axis S direction, the diameter of the light spot emitted by the zoom lens group 20 is adjusted.

[0028] The folding module is used to accurately transmit the light beam from one position to another position. In the present application, the folding module includes a first reflector 10 and a second reflector 11. The first reflector 10 has two reflection areas, namely a first reflection area 101 and a second reflection area 102. The first reflection area 101 of the first reflector 10 is arranged to reflect the light beam towards the second reflection area 102 of the first reflector 10 via the second reflector 11.

[0029] In some embodiments, the first reflector 10 may include a mirror surface, and the second reflector 11 may include a mirror surface. Further, the first reflector 10 may include a concave spherical mirror, and the second reflector 11 may include a convex spherical mirror.

[0030] In addition, a zoom lens group 20 is further included. The zoom lens group 20 is placed at a position where its focal point coincides with the image point emitted by the folding module, so as to convert the divergent light emitted by the folding module into parallel light through the zoom lens group 20 and achieve the purpose of relay. Moreover, the diameter of the output light spot can be adjusted by adjusting the focal length and position of the zoom lens group 20 for the emitted light beam, so as to achieve the purpose of optical relay and adjusting the size of the output light spot.

[0031] Specifically, as Figure 1 shown, the first reflection area 101 and the second reflection area 102 are respectively located at both ends of the first reflector 10 perpendicular to the optical axis S direction, while the second reflector 11 is located between the first reflection area 101 and the second reflection area 102 of the first reflector 10. In this way, the light beam is first incident on the first reflection area 101. The first reflection area 101 reflects the light beam towards the second reflector 11. The second reflector 11 then reflects the light beam towards the second reflection area 102. Finally, the second reflection area 102 reflects the light beam towards the zoom lens group 20, and the light spot is emitted by the zoom lens group 20.

[0032] Due to the concentric structure characteristics of the first reflection area 101 and the second reflection area 102 of the first reflector 10 in the folding module, which have rotational symmetry (in the plane direction F perpendicular to the optical axis S, the first reflection area 101 and the second reflection area 102 are rotationally symmetric), spherical aberration, coma, and distortion can be automatically corrected. It has a high-precision optical relay function with unit magnification and has broad application prospects in the field of laser measurement.

[0033] The focal length of the zoom lens group 20 is variable and its position is adjustable. Utilizing the characteristic that the focal length of the zoom lens group 20 is variable under different voltages, the focal length of the zoom lens group 20 is changed by controlling the voltage. Combining with a high-precision mechanical translation stage or other moving platforms to control the position movement of the zoom lens group 20, the distance between the zoom lens group 20 and the folding module is changed to ensure that the focal points of the zoom lens group 20 with different focal lengths coincide with the image-side focal point of the folding module. With the relay system of the present application, the adjustment of the diameter of the outgoing beam can meet the diameter adjustment requirements from 1 times to 4 times.

[0034] In some embodiments, the zoom lens group 20 can be a single lens, for example, it can be a liquid crystal lens. In other embodiments, the zoom lens group 20 can also be a zoom lens group composed of multiple lenses, which will not be elaborated here.

[0035] The present application provides high-quality beam adjustment during the relay process, which can adjust the intensity distribution and wavefront morphology of the beam, etc.; it can provide an accurate beam relay process with high precision, low aberration, and high energy transmission efficiency; for the function of adjusting the diameter of the outgoing beam, different gear linear controls can be achieved through the programming of the controller.

[0036] On this basis, the folding module further includes a beam homogenizing component. The beam homogenizing component includes a micro-nano optical element 12. After the beam passes through the micro-nano optical element 12, it enters the first reflection area 101 of the first reflector 10. The micro-nano optical element 12 is used to make the beam enter the first reflector 10 at a preset divergence angle.

[0037] The micro-nano optical element 12 can be a diffractive optical element DOE. Utilizing the characteristics of the diffractive optical element, through the principle of optical diffraction, without introducing spherical aberration, the incident light spot is homogenized or the wavefront is adjusted. The folding module performs high-precision folding optical relay on the beam that has undergone optical diffraction regulation after exiting from the DOE.

[0038] Of course, the beam homogenization of the micro-nano optical element 12 is not limited to the diffraction beam adjustment performed by the diffractive optical element, and can also be achieved by other means. For example, a diffuser and a microlens array (MLA), etc.

[0039] The beam homogenizing component further includes a lens 13 disposed between the micro-nano optical element 12 and the first reflector 10. The lens 13 is a positive lens, for example, the lens 13 is a biconvex lens.

[0040] A diffuser 14 is also provided between the lens 13 and the first reflector 10. The diffuser 14 can be a frosted glass. The diffuser 14 is rotatably arranged in the plane direction F perpendicular to the optical axis S, and when rotating, the motor 15 connected to the diffuser 14 drives the diffuser 14 to rotate.

[0041] An aperture stop 16 is also provided between the diffuser 14 and the first reflector 10, so that the light beam is incident on the first reflector 10 through the aperture stop 16. Among them, the aperture size of the aperture stop 16 is adjustable.

[0042] The purposes of arranging the above-mentioned micro-nano optical element 12, lens 13, diffuser 14 and aperture stop 16 are all to homogenize the light, so that the light beam can be evenly incident on the first reflector 10.

[0043] The micro-nano optical element 12, lens 13, diffuser 14 and aperture stop 16 are correspondingly arranged on one side of the first reflection area 101 of the first reflector 10 along the optical axis S, and the zoom lens group 20 is correspondingly arranged on one side of the second reflection area 102 of the first reflector 10, so that the light beam passes through the micro-nano optical element 12, lens 13, diffuser 14, aperture stop 16, first reflection area 101, second reflector 11, second reflection area 102 and zoom lens group 20 in sequence and exits.

[0044] Exemplarily, the light beam needs to be collimated before entering the micro-nano optical element 12. Taking the light beam with a wavelength of 532nm as an example, the collimated 532nm light beam first passes through the DOE. The DOE mainly modulates its spot shape, energy and wavefront distribution, and makes the light beam enter the lens 13 at a determined preset divergence angle. The divergent light beam is Fourier frequency-transformed by the positive lens 13 and then enters the rotating diffuser 14 in parallel and diverges. The angle restricted by the aperture stop 16 with an adjustable aperture is the object-side cone angle of the folding module.

[0045] After passing through the folding module, the light beam emits a light beam with a certain image-side cone angle, and finally diverges into parallel light through the zoom lens group 20, achieving the purpose of relay.

[0046] This application is not limited to being applied to the above-mentioned 532nm wavelength, not limited to a single wavelength, and can include a free combination of wavelengths within different visible light ranges.

[0047] By combining the image relay characteristics of the 1:1 high-precision imaging of the folding module and the imaging characteristics of the flexible and controllable focal length of the zoom lens group 20, this application provides an output of a folding light beam with a controllable diameter on the basis of ensuring the relay accuracy, meeting the precise folding relay requirements in a wider range of application scenarios.

[0048] The above are only examples of the present application and are not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of protection of the present application.

Claims

1. A relay system, characterized in that, Comprising: A folding module and a zoom lens group, the focal point of the zoom lens group coincides with the image point of the folding module, the folding module includes a first reflector and a second reflector, the first reflector has a first reflection area and a second reflection area, a light beam enters the first reflection area of the first reflector and is reflected by the second reflector and the second reflection area of the first reflector in sequence to the zoom lens group, changing the focal length of the zoom lens group and the distance between the zoom lens group and the folding module to adjust the diameter of the light spot emitted by the zoom lens group.

2. The relay system according to claim 1, wherein The first reflection area and the second reflection area are respectively located at both ends of the first reflector in the direction perpendicular to the optical axis, and the second reflector is located between the first reflection area and the second reflection area of the first reflector.

3. The relay system according to claim 1, wherein The first reflector includes a concave spherical mirror, and the second reflector includes a convex spherical mirror.

4. The relay system according to any one of claims 1 to 3, characterized in that The folding module further includes a light homogenizing component, the light homogenizing component includes a micro-nano optical element, after the light beam passes through the micro-nano optical element, it enters the first reflection area of the first reflector, and the micro-nano optical element is used to make the light beam enter the first reflector at a preset divergence angle.

5. The relay system according to claim 4, wherein The light homogenizing component further includes a lens disposed between the micro-nano optical element and the first reflector.

6. The relay system according to claim 5, wherein The lens is a positive lens.

7. The relay system according to claim 5, wherein A diffuser is further disposed between the lens and the first reflector, and the diffuser is rotatably disposed in the plane direction perpendicular to the optical axis.

8. The relay system according to claim 7, wherein The diffuser is connected to a motor, and the diffuser is driven to rotate by the motor.

9. The relay system according to claim 7, characterized in that, An aperture stop is further disposed between the diffuser and the first reflector.

10. The relay system according to claim 9, wherein, The micro-nano optical element, the lens, the diffuser and the aperture stop are correspondingly disposed on one side of the first reflection area of the first reflector along the optical axis, and the zoom lens group is correspondingly disposed on one side of the second reflection area of the first reflector.

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