CN219936218U - Laser beam expanding collimation structure and scanning imaging system - Google Patents

Abstract

The utility model provides a laser beam expanding collimation structure and a scanning imaging system. The laser beam expanding and collimating structure comprises a first part, a second part and a third part which are sequentially arranged along the transmission direction of the optical path, wherein the first part comprises an incident surface and a first reflecting surface, the second part comprises at least one reflecting surface, the third part comprises an emergent surface, the incident surface and the first reflecting surface are oppositely arranged, and at least one of the incident surface and the first reflecting surface is non-planar. The utility model solves the problems that the laser beam expansion collimation structure in the prior art has miniaturization, large beam expansion multiplying power and large scanning visual field are difficult to be simultaneously compatible.

Description

Laser beam expanding collimation structure and scanning imaging system

Technical Field

The utility model relates to the technical field of imaging equipment, in particular to a laser beam expanding and collimating structure and a scanning imaging system.

Background

The scanning imaging system based on MEMS is a novel imaging technology, and becomes a very promising projection display scheme for realizing the lightness of AR head-mounted equipment due to the advantages of small volume, high brightness and the like, however, the beam diameter is not very large due to the limitation of the size of MEMS, and the phenomenon of speckles can appear on an imaging picture after the imaging picture passes through an AR waveguide structure. Therefore, a beam-expanding relay system is required, however, the volume of the LBS-based AR projection engine is difficult to be made small due to the existence of the pupil-expanding system.

Common laser beam expansion collimation structures include transmission type and reflection type. Since the reflective type is simpler and more compact than the transmissive type structure, the laser beam expanding and collimating structure currently applied to the MEMS scanning imaging (LBS) based AR projection optical machine is mainly the reflective type structure. However, the volume is positively correlated with the beam expansion ratio and the scan field of view, and it is difficult to realize a large beam expansion ratio and a large scan field of view in a small volume.

That is, the laser beam expansion and collimation structure in the prior art has the problems that miniaturization, large beam expansion multiplying power and large scanning visual field are difficult to be simultaneously combined.

Disclosure of Invention

The utility model mainly aims to provide a laser beam expanding and collimating structure and a scanning imaging system, which are used for solving the problems that the laser beam expanding and collimating structure in the prior art is miniaturized, has large beam expanding multiplying power and has large scanning visual field and is difficult to simultaneously consider.

In order to achieve the above object, according to one aspect of the present utility model, there is provided a laser beam expanding and collimating structure including a first portion, a second portion, and a third portion sequentially arranged along a transmission direction of an optical path, the first portion including an incident surface and a first reflecting surface, the second portion including at least one reflecting surface, the third portion including an exit surface, the incident surface and the first reflecting surface being disposed opposite to each other, and at least one of the incident surface and the first reflecting surface being non-planar.

Further, the third part further comprises a fourth reflecting surface, the fourth reflecting surface is opposite to the emergent surface, and the light entering the laser beam expanding and collimating structure from the incident surface is reflected by the first reflecting surface, at least one reflecting surface of the second part and the fourth reflecting surface in sequence and then exits from the emergent surface.

Further, the second part comprises a second reflecting surface and a third reflecting surface, the second reflecting surface is opposite to the third reflecting surface, the incident surface, the second reflecting surface and the fourth reflecting surface are sequentially connected, and the first reflecting surface, the third reflecting surface and the emergent surface are sequentially connected.

Further, the distance between the incident surface and the first reflecting surface gradually increases in a direction approaching the exit surface, and the distance between the fourth reflecting surface and the exit surface gradually decreases in a direction departing from the incident surface.

Further, the laser beam expansion collimation structure further comprises an antireflection film and an antireflection film, wherein the antireflection film is arranged on at least one of the incident surface and the emergent surface, and the antireflection film is arranged on at least one of the first reflecting surface, the second reflecting surface, the third reflecting surface and the fourth reflecting surface.

Further, at least the first reflective surface and the fourth reflective surface are non-planar.

Further, the incident surface is a plane or a non-plane, and when the incident surface is a non-plane, the incident surface is convexly arranged in a direction away from the first reflecting surface.

Further, the non-planar surface includes one of a spherical surface, an aspherical surface, and a free-form surface, and the incident surface and the first reflection surface are both non-planar surfaces.

Further, the second reflecting surface and the third reflecting surface are both plane surfaces, and the second reflecting surface is parallel to the third reflecting surface.

Further, the fourth reflecting surface is non-planar, and the emergent surface is planar; or the fourth reflecting surface and the emergent surface are non-planar.

Further, when the exit face is non-planar, the exit face is formed by at least two connectively converging lenses.

Further, the refractive index of the laser beam expansion collimation structure is more than or equal to 1 and less than or equal to 5.

According to another aspect of the present utility model, there is provided a scanning imaging system comprising: the MEMS galvanometer is used for emitting light; the laser beam expanding and collimating structure is positioned on the light emitting side of the MEMS galvanometer, and the MEMS galvanometer corresponds to the incident surface of the laser beam expanding and collimating structure.

By applying the technical scheme of the utility model, the laser beam expansion collimation structure comprises a first part, a second part and a third part which are sequentially arranged along the transmission direction of the optical path, wherein the first part comprises an incident surface and a first reflecting surface, the second part comprises at least one reflecting surface, the third part comprises an emergent surface, the incident surface and the first reflecting surface are oppositely arranged, and at least one of the incident surface and the first reflecting surface is non-planar.

The laser beam expanding and collimating structure is divided into the first part, the second part and the third part along the light path transmission direction, the first part comprises the incident surface and the first reflecting surface, the second part comprises at least one reflecting surface, the third part comprises the emergent surface, reasonable division of the whole structure is facilitated, meanwhile, the light trend of the inner space of the laser beam expanding and collimating structure is planned, so that light entering the inner space of the laser beam expanding and collimating structure from the incident surface sequentially passes through the first reflecting surface, the second part comprises reflection of the at least one reflecting surface and is emergent from the emergent surface, and beam expanding and collimation of the light beam are realized by reflection. At least one of the incident surface and the first reflecting surface is non-planar, so that the incident surface or the first reflecting surface is favorable for receiving light at different angles, and the application range of the laser beam expanding and collimating structure is increased. According to the utility model, through reasonable planning of the integral structure, collimation and beam expansion of an incident beam are realized, on the premise of ensuring a large beam expansion multiplying power and a large scanning view field, the beam is transmitted in the inner space of the structure, and the optical path is increased, so that the geometric path is reduced, the integral volume is reduced, and the miniaturization is realized.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description serve to explain the utility model. In the drawings:

FIG. 1 shows a schematic structural diagram of a laser beam expanding collimation structure of an alternative embodiment of the present utility model;

FIG. 2 shows another schematic diagram of the laser beam expanding collimating structure of FIG. 1;

FIG. 3 shows a schematic optical path diagram of the laser beam expanding collimating structure of FIG. 1;

FIG. 4 shows a schematic view of a first portion of the laser expanded beam collimation structure of FIG. 1;

FIG. 5 shows a schematic view of a second portion of the laser expanded beam collimation structure of FIG. 1;

FIG. 6 is a schematic diagram of a laser beam expansion and collimation structure according to another alternative embodiment of the utility model at different angles of incidence;

FIG. 7 shows an optical path diagram of a laser beam expanding collimation structure of another alternative embodiment of the utility model;

FIG. 8 shows a schematic view of a third portion of the laser expanded beam collimation structure of FIG. 7;

FIG. 9 illustrates an optical path diagram of a scanning imaging system of an alternative embodiment of the present utility model;

fig. 10 shows a schematic view of the spots of the beam of fig. 9 on the entrance face, the first imaging face and the second imaging face.

Wherein the above figures include the following reference numerals:

10. a first portion; 11. an incidence surface; 12. a first reflecting surface; 20. a second portion; 21. a second reflecting surface; 22. a third reflective surface; 30. a third section; 31. a fourth reflecting surface; 32. an exit surface; 40. MEMS galvanometer; 51. a first imaging plane; 52. and a second imaging plane.

Detailed Description

It should be noted that, without conflict, the embodiments of the present utility model and features of the embodiments may be combined with each other. The utility model will be described in detail below with reference to the drawings in connection with embodiments.

It is noted that all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs unless otherwise indicated.

In the present utility model, unless otherwise indicated, terms of orientation such as "upper, lower, top, bottom" are used generally with respect to the orientation shown in the drawings or with respect to the component itself in the vertical, upright or gravitational direction; also, for ease of understanding and description, "inner and outer" refers to inner and outer relative to the profile of each component itself, but the above-mentioned orientation terms are not intended to limit the present utility model.

The utility model provides a laser beam expanding collimation structure and a scanning imaging system, which aim to solve the problem that the laser beam expanding collimation structure in the prior art is miniaturized, has large beam expanding multiplying power and large scanning visual field and are difficult to simultaneously consider.

As shown in fig. 1 to 10, the laser beam expanding and collimating structure includes a first portion 10, a second portion 20, and a third portion 30 sequentially arranged along a transmission direction of an optical path, the first portion 10 includes an incident surface 11 and a first reflecting surface 12, the second portion 20 includes at least one reflecting surface, the third portion 30 includes an exit surface 32, the incident surface 11 and the first reflecting surface 12 are disposed opposite to each other, and at least one of the incident surface 11 and the first reflecting surface 12 is non-planar.

By dividing the laser beam expansion collimation structure into the first part 10, the second part 20 and the third part 30 along the light path transmission direction, the first part 10 comprises an incident surface 11 and a first reflecting surface 12, the second part 20 comprises at least one reflecting surface, the third part 30 comprises an emergent surface 32, reasonable division of the whole structure is facilitated, meanwhile, the light trend of the inner space of the laser beam expansion collimation structure is planned, so that light entering the inner space of the laser beam expansion collimation structure from the incident surface 11 sequentially passes through the first reflecting surface 12, the second part 20 comprises at least one reflecting surface and is emergent from the emergent surface 32, and beam expansion and collimation of the light beam are realized by reflection. At least one of the incident surface 11 and the first reflecting surface 12 is non-planar, so that the arrangement is beneficial to receiving light with different angles by the incident surface 11 or the first reflecting surface 12, and the application range of the laser beam expanding and collimating structure is increased. According to the utility model, through reasonable planning of the integral structure, collimation and beam expansion of an incident beam are realized, on the premise of ensuring a large beam expansion multiplying power and a large scanning view field, the beam is transmitted in the inner space of the structure, and the optical path is increased, so that the geometric path is reduced, the integral volume is reduced, and the miniaturization is realized.

In summary, the laser beam expansion collimation structure is an immersed reflection system, the volume of the laser beam expansion collimation structure can be further reduced, the scanning view field is increased, the structure can realize laser beam expansion in a 20-degree scanning range within the volume of 0.25cc, and the beam expansion multiplying power of 1-4 times is ensured.

As shown in fig. 1, the third portion 30 further includes a fourth reflecting surface 31, where the fourth reflecting surface 31 is disposed opposite to the emitting surface 32, and the light entering the laser beam expanding and collimating structure from the incident surface 11 sequentially passes through the first reflecting surface 12, at least one reflecting surface of the second portion 20, and the reflection of the fourth reflecting surface 31, and then exits from the emitting surface 32. The distance between the fourth reflecting surface 31 and the emergent surface 32 is gradually reduced along the direction away from the incident surface 11, so that the light in the inner space of the laser beam expansion and collimation structure can be reflected by a plurality of reflecting surfaces to realize the beam expansion of the light beam, and finally the collimation of the light is realized through the fourth reflecting surface 31, thereby being beneficial to the compression of the whole volume and ensuring the better beam expansion and collimation effect; in addition, the distance between the fourth reflecting surface 31 and the emitting surface 32 is gradually reduced along the direction away from the incident surface 11, so that the fourth reflecting surface 31 is beneficial to collimate the received large-angle diffuse light to output parallel light, and the parallel light is emitted from the emitting surface 32, so that stable emitting of a large-range light beam is ensured, meanwhile, loss of light energy can be avoided, and the light transmission efficiency is increased.

Specifically, the second portion 20 includes a second reflecting surface 21 and a third reflecting surface 22, the second reflecting surface 21 and the third reflecting surface 22 are both planes, the second reflecting surface 21 is opposite to and parallel to the third reflecting surface 22, the incident surface 11, the second reflecting surface 21 and the fourth reflecting surface 31 are sequentially connected, and the first reflecting surface 12, the third reflecting surface 22 and the exit surface 32 are sequentially connected. By providing the second portion 20 including two reflecting surfaces, the internal optical path is folded by increasing the number of reflecting surfaces to reduce the overall volume for miniaturization; meanwhile, the small-angle light beam entering the laser beam expansion collimation structure from the incidence surface 11 is transmitted through the first reflection surface 12, the second reflection surface 21 and the third reflection surface 22 in sequence to realize beam expansion, a large-angle divergent light beam is formed, and then the fourth reflection surface 31 collimates the large-angle divergent light beam and is emitted from the emission surface 32, so that the effects of beam collimation and beam expansion are realized.

Referring to fig. 1, the first portion 10, the second portion 20, and the third portion 30 are sequentially connected along a straight line, and the first portion 10, the second portion 20, and the third portion 30 respectively include two optical surfaces, so that the laser beam expanding and collimating structure includes six optical surfaces in total, where the incident surface 11 and the exit surface 32 are transmissive surfaces, the first reflective surface 12 to the fourth reflective surface 31 are all reflective surfaces, and the rest are all absorptive surfaces, and the refractive index of an internal medium of the laser beam expanding and collimating structure is greater than 1, so that a light beam propagates in a medium with a refractive index greater than 1, and an optical path is increased, thereby reducing a geometric path and achieving the purpose of reducing a volume.

Specifically, the distance between the incident surface 11 and the first reflecting surface 12 gradually increases in the direction approaching the exit surface 32. The arrangement is favorable for deflection transmission of the light beam in the laser beam expanding and collimating structure, the second reflecting surface 21 is favorable for stably receiving the light beam reflected by the first reflecting surface 12, the light path transmission path is planned, and the reliability and the stability of the light beam transmission are ensured.

Specifically, the laser beam expansion collimation structure further comprises an antireflection film and an antireflection film, wherein the antireflection film is arranged on at least one of the incident surface 11 and the emergent surface 32, and the antireflection film is arranged on at least one of the first reflecting surface 12, the second reflecting surface 21, the third reflecting surface 22 and the fourth reflecting surface 31. In the embodiment of the present utility model, the incident surface 11 and the exit surface 32 are provided with antireflection films, and the first reflection surface 12, the second reflection surface 21, the third reflection surface 22 and the fourth reflection surface 31 are provided with antireflection films. The antireflection film is added, so that the transmittance of the light beam is increased, and the light beam transmission efficiency is improved; the reflection efficiency of the reflecting surface is increased by adding the reflection increasing film, so that the loss of light energy in the transmission process is avoided.

In an alternative embodiment of the utility model, the entrance face 11 is planar or non-planar, and when the entrance face 11 is planar, the entrance face 11 acts as an entrance window for the entire structure, with no impact on the final imaging quality. When the incident surface 11 is non-planar, the incident surface 11 is convexly disposed in a direction away from the first reflecting surface 12. The non-plane surface includes one of a spherical surface, an aspherical surface, and a free-form surface, and the incident surface 11 can achieve an effect of primary collimation of the non-collimated light beam. After entering the structure from the incident surface 11, the light is reflected by the first reflecting surface 12, and then converged and diverged in the structure, thereby realizing the purpose of beam expansion. When the incident surface 11 is a spherical surface, primary collimation of the laser beam incident with a divergence angle can be achieved. When the incident surface 11 is an aspherical surface or a free-form surface, there may be more variables to eliminate aberrations.

Specifically, the first reflecting surface 12 is used as a main reflecting surface of the laser beam expanding and collimating structure, and the surface shape of the first reflecting surface can be one of a plane, a spherical surface, an aspherical surface and a free curved surface. Preferably, at least the first reflective surface 12 and the fourth reflective surface 31 are non-planar. The fourth reflecting surface 31 is used as a secondary reflecting surface of the laser beam expanding and collimating structure, and the surface shape of the fourth reflecting surface 31 can be one of a plane, a spherical surface, an aspherical surface and a free curved surface. The exit face 32 may be planar or non-planar, and when the exit face 32 is planar, it serves as an exit window of the whole system, and has no influence on the final imaging quality; when the exit surface 32 is non-planar, the exit surface 32 is composed of at least two converging lenses connected, and the exit surface 32 can directly perform converging imaging on the collimated light beam transmitted by the fourth reflecting surface 31. When the exit face 32 is spherical, the exit face 32 achieves convergent imaging of the exit beam. When the exit face 32 is aspheric or freeform, there may be more variables to eliminate aberrations.

Specifically, the refractive index N of the laser beam expansion collimation structure is greater than 1 and less than or equal to 5. The optical path of the entire structure can be expressed as l=n×d (d denotes the geometric path). When the total optical path L is constant, the larger N is, the smaller d is. The refractive index of the dielectric material can realize the reduction of the geometric path of the system, thereby reducing the volume of the system. For the entrance face 11 and the exit face 32, the system achieves convergence or collimation of the light beam according to the law of refraction by refractive index and curvature of the face shape.

In addition, when the reflecting surface is a plane, the refraction of the light path is realized, the influence on the system image quality is avoided, and the processing is simple. When the reflecting surface is spherical, the beam expansion and collimation of the light beam can be realized, and the whole system is simple to process. When the reflecting surface is an aspherical surface or a free-form surface, more variables can be added to eliminate aberration caused by the optical system. For an AR projection optical machine based on MEMS scanning imaging, the reflecting surface is an aspheric surface or a free curved surface, so that light beams in different directions can be perfectly collimated after being expanded, and light spots in different directions can be finally processed to be converged at a focus, so that the light spots are ideally coupled into a waveguide.

It should be noted that, the beam expansion and collimation of the laser beam expansion and collimation structure can be realized through injection molding, coating, machining and other processes. Plastic injection molding is a method of plastic products, in which molten plastic is injected into a plastic product mold by pressure, and various plastic products are obtained by cooling molding. The material used for the optical product is typically PC or PMMA. The optical elements produced mainly by the process are generally in the order of millimeter and above. The size of the laser beam expansion collimation structure is about 10mm, and the laser beam expansion collimation structure is easier to realize by using a plastic injection molding process. The coating process is a common process in the processing process of optical elements, and one or more layers of metal, alloy or metal compound films are coated on the surface of the optical material, so that the optical performance of the optical material can be changed, and certain specific requirements can be met. According to the laser beam expansion collimation structure, a layer of reflection increasing film is plated on the optical surface, so that the reflection effect of the transmission material is achieved. And a layer of black glue is plated on the non-optical surface, so that the phenomenon of light leakage is avoided. Referring to fig. 1, the non-optical surfaces refer to the bottom surface of the first portion 10 and the top surface of the third portion 30. When the machining mode is that the dielectric material is glass, the surface type of the optical element can be machined by processes such as cutting the optics by a machine tool or other tools.

The laser beam expanding and collimating structure of the present utility model is described below with reference to the specific drawings.

As shown in fig. 1 and 5, a laser beam expanding collimation structure of an alternative embodiment of the present utility model is described. As shown in fig. 1 and 2, the laser beam expanding and collimating structure is formed by sequentially connecting a first portion 10, a second portion 20 and a third portion 30, wherein each portion comprises two optical surfaces, the first portion 10 comprises an incident surface 11 and a first reflecting surface 12, the second portion 20 comprises a second reflecting surface 21 and a third reflecting surface 22, and the third portion 30 comprises a fourth reflecting surface 31 and an emergent surface 32. As shown in fig. 3 and fig. 4, the incident surface 11 and the first reflecting surface 12 of the first portion 10 are non-planar, specifically, the incident surface 11 and the first reflecting surface 12 are both curved surfaces, when the incident surface 11 is curved, the incident of the laser beam with a divergence angle can be collimated, and the first reflecting surface 12 is used for reflecting, converging and expanding the collimated beam. As shown in fig. 5, the second reflecting surface 21 and the third reflecting surface 22 of the second portion 20 are both planar, so that the optical path is folded inside, and the system volume is reduced. As shown in fig. 3, the fourth reflecting surface 31 of the third portion 30 is non-planar, specifically, curved, to achieve reflection collimation of the light beam; the exit face 32 is planar, thereby achieving stable exit of parallel light.

As shown in fig. 6, an optical path diagram of a laser beam expanding and collimating structure according to another alternative embodiment of the present utility model at different incident angles is described, and the difference between this embodiment and fig. 1 is that the incident surface 11 is not a curved surface but a plane surface. (a) A schematic diagram of an optical path of the laser beam incident on the incident surface 11 in the +10° direction is shown, and the diameter of the final outgoing beam is 2 times larger than that of the incident beam; (b) A schematic diagram of an optical path for the laser beam to enter the incident surface 11 in the 0-degree direction, wherein the diameter of the final emergent beam is 2 times larger than that of the incident beam; (c) The laser beam is incident on the incident surface 11 in the-10 deg. direction, and the final outgoing beam diameter is 2 times larger than the incident beam diameter.

As shown in fig. 7, a schematic optical path diagram of a laser beam expanding and collimating structure according to another alternative embodiment of the present utility model is described, and the difference between this embodiment and fig. 6 is that the exit surface 32 is non-planar. As shown in fig. 8, which is a schematic diagram of the third portion 30 of the laser beam expanding and collimating structure of the present embodiment, the fourth reflecting surface 31 and the emitting surface 32 of the third portion 30 are curved, where the emitting surface 32 may be regarded as being formed by two surfaces of converging lenses connected, and where the emitting surface 32 may directly perform converging imaging on the collimated light beam transmitted from the fourth reflecting surface 31.

As shown in fig. 9, a scanning imaging system is provided, the scanning imaging system includes a MEMS galvanometer 40 and the laser beam expanding and collimating structure described above, and the MEMS galvanometer 40 is used for emitting light; the laser beam expanding and collimating structure is located on the light emitting side of the MEMS galvanometer 40, and the MEMS galvanometer 40 corresponds to the incident surface 11 of the laser beam expanding and collimating structure. The beams emitted by the MEMS galvanometer 40 are incident on the incident surface 11, collimated and expanded by the laser beam expanding and collimating structure, and finally, the beams in different directions are continuously emitted in different directions after being converged on the first imaging surface 51 and then are incident on the second imaging surface 52.

As shown in fig. 10, (a) is a schematic view of a spot of the beam emitted by the MEMS galvanometer 40 and incident on the incident surface 11; (b) A schematic view of the spots of the light beams in different directions after converging on the first imaging plane 51 is shown; (c) A schematic view of the spot of the light beam in different directions entering the second imaging plane 52 after passing through the first imaging plane 51 is shown. As can be seen from the figure, the laser beam expanding and collimating structure of the present utility model achieves at least twice the beam expanding effect.

In summary, the design of the optical surfaces of the laser beam expansion collimation structure can realize the effects of collimation and beam expansion of the light beam. So as to realize the pupil expansion function of the relay system of the laser beam scanning imaging projection optical machine. The volume of the laser beam expansion collimation structure is greatly reduced, and the laser beam expansion collimation structure is favorable for being assembled in miniaturized head-mounted display equipment such as a projection optical machine and the like, such as an AR projection optical machine. By the integrated design of the plurality of optical surfaces of the laser beam expanding and collimating structure, the utility model can realize the completion of element processing, namely the completion of the whole structure, compared with the traditional reflective collimating and beam expanding system, the utility model reduces the assembling and adjusting process and reduces the tolerance caused by assembly, thereby improving the final imaging quality applied to a laser beam scanning imaging projection optical machine.

It will be apparent that the embodiments described above are merely some, but not all, embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present utility model without making any inventive effort, shall fall within the scope of the present utility model.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present utility model. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present utility model and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that embodiments of the utility model described herein may be implemented in sequences other than those illustrated or otherwise described herein.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (13)

1. The utility model provides a laser beam expansion collimation structure, its characterized in that includes first part (10), second part (20) and third part (30) that set up in order along light path transmission direction, first part (10) are including incident surface (11) and first reflecting surface (12), second part (20) are including at least one reflecting surface, third part (30) are including exit face (32), incident surface (11) with first reflecting surface (12) set up relatively, just incident surface (11) with at least one of first reflecting surface (12) is the nonplanar.

2. The laser beam expanding and collimating structure according to claim 1, characterized in that said third portion (30) further comprises a fourth reflecting surface (31), said fourth reflecting surface (31) being arranged opposite to said exit surface (32), light entering said laser beam expanding and collimating structure from said entrance surface (11) being reflected by said first reflecting surface (12), at least one reflecting surface of said second portion (20), said fourth reflecting surface (31) and then exiting from said exit surface (32) in that order.

3. The laser beam expanding and collimating structure according to claim 2, characterized in that the second portion (20) comprises a second reflecting surface (21) and a third reflecting surface (22), the second reflecting surface (21) being arranged opposite to the third reflecting surface (22), the entrance surface (11), the second reflecting surface (21) and the fourth reflecting surface (31) being connected in sequence, the first reflecting surface (12), the third reflecting surface (22) and the exit surface (32) being connected in sequence.

4. A laser beam expanding and collimating structure according to claim 3, characterized in that the distance between the entrance face (11) and the first reflecting face (12) increases gradually in a direction towards the exit face (32), and the distance between the fourth reflecting face (31) and the exit face (32) decreases gradually in a direction away from the entrance face (11).

5. A laser beam expanding and collimating structure as claimed in claim 3, characterized in that the laser beam expanding and collimating structure further comprises an antireflection film and an antireflection film, the antireflection film is provided on at least one of the incident surface (11) and the exit surface (32), and the antireflection film is provided on at least one of the first reflection surface (12), the second reflection surface (21), the third reflection surface (22) and the fourth reflection surface (31).

6. The laser expanded beam collimation structure as defined in claim 2, wherein at least the first reflecting surface (12) and the fourth reflecting surface (31) are the non-planar surfaces.

7. The laser beam expanding and collimating structure according to claim 1, characterized in that the incident surface (11) is a plane or the non-plane, and that the incident surface (11) is arranged protruding away from the first reflecting surface (12) when the incident surface (11) is non-plane.

8. The laser beam expanding and collimating structure according to claim 1, characterized in that said non-plane comprises one of a spherical surface, an aspherical surface and a free-form surface, said entrance surface (11) and said first reflecting surface (12) being both said non-plane.

9. A laser expanded beam collimation structure as claimed in claim 3, characterized in that the second reflecting surface (21) and the third reflecting surface (22) are both planar, and the second reflecting surface (21) is parallel to the third reflecting surface (22).

10. The laser beam expanding and collimating structure as claimed in claim 3, wherein,

the fourth reflecting surface (31) is the non-plane, and the emergent surface (32) is a plane; or alternatively

The fourth reflecting surface (31) and the exit surface (32) are both said non-planar surfaces.

11. The laser expanded beam collimation structure as defined in claim 2, wherein when the exit face (32) is the non-planar face, the exit face (32) is formed by at least two connectively converging lenses.

12. The laser beam expanding and collimating structure of any one of claims 1 to 11, wherein a refractive index of the laser beam expanding and collimating structure is greater than 1 and less than or equal to 5.

13. A scanning imaging system, comprising:

a MEMS galvanometer (40), the MEMS galvanometer (40) configured to emit light;

the laser beam expanding collimation structure of any one of claims 1 to 12, which is located at the light exit side of the MEMS galvanometer (40), and the MEMS galvanometer (40) corresponds to the incidence plane (11) of the laser beam expanding collimation structure.