CN112965259A

CN112965259A - Multi-aperture light beam dodging module and optical device

Info

Publication number: CN112965259A
Application number: CN202110284720.5A
Authority: CN
Inventors: 朱兵兵; 董英琴; 赵金平
Original assignee: Sansui Optical Technology Suzhou Co Ltd
Current assignee: Sansui Optical Technology Suzhou Co Ltd
Priority date: 2021-03-17
Filing date: 2021-03-17
Publication date: 2021-06-15

Abstract

The invention relates to a multi-aperture light beam dodging module which comprises a Glens array and a convex lens; the Glens array is located within 1.2 times of the focal length of the convex lens, the Glens optical axis is parallel to the lens optical axis, the Glens array can divide an incident laser beam into a plurality of sub-beams to be emitted at a certain diffusion angle, the sub-beams pass through the convex lens and are superposed and homogenized on the back focal plane of the convex lens. The invention also provides an optical device provided with the multi-aperture beam dodging module. The invention provides a multi-aperture beam dodging module and an optical device, which can divide a laser beam incident in parallel into a plurality of sub-beams to be emitted at a certain diffusion angle, and the sub-beams can be superposed and homogenized on the back focal plane of a convex lens after passing through the convex lens.

Description

Multi-aperture light beam dodging module and optical device

Technical Field

The invention relates to the technical field of optical machines, in particular to a multi-aperture light beam dodging module and an optical device.

Background

In order to improve the quality of laser beams and meet different use scenes, the shaping technology aiming at the laser beams has become a hot spot of optical research at home and abroad. With the continuous development of laser shaping technology, the theoretical design of laser beam homogenization is mainly divided into two categories, one is a beam homogenization method based on the geometrical optics principle, and the other is a beam homogenization method based on the diffraction optics principle. The widely used beam energy homogenizing device comprises a binary optical element, a birefringent lens group, an aspheric lens group, a liquid crystal spatial light modulator, a beam integrator and the like, and has advantages and disadvantages for the mainstream laser beam homogenizing methods, for example, the binary optical element can achieve shaping and light homogenizing effects, but is limited by the difficulty of a photoetching process and high processing cost; the aspherical lens group method has high shaping efficiency but high light intensity sensitivity, and the laser shaping effect is poor; the design theory of the beam integrator is relatively mature, and the shaping and light-homogenizing effects are good. The beam integrators commonly used at present include two types, one is a single aperture beam integrator, such as a dodging rod; the other type is a multi-aperture beam integrator, a general spherical or aspheric micro-lens array such as a fly-eye lens and the like has strong laser damage resistance and is insensitive to incident light intensity, the device is limited by the processing technology of the prior quartz non-lens array, the cost is still high, in addition, due to the fact that the surface of the device is provided with an uneven microstructure, other magazines are easily accumulated on the surface to influence the beam quality, and the device has higher use environment requirements.

Patent CN1243989C discloses a reflective fly-eye beam homogenizer, which is composed of two identical reflective microlens arrays, the microlens arrays are concave mirror arrays plated with total reflection films, and the major disadvantages are large loss, high requirement for position accuracy of two fly-eye lens arrays during application, and difficult cleaning of dirty surfaces. Patent CN209167711U discloses a microarray comprising a plurality of microarrays with irregular quadrilateral apertures, each microarray with irregular quadrilateral aperture is composed of a continuous surface type curved surface, the light-equalizing principle is the same as that of a general multi-aperture integrator, and the purpose is to reduce the interference problem in the light equalization of the conventional periodic microlens array by irregular arrangement, but the problem of surface contamination and difficulty in cleaning is also existed, and the processing difficulty is large.

In order to solve the above problems, the present applicant proposes a multi-aperture beam dodging module and an optical device.

Disclosure of Invention

Aiming at the defects of complexity, poor dodging effect, high cost, harsh use environment and the like of the conventional laser dodging system, the invention provides the multi-aperture beam dodging module which can divide a laser beam which is incident in parallel into a plurality of sub-beams to be emitted at a certain diffusion angle, and the sub-beams can be superposed and homogenized on the back focal plane of a convex lens after passing through the convex lens.

To achieve the above-mentioned object, the multi-aperture beam dodging module of the present invention comprises a Glens (Graded index lens, also called self-focusing lens) array and a convex lens; the Glens array is located within 1.2 times of the focal length of the convex lens, divides an incident laser beam into a plurality of sub-beams to be emitted at a certain diffusion angle, and the sub-beams pass through the convex lens and are superposed and homogenized on the back focal plane of the convex lens.

Preferably, the Glens array comprises a plurality of V grooves arranged in parallel and a plurality of Glens lenses, the Glens lenses are arranged in the V grooves arranged in parallel in turn to form a periodic arrangement, and a light-tight material is filled between the adjacent Glens lenses.

Preferably, the preparation method of the Glens array comprises the following steps:

s1, preparing a plurality of Glens lenses with the length of L and the diameter of D;

s2, preparing V grooves arranged in parallel;

s3, arranging the Glens lenses on the V groove in parallel and tightly, and bonding the Glens lenses through opaque glue to form a Glen S panel with a single-layer structure;

s4, stacking a plurality of single-layer-structure Glens panels to form a multilayered-structure Glens panel, and bundling and sealing the side periphery of the multilayered-structure Glens panel by using a plastic film or an adhesive tape;

s5, soaking the stacked Glens array structure in opaque glue, taking out the Glens array after the glue permeates and fills the gaps in the Glens, sealing the end face of the Glens array with an adhesive tape, and drying the Glens array in a drying cabinet to quickly cure the glue;

and S6, cutting the panel into required lengths, polishing two cut end faces and plating an antireflection film to form the Glens array.

Preferably, the opaque material is opaque glass or resin.

Preferably, the several Glens lenses are of equal length.

Preferably, the length of the Glens lens is 0.23 to 0.25Pich (pitch) or 0.7 to 0.75 Pich. The track of the light ray in Glens presents a sine curve or a cosine curve, and one Pich is the length of one period of the light ray track. For parallel incident light, the propagation path in Glens is cosine curve, so that there is better focusing effect at 0.23-0.25 Pich (pitch) and 0.7-0.75 Pich.

Preferably, the Glens lens is a columnar structure, and the section of the Glens lens can be circular or rectangular.

Another object of the present invention is to provide an optical device comprising the above multi-aperture beam dodging module.

Compared with the prior art, the multi-aperture light beam dodging module and the optical device further have the following advantages:

(1) the whole dodging module has compact structure, small device volume and diversified structure, and is suitable for various optical systems;

(2) the device is of a flat plate structure, has no microstructure on the surface, is not easy to accumulate dust, and has good light emitting quality;

(3) the method is suitable for batch production, and greatly improves the production efficiency;

(4) the mode is suitable for generating uniform laser beams, and the device has a flat plate structure, so that the device can be in no air contact with optical elements with other flat plate structures, and the volume of an optical system is greatly reduced.

Drawings

FIG. 1 is a schematic view of a Glens panel of this embodiment having a rectangular cross-section;

FIG. 2 is a schematic view of a Glens panel of this embodiment having a circular cross-section;

FIG. 3 is a schematic structural diagram of a single Glens lens in this example;

fig. 4 is a schematic optical path diagram of a multi-aperture beam dodging module according to this embodiment.

Detailed Description

The invention is further described below with reference to the following figures and specific examples.

A multi-aperture beam dodging module comprises a Glens array and a convex lens; the Glens array is located within 1.2 times of the focal length of the convex lens, when the Glens array exceeds 1.2 times of the focal length, the uniformity is obviously reduced (< 80%), the central brightness of a light spot is lower than the edge, the Glens array divides an incident laser beam into a plurality of sub-beams to be emitted at a certain diffusion angle, the sub-beams pass through the convex lens, and the sub-beams are superposed and homogenized on the back focal plane of the convex lens.

The inventor herein discloses a specific Glens array structure, the Glens array comprises a plurality of V-grooves arranged in parallel and a plurality of Glens lenses, the Glens lenses are arranged in the V-grooves arranged in parallel in turn to form periodic arrangement, and an opaque material is filled between the adjacent Glens lenses, wherein the opaque material can be Bayer BEEP 6113 two-component epoxy resin (the opaque material can also be low-transmittance glass prepared by co-firing coloring powder such as iron oxide, copper oxide, cobalt oxide and the like and low-melting-point (about 400 ℃) phosphate glass). The purpose of filling the opaque material is to prevent light that does not enter Glen s from directly passing out of the gap to affect the dodging effect.

The track of the light ray in Glens presents a sine curve or a cosine curve, and one Pich is the length of one period of the light ray track. For parallel incident light, the propagation path in Glens is cosine curve, so that there is better focusing effect at 0.23-0.25 Pich (pitch) and 0.7-0.75 Pich. In this example, the Glens lens length is 0.23 Pich.

Further, the lengths of the plurality of Glens lenses are equal, and the arrangement is such that the focal points are in the same plane for each lens unit.

Further, as shown in fig. 1 to 3, the Glens lens is of a cylindrical structure, the cross section of the Glens lens can be in various geometric shapes such as a circle and a rectangle, and the selection significance of different geometric shapes is that the design requirements of different optical systems are met, so that the Glens lens is convenient to install in an optical machine product.

The working principle is as follows: as shown in fig. 4, a beam of parallel light is perpendicularly incident on the entrance surface of the Glens array, each sub-beam entering the Glens unit is focused by the Glens at the rear end of the Glens light exit surface to form a plurality of sub-light sources, because the length of the Glens lenses is the same, the focusing point is on the plane perpendicular to the optical axis, the light rays of the sub-light sources can be re-imaged by the integrator lens behind the Glens and are overlapped at the focal plane, so that each point on the focal plane is equivalent to the superposition of the light intensities of the sub-light sources reaching the point, and the light is uniformly emitted.

The preparation method of the Glens array in the multi-aperture light beam dodging module mainly comprises the following steps,

s2, preparing V grooves arranged in parallel;

s3, arranging the Glens lenses on the V groove in a parallel and tight mode, and bonding the Glens lenses through opaque glue (preferably black double-component epoxy resin) to form a Glens panel with a single-layer structure;

According to the Glens array prepared by the method, when a semiconductor laser collimation light source with the wavelength of 638nm is used for incidence, a Gaussian beam with the diameter of 3mm can be homogenized and shaped into a uniform flat-top light spot with the uniformity of over 85% (Imin/Imax) and the diameter of 5mm, and the requirement of the display industry for the uniform light spot is met (more than 80%). And through theoretical plan, the size of the Glens unit is further reduced, and when the ratio of the Glens diameter to the incident light spot diameter is smaller than 1/100, the light beam is divided into a plurality of sub-beams as much as possible, so that the final uniformity can reach more than 95%.

In the description of the present specification, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience of describing the technical solutions of the present patent and for simplification of the description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be interpreted as limiting the present patent application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this patent application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In this specification, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integral to one another; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present specification can be understood by those of ordinary skill in the art as appropriate.

In this specification, unless explicitly stated or limited otherwise, a first feature may be "on" or "under" a second feature such that the first and second features are in direct contact, or the first and second features are in indirect contact via an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. A multi-aperture beam dodging module is characterized by comprising a Glens array and a convex lens; the Glens array is located within 1.2 times the focal length of the convex lens.

2. The multi-aperture beam dodging module of claim 1, wherein said Glens array comprises a plurality of parallel V-grooves and a plurality of Glens lenses, said Glens lenses being disposed one after another in said parallel V-grooves to form a periodic arrangement, and said adjacent Glens lenses being filled with an opaque material.

3. The multi-aperture beam dodging module of claim 2, wherein the Glens array is prepared as follows:

s2, preparing V grooves arranged in parallel;

s3, arranging the Glens lenses on the V groove in a parallel and tight mode, and bonding the Glens lenses through opaque glue to form a Glens panel with a single-layer structure;

4. The multi-aperture beam dodging module of claim 3, wherein said opaque material is an opaque glass or resin.

5. The multi-aperture beam dodging module of any one of claims 2 to 4, wherein said plurality of Glens lenses are equal in length.

6. The multi-aperture beam dodging module of any one of claims 2 to 4, wherein said plurality of Glens lenses have a length of 0.23 to 0.25Pich or 0.7 to 0.75 Pich.

7. The multi-aperture beam dodging module of any one of claims 2 to 4, wherein said Glens lens has a cylindrical structure with a circular or rectangular cross-section.

8. An optical device comprising the multi-aperture beam dodging module of any one of claims 1 to 7.