CN103944067A - High-power semiconductor laser beam combining system - Google Patents

Abstract

The invention provides a high-power semiconductor laser beam combining system. A laser light source with fine uniformity and single-polarization characteristics can be obtained. The high-power semiconductor laser beam combining system comprises a semiconductor laser stack, a collimation lens assembly and a beam combining device which are sequentially arranged along an optical path, the beam combining device comprises a parallel hexagonal prism and a prism combination, two adjacent side faces of the parallel hexagonal prism face the light exiting direction of the semiconductor laser stack and correspond to the upper half portion and the lower half portion of the semiconductor laser stack respectively in the height direction, so that laser beams emitted by the upper half portion of the semiconductor laser stack sequentially pass the prism combination and the parallel hexagonal prism and then exit along an original optical axis, and laser beams emitted by the lower half portion of the semiconductor laser stack sequentially pass the lower end face and the upper end face of the parallel hexagonal prism, are totally reflected twice and then are parallel to the laser beams emitted by the upper half portion of the semiconductor laser stack to realize plug-in beam combining.

Description

A kind of high-power semiconductor laser closes beam system

Technical field

The invention belongs to laser application, be specifically related to a kind of high-power semiconductor laser and close beam system.

Background technology

Semiconductor laser has advantages of that volume is little, lightweight, reliability is high, long service life, low in energy consumption, the every field that has been widely used at present national economy, but current semiconductor laser apply the restriction that is subject to its beam quality, so improve beam quality, brightness and the power of semiconductor laser, be instantly important research direction.Swash combiner technology development in recent years rapid, it is the process improving beam quality, increase power output, improve power density.Swash combiner technology is used widely in laser processing and high-power optical-fiber coupling product.

Conventional sharp combiner method has polarization coupling at present, and wavelength closes bundle and bundle is closed in space.Common polarization coupling device is comprised of 1/2 slide and polarization splitting prism (PBS), and a part of laser becomes TM (or TM become TE) by polarization state from TE by 1/2 slide, then closes bundle with another part laser.Because the LASER Light Source degree of polarization of semiconductor laser is about 90%, if adopt polarization coupling, optical energy loss is larger, is only applicable to the bundle that closes of quick shaft direction, and output light is mixed polarized light, can not again carry out polarization coupling with other light sources; When using the folded battle array of semiconductor laser as light source, output facula still retains the luminous dead band between bar and bar, and the uniformity is poor.It is that the laser of different wave length closes bundle that wavelength closes bundle, but cannot apply in the occasion that requires laser to have single wavelength, makes it in application, have limitation.

Summary of the invention

In order to overcome the deficiencies in the prior art, the invention provides a kind of high-power semiconductor laser and close beam system, can obtain good uniformity, the LASER Light Source of single polarization characteristic.Scheme is as follows:

This high-power semiconductor laser closes beam system, comprise the semiconductor laser stacks, collimation lens set and the beam merging apparatus that along light path, set gradually, described semiconductor laser stacks forms by several semiconductor laser units are stacking, according to stacks as high, is divided into the first half and the latter half, described beam merging apparatus comprises parallel six prisms and prism combination, parallel six prisms have two adjacent sides towards semiconductor laser stacks light direction, the first half, the latter half of in short transverse, corresponding respectively to described semiconductor laser stacks, wherein the side of parallel six prism the latter halfs is vertical with described light direction, described prism combination comprises several little prisms, little number of prisms is half of laser cell quantity of semiconductor laser stacks, the exiting surface of little prism all fits tightly with the side of parallel six prism the first half, incidence surface is all vertical with described light direction, the position of several prisms in short transverse corresponds respectively to each semiconductor laser unit of the first half of semiconductor laser stacks, make laser beam that semiconductor laser stacks the first half sends successively by prism combine with after parallel six prisms along former optical axis outgoing, the laser beam that semiconductor laser stacks the latter half is sent passes through the lower surface of parallel six prisms successively, carry out after twice total reflection being parallel to each other and forming plug hole and close bundle with semiconductor laser stacks the first half emitting laser light beam in upper surface.

Based on above-mentioned basic scheme, the present invention also does following optimization and limits and improve:

The acute angle angle of parallel six adjacent two sides of prism

If semiconductor laser stacks is comprised of even number semiconductor laser element, the thickness t of parallel six prisms and width L meet:

$t=\frac{(m+1)(w+d)\sin \mathrm{\α}}{2},\left(\frac{2m-1}{4}\right)(w+d)\tan \mathrm{\α}\≤L\≤\frac{m+3}{2}(w+d)\tan \mathrm{\α};$

If semiconductor laser stacks is comprised of odd number semiconductor laser element, the thickness t of parallel six prisms and width meet:

$t=\frac{m(w+d)\sin \mathrm{\α}}{2};\frac{m}{2}(w+d)\tan \mathrm{\α}\≤L\≤\frac{2m+5}{4}(w+d)\tan \mathrm{\α};$

Wherein, m is semiconductor laser element quantity; W is the spacing between adjacent two semiconductor laser elements; T is the thickness of parallel six prisms; L is the width of parallel six prisms, and n is the refractive index of parallel six prism materials.

The preferred prism of little prism in above-mentioned prism combination, each little prism is equidistantly placed, and meets following relation:

a＝b，w>d，d≤x≤w；

Wherein d is the beam diameter after single semiconductor laser unit collimation, and a is prism exiting surface width, the spacing that b is prism, and the plane of incidence height that x is prism, w is the spacing between adjacent two semiconductor laser elements.

Above-mentioned semiconductor laser unit is the semiconductor laser chip being welded on heat sink, and described semiconductor laser chip is a single tube chip, mini bar or bar bar, or be a plurality of single tube chips, mini bar or cling to bar.

Above-mentioned collimation lens set comprises fast axis collimation lens and slow axis collimating array, and wherein, fast axis collimation lens is collimation D type non-spherical lens, and slow axis collimating array is single array cylindrical lens.

The material of above-mentioned parallel six prisms is glass, and the plane of incidence and exit facet all plate anti-reflection film.

The present invention has the following advantages:

1) this semiconductor laser closes the laser beam that beam system sends and has single polarization characteristic, so system optical energy loss rate is low;

2) this semiconductor laser closes beam system employing plug hole and closes Shu Fangfa, the uniformity of outgoing hot spot is very high, and reduces the object of light long-pending ginseng BPP (light-emitting area is multiplied by the angle of divergence), can improve beam quality, improve its output power density, make it be more conducive to application;

3) this semiconductor laser closes beam system and can be applicable to fast and slow axis simultaneously;

4) processing is simple, and fully reflecting surface does not need plated film can realize total reflection, and cost of manufacture is low.

Accompanying drawing explanation

Fig. 1 is that a kind of high-power semiconductor laser closes beam system schematic diagram;

Fig. 2-1 is for closing installation site and the size schematic diagram of prism combination in beam system;

Fig. 2-2 are semiconductor laser stacks sizing specification figure;

Fig. 3 is the sizing specification figure that closes parallel six prisms in beam system.

Drawing reference numeral explanation: 1 is semiconductor laser stacks, and 2 is fast axis collimation lens, and 3 is slow axis collimating array, and 4 is parallel six prisms, 5 is prism combination, 6 is prism combination installation region; 7 is total reflection district, and 8 is collimation lens set, and 9 is beam merging apparatus.

Embodiment

Below in conjunction with example and accompanying drawing, the solution of the present invention is described further, Fig. 1 is that a kind of high-power semiconductor laser closes beam system schematic diagram, a kind of high-power semiconductor laser closes beam system and comprises semiconductor laser stacks 1, collimation lens set 8 and the beam merging apparatus 9 setting gradually along light path, wherein the little prism in the combination of the prism in beam merging apparatus 95 is selected with prism, and the angle of the acute angle of adjacent two sides of parallel six prisms 4 is 45 °.Semiconductor laser 1 comprise 4 semiconductor laser elements and be divided into upper and lower two parts using top 2 semiconductor laser elements as the upper part of semiconductor laser stacks, 2 semiconductor laser elements of bottom are as the lower part of semiconductor laser stacks, little prism in prism combination is 2 prisms, the plane of incidence of 2 prisms in the combination of laser beam vertical incidence prism is divided on semiconductor laser stacks top, it is the plane of incidence that laser that 2 semiconductor laser elements on semiconductor laser stacks top send is incident to respectively 2 prisms, because laser beam incident direction is vertical with the prism plane of incidence, so can not reflect in prism inside, laser beam is incident to after the prism plane of incidence level from the exit facet outgoing of parallel six prisms, be that exit direction is consistent with incident direction, semiconductor laser stacks bottom divides the laser beam plug hole of outgoing to close Shu Shuiping outgoing with top after dividing parallel six prisms of laser beam vertical incidence after two relative faces of parallel six prisms carry out twice total reflection.The energy density of closing light beams is that 2 times of incident optical energy metric density and the diameter that closes light beams are half of the laser diameter that sends of semiconductor laser stacks, reduced the object of light long-pending ginseng BPP (light-emitting area is multiplied by the angle of divergence), can improve beam quality, improve its output power density, make it be more conducive to application.

As shown in Figure 3, semiconductor laser stacks is comprised of 4 semiconductor laser elements, and the thickness t of parallel six prisms and width L meet:

$t=\frac{5\sqrt{2}}{4}(w+d),\frac{3}{4}(w+d)\≤L\≤\frac{7}{2}(w+d);$

W is the spacing between adjacent two semiconductor laser elements; T is the thickness of parallel six prisms; L is the width of parallel six prisms.

Little prism in described prism combination adopts prism, and each little prism is equidistantly placed, and meets following relation:

a＝b，w>d，d≤x≤w；

Wherein d is the beam diameter after single semiconductor laser unit collimation, and a is prism exiting surface width, the spacing that b is prism, and the plane of incidence height that x is prism, w is the spacing between adjacent two semiconductor laser elements.

The acute angle angle of adjacent two sides of above-mentioned parallel six prisms meets

$\mathrm{\α}\≥\arcsin \left(\frac{1}{n}\right)$

Described semiconductor laser unit is the semiconductor laser chip being welded on heat sink, and described semiconductor laser chip is a single tube chip, mini bar or bar bar, or be a plurality of single tube chips, mini bar or cling to bar.

Described collimation lens set comprises fast axis collimation lens and slow axis collimating array, and wherein, fast axis collimation lens is collimation D type non-spherical lens, and slow axis collimating array is single array cylindrical lens.

The material of described parallel six prisms is glass, and the plane of incidence and exit facet all plate anti-reflection film.

Wherein the little prism of prism combination can be prism, but is not limited to prism, can also be polygon prism.

Claims (6)

1. a high-power semiconductor laser closes beam system, it is characterized in that: comprise the semiconductor laser stacks, collimation lens set and the beam merging apparatus that along light path, set gradually, described semiconductor laser stacks forms by several semiconductor laser units are stacking, according to stacks as high, is divided into the first half and the latter half, described beam merging apparatus comprises parallel six prisms and prism combination, parallel six prisms have two adjacent sides towards semiconductor laser stacks light direction, the first half, the latter half of in short transverse, corresponding respectively to described semiconductor laser stacks, wherein the side of parallel six prism the latter halfs is vertical with described light direction, described prism combination comprises several little prisms, little number of prisms is half of laser cell quantity of semiconductor laser stacks, the exiting surface of little prism all fits tightly with the side of parallel six prism the first half, incidence surface is all vertical with described light direction, the position of several prisms in short transverse corresponds respectively to each semiconductor laser unit of the first half of semiconductor laser stacks, make laser beam that semiconductor laser stacks the first half sends successively by prism combine with after parallel six prisms along former optical axis outgoing, the laser beam that semiconductor laser stacks the latter half is sent passes through the lower surface of parallel six prisms successively, carry out after twice total reflection being parallel to each other and forming plug hole and close bundle with semiconductor laser stacks the first half emitting laser light beam in upper surface.

2. high-power semiconductor laser according to claim 1 closes beam system, it is characterized in that:

The acute angle angle of parallel six adjacent two sides of prism

Semiconductor laser stacks is comprised of even number semiconductor laser element, and the thickness t of parallel six prisms and width L meet:

$t=\frac{(m+1)(w+d)\sin \mathrm{\α}}{2},\left(\frac{2m-1}{4}\right)(w+d)\tan \mathrm{\α}\≤L\≤\frac{m+3}{2}(w+d)\tan \mathrm{\α};$

Or

Semiconductor laser stacks is comprised of odd number semiconductor laser element, and the thickness t of parallel six prisms and width meet:

$t=\frac{m(w+d)\sin \mathrm{\α}}{2};\frac{m}{2}(w+d)\tan \mathrm{\α}\≤L\≤\frac{2m+5}{4}(w+d)\tan \mathrm{\α};$

M is semiconductor laser element quantity; W is the spacing between adjacent two semiconductor laser elements; T is the thickness of parallel six prisms; L is the width of parallel six prisms, and n is the refractive index of parallel six prism materials.

3. high-power semiconductor laser according to claim 1 closes beam system, it is characterized in that: the little prism in described prism combination adopts prism, and each little prism is equidistantly placed, and meets following relation:

a＝b，w>d，d≤x≤w；

Wherein d is the beam diameter after single semiconductor laser unit collimation, and a is prism exiting surface width, the spacing that b is prism, and the plane of incidence height that x is prism, w is the spacing between adjacent two semiconductor laser elements.

4. high-power semiconductor laser according to claim 1 closes beam system, it is characterized in that: described semiconductor laser unit is the semiconductor laser chip being welded on heat sink, described semiconductor laser chip is a single tube chip, mini bar or bar bar, or is a plurality of single tube chips, mini bar or bar bar.

5. high-power semiconductor laser according to claim 1 closes beam system, it is characterized in that: described collimation lens set comprises fast axis collimation lens and slow axis collimating array, wherein, fast axis collimation lens is collimation D type non-spherical lens, and slow axis collimating array is single array cylindrical lens.

6. high-power semiconductor laser according to claim 1 closes beam system, it is characterized in that: the material of described parallel six prisms is glass, and the plane of incidence and exit facet all plate anti-reflection film.