CN112864792A

CN112864792A - Semiconductor laser module and optical system

Info

Publication number: CN112864792A
Application number: CN202110028967.0A
Authority: CN
Inventors: 蔡磊; 刘兴胜
Original assignee: Focuslight Technologies Inc
Current assignee: Focuslight Technologies Inc
Priority date: 2021-01-08
Filing date: 2021-01-08
Publication date: 2021-05-28

Abstract

The utility model provides a semiconductor laser module and optical system, relate to semiconductor laser technical field, including the semiconductor laser array, and continuous reflector and the space beam combiner that set gradually along the laser beam emergent direction of semiconductor laser array, the laser beam of outgoing includes parallel first light beam and second light beam, first light beam sees through the space beam combiner outgoing after turning back in continuous reflector, the second light beam is the contained angle incident space beam combiner through the income light side of space beam combiner with first light beam, and through the reflection of space beam combiner and the emergent of first light beam combination, the optical path of first light beam in continuous reflector equals with the optical path of second light beam through the income light side incident space beam combiner of space beam combiner. The first light beam is folded back by the continuous reflector, the optical path is prolonged, and the first light beam is emitted out through the spatial beam combiner; the second light beam is incident to the space beam combiner and is inserted into the first light beam to form continuous and dense light beams. The optical path difference is zero, and the uniformity and the continuity of light spots are good.

Description

Semiconductor laser module and optical system

Technical Field

The application relates to the technical field of semiconductor lasers, in particular to a semiconductor laser module and an optical system.

Background

In the process of transmitting light beams emitted by the light source, the light beams are influenced by optical elements, external factors and the like, the light beams are discontinuous, and dead zones are formed by the light rays, so that the continuity and the uniformity of formed light spots are poor. In order to solve the above problems, it is generally adopted that a part of the light beam is directly emitted, another part of the light beam is folded back through the light path and then spliced with the directly emitted light beam, and the light beam folded back through the light path is spliced in a form of splicing to fill a dead zone formed by the directly emitted light beam, so that continuous and dense light beams can be formed after being spliced. This method of splitting the same light source into one set of folded back and another set of stitched bundles to form continuous and dense light is called self-space beam combining method.

For self-space beam combination, although the situation of discontinuous light beams is improved, the optical path difference is formed between the directly emergent light beams and the light beams after the light path is folded back, and the light spots formed by beam combination are not uniform due to the optical path difference.

In order to eliminate the optical path difference of the self-space beam combining light, in the prior art, an optical waveguide is arranged on the light emitting side of the self-space beam combining light, and the light is recombined in the optical waveguide and then emitted again, so that the optical path difference of the self-space beam combining light is eliminated.

Disclosure of Invention

An object of the embodiments of the present application is to provide a semiconductor laser module and an optical system, which can eliminate the optical path difference of self-space beam combining light, output high-quality line light spots, and have compact overall design and small size.

An aspect of the embodiment of the application provides a semiconductor laser module, including the semiconductor laser array, and follow continuous reflector and space beam combiner that the laser beam outgoing direction of semiconductor laser array set gradually, the laser beam of outgoing includes parallel first light beam and second light beam, first light beam is in see through after turning back in the continuous reflector the space beam combiner outgoing, the second light beam warp the income light side of space beam combiner with first light beam is the contained angle and incides the space beam combiner, and the warp the space beam combiner reflection with first light beam combines the beam outgoing, first light beam is in optical path in the continuous reflector with the second light beam warp the income light side of space beam combiner is incited the optical path of space beam combiner equals.

Optionally, the continuous reflector includes at least three reflecting surfaces, and the first light beam is reflected by the at least three reflecting surfaces in sequence and then enters the spatial beam combiner.

Optionally, the continuous reflector includes a special-shaped prism having a first total reflection surface, a second total reflection surface, and a third total reflection surface that totally reflect the first light beam in sequence; or the continuous reflector comprises three first reflecting mirrors which are fixedly arranged respectively and reflect the first light beams in sequence; wherein the direction in which the first light beam enters the continuous reflector is the same as the direction in which the first light beam exits the continuous reflector.

Optionally, the continuous reflector includes a special-shaped prism having a first total reflection surface, a second total reflection surface, a third total reflection surface, and a fourth total reflection surface that totally reflect the first light beam in sequence; or the continuous reflector comprises four first reflecting mirrors which are fixedly arranged respectively and sequentially reflect the first light beams; wherein the direction in which the first light beam enters the continuous reflector is the same as the direction in which the first light beam exits the continuous reflector.

Optionally, the second light beam is reflected at least twice in the spatial beam combiner and then is spliced with the first light beam to be emitted.

Optionally, the polarization beam combiner further includes a polarization beam group disposed on the light exit side of the spatial beam combiner, and the polarization beam group adjusts the polarization state of the light beam exiting from the combined beam.

Optionally, the polarization light group includes a first polarizer and an 1/4 wave plate sequentially arranged along the optical path direction, and linearly polarized light passing through the first polarizer is converted into circularly polarized light by the 1/4 wave plate.

Optionally, the polarized light group further includes a second polarizing plate parallel to the first polarizing plate, a light-absorbing plate is disposed on a light-emitting side of the second polarizing plate, the first polarizing plate is disposed on the main light path at an included angle, and the laser beam reflected by the processing surface is reflected by the first polarizing plate and the second polarizing plate in sequence and then emitted to the light-absorbing plate.

Optionally, the polarization beam splitter further comprises a slow-axis dodging mirror group arranged on the light-emitting side of the polarization light group, and the slow-axis dodging mirror group is used for collimating and homogenizing the slow axis direction of the light beam.

Optionally, the slow-axis dodging mirror group comprises at least one positive lens and at least one micro-array lens.

Optionally, the slow-axis dodging mirror group comprises a first positive lens, a micro-array lens and a second positive lens which are sequentially arranged; or the slow-axis dodging mirror group comprises a micro-array lens, a first positive lens and a second positive lens which are arranged in sequence.

Optionally, the polarization beam splitter further comprises a fast axis adjusting mirror group arranged on the light exit side of the polarization beam group, and the fast axis adjusting mirror group is used for expanding the beam in the fast axis direction of the light beam and then focusing the beam.

Optionally, a slow-axis dodging mirror group and a fast-axis adjusting mirror group are arranged on the light emitting side of the polarized light group, the slow-axis dodging mirror group is located in front of the fast-axis adjusting mirror group, and light beams enter the fast-axis adjusting mirror group after passing through the slow-axis dodging mirror group.

Optionally, the fast axis adjusting mirror group comprises a beam expander, a collimator and a beam reducer, which are sequentially arranged.

Optionally, the beam expander is a negative lens, the collimator is a third positive lens, and the beam reducer includes at least one fourth positive lens.

Optionally, the beam reducer further includes a meniscus lens disposed on the light exit side of the fourth positive lens.

Optionally, a third reflector is further disposed on the main light path, and the third reflector and the main light path are arranged at an included angle to change the direction of the light beam passing through the third reflector.

In another aspect of the embodiments of the present application, an optical system is provided, which includes the semiconductor laser module described above.

According to the semiconductor laser module and the optical system provided by the embodiment of the application, a semiconductor laser array is adopted to emit laser beams, the laser beams comprise a first light beam and a second light beam which are parallel to each other, the first light beam enters a continuous reflector, after the first light beam is turned back by the continuous reflector, the optical path of the first light beam is prolonged, and then the first light beam is emitted through a space beam combiner; the second light beam directly enters the space beam combiner, after passing through the light inlet side of the space beam combiner, the light path of the second light beam is changed to form an included angle with the first light beam, and the second light beam is reflected by the space beam combiner, after reflection, the second light beam is inserted into the dead zone of the first light beam to form a light beam with the first light beam, and the formed light beam is continuous and dense. And the optical path of the first light beam in the continuous reflector is equal to the optical path of the second light beam entering the spatial beam combiner through the light entrance side of the spatial beam combiner, the optical path difference between the first light beam and the second light beam is zero, the uniformity and the continuity of light spots formed by the light beams after the optical path difference is eliminated are good, and high-quality linear light spots can be output. The embodiment of the application changes the light path of the second light beam through the turn-back of the continuous reflector to the first light beam and the space beam combiner, and the first light beam and the second light beam are combined and emitted.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a semiconductor laser module provided in this embodiment;

fig. 2 is a schematic diagram of a fast axis optical path of the semiconductor laser module provided in this embodiment;

fig. 3 is a diagram of energy density of a light spot formed by a fast axis optical path of the semiconductor laser module provided in this embodiment;

fig. 4 is a schematic diagram of a slow axis optical path of the semiconductor laser module provided in this embodiment;

fig. 5 is a diagram of energy density of a light spot formed by a slow-axis optical path of the semiconductor laser module provided in this embodiment;

fig. 6 is a schematic diagram of an optical path of a laser beam passing through a continuum reflector and a spatial beam combiner in the semiconductor laser module provided in this embodiment;

FIG. 7 is a schematic diagram of the optical path of the laser beam passing through the continuum reflector in the semiconductor laser module provided in this embodiment;

FIG. 8 is a second schematic diagram of the optical path of the laser beam passing through the continuous reflector in the semiconductor laser module provided in this embodiment;

fig. 9 is a schematic diagram of a slow-axis optical path of a laser beam passing through a continuum reflector in the semiconductor laser module provided in this embodiment;

fig. 10 is a third schematic optical path diagram of a laser beam passing through a continuous reflector in the semiconductor laser module provided in this embodiment;

fig. 11 is a schematic diagram of an optical path of a laser beam passing through a prism in the semiconductor laser module provided in this embodiment;

fig. 12 is a schematic diagram of an optical path of a laser beam passing through a polarization light group in the semiconductor laser module provided in this embodiment;

FIG. 13 is a schematic diagram of the optical paths of the laser beams passing through the slow-axis dodging mirror set in the semiconductor laser module according to this embodiment;

FIG. 14 is a second schematic optical path diagram of a laser beam passing through a slow-axis dodging mirror set in the semiconductor laser module according to this embodiment;

fig. 15 is a schematic diagram of an optical path of a laser beam passing through a fast axis adjusting mirror set in the semiconductor laser module provided in this embodiment;

fig. 16 is a schematic structural diagram of a semiconductor laser module provided with a third reflector in this embodiment;

fig. 17 is a schematic diagram of a chip bar and a heat sink structure provided in this embodiment;

fig. 18 is one of schematic diagrams of a stacked structure formed by the chip bar and the heat sink provided by the present embodiment;

fig. 19 is a second schematic diagram of a stacked structure formed by the chip bar and the heat sink provided in this embodiment.

Icon: 10-an array of semiconductor lasers; 11-chipbars; 12-a heat sink; 13-collimating micro-lenses; 101-a first semiconductor laser array; 102-a second semiconductor laser array; 100-a continuous reflector; 110-a first mirror; 120-a profiled prism; 121-a first total reflection surface; 122-a second total reflection surface; 123-a third total reflection surface; 124-fourth total reflection surface; 200-a spatial combiner; 201-a second mirror; 202-a striped mirror; 203-six prisms; 204-triple prism; 210-incident side; 300-polarized light group; 301-a first polarizer; 302-1/4 wave plates; 303 — a second polarizer; 401-a micro-array lens; 402-a first positive lens; 403-a second positive lens; 501-negative lens; 502-third positive lens; 503-a fourth positive lens; 504-meniscus lens; 601-window mirror; 701-a third mirror; 702-a fourth mirror.

Detailed Description

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

In the description of the present application, it should be noted that the terms "inside", "outside", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that the products of the application usually place when using, and are only used for convenience in describing the present application and simplifying the description, but do not indicate or imply that the devices or elements that are referred to must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

It should also be noted that, unless expressly stated or limited otherwise, the terms "disposed" and "connected" are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

Referring to fig. 1, an embodiment of the present application provides a semiconductor laser module, including a semiconductor laser array 10, and a continuous reflector 100 and a spatial beam combiner 200 sequentially disposed along an exit direction of laser beams of the semiconductor laser array 10, where the emitted laser beams include a first light beam and a second light beam that are parallel, the first light beam is reflected back in the continuous reflector 100 and then exits through the spatial beam combiner 200, the second light beam enters the spatial beam combiner 200 through a light incident side 210 of the spatial beam combiner 200 at an included angle with the first light beam, and is reflected by the spatial beam combiner 200 to exit as a combined first light beam, and a light path of the first light beam in the continuous reflector 100 is equal to a light path of the second light beam entering the spatial beam combiner 200 through the light incident side 210 of the spatial beam combiner 200.

The light source is a semiconductor laser array 10, and the semiconductor laser array 10 emits a laser beam, which includes a first beam and a second beam, and the first beam and the second beam are parallel. As shown in fig. 2, the semiconductor laser array 10 includes a first semiconductor laser array 101 and a second semiconductor laser array 102; the first light beam is emitted by the first semiconductor laser array 101 and the second light beam is emitted by the second semiconductor laser array 102. When the laser beam is emitted, the first light beam is formed above the light emitting side of the semiconductor laser array 10, the second light beam is formed below the light emitting side of the semiconductor laser array 10, and the first light beam and the second light beam are emitted in parallel to the rear end optical element.

As shown in fig. 4, the first light beam enters the continuous reflector 100, and after being folded back for a plurality of times in the continuous reflector 100, the optical path of the first light beam is extended, and the first light beam with the extended optical path enters the spatial beam combiner 200 again and then exits from the spatial beam combiner 200.

The second light beam enters the spatial beam combiner 200 from the light entrance side 210 of the spatial beam combiner 200, the light entrance side 210 faces the direction of the laser beam emitted by the semiconductor laser array 10, after entering from the light entrance side 210 of the spatial beam combiner 200, the light path of the second light beam is changed, the second light beam enters the spatial beam combiner 200 at an included angle with the first light beam, and then the second light beam is reflected by the spatial beam combiner 200 and can be inserted into the dead zone of the first light beam. The second light beam reflected by the spatial beam combiner 200 is combined with the first light beam to form continuous and dense light.

The semiconductor laser module of the embodiment of the application can form a light spot energy density graph as shown in fig. 3 on a fast axis; a plot of the spot energy density as shown in figure 5 can be formed on the slow axis. Wherein, the abscissa in fig. 3 and 5 is the spot size in mm; the ordinate is the intensity of light intensity and energy in W/mm²。

Meanwhile, the optical path of the first light beam in the continuous reflector 100 is equal to the optical path of the second light beam entering the spatial beam combiner 200 through the light entrance side 210 of the spatial beam combiner 200, so the optical path difference between the first light beam and the second light beam is zero, i.e. the optical path difference is eliminated. The light spots formed by the light beams after the optical path difference is eliminated have better uniformity and continuity.

In the prior art, in order to eliminate the optical path difference, an optical waveguide is often adopted to recombine a self-space beam combination beam, but a longer path needs to be transmitted in the optical waveguide for eliminating the optical path difference of the combined beam, so that the size of the optical waveguide is large, and the size of the whole optical system is large. The embodiment of the application does not need an optical waveguide for recombining the bundled light beams, and the propagation path of the light beams is short, so that the module is compact in structure and small in size.

In the semiconductor laser module provided by this embodiment, the semiconductor laser array 10 is adopted to emit laser beams, the laser beams include a first beam and a second beam that are parallel to each other, the first beam enters the continuous reflector 100, is folded back by the continuous reflector 100, and then the optical path of the first beam is extended and then is emitted through the spatial beam combiner 200; the second light beam directly enters the spatial beam combiner 200, after passing through the light entrance side 210 of the spatial beam combiner 200, the light path of the second light beam changes, forms an included angle with the first light beam, is reflected by the spatial beam combiner 200, and after being reflected, the second light beam is inserted into the dead zone of the first light beam to form a combined light beam with the first light beam, so that the formed light beam is continuous and dense. Moreover, the optical path of the first light beam in the continuous reflector 100 is equal to the optical path of the second light beam entering the spatial beam combiner 200 through the light entrance side 210 of the spatial beam combiner 200, the optical path difference between the first light beam and the second light beam is zero, the uniformity and the continuity of light spots formed by the light beams after the optical path difference is eliminated are good, and high-quality linear light spots can be output. According to the embodiment of the application, the continuous reflector 100 is used for turning back the first light beam and the space beam combiner 200 is used for changing the light path of the second light beam, the first light beam and the second light beam are combined and emitted, and compared with the mode that the optical path difference is eliminated by reforming and emitting the light beam through the optical waveguide in the conventional combined light beam, the light beam formed by the embodiment of the application is good in quality, short in light propagation path, small in size and compact in structure of a semiconductor laser module, the size of the whole optical system cannot be increased, and the flexible arrangement of other optical elements in the optical system is facilitated.

Specifically, the continuous reflector 100 includes at least three reflective surfaces, and the first light beam is incident to the spatial beam combiner 200 after being reflected by the at least three reflective surfaces in sequence.

After the first light beam enters the reflecting surfaces, the light path of the first light beam is changed, and after the first light beam is continuously reflected by at least three reflecting surfaces in sequence, the light path of the first light beam is prolonged.

Specifically, the reflecting surface may be provided in the form of a mirror, and the optical path after the first light beam is continuously reflected is extended by the mirror. The continuous reflector 100 includes a plurality of first reflecting mirrors 110, and the first light beam is folded back a plurality of times by the plurality of first reflecting mirrors 110 to extend the optical path of the first light beam.

The mutual positions and included angles between the first reflectors 110 may be set according to the optical path of the second light beam, so that the optical path of the first light beam in the continuous reflector 100 is equal to the optical path of the second light beam entering the spatial beam combiner 200 through the light entrance side 210 of the spatial beam combiner 200, so as to eliminate the optical path difference.

Meanwhile, on the premise of eliminating the optical path difference, the mutual positions and included angles of the plurality of first reflecting mirrors 110 are different, and the size of the continuous reflector 100 can be reduced as much as possible, so that the optical path of the first light beam in the continuous reflector 100 is prolonged, and the size of the continuous reflector 100 can be reduced, so as to reduce the size of the whole optical system.

Since the number of the first reflecting mirrors 110 is too small and the optical path of the first light beam is insufficient, the number of the first reflecting mirrors 110 is at least three, and the three first reflecting mirrors 110 turn the first light beam as shown in fig. 7.

The optical path length is the refractive index x the distance traveled by the light beam, and the required optical path length can be specifically calculated according to the formula, so as to set the number, position and included angle of the first reflecting mirrors 110 in the continuous reflector 100.

As shown in fig. 7, when the number of the first reflecting mirrors 110 is three, the continuous reflector 100 includes three first reflecting mirrors 110 respectively fixedly disposed and sequentially reflecting the first light beams, wherein the direction in which the first light beams enter the continuous reflector 100 is the same as the direction in which the first light beams exit the continuous reflector 100.

The first light beam enters the continuous reflector 100 in parallel, passes through the three first reflectors 110 in sequence, and exits in parallel.

As shown in fig. 8, the number of the first reflecting mirrors 110 may also be four, and the continuous reflector 100 includes four first reflecting mirrors 110 respectively fixedly disposed and sequentially reflecting the first light beams, wherein the direction in which the first light beams enter the continuous reflector 100 is the same as the direction in which the first light beams exit from the continuous reflector 100.

The four first reflectors 110 may be disposed at certain positions, such that the first light beam enters the continuous reflector 100 in parallel, sequentially passes through the four first reflectors 110, and exits in parallel.

On the other hand, the reflecting surface can be arranged in a prism mode, and the optical path of the first light beam after continuous turning is prolonged through the sequential turning between a plurality of total reflection surfaces of the prism.

As shown in fig. 6 and 9, in the embodiment of the present application, the special-shaped prism 120 has four total reflection surfaces, the first light beam is totally reflected by the four total reflection surfaces and then turns back four times, and the optical path of the first light beam is equal to the optical path of the second light beam entering the spatial beam combiner 200 through the light entrance side 210 of the spatial beam combiner 200.

Or, the continuous folding is realized by a prism group, one prism group comprises a plurality of prisms, and the plurality of prisms are arranged according to a certain position and angle combination, so that the optical path of the first light beam is prolonged after the first light beam sequentially passes through the plurality of prisms for continuous folding.

The specific arrangement of the reflecting surface in the embodiments of the present application is not limited, and includes but is not limited to the forms of the above-mentioned reflecting mirror, prism, and prism group, and those skilled in the art can arrange the reflecting surface according to specific needs.

For example, as shown in fig. 10, the optical path length can be extended by three turns of three total reflection surfaces. The continuous reflector 100 comprises a special-shaped prism 120 which is provided with a first total reflection surface 121, a second total reflection surface 122 and a third total reflection surface 123 which are used for totally reflecting the first light beam in sequence; wherein the direction in which the first light beam enters the continuous reflector 100 is the same as the direction in which the first light beam exits the continuous reflector 100.

The special-shaped prism 120 includes three total reflection surfaces, a first light beam enters the first total reflection surface 121, is totally reflected by the first total reflection surface 121, and then sequentially exits through the second total reflection surface 122 and the third total reflection surface 123, and the three total reflection surfaces are arranged at a certain position, so that the direction of the first light beam entering the first total reflection surface 121 is the same as the direction of the first light beam exiting from the third total reflection surface 123.

The optical path extension can also be realized by adopting a four-time turning-back mode of four total reflection surfaces. As shown in fig. 9, the continuous reflector 100 includes a profile prism 120 having a first total reflection surface 121, a second total reflection surface 122, a third total reflection surface 123, and a fourth total reflection surface 124 that totally reflect the first light beam in this order; wherein the direction in which the first light beam enters the continuous reflector 100 is the same as the direction in which the first light beam exits the continuous reflector 100.

The special-shaped prism 120 includes four total reflection surfaces, a first light beam enters the first total reflection surface 121, is totally reflected by the first total reflection surface 121, and then sequentially exits through the second total reflection surface 122, the third total reflection surface 123 and the fourth total reflection surface 124, and the direction of the first light beam entering the first total reflection surface 121 is the same as the direction of the first light beam exiting from the fourth total reflection surface 124.

The second light beam is reflected at least twice in the spatial beam combiner 200 and then is output together with the first light beam in an inserting manner.

The initial light emitting directions of the parallel first light beam and the second light beam emitted by the same semiconductor laser array 10 are the same, the second light beam is reflected once in the spatial beam combiner 200, the direction of the second light beam is changed, and after at least one reflection, a combined light beam in the same direction as the first light beam can be formed. The second light beam is reflected at least twice in the spatial beam combiner 200, and the finally reflected second light beam and the first light beam are inserted into the gap of the first light beam in the same direction to form the light beam of the inserted and stitched beam to be emitted.

Preferably, the second light beam is reflected twice in the spatial beam combiner 200 and then exits as an inserted beam with the first light beam. The purpose of inserting and connecting the second light beam with the first light beam can be achieved through two-time reflection of the second light beam, and meanwhile, in the aspect of cost, the number of optical elements used in two-time reflection is small, so that the cost of the semiconductor laser module is low.

Illustratively, as shown in fig. 6, the spatial beam combiner 200 includes a second reflecting mirror 201 and a stripe mirror 202 sequentially disposed along the optical path direction, the stripe mirror 202 is provided with a transmissive stripe region and a reflective stripe region, the first light beam exits through the transmissive stripe region, and the second light beam exits through the reflective stripe region after being reflected by the second reflecting mirror 201.

The second reflecting mirror 201 is disposed at the light incident side 210 of the spatial beam combiner 200, and after the second light beam is totally reflected by the second reflecting mirror 201, the second reflecting mirror 201 changes the optical path of the second light beam, so that the second light beam is incident on the striped mirror 202 in an angle with the first light beam instead of the original parallel incidence.

The stripe mirror 202 is provided with a transmission stripe area and a reflection stripe area, the second light beam enters the reflection stripe area and then is reflected and emitted, the reflected second light beam enters the dead zone of the first light beam through a slot, the first light beam enters the transmission stripe area and then is transmitted and emitted, the first light beam and the second light beam are combined and emitted at the light-emitting side of the stripe mirror 202 to form a combined light beam, the continuity of the light beam is good, and a high-quality linear light spot can be formed.

The spatial combiner 200 may also take the form of a combination of total reflection mirrors and prisms as shown in fig. 11. Specifically, the spatial beam combiner 200 includes a triangular prism 204 and a six-sided prism 203; the included angle of the acute angles of the two adjacent side surfaces of the six-sided prism 203 is 45 °. The first light beams are respectively incident on the incident surfaces of the two triangular prisms 204, and the incident direction is perpendicular to the incident surface of the triangular prism 204, so that the first light beams are not refracted inside the triangular prism 204, and after the first light beams are incident on the incident surface of the triangular prism 204, the first light beams horizontally exit from the exit surface of the six-sided prism 203, and the exit direction is consistent with the incident direction.

After the second light beam vertically enters the six-sided prism 203 and passes through two opposite surfaces of the six-sided prism 203 to be totally reflected for two times, the second light beam is inserted into the first light beam emitted from the upper part and is horizontally emitted together with the first light beam emitted from the upper part in an inserting and empty mode, and a continuous and dense combined light beam is formed. The energy density of the combined light beam is twice of that of the incident light, and the diameter of the combined light beam is half of that of the laser beam, so that the quality and the output power density of the laser beam are improved.

The semiconductor laser module further includes a polarized light group 300 disposed on the light-emitting side of the spatial beam combiner 200, and the polarization state of the combined light beam is adjusted by the polarized light group 300.

Illustratively, the polarization state of the laser beam emitted by the semiconductor laser array 10 is TE linear polarization, the laser beam forms a combined beam after passing through the continuous reflector 100 and the spatial beam combiner 200, the polarization state of the beam is TE linear polarization, and the polarization light group 300 can convert the TE linear polarization into circular polarization.

The circular polarization is added with a layer of phase difference film on the basis of linear polarization, and has the function of enabling deflected light to rotate clockwise and anticlockwise.

Specifically, as shown in fig. 12, the polarization beam set 300 includes a first polarizer 301 and an 1/4 wave plate 302, and the light beam is transmitted through the first polarizer 301 toward the 1/4 wave plate 302.

The first polarizer 301 transmits TE linear polarization, and the light beam is incident on the first polarizer 301 and then transmitted through the first polarizer 301 toward the 1/4 waveplate 302. When the light beam passes through 1/4 waveplate 302, the light beam is converted to circular polarization.

If the circularly polarized light beam meets the processing surface of the back end system, the circularly polarized light beam returns to the system, and after passing through the 1/4 wave plate 302 again, the circularly polarized light beam is converted into TM linear polarization, and the TM linear polarization can affect the emergent laser beam after being reflected to the semiconductor laser array 10.

The light-emitting side of the second polaroid 303 is provided with a light-absorbing plate, the first polaroid 301 and the second polaroid 303 are respectively provided with a polarization reflection film, the first polaroid 301 and the second polaroid 303 are both in TE linear polarization transmission and in TM linear polarization reflection, and the first polaroid 301 and the second polaroid 303 have a reflection effect on TM linear polarization beams, so that the TM linear polarization beams are reflected to the light-absorbing plate to be absorbed after being reflected twice by the first polaroid 301 and the second polaroid 303, and cannot be reflected to the light source to influence the light source.

Therefore, the polarization beam group 300 formed by the first polarizer 301, the second polarizer 303, and the 1/4 wave plate 302 functions to prevent the light beam from affecting and damaging the light source.

In addition, the first polarizer 301 and the second polarizer 303 may be disposed by way of a polarizing film layer, which transmits TE linear polarization and reflects TM linear polarization; the above-described effects can be achieved by providing a polarizing film layer on the lens instead of the first polarizing plate 301 and the second polarizing plate 303.

When the polarizing film is disposed, as shown in fig. 12, the position of the first polarizer 301 is replaced by a lens, the light incident side and the light exit side of the lens are both provided with polarizing films, and TE linear polarization is transmitted through the polarizing film on the light incident side to the 1/4 wave plate 302; the light beam returning to the system from the processing surface of the back-end system is converted into TM linear polarization by the 1/4 wave plate 302, and the TM linear polarization is reflected by the polarizing film layer on the light-emitting side of the lens to the position of the second polarizer 303.

The second polarizer 303 is replaced with another lens having a polarizing film layer on the light incident side to reflect the TM linear polarization and direct it toward the light absorbing plate.

The light-emitting side of the polarized light group 300 is provided with a slow-axis dodging mirror group, and the slow-axis dodging mirror group is used for collimating and homogenizing the light beam in the slow-axis direction.

The slow axis dodging mirror group is used for collimating the light beam in the slow axis direction and then homogenizing the light beam so as to uniformly distribute the light intensity of the light beam and obtain uniform light spots.

The slow-axis dodging lens group comprises at least one positive lens and at least one micro-array lens 401. The positive lens is a lens with thick middle part and thin periphery, and has the capability of converging light, and the positive lens at least comprises a plano-convex lens, a biconvex lens, a concave-convex lens and the like according to the structural form of the positive lens.

The micro-array lens 401 homogenizes the light beam, the micro-array lens 401 is an array formed by lenses with micron-sized clear aperture and relief depth, and the micro-array lens not only has basic functions of focusing, imaging and the like of the traditional lens, but also has the characteristics of small unit size and high integration level, so that the micro-array lens can complete the functions which cannot be completed by the traditional optical element, and can form a plurality of novel optical systems.

The micro-array lens 401 can spatially divide a complete laser wavefront into many tiny portions, each of which is focused by a corresponding lenslet on the focal plane, and a series of micro-lenses can result in a plane consisting of a series of uniform and regular focal points.

As shown in fig. 13, the slow axis dodging mirror group includes a micro array lens 401, a first positive lens 402 and a second positive lens 403 which are arranged in sequence; alternatively, as shown in fig. 14, the slow axis lens group includes a first positive lens 402, a micro array lens 401, and a second positive lens 403, which are disposed in this order. The two groups of different setting orders can realize the collimation and homogenization of the light beams.

The first positive lens 402 and the second positive lens 403 may be slow-axis cylindrical mirrors, which have curvature in the slow-axis dimension and may shape the light beam in one dimension.

As shown in fig. 15, a fast axis adjusting mirror group may be further disposed on the light exit side of the polarization light group 300, and the fast axis adjusting mirror group is used for expanding the beam in the fast axis direction of the light beam and then focusing the beam.

The fast axis adjusting lens group expands the light beam firstly and then focuses the expanded light beam on the fast axis so as to reduce the size of the formed light spot.

Specifically, the fast axis adjusting lens group comprises a beam expanding lens, a collimating lens and a beam shrinking lens which are sequentially arranged, wherein light beams are expanded by the beam expanding lens and then are focused by the beam shrinking lens after being collimated by the collimating lens so as to reduce the size of formed light spots.

The beam expander may be a negative lens 501, and the middle of the lens of the negative lens 501 is thin, and the edge of the lens is thick and is concave, which is also called a concave lens. The negative lens 501 has a diverging function on the light beam, and is also called as a diverging lens. The light beam passing through the negative lens 501 diverges and expands.

The collimating lens can be a third positive lens 502, and the light beam is collimated by the third positive lens 502.

The beam reducing mirror comprises at least one fourth positive lens 503, and the light beam is gradually reduced after passing through the fourth positive lens 503.

The beam reducer further includes a meniscus lens disposed on the light exit side of the fourth positive lens 503. The light beam gradually contracts after passing through the fourth positive lens 503, and then the light beam is contracted to a greater extent by the meniscus lens 504 to be focused on the processing surface, and the meniscus lens 504 is bent toward the light source in the fast axis direction.

Meniscus lens 504 is also used to eliminate spherical aberration, which is one of the aberrations that form a circular diffuse spot on the image plane.

The result of spherical aberration is that after a point is imaged, the point is not a bright point, but a bright spot with a bright edge in the middle and gradually blurred edge, which affects the imaging quality. Therefore, to improve spot quality, spherical aberration needs to be eliminated. According to the embodiment of the application, the meniscus lens 504 is adopted to eliminate spherical aberration, and the effect is good.

The semiconductor laser module that this application embodiment provided needs obtain the facula at the machined surface of specific distance to do benefit to the rear end processing.

Thus, the distance between the beam-reducing mirror and the machining surface is fixed, and then to obtain a spot of a certain size, it is determined by the Rach invariant.

Specifically, nuy ═ n ' y ' u '; wherein n represents the refractive index of the object, u represents the aperture angle of the object, y represents the object height of the object, n ' represents the refractive index of the image, y ' represents the aperture angle of the image, u ' represents the image height of the image, and the parameter of the object is constant, i.e. nuy is a constant.

When a small variation in the image height is desired, the aperture angle becomes large and vice versa, which is the variation in the Rach. The formula is widely applied to optical systems such as optical fiber coupling and light convergence.

With the use of the constant amount of the terahertz, if a small-sized spot is to be obtained, the aperture angle of the image side needs to be increased, and the beam-shrinking mirror formed by the fourth positive lens 503 and the meniscus lens 504 needs to increase the aperture angle of the beam and compress the beam to be smaller, so as to obtain a small spot.

The light spot obtained on the processing surface in the embodiment of the application is an elongated strip line light spot, as shown in fig. 3 and 5, the width of the light spot in one dimension is small, and the width of the light spot in the other dimension is large.

Moreover, when the light-emitting side of the polarized light group 300 is provided with the slow-axis dodging mirror group and the fast-axis adjusting mirror group at the same time, the slow-axis dodging mirror group is located in front of the fast-axis adjusting mirror group, that is, the slow-axis dodging mirror group and the fast-axis adjusting mirror group are sequentially arranged on the light-emitting side of the polarized light group 300.

After passing through the 1/4 wave plate 302, the light beam is firstly subjected to slow collimation and homogenization by the slow axis dodging mirror group, then the light beam is firstly expanded and then focused by the fast axis adjusting mirror group to form contracted light spots, a window mirror 601 is further arranged on the light emergent side of the fast axis adjusting mirror group, and the light beam finally outputs high-quality linear light spots after passing through the window mirror 601.

Furthermore, in order to shorten the size of the semiconductor laser module, a third reflector 701 is further disposed on the main optical path, the third reflector 701 is disposed at an included angle with the direction of the main optical path to change the direction of the light beam passing through the third reflector 701, and after the direction of the light beam is changed, the positions of the optical elements in the semiconductor laser module can be changed to adjust the size of the semiconductor laser module.

The third reflector 701 may be disposed at any position on the main light path as needed, which is not specifically limited in this embodiment of the application.

For example, as shown in fig. 16, a third reflecting mirror 701 is further disposed on the main optical path between the polarized light group 300 and the slow axis dodging mirror group at an included angle, so that the light beam emitted from the polarized light group 300 is reflected by the third reflecting mirror 701 and then enters the slow axis dodging mirror group.

After the light beam of the polarized light group 300 enters the third reflector 701, the light path of the light beam is changed, for example, an angle formed by the third reflector 701 and the main optical axis provided in this embodiment is 45 °, and the light beam passes through the third reflector 701 and is changed from the original horizontal propagation to the vertical propagation, so that the size of the semiconductor laser module is reduced in the horizontal direction, and the size of the semiconductor laser module is further reduced.

The included angle between the third reflector 701 and the main optical axis can be set according to specific requirements, and when the included angles are different, the light paths of the light beams are different, so that the arrangement of each optical element in different optical systems is adapted.

In addition, in order to determine the size and position of the imaging spot on the processing surface, the size and position can be determined by means of early detection. Specifically, a fourth reflector 702 is disposed between the negative lens 501 and the third positive lens 502, a reflection surface of the fourth reflector 702 is away from the light exit surface of the semiconductor laser array 10, and the fourth reflector 702 is configured to receive the detection light beam emitted by the detection light source and reflect the detection light beam toward the processing surface.

Or, a transmission mirror is disposed between the negative lens 501 and the third positive lens 502, a transmission surface of the transmission mirror is away from the light emitting surface of the semiconductor laser array 10, and the transmission mirror is configured to receive the detection light beam emitted from the detection light source and transmit the detection light beam to the light beam processing surface.

The detection light source can be red light, the red light identification degree is high, the red light is reflected or transmitted to the processing surface through the fourth reflecting mirror 702 to form light spots on the processing surface, the size and the position of the light spots formed on the processing surface by the semiconductor laser module are determined according to the size of the light spots formed by the red light, and the size and the position of the desired light spots can be obtained by adjusting the slow-axis dodging mirror group and the fast-axis adjusting mirror group when the semiconductor laser module works formally.

Before the semiconductor laser module works formally, the imaging size and position of the semiconductor laser module are determined through detection of a detection light source and the fourth reflector 702 or the transmission mirror; and starting the semiconductor laser module to work formally after the detection is finished.

For example, a high-pass low-cut film may be disposed on the fourth reflecting mirror 702, so that a light beam with a longer wavelength passes through, a light beam with a shorter wavelength reflects, the wavelength of red light is 605nm, and the wavelength of laser light is above 808nm, when the fourth reflecting mirror 702 is adopted, the high-pass low-cut film may reflect the red light used for detection through the fourth reflecting mirror 702, and the laser beam emitted by the semiconductor laser array 10 is transmitted through the fourth reflecting mirror 702, thereby achieving the effect that detection and operation are not affected by each other.

In summary, in the semiconductor laser module provided in the embodiment of the present application, the semiconductor laser array 10 emits a laser beam, the laser beam is divided into a first beam and a second beam, the first beam enters the continuous reflector 100, is reflected three times or four times at the continuous reflector 100 to complete the extension of the optical path, and enters the transmission stripe region of the stripe mirror 202 of the spatial beam combiner 200 to be directly emitted; the second light beam directly passes through the spatial beam combiner 200, is totally reflected by a second reflecting mirror 201 of the spatial beam combiner 200, and then enters a reflection stripe area of a stripe mirror 202 to be emitted; after the first light beam and the second light beam pass through the spatial slit of the spatial beam combiner 200, the optical paths of the first light beam and the second light beam are equal. The polarization state of the light source of the semiconductor laser array 10 is TE linear polarization, and after rearrangement and beam combination of the continuous reflector 100 and the spatial beam combiner 200, the light source enters the polarization light group 300, the polarization light group 300 includes a first polarization plate 301, a second polarization plate 303, and an 1/4 wave plate 302, the first polarization plate 301 and the second polarization plate 303 are both provided with polarization reflection films, and both polarization reflection films transmit TE linear polarization and reflect TM linear polarization. When the linearly polarized TE laser beam passes through the 1/4 wave plate 302, the light beam is converted into circular polarization, the circularly polarized light beam returns to the system if encountering the rear-end system processing surface, and when encountering the 1/4 wave plate 302 again, the circularly polarized light beam is converted into TM linear polarization, and the first polarizer 301 and the second polarizer 303 have a reflection effect on TM light, so that the TM linear polarized light beam is reflected to the rear-end light-absorbing plate by two reflections without being reflected to the light source to affect the light source; the first polarizer 301 and the second polarizer 303+1/4 wave plate 302 act as anti-reflection light beams to damage the light source, and the second polarizer 303 is arranged to make the semiconductor laser module further have an anti-reflection function to prevent the back end reflected light from reflecting to the light source; the light beams passing through the first polarizer 301 and the second polarizer 303+1/4 wave plate 302 enter a slow-axis dodging mirror group, the slow-axis dodging mirror group is used for conjugate imaging and light spot homogenization, and the imaging (amplification or reduction) of the light source in the slow-axis direction is completed at the rear end, and meanwhile, the light beam homogenization of the slow axis is completed; the light beam passing through the slow axis dodging mirror group enters a fast axis adjusting mirror group, which can also be called as a reverse telephoto adjusting mirror group, the beam expansion is completed firstly, then the fast axis focusing is completed, and finally the light beam is emitted through the window mirror 601, and the high-quality linear light spot is finally output.

The embodiment of the invention also discloses an optical system which comprises the semiconductor laser module.

The optical system can be applied to the fields of laser industrial processing, laser medical cosmetology, detection and the like by utilizing the formed homogenized and high-quality line light spots. And, because of the small structure size of semiconductor laser module for this optical system's overall size is little, can arrange more optical element, in order to adapt to different demands.

The semiconductor laser array 10 of the semiconductor laser module comprises a plurality of stacked and mutually parallel chip bars 11, the chip bars 11 can be laser diode chips, each chip bar 11 is a light-emitting unit, and a group of parallel laser beams can be formed after the plurality of chip bars 11 are stacked and arranged in parallel.

Furthermore, the semiconductor laser module generates heat when emitting laser beams, and in order to reduce the heat of the semiconductor laser module and maintain the performance of the semiconductor laser module, heat dissipation is also required for the semiconductor laser array 10.

Specifically, as shown in fig. 17 and 18, the optical system further includes a plurality of heat sinks 12 stacked and arranged in parallel, the plurality of heat sinks 12 and the plurality of chip bars 11 are arranged at intervals in a one-to-one correspondence manner, and the heat sinks 12 are attached to the corresponding chip bars 11 to dissipate heat of the chip bars 11. The heat generated by the laser beam emitted by the semiconductor laser module is mainly generated by the light emission of the chip bar 11, so that the heat sink 12 is used for dissipating the heat of the chip bar 11, and the purpose of dissipating the heat of the semiconductor laser module is achieved.

In addition, a collimating micro-lens 13 is correspondingly arranged in the light-emitting direction of each chip bar 11, and is used for collimating the light beams emitted from the chip bars 11 to form parallel light beams for emission.

A plurality of heat sinks 12, chip bars 11, and collimating microlenses 13 may form a stacked array structure as shown in fig. 18 and 19, forming a semiconductor laser array 10.

According to different requirements, a plurality of heat sinks 12 and the chip bars 11 with different numbers can be arranged in a stacked mode. Taking fig. 19 as an example, the multiple heat sinks 12, the chip bars 11 and the collimating microlenses 13 stacked in the upper half part form an integral structure, and can emit a first light beam; the heat sinks 12, the chip bars 11 and the collimating micro-lenses 13 laminated on the lower half part form an integral structure and can emit second light beams; thus, the stacked array in fig. 19 can emit the parallel first light beam and the parallel second light beam to meet the requirement of emitting the parallel light beams in the embodiment of the present application, and then the homogenized and high-quality line light spot is obtained through the subsequent optical elements, so that the optical system is applied to the fields of laser industrial processing, laser medical cosmetology, and the like.

The optical system includes the same structure and advantageous effects as the semiconductor laser module in the foregoing embodiment. The structure and the advantageous effects of the semiconductor laser module have been described in detail in the foregoing embodiments, and are not described herein again.

The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. a semiconductor laser module, it is characterized in that, comprise semiconductor laser array, and the continuous reflector and space beam combiner that the laser beam exit direction of described semiconductor laser array is arranged successively, the laser beam of exit comprises the parallel first. A light beam and a second light beam, the first light beam is folded in the continuous reflector and then exits through the spatial beam combiner, the second light beam passes through the light incident side of the spatial beam combiner and the The first light beam is incident on the spatial beam combiner at an included angle, and is reflected by the spatial beam combiner to combine with the first light beam, and the optical path of the first light beam in the continuous reflector is the same as the The optical paths of the second light beam entering the spatial beam combiner through the light incident side of the spatial beam combiner are equal.

2 . The semiconductor laser module according to claim 1 , wherein the continuous reflector comprises at least three reflective surfaces, and the first light beam is reflected by the at least three reflective surfaces in sequence, and then enters the Space combiner.

3 . The semiconductor laser module according to claim 2 , wherein the continuous reflector comprises a first total reflection surface, a second total reflection surface and a third total reflection surface that sequentially total reflect the first beam. 4 . a special-shaped prism on the reflecting surface; or, the continuous reflector includes three first reflecting mirrors that are respectively fixedly arranged and reflect the first light beam in sequence;

Wherein, the direction in which the first light beam enters the continuous reflector is the same as the direction in which the first light beam exits from the continuous reflector.

4 . The semiconductor laser module according to claim 2 , wherein the continuous reflector comprises a first total reflection surface, a second total reflection surface, a third total reflection surface that totally reflect the first beam in sequence. 5 . The special-shaped prisms of the reflection surface and the fourth total reflection surface; or, the continuous reflector includes four first reflection mirrors that are respectively fixedly arranged and reflect the first light beam in sequence;

5 . The semiconductor laser module according to claim 1 , wherein the second beam is reflected at least twice in the spatial beam combiner and then interleaved with the first beam to exit. 6 .

6 . The semiconductor laser module according to claim 1 , further comprising a polarized light group disposed on the light output side of the spatial beam combiner, and the polarized light group adjusts the polarization state of the light beam emitted by the combined beam. 7 .

7 . The semiconductor laser module according to claim 6 , wherein the polarized light group comprises a first polarizer and a 1/4 wave plate arranged in sequence along the direction of the optical path, and the line of the first polarizer passes through the line of the first polarizer. The polarized light is converted to circularly polarized light by the 1/4 wave plate.

8 . The semiconductor laser module according to claim 7 , wherein the polarized light group further comprises a second polarizer parallel to the first polarizer, and a light-emitting side of the second polarizer is provided. There is a light-absorbing plate, the first polarizer is arranged on the main optical path at an included angle, and the laser beam reflected by the processing surface is reflected by the first polarizer and the second polarizer in turn, and then shoots towards the light-absorbing plate .

9 . The semiconductor laser module according to claim 6 , further comprising a slow-axis homogenizing mirror group disposed on the light-emitting side of the polarized light group for collimating and homogenizing the slow-axis direction of the light beam. 10 . .

10 . The semiconductor laser module according to claim 9 , wherein the slow-axis homogenizing mirror group comprises at least one positive lens and at least one microarray lens. 11 .

11. The semiconductor laser module according to claim 10, wherein the slow-axis homogenizing mirror group comprises a first positive lens, a microarray lens and a second positive lens arranged in sequence;

Alternatively, the slow-axis homogenizing lens group includes a microarray lens, a first positive lens and a second positive lens which are arranged in sequence.

12. The semiconductor laser module according to claim 6 or 9, further comprising a fast-axis adjusting mirror group arranged on the light-emitting side of the polarized light group, for focusing after expanding the fast-axis direction of the light beam .

13 . The semiconductor laser module according to claim 12 , wherein the light-emitting side of the polarized light group is provided with a slow-axis uniform light mirror group and a fast-axis adjustment mirror group, and the slow-axis uniform light mirror group is located at 13 . Before the fast-axis adjusting mirror group, the light beam enters the fast-axis adjusting mirror group after passing through the slow-axis uniform light mirror group.

14 . The semiconductor laser module according to claim 12 , wherein the fast-axis adjusting mirror group comprises a beam expander, a collimator, and a beam reducer arranged in sequence. 15 .

15. The semiconductor laser module according to claim 14, wherein the beam expander is a negative lens, the collimator lens is a third positive lens, and the beam reducer includes at least one fourth positive lens .

16 . The semiconductor laser module according to claim 15 , wherein the beam reducing mirror further comprises a meniscus lens, and the meniscus lens is disposed on the light-emitting side of the fourth positive lens. 17 .

17 . The semiconductor laser module according to claim 1 , wherein a third reflector is further provided on the main optical path, and the third reflector is arranged at an angle with the direction of the main optical path to change the optical path. 18 . The direction of the beam of the third mirror.

18. An optical system, characterized by comprising the semiconductor laser module according to any one of claims 1 to 17.