CN111446625A - High-power short-wave semiconductor laser illuminator - Google Patents
High-power short-wave semiconductor laser illuminator Download PDFInfo
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- CN111446625A CN111446625A CN202010349966.1A CN202010349966A CN111446625A CN 111446625 A CN111446625 A CN 111446625A CN 202010349966 A CN202010349966 A CN 202010349966A CN 111446625 A CN111446625 A CN 111446625A
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- short
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- wave semiconductor
- semiconductor laser
- coupler
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- 239000004065 semiconductor Substances 0.000 title claims abstract description 56
- 239000013307 optical fiber Substances 0.000 claims abstract description 49
- 238000005286 illumination Methods 0.000 claims abstract description 29
- 230000017525 heat dissipation Effects 0.000 claims abstract description 6
- 239000000835 fiber Substances 0.000 claims description 10
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 239000010949 copper Substances 0.000 claims description 3
- 238000003384 imaging method Methods 0.000 abstract description 5
- 230000000694 effects Effects 0.000 description 4
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/40—Arrangement of two or more semiconductor lasers, not provided for in groups H01S5/02 - H01S5/30
- H01S5/4025—Array arrangements, e.g. constituted by discrete laser diodes or laser bar
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/02—Structural details or components not essential to laser action
- H01S5/022—Mountings; Housings
- H01S5/0225—Out-coupling of light
- H01S5/02251—Out-coupling of light using optical fibres
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/02—Structural details or components not essential to laser action
- H01S5/024—Arrangements for thermal management
- H01S5/02407—Active cooling, e.g. the laser temperature is controlled by a thermo-electric cooler or water cooling
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/02—Structural details or components not essential to laser action
- H01S5/024—Arrangements for thermal management
- H01S5/02476—Heat spreaders, i.e. improving heat flow between laser chip and heat dissipating elements
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/40—Arrangement of two or more semiconductor lasers, not provided for in groups H01S5/02 - H01S5/30
- H01S5/4012—Beam combining, e.g. by the use of fibres, gratings, polarisers, prisms
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- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Optics & Photonics (AREA)
- Optical Couplings Of Light Guides (AREA)
Abstract
The invention relates to a lighting device, in particular to a high-power short-wave semiconductor laser illuminator. The invention aims to solve the technical problem that the existing short-wave imaging equipment is difficult to realize illumination on objects at night beyond the distance of several kilometers, and provides a high-power short-wave semiconductor laser illuminator. The illuminator comprises M driving power supplies, M radiating fins, N short-wave semiconductor lasers, N laser output optical fibers, a coupler, an illumination output optical fiber, a beam expanding collimating lens and a convection fan; n short-wave semiconductor lasers are divided into M groups; each heat dissipation sheet is provided with a driving power supply and a group of short-wave semiconductor lasers; the output ends of the N short-wave semiconductor lasers are connected with the coupler through N laser output optical fibers, and the N laser output optical fibers at the input end of the coupler are arranged in a central symmetry mode; the coupler is connected with the beam expanding collimating lens through the illumination output optical fiber; the length of the illumination output optical fiber is more than or equal to 200 mm.
Description
Technical Field
The invention relates to a lighting device, in particular to a high-power short-wave semiconductor laser illuminator.
Background
With the continuous development of short wave imaging technology, the application of short wave imaging equipment is more and more extensive. Since the investigation and search activities are usually performed at normal temperature, the object to be detected is imaged by the energy of sunlight reflected by the object to be detected. However, no sunlight is irradiated at night, and lighting equipment is needed for assistance in order to realize imaging, but the power of the conventional short-wave light-emitting chip is limited, so that objects beyond a kilometer distance are difficult to realize illumination.
Disclosure of Invention
The invention aims to solve the technical problem that the existing short-wave imaging equipment is difficult to realize illumination on objects at night beyond the distance of several kilometers, and provides a high-power short-wave semiconductor laser illuminator.
In order to solve the technical problems, the technical solution provided by the invention is as follows:
a high-power short-wave semiconductor laser illuminator is characterized in that: the device comprises M driving power supplies, M radiating fins, N short-wave semiconductor lasers, N laser output optical fibers, a coupler, a lighting output optical fiber, a beam expanding collimating lens and a convection fan, wherein N is more than or equal to 2, and M is more than or equal to 1;
n short-wave semiconductor lasers are divided into M groups;
each heat dissipation sheet is provided with a driving power supply and a group of short-wave semiconductor lasers powered by the driving power supply;
the output ends of the N short-wave semiconductor lasers are connected with the input end of the coupler through N laser output optical fibers, and the N laser output optical fibers at the input end of the coupler are arranged in a central symmetry mode;
the coupler is connected with the beam expanding collimating lens through the illumination output optical fiber;
the M radiating fins are arranged in parallel and in a clearance mode;
the convection fan is arranged on one side of the M radiating fins and used for the convection heat dissipation of the M radiating fins;
all the laser output fibers on each radiating fin are arranged in a coiling manner, and the coiling radius is larger than or equal to the turning radius of the laser output fibers;
the illumination output optical fiber is arranged in a coiling manner, and the coiling radius is larger than or equal to the turning radius of the illumination output optical fiber;
the length of the illumination output optical fiber is more than or equal to 200 mm.
Further, the wavelength of the short-wave semiconductor laser is 1550 nm.
Furthermore, the material of the heat sink is copper or aluminum.
Further, the beam expanding and collimating lens adopts a zoom lens.
Further, N is 19 and M is 3.
Furthermore, 6 and 7 short-wave semiconductor lasers are respectively arranged on the three radiating fins.
Further, the arrangement mode of the N laser output optical fibers at the input end of the coupler is as follows: the center is 1 route, and two circles are arranged from inside to outside by taking the center as the center, the inner circle is 6 routes, and the outer circle is 12 routes.
Compared with the prior art, the invention has the following beneficial effects:
1. the high-power short-wave semiconductor laser illuminator provided by the invention has the advantages that the plurality of short-wave semiconductor lasers are driven to emit light, energy is coupled into one beam by using the optical fiber, and high-power output is finally formed, so that the output energy of the short-wave semiconductor laser illuminator is increased to dozens of times of that of a single short-wave semiconductor laser, namely, the plurality of kilowatt-level short-wave semiconductor lasers are combined into the dozens of kilowatt-level short-wave semiconductor laser illuminator, and finally, the illuminating effect that the short-wave power is not less than 30W and the illuminating can reach several kilometers is achieved, the problems that the conventional short-wave semiconductor laser has small power and is difficult to illuminate objects at distances of several.
2. The short-wave semiconductor laser is used as a light-emitting chip, and the light-emitting chip is small and exquisite in size and convenient to use relative to short-wave solid and short-wave optical fiber lasers.
3. The short-wave semiconductor laser output optical fiber and the coupled illumination output optical fiber are arranged in a coiling mode, and the size of the whole illuminator is further reduced.
4. The coiling radius of the laser output optical fiber and the illumination output optical fiber should not be smaller than the turning radius of the optical fiber so as to prevent light leakage.
5. N laser output optical fibers at the input end of the coupler are arranged in a centrosymmetric mode to ensure the uniformity of light before coupling.
6. The length of the illumination output fiber should be more than or equal to 200mm to ensure that the length of the fiber is enough to homogenize the input light.
7. And a convection fan is arranged on the side of the radiating fin and used for cooling and radiating the driving power supply and the short-wave semiconductor laser, and the radiating effect is improved in an air convection mode.
8. The high-power short-wave semiconductor laser illuminator provided by the invention is mainly used for 1550nm waveband, but not limited to the waveband.
9. The beam expanding collimating lens can be a fixed-focus lens or a zoom lens, and when the zoom lens is adopted, output light can be shaped, so that the light spot size modulation is realized, and the size of an illumination range is controlled.
10. The values of M and N can be adjusted according to the specific volume and weight requirements of the high-power short-wave semiconductor laser illuminator.
Drawings
FIG. 1 is a schematic structural diagram of a high-power shortwave semiconductor laser illuminator of the present invention;
FIG. 2 is a schematic cross-sectional view of 19 laser output fibers at the input end of a coupler arranged in a centrosymmetric manner according to an embodiment of the present invention;
description of reference numerals:
1-driving power supply, 2-short wave semiconductor laser, 3-laser output optical fiber, 4-coupler, 5-lighting output optical fiber, 6-beam expanding collimating lens, 7-radiating fin and 8-convection fan.
Detailed Description
The invention will be further described with reference to the accompanying drawings.
A high-power short-wave semiconductor laser illuminator comprises M driving power supplies 1, M radiating fins 7, N short-wave semiconductor lasers 2, N laser output optical fibers 3, a coupler 4, an illumination output optical fiber 5, a beam expanding collimating lens 6 and a convection fan 8, wherein N is more than or equal to 2, and M is more than or equal to 1; the N short-wave semiconductor lasers 2 are divided into M groups; each radiating fin 7 is provided with a driving power supply 1 and a group of short-wave semiconductor lasers 2 powered by the driving power supply 1; the output ends of the N short-wave semiconductor lasers 2 are connected with the input end of a coupler 4 through N laser output optical fibers 3, and the N laser output optical fibers 3 at the input end of the coupler 4 are arranged in a central symmetry mode (as shown in figure 2); the coupler 4 is connected with the beam expanding collimating lens 6 through the illumination output optical fiber 5, the illumination output optical fiber 5 is connected to the focal plane position of the beam expanding collimating lens 6 through the SMA connector, and the coupled light enters the thicker illumination output optical fiber 5; all the laser output fibers 3 on each radiating fin 7 are arranged in a coiling manner, and the coiling radius is larger than or equal to the turning radius of the laser output fibers 3; the illumination output optical fiber 5 is arranged in a coiling manner, and the coiling radius is larger than or equal to the turning radius of the illumination output optical fiber 5; the length of the illumination output optical fiber 5 is more than or equal to 200mm, so that the length of the optical fiber is enough to homogenize the input light; the M radiating fins 7 are arranged in parallel and in a clearance mode; the convection fan 8 is arranged on one side of the M radiating fins 7 and is used for the convection heat dissipation of the M radiating fins 7; the heat radiating fins 7 are made of metal materials (such as copper and aluminum) with good heat conduction, the heat radiating fins 7 and the convection fan 8 are configured to cool and radiate the driving power supply 1 and the short-wave semiconductor laser 2, and the heat radiating effect is improved in an air convection mode. The high-power short-wave semiconductor laser illuminator can realize the laser illumination function of short wave not less than 30W power and several kilometers. The beam expanding collimating lens 6 can be in a fixed focal length mode and an adjustable focusing mode, the size of a fixed focal length light spot is unchanged, the size of the light spot can be adjusted according to a control instruction in the focusing mode, output light rays are shaped, and the size of the light spot is adjusted according to actual requirements. The high-power short-wave semiconductor laser illuminator provided by the invention is mainly used for 1550nm waveband, but not limited to the waveband.
Examples
The power of the short wave semiconductor laser 2 is 2W, the number is 19, the short wave semiconductor laser is transmitted to the coupler 4 for coupling through 19 paths of laser output optical fibers 3, then the short wave semiconductor laser is output to the beam expanding collimating lens 6 through the illumination output optical fibers 5, the core diameter of the laser output optical fibers 3 is 50 micrometers, the core diameter of the illumination output optical fibers 5 connected with the coupler 4 is 400 micrometers, the beam expanding collimating lens 6 is in an adjustable focusing mode, the focal length of a lens group in the beam expanding collimating lens 6 is adjusted through a motor, the size change of illumination light spots is further realized, the relation adjustment of focal length values, the size of the light spots and the position of the lens group is realized through calibration, the feedback of the focal length and the size of the light spots is realized through a potentiometer feedback mode. The output power of the beam expanding collimator lens 6 can reach more than 30W, and the efficiency is about 0.8. Because 2 are more in quantity of shortwave semiconductor laser, in order to reduce volume and weight, divide into the three-layer installation with it, every number of layers quantity is 6 respectively, 6 and 7, and every layer all is furnished with fin 7, and three fin 7 is parallel and the clearance sets up to realize the air convection through convection fan 8, reach the heat dissipation purpose. The arrangement mode of 19 laser output fibers 3 at the input end of the coupler 4 is as follows: the center is 1 route, and two circles are arranged from inside to outside by taking the center as the center, the inner circle is 6 routes, and the outer circle is 12 routes.
Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same, and it is obvious for a person skilled in the art to modify the specific technical solutions described in the foregoing embodiments or to substitute part of the technical features, and these modifications or substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions protected by the present invention.
Claims (7)
1. A high-power shortwave semiconductor laser illuminator is characterized in that: the device comprises M driving power supplies (1), M radiating fins (7), N short-wave semiconductor lasers (2), N laser output optical fibers (3), a coupler (4), a lighting output optical fiber (5), a beam expanding collimating lens (6) and a convection fan (8), wherein N is more than or equal to 2, and M is more than or equal to 1;
n short-wave semiconductor lasers (2) are divided into M groups;
each radiating fin (7) is provided with a driving power supply (1) and a group of short-wave semiconductor lasers (2) powered by the driving power supply (1);
the output ends of the N short-wave semiconductor lasers (2) are connected with the input end of the coupler (4) through N laser output optical fibers (3), and the N laser output optical fibers (3) at the input end of the coupler (4) are arranged in a centrosymmetric mode;
the coupler (4) is connected with a beam expanding collimating lens (6) through an illumination output optical fiber (5);
the M radiating fins (7) are arranged in parallel and in a clearance mode;
the convection fan (8) is arranged on one side of the M radiating fins (7) and is used for the convection heat dissipation of the M radiating fins (7);
all the laser output fibers (3) on each radiating fin (7) are arranged in a coiling manner, and the coiling radius is larger than or equal to the turning radius of the laser output fibers (3);
the illumination output optical fiber (5) is arranged in a coiling manner, and the coiling radius is larger than or equal to the turning radius of the illumination output optical fiber (5);
the length of the illumination output optical fiber (5) is more than or equal to 200 mm.
2. The high-power short-wave semiconductor laser illuminator of claim 1, wherein: the wavelength of the short-wave semiconductor laser (2) is 1550 nm.
3. The high-power short-wave semiconductor laser illuminator of claim 1, wherein: the radiating fins (7) are made of copper or aluminum.
4. The high-power short-wave semiconductor laser illuminator of claim 1, wherein: the beam expanding collimating lens (6) adopts a zoom lens.
5. The high-power short-wave semiconductor laser illuminator of any one of claims 1 to 4, wherein: the N is 19, and the M is 3.
6. The high-power short-wave semiconductor laser illuminator of claim 5, wherein: and 6, 6 and 7 short-wave semiconductor lasers (2) are respectively arranged on the three radiating fins (7).
7. The high-power short-wave semiconductor laser illuminator of claim 6, wherein: the arrangement mode of 19 laser output optical fibers (3) at the input end of the coupler (4) is as follows: the center is 1 route, and two circles are arranged from inside to outside by taking the center as the center, the inner circle is 6 routes, and the outer circle is 12 routes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010349966.1A CN111446625A (en) | 2020-04-28 | 2020-04-28 | High-power short-wave semiconductor laser illuminator |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010349966.1A CN111446625A (en) | 2020-04-28 | 2020-04-28 | High-power short-wave semiconductor laser illuminator |
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| Publication Number | Publication Date |
|---|---|
| CN111446625A true CN111446625A (en) | 2020-07-24 |
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| CN202010349966.1A Pending CN111446625A (en) | 2020-04-28 | 2020-04-28 | High-power short-wave semiconductor laser illuminator |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004043981A (en) * | 2002-07-08 | 2004-02-12 | Fuji Photo Film Co Ltd | Apparatus for bleaching treatment |
| US20040247240A1 (en) * | 2003-03-25 | 2004-12-09 | Fuji Photo Film Co., Ltd. | Method for adjusting alignment of laser beams in combined-laser-light source where the laser beams are incident on restricted area of light-emission end face of optical fiber |
| CN1644189A (en) * | 2005-01-20 | 2005-07-27 | 中国科学院上海光学精密机械研究所 | Semiconductor laser alignment coupler |
| CN104075211A (en) * | 2014-06-24 | 2014-10-01 | 华南理工大学 | Optical structure of automotive laser high-beam light |
| US20160254642A1 (en) * | 2015-02-26 | 2016-09-01 | Fanuc Corporation | Air-cooled laser device having l-shaped heat-transfer member with radiating fins |
| CN211958246U (en) * | 2020-04-28 | 2020-11-17 | 中国科学院西安光学精密机械研究所 | High-power short-wave semiconductor laser illuminator |
-
2020
- 2020-04-28 CN CN202010349966.1A patent/CN111446625A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004043981A (en) * | 2002-07-08 | 2004-02-12 | Fuji Photo Film Co Ltd | Apparatus for bleaching treatment |
| US20040247240A1 (en) * | 2003-03-25 | 2004-12-09 | Fuji Photo Film Co., Ltd. | Method for adjusting alignment of laser beams in combined-laser-light source where the laser beams are incident on restricted area of light-emission end face of optical fiber |
| CN1644189A (en) * | 2005-01-20 | 2005-07-27 | 中国科学院上海光学精密机械研究所 | Semiconductor laser alignment coupler |
| CN104075211A (en) * | 2014-06-24 | 2014-10-01 | 华南理工大学 | Optical structure of automotive laser high-beam light |
| US20160254642A1 (en) * | 2015-02-26 | 2016-09-01 | Fanuc Corporation | Air-cooled laser device having l-shaped heat-transfer member with radiating fins |
| CN211958246U (en) * | 2020-04-28 | 2020-11-17 | 中国科学院西安光学精密机械研究所 | High-power short-wave semiconductor laser illuminator |
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