CN117913652A - Self-collimation external cavity semiconductor laser based on concave grating - Google Patents
Self-collimation external cavity semiconductor laser based on concave grating Download PDFInfo
- Publication number
- CN117913652A CN117913652A CN202410086236.5A CN202410086236A CN117913652A CN 117913652 A CN117913652 A CN 117913652A CN 202410086236 A CN202410086236 A CN 202410086236A CN 117913652 A CN117913652 A CN 117913652A
- Authority
- CN
- China
- Prior art keywords
- semiconductor laser
- concave grating
- external cavity
- laser
- grating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000004065 semiconductor Substances 0.000 title claims abstract description 73
- 239000000919 ceramic Substances 0.000 claims description 11
- 239000003822 epoxy resin Substances 0.000 claims description 4
- 239000003292 glue Substances 0.000 claims description 4
- 229920000647 polyepoxide Polymers 0.000 claims description 4
- 230000010354 integration Effects 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000001093 holography Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 238000004611 spectroscopical analysis Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Abstract
The self-collimation external cavity semiconductor laser based on the concave grating is characterized in that the concave grating for diffracting laser beams is positioned in front of a semiconductor laser tube for outputting the laser beams, so that the laser beams passing through the concave grating are changed into parallel light, zero-order diffracted light after being diffracted by the concave grating is used as output light to be output, and feedback is formed between the first-order diffraction and the semiconductor laser tube. The advantages are that: the use of element collimating lenses for the traditional grating laser is reduced, so that the size of the laser is reduced, the structural stability and compactness of the laser are improved, and the integration and miniaturization of the laser are facilitated.
Description
Technical Field
The invention relates to an auto-collimation external cavity semiconductor laser based on a concave grating.
Background
The external cavity semiconductor laser has the advantages of high coherence, low phase frequency noise, high monochromaticity, wide wavelength tuning capability and the like, and is applied to various fields such as spectroscopy, metrology, biomedicine, holography, space laser communication, laser radar, coherent detection and the like.
The external cavity semiconductor laser includes a semiconductor laser light source portion and an external cavity portion. The light source part is a semiconductor laser tube, which is used as a gain medium and determines the laser wavelength range. The external cavity is used as a frequency selection unit, the output light of the semiconductor laser is fed back through the external cavity, and only light with specific wavelength can return to the active area to interact with the internal light field, so that the line width is reduced, and the phase noise and the intensity noise of the laser are reduced. External feedback elements are of a wide variety, such as diffraction gratings, fiber Bragg Gratings (FBGs) and Fabry-Perot (F-P) cavities, and combinations of these elements.
The most commonly used grating feedback external cavity structure in external cavity semiconductor lasers is the Littrow or Littman structure, as shown in fig. 4 and 5. In the Littrow structure, laser emitted by a semiconductor laser tube chip is collimated by a lens, then enters a diffraction grating to be diffracted, zero-order light is output as output light, and first-order light returns to the semiconductor laser tube along an original path to form a resonant cavity. By rotating and translating the diffraction grating, the output wavelength of the laser can be changed, thereby achieving wavelength tuning. In the Littman structure, the collimated laser is diffracted to the reflector after passing through the fixed diffraction grating with an adjusted angle, and the reflected light returns to the grating again to generate secondary diffraction and form feedback with the semiconductor laser tube. By rotating and translating the mirror, the output wavelength of the laser can be changed, thereby achieving wavelength tuning. In comparison, the Littrow laser has a relatively simple structure, high output power, wide tunable range and low cost, but the direction of the output light changes along with the rotation of the diffraction grating. The Littman structure has the advantages of complex structure, relatively low output power and high cost, as the reflector is added, the cavity length is longer, the output linewidth is narrower, and the output light direction is kept unchanged.
2019 Wang Yan et al prepared a widely tunable External Cavity Diode Laser (ECDL) with an ultra high Side Mode Suppression Ratio (SMSR), and the result shows that in Littrow configuration, the performance of the external cavity laser can be improved by increasing the groove density of the grating, and when a 65l/mm grating with a first order diffraction efficiency of 91% is used in an external cavity laser system, the maximum SMSR can reach 209dB, and the tunable range is 209.9nm.
In 2023, cheng Liwen and the like design a narrow linewidth external cavity tunable semiconductor laser based on a Littman structure by adopting a mechanically-engraved blazed grating as an external cavity feedback element, so that the laser output with a wide tuning range of 1480-1580nm and no mode jump and a linewidth of less than 98.27kHz is realized.
Although the laser based on Littrow or Littman structure has been optimized in recent years, the performance has been improved a lot, but there are still some unsolved problems. (1) Semiconductor lasers based on Littrow or Littman structures use a number of discrete components, thus increasing mechanical and material costs while also resulting in relatively low structural stability of the laser; (2) The quality of laser feedback greatly influences the performance of the laser, so that higher requirements are put on a mechanical structure and an adjusting mode of a structural member, and meanwhile, the installation difficulty is greatly increased; (3) The wavelength of the laser is extremely sensitive to the external environment, and the aging of the fixing device, the mechanical vibration and the loose fixing device are extremely easy to cause the vibration of the mode in the resonant cavity, so that the stability of the wavelength of the laser is affected.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provides an auto-collimation external cavity semiconductor laser based on a concave grating.
In order to achieve the above purpose, the present invention adopts the following technical scheme: the self-collimation external cavity semiconductor laser based on the concave grating comprises a semiconductor laser tube and the concave grating, and is characterized in that: the front position of the semiconductor laser tube is provided with a concave grating which enables the laser beam passing through the concave grating to be parallel, zero-order diffraction light diffracted by the concave grating is used as output light to be output, and feedback is formed between the first-order diffraction and the semiconductor laser tube.
Further, the laser diode laser device further comprises a reflector, wherein the reflector is arranged on the advancing route of the first-order diffraction light, the first-order diffraction light passes through the reflector and is reflected to the concave grating to carry out secondary diffraction, and feedback is formed between the reflector and the semiconductor laser tube.
Further, the piezoelectric mirror also comprises piezoelectric ceramics, and the piezoelectric ceramics are arranged on the back surface of the reflecting mirror.
Further, the reflector and the piezoelectric ceramic are bonded together through epoxy resin glue.
Further, the mirror is connected with the tunable device for real rotation and translation.
Further, the tunable device is driven by a stepper motor, a micro-electromechanical system.
Further, the precise temperature and flow control device for ensuring the continuous and stable operation of the laser is also included.
Further, the mirror reflection wavelength range is selected according to the laser wavelength.
The beneficial effects of the invention are as follows: it is proposed to use a curved diffraction grating as a feedback element of a semiconductor laser, and to achieve focusing, diffraction and mode selection of the laser light simultaneously with only a single element. The laser device realized by the invention reduces the use of the element collimating lens of the traditional grating laser device, thereby reducing the volume of the laser device, increasing the structural stability and the compactness of the laser device and being beneficial to the integration and the miniaturization of the laser device; meanwhile, the invention has wide application range, can be suitable for various lasers based on Littrow or Littman structures, and can carry out large-range tuning on the wavelength of the laser under the condition of ensuring the linewidth performance of the laser.
Drawings
Fig. 1 is a schematic structural diagram of embodiment 1.
Fig. 2 is a schematic structural view of embodiment 2 of the present application.
Fig. 3 is a schematic structural view of embodiment 3 of the present application.
Fig. 4 is a schematic diagram of a prior art Littrow structure.
Fig. 5 is a schematic diagram of a Littman structure of the prior art.
Detailed Description
The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to fig. 1 to 5 of the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments.
Example 1: the self-collimation external cavity semiconductor laser based on the concave grating comprises a semiconductor laser tube 1 and a concave grating 2, wherein the concave grating for diffracting laser beams is positioned in front of the semiconductor laser tube for outputting the laser beams, so that the laser beams passing through the concave grating are changed into parallel light, zero-order diffracted light after being diffracted by the concave grating is used as output light to be output, and feedback is formed between first-order diffraction and the semiconductor laser tube.
The self-collimation external cavity semiconductor laser based on the concave grating further comprises a precise temperature control and flow control device for ensuring continuous and stable operation of the laser.
The self-collimation external cavity semiconductor laser based on the concave grating is characterized in that the concave grating 2 is placed at a proper distance from a semiconductor laser tube, so that laser beams passing through the concave grating 2 are parallel light.
The self-collimation external cavity semiconductor laser based on the concave grating is characterized in that a semiconductor laser tube 1 is used for outputting laser beams, the concave grating 2 diffracts the incident laser beams, meanwhile, the concave grating 2 collimates the laser beams, zero-order diffracted light diffracted by the concave grating 2 is used as output light to be output, and feedback is formed between first-order diffraction and the semiconductor laser tube.
Example 2: the self-collimation external cavity semiconductor laser based on the concave grating comprises a semiconductor laser tube and the concave grating, wherein the concave grating used for diffracting laser beams is positioned in front of the semiconductor laser tube used for outputting the laser beams, so that the laser beams passing through the concave grating are changed into parallel light, zero-order diffracted light diffracted by the concave grating is output as output light, feedback is formed between first-order diffraction and the semiconductor laser tube, the self-collimation external cavity semiconductor laser further comprises a reflector, the reflector is arranged on the advancing route of the first-order diffracted light, the first-order diffracted light is reflected to the concave grating to be diffracted secondarily through the reflector, and feedback is formed between the reflector and the semiconductor laser tube.
An auto-collimation external cavity semiconductor laser based on a concave grating, and a reflecting mirror is connected with a tunable device to realize rotation and translation.
The self-collimating external cavity semiconductor laser based on concave grating has tunable device driven by step motor and micro electromechanical system.
The self-collimation external cavity semiconductor laser based on the concave grating further comprises a precise temperature control and flow control device for ensuring continuous and stable operation of the laser.
An auto-collimation external cavity semiconductor laser based on a concave grating, wherein the reflecting wavelength range of a reflecting mirror is selected according to the wavelength of the laser.
The first-order diffraction light of the self-collimation external cavity semiconductor laser based on the concave grating is reflected to the concave grating 2 through the reflector 3 to carry out secondary diffraction, and feedback is formed between the reflector and the semiconductor laser tube. The existence of the reflecting mirror makes the laser diffract secondarily and increases the cavity length of the outer cavity, so that the linewidth of the laser is narrowed and the output performance of the laser is improved. The mirror can translate and rotate through the tunable device, so that the wavelength can be adjusted through adjusting the mirror, thereby realizing wavelength tunability.
Unlike standard diffraction gratings, concave gratings have curved shapes and grating teeth of different profiles. The light output by the laser diode is diffracted by the concave grating, zero-order light generated by the first diffraction of the blazed grating is used as laser to be output, and the output laser is collimated into parallel light by the concave grating. The first-order diffraction light is incident on the plane mirror, and as known from the grating equation d (sin alpha+sin beta) =mλ (where alpha is an incident angle and beta is a diffraction angle), the output light wavelength changes along with the diffraction angle, only the light wave perpendicular to the reflecting mirror returns the original path to the diffraction grating, diffraction occurs again, the original path returns to the diode along the path of the first incident grating, the diode and the reflecting mirror form a new resonant cavity, spatially distributed monochromatic light with each wavelength, and only the light wave meeting the above optical path geometrical relationship can form oscillation in the new resonant cavity, so that the wavelength tuning of the external cavity laser is realized by changing the angle of the reflecting mirror.
Example 3: the self-collimation external cavity semiconductor laser based on the concave grating comprises a semiconductor laser tube and the concave grating, wherein the concave grating used for diffracting laser beams is positioned in front of the semiconductor laser tube used for outputting the laser beams, so that the laser beams passing through the concave grating are changed into parallel light, zero-order diffracted light after being diffracted by the concave grating is output as output light, feedback is formed between first-order diffraction and the semiconductor laser tube, the self-collimation external cavity semiconductor laser further comprises a reflector, a reflector is arranged on the advancing route of the first-order diffracted light, the first-order diffracted light is reflected to the concave grating for secondary diffraction through the reflector, and feedback is formed between the reflector and the semiconductor laser tube; the back of the reflector is provided with piezoelectric ceramics.
The self-collimation external cavity semiconductor laser based on concave grating has reflector and piezoelectric ceramic adhered together with epoxy resin glue.
An auto-collimation external cavity semiconductor laser based on a concave grating, and a reflecting mirror is connected with a tunable device to realize rotation and translation.
The self-collimating external cavity semiconductor laser based on concave grating has tunable device driven by step motor and micro electromechanical system.
The self-collimation external cavity semiconductor laser based on the concave grating further comprises a precise temperature control and flow control device for ensuring continuous and stable operation of the laser.
An auto-collimation external cavity semiconductor laser based on a concave grating, wherein the reflecting wavelength range of a reflecting mirror is selected according to the wavelength of the laser.
In the implementation of the self-collimation external cavity semiconductor laser based on the concave grating, the reflecting mirror 3 and the piezoelectric ceramic 4 are bonded together by using epoxy resin glue, so that the structural stability of the laser is enhanced. The light output by the semiconductor laser tube 1 is collimated and diffracted by the concave grating 2, the zero-order diffracted light of the first diffraction is taken as output light, the first-order diffracted light is diffracted to the reflector 3, and the first-order diffracted light is reflected to the concave grating 2 to generate second diffraction, and feedback is formed between the reflector and the semiconductor laser tube 1. The angle and the position of the reflecting mirror 3 are adjusted through the tunable device, so that the wavelength of the laser can be changed, in addition, the piezoelectric ceramic 4 is bonded with the reflecting mirror 3, the external cavity length can be changed and the wavelength can be changed through changing the voltage of the piezoelectric ceramic 4, and therefore, besides the reflecting mirror 3, the wavelength of the laser can be finely adjusted through adjusting the piezoelectric ceramic 4.
The present invention is not limited to the above-mentioned embodiments, and any person skilled in the art, based on the technical solution of the present invention and the inventive concept thereof, can be replaced or changed within the scope of the present invention.
Claims (8)
1. The self-collimation external cavity semiconductor laser based on the concave grating comprises a semiconductor laser tube and the concave grating, and is characterized in that: the front position of the semiconductor laser tube is provided with a concave grating which enables the laser beam passing through the concave grating to be parallel, zero-order diffraction light diffracted by the concave grating is used as output light to be output, and feedback is formed between the first-order diffraction and the semiconductor laser tube.
2. The concave grating-based self-collimating external cavity semiconductor laser of claim 1, wherein: the semiconductor laser tube also comprises a reflector, wherein the reflector is arranged on the advancing route of the first-order diffraction light, the first-order diffraction light is reflected to the concave grating to carry out secondary diffraction through the reflector, and feedback is formed between the reflector and the semiconductor laser tube.
3. The concave grating-based self-collimating external cavity semiconductor laser of claim 2, wherein: the piezoelectric ceramic is arranged on the back of the reflecting mirror.
4. A concave grating based auto-collimation external cavity semiconductor laser as in claim 3, wherein: the reflector and the piezoelectric ceramic are bonded together through epoxy resin glue.
5. The concave grating-based self-collimating external cavity semiconductor laser of claim 2, wherein: the mirror is connected with the tunable device for real rotation and translation.
6. The concave grating-based self-collimating external cavity semiconductor laser of claim 2, wherein: the tunable device is driven by a stepper motor, a microelectromechanical system.
7. The concave grating-based self-collimating external cavity semiconductor laser of claim 2, wherein: the precise temperature and flow control device for ensuring the continuous and stable operation of the laser is also included.
8. The concave grating-based self-collimating external cavity semiconductor laser of claim 2, wherein: the mirror reflection wavelength range is selected according to the laser wavelength.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410086236.5A CN117913652A (en) | 2024-01-22 | 2024-01-22 | Self-collimation external cavity semiconductor laser based on concave grating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410086236.5A CN117913652A (en) | 2024-01-22 | 2024-01-22 | Self-collimation external cavity semiconductor laser based on concave grating |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117913652A true CN117913652A (en) | 2024-04-19 |
Family
ID=90681706
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410086236.5A Pending CN117913652A (en) | 2024-01-22 | 2024-01-22 | Self-collimation external cavity semiconductor laser based on concave grating |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117913652A (en) |
-
2024
- 2024-01-22 CN CN202410086236.5A patent/CN117913652A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7636376B2 (en) | Method and apparatus for wavelength tuning laser diodes | |
| EP2805389B1 (en) | Wavelength -tunable external cavity laser diode with a grism for oct | |
| US6829258B1 (en) | Rapidly tunable external cavity laser | |
| JP5747355B2 (en) | External cavity laser | |
| US5579327A (en) | External-cavity tunable wavelength light source using semiconductor laser having phase adjustment area | |
| US7822081B2 (en) | Resonator | |
| US6690709B2 (en) | Device and method for reduction of spontaneous emission from external cavity lasers | |
| JP2007234916A (en) | Tunable laser source and method for adjusting its parameter | |
| CN117913652A (en) | Self-collimation external cavity semiconductor laser based on concave grating | |
| CN111129951A (en) | Wide-tuning external cavity semiconductor laser cavity based on grating and MEMS (micro-electromechanical systems) reflector | |
| JP7457723B2 (en) | External cavity laser device, corresponding system and method | |
| CN113036599B (en) | Method for improving output power of Littman structure tunable external cavity semiconductor laser | |
| CN113851921B (en) | Dual-wavelength laser output device and method and semiconductor laser | |
| CN115117732A (en) | Semiconductor laser with tunable external cavity | |
| WO2022127138A1 (en) | Resonant cavity, laser, and laser radar | |
| KR20040051319A (en) | variable wavelength semiconductor laser diode | |
| CN115603172B (en) | Fast tuning small Littman structure external cavity laser | |
| Moser et al. | A novel tunable diode laser using volume holographic gratings | |
| WO2023118949A1 (en) | Narrow linewidth and frequency tunable cat-eye external cavity diode lasers | |
| US8284813B2 (en) | F-P cavity and laser using said F-P cavity | |
| KR20220089097A (en) | Laser package module | |
| CN115360586A (en) | Grating laser based on pyramid array external cavity reflector | |
| Cai et al. | MEMS tunable dual-wavelength laser with large tuning range | |
| WO2002047222A1 (en) | Device and method for reduction of spontaneous emission from external cavity laser | |
| JP2013004769A (en) | Multi-mode wavelength sweeping light source |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination |