CN110459958B - High-power semiconductor laser array wavelength locking and linewidth compressing device and method - Google Patents
High-power semiconductor laser array wavelength locking and linewidth compressing device and method Download PDFInfo
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- H01S5/00—Semiconductor lasers
- H01S5/005—Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping
- H01S5/0071—Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping for beam steering, e.g. using a mirror outside the cavity to change the beam direction
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- H01S5/00—Semiconductor lasers
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- H01S5/00—Semiconductor lasers
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Abstract
The device comprises a semiconductor laser array, a beam shaping system, a partial reflector and a dispersion optical element. And the laser emitted by each bar of the semiconductor laser array is collimated by a corresponding beam shaping system and then is output in parallel. The parallel laser beams respectively enter corresponding partial reflectors, one part of the laser beams are reflected by the corresponding partial reflectors and then sequentially reflected by other partial reflectors behind the reflecting light path and finally enter the dispersive optical element, 1 the diffracted light returns along the original path, the diffracted light is respectively and again incident into each bar of the semiconductor laser array through the reflection of the partial reflectors, and each bar, the corresponding beam shaping system of each bar, the partial reflectors and the dispersive optical element form an external cavity structure together. The method can ensure the strict consistency of the emergent wavelengths of different luminous sources, and is easy to realize accurate wavelength locking and ultra-narrow linewidth spectrum output.
Description
Technical Field
The invention belongs to the technical field of lasers, and particularly relates to a novel high-power semiconductor laser array wavelength locking and linewidth compressing device and method.
Background
The semiconductor laser has important application in the fields of industry, national defense, scientific research, medical treatment and the like by high electro-optic conversion efficiency (usually more than or equal to 60%), light and compact volume structure, wide band coverage (0.6-2 um) and expandable high power output capability (kW-100 kW).
The wavelength of the laser emitted by the conventional semiconductor laser has a certain deviation (+/-3 nm) from the nominal, the center wavelength can drift along with the change of the driving current and the temperature, the typical emission spectrum line width is 3-5nm (FWHM) in the range of 0.2-0.3 nm/A (nm/K), and the index can generally meet the application requirements of most fields. At the same time, many emerging and leading-edge developments have placed more stringent demands on the spectral characteristics of semiconductor lasers. In the field of milliwatt-level to watt-level low-power semiconductor laser aiming at a single-light-emitting source, relatively mature wavelength locking and line width compression technologies are mastered, and are successfully applied to various fields of quantum optics, laser spectroscopy and the like.
In contrast, the wavelength locking and line width compression requirements of high-power semiconductor stacks (stacks) for kilowatt and above are gradually raised in recent years, and the related technology is also far from mature. High-energy semiconductor pump atomic gas lasers, as represented by alkali metal lasers, require that the emission wavelength of kilowatt-level semiconductor pump lasers be precisely aligned to the atomic absorption line (wavelength tolerance ± 0.05 nm) and have extremely narrow spectral linewidths (< 0.1nm, fwhm). Similar demanding requirements are also put on high power semiconductor lasers in hyperpolarized gas pulmonary magnetic resonance imaging to achieve efficient spin polarized optical pumping. Even in the traditional solid state and fiber laser pumping arts, it is desirable for high power semiconductor lasers to have as small a current and temperature wavelength drift coefficient as possible to ensure stable and efficient operation of the overall laser system.
In view of the above requirements, different wavelength locking and linewidth compression methods for high-power semiconductor stacked arrays are sequentially proposed, and the basic principle of the method is that an external cavity is formed by using a dispersive optical element and a semiconductor gain medium to realize effective spectrum regulation. Depending on the dispersive optical element used, it can be classified into two types of external cavity structures, either plane grating based or bulk grating based.
For the surface grating external cavity method, a typical Littrow external cavity structure is directly applied to a semiconductor array in early days, and the power loss ratio is too large and can only be applied to the level of ten to hundred watts although partial expected effects are achieved. Based on this, the company Xemed in the united states proposes a technical solution with high external cavity efficiency and oriented to high power applications, and plans to realize the application of 3kW of narrow linewidth (< 0.1 nm) semiconductor laser to the efficient pumping of alkali metal atoms recently, which has a smart and reasonable structure that is expected, but is complex, too precise, bulky, and has an undefined power expansibility.
For the bulk grating (Volume Bragg Grating, VBG) external cavity method, it is the current mainstream scheme because of its combination of high external cavity efficiency, simple and compact structure and narrow spectral (< 0.1 nm) output characteristics, and the germany DILAS company uses this scheme to achieve 780.2nm laser output with a power of 1kW and a linewidth of 0.08nm (FWHM) on a semiconductor stack of 15 bars. However, while this approach achieves good spectral characteristics, its drawbacks are also significant: firstly, each bar on the semiconductor stacked array needs to be provided with a body grating, and the cost is quite high. And secondly, each individual grating needs to be subjected to independent accurate temperature control so as to have consistent diffraction wavelength, thereby ensuring that each bar emits laser with the same central wavelength. The structure greatly increases the complexity of the system and severely restricts the power expansion capability.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention provides a high-power semiconductor laser array wavelength locking and line width compressing device and method. According to the invention, through reasonable optical system design and utilization of a block grating, wavelength locking and linewidth compression of the high-power semiconductor stacked array with the dopa can be realized, and compared with the existing scheme, the spectrum regulation quality can be further improved, the cost is effectively saved, and the high-power expansion capability is remarkably improved.
In order to achieve the technical purpose of the invention, the following technical scheme is adopted:
a high-power semiconductor laser array wavelength locking and linewidth compressing device comprises a semiconductor laser array, a beam shaping system, a partial reflector and a dispersion optical element.
The semiconductor laser array comprises n bars distributed in a one-dimensional array, namely a1 st bar and a2 nd bar … th bar in sequence, wherein n is more than or equal to 2; the laser emitted by each bar is respectively and sequentially input into a corresponding beam shaping system and a partial reflector, the partial reflectors corresponding to the 1 st bar and the 2 nd bar … th bar are respectively a1 st partial reflector and a2 nd partial reflector … … nth partial reflector, the n partial reflectors are distributed in a one-dimensional array, and the emission light paths of the n partial reflectors are on the same straight line; the dispersive optical element is disposed on the reflected light path of the nth partial mirror.
The n laser beams are respectively collimated by the corresponding beam shaping systems, so that parallel output of the laser beams is realized. The parallel laser beams output from each beam shaping system are respectively incident to the corresponding partial reflectors, one part of the laser beams are reflected by the corresponding partial reflectors, then sequentially reflected by other partial reflectors following the reflecting light path and finally incident to the dispersion optical element, the other part of the laser beams are transmitted out through the partial reflectors, and the transmitted light is the final output laser of the semiconductor. The diffracted light of the dispersive optical element returns along the original path, and is respectively and again incident into each bar of the semiconductor laser array through the reflection of each partial reflector, and each bar, a beam shaping system corresponding to each bar, a partial reflector and the dispersive optical element form an external cavity structure.
Further, the temperature of the dispersive optical element needs to be controlled to precisely lock the central wavelength of the whole spectrum output by the semiconductor laser array, the temperature control mode can be heating or refrigerating, and the temperature control element can be resistance or TEC and the like. The adjustment of the emergent laser power at the corresponding positions of each bar can be realized by designing the reflectivity R i of each partial reflector.
Preferably, n bars in the semiconductor laser array of the present invention are arranged in a vertical stack or a horizontal stack, and the pitches between the bars are equal. If n bars are vertically stacked, the 1 st bar, the 2 nd bar … … th bar, the n groups of beam shaping systems and the n partial reflectors are all arranged in a one-dimensional array from top to bottom. If n bars are stacked horizontally, the 1 st bar, the 2 nd bar … … th bar, the n groups of beam shaping systems and the n partial reflectors are all arranged in a one-dimensional array from left to right. Further, the reflectivity of the partial reflector of the present invention varies from one bar to another. The adjustment of the emergent laser power at the corresponding positions of each bar can be realized by reasonably setting the reflectivity R i of each partial reflector. For example, the reflectances R i of the partial mirrors may be distributed in such a way that R i =1/i, i=1, 2..n, i.e., the reflectance R 1 of the 1 st partial mirror is 100%, the reflectance of the 2 nd partial mirror is 50%, the reflectance of the 3 rd partial mirror is 33%, … …, and the reflectance of the n-th partial mirror is 1/n. Let the free-running output power of each bar be P (typically on the order of-100W). Since the reflectivity R 1 of the 1 st partial mirror is 100%, the 1 st bar has no corresponding outgoing laser light. In addition to no emitted laser light at the 1 st bar position, for the 2 nd bar, the emitted laser power P i at the respective corresponding positions of the 3 rd bar … … n bar isThe reflectance R i =1/i can be calculated as: p i = P, i = 2,3,..n, i.e. except for no outgoing laser at the 1 st bar position, the outgoing laser power at the corresponding positions of the remaining bars is P. The total power P in of the laser incident on the dispersive optical element is expressed asThe reflectance R i =1/i gives: p in = P. Since the diffraction efficiency R diffractive -100% of the dispersive optical element, the diffraction power P diffractive＝Pin =p of the dispersive optical element, the feedback light P diffractive of the dispersive optical element is fed back to the corresponding bars by the partial reflectors R i, and the diffraction power corresponding to the bars is/>, respectivelyThe reflectivity R i of each partial reflector corresponding to each bar is brought to obtain the diffraction return light power of each bar: p ri = P x 10%, i = 1,2,.. N, i.e. the individual bars and the beam shaping system and the partial mirror corresponding to the bars together with the dispersive optical element form an external cavity structure with an external cavity feedback energy ratio of 10% of the output power when the individual bars are free running. The feedback ratio is reasonable and common for constructing an effective semiconductor external cavity laser, at this time, the spectral properties (center wavelength, spectral linewidth, etc.) of the resonant laser in the external cavity are mainly determined by the diffraction center wavelength and bandwidth of the dispersive optical element, while the spectral properties of the outgoing laser power P i at the respective corresponding positions of the 2 nd bar, the 3 rd bar … … th bar are completely determined by the resonant laser in the external cavity.
Preferably, the semiconductor laser array of the present invention is in a continuous or quasi-continuous mode of operation.
Preferably, the emission wavelength of the semiconductor laser array is in the range of 0.4-2.3 um.
Preferably, the light emitting source output face of the semiconductor laser of the present invention (i.e., the light emitting source output face of each bar) may be of conventional reflectivity (R-5%). Or the light-emitting source output surface of the semiconductor laser (namely the light-emitting source output surface of each bar) is plated with an antireflection film (R < 1%).
Preferably, the beam shaping system of the present invention is a combination of a fast axis collimating lens (FAC, fast Axis Collimator) and a slow axis collimating lens (SAC, slow Axis Collimator), and the laser emitted by each bar is collimated and output after being shaped by the fast axis collimating lens and the slow axis collimating lens. Or the beam shaping system is a combination of a beam torsion system (BTS, beam Transformation System) and a cylindrical lens, and the laser emitted by each bar is collimated and output after being subjected to beam shaping by the beam torsion system and the cylindrical lens respectively. Or the beam shaping system is a lens combination which can realize collimation output after beam shaping.
Preferably, a phase correction optical element for correcting the "smiling face effect (SMILE EFFECT)" is also included in the beam shaping system. The high-power semiconductor laser array comprises a plurality of bars, and the bars are not aligned in an ideal straight line due to various factors such as a process and the like during packaging, so that a smiling face effect (SMILE EFFECT) is introduced.
Preferably, the dispersive optical element may be a bulk grating, a surface grating or other optical element having both high diffraction efficiency and narrow band spectral diffraction capability. Further, the deviation between the diffraction center wavelength of the bulk grating and the free running wavelength of the semiconductor is within +/-5 nm, the diffraction efficiency of the bulk grating is as high as possible within the range of 5-99.9%, the diffraction spectrum bandwidth of the bulk grating is selected within the range of 0.03-1 nm (FWHM) according to the requirements, and the grating thickness of the bulk grating is within the range of 0.3-30 mm. Further, the bulk grating needs to be temperature controlled to precisely lock the central wavelength of the whole spectrum output by the semiconductor laser array, the temperature control mode can be heating or refrigerating, and the temperature control element can be resistance or TEC and the like.
Based on the high-power semiconductor laser array wavelength locking and linewidth compressing device, the method for realizing the high-power semiconductor laser array wavelength locking and linewidth compressing is realized, and n beams of laser output by n bars in the semiconductor laser array are respectively collimated by the corresponding beam shaping system, so that parallel output of the laser beams is realized. The parallel laser beams output from each beam shaping system are respectively incident to the corresponding partial reflectors, one part of the laser beams are reflected by the corresponding partial reflectors, then sequentially reflected by other partial reflectors following the emission light path and finally incident to the dispersion optical element, and the other part of the laser beams are transmitted out through the partial reflectors, and the transmitted light is the final output laser of the semiconductor. The diffracted light of the dispersive optical element returns along the original path, and is respectively and again incident into each bar of the semiconductor laser array through the reflection of each partial reflector, and each bar, a beam shaping system corresponding to each bar, a partial reflector and the dispersive optical element form an external cavity structure. The adjustment of the emergent laser power at the corresponding positions of each bar can be realized by designing the reflectivity R i of each partial reflector. The output center wavelength of the semiconductor laser array can be precisely adjusted and locked by controlling the temperature of the dispersion optical element.
The dispersive optical element of the invention is usually a bulk grating, which has a diffraction efficiency close to 100%, and the diffraction center wavelength and spectral width are selected according to practical application requirements. All the bar outgoing lasers are reflected by the partial reflector, spatially overlapped, and are incident to the body grating at the same incident angle, and the diffracted light returns along the original path and is incident to each bar again through the reflection of the partial reflector; at this time, each bar and the body grating form an external cavity structure, and the central wavelength and the spectrum width of the resonant laser in the external cavity are mainly determined by the characteristics of the body grating, so that the output laser of different bars can be ensured to have precisely consistent central wavelength and expected spectrum width. The volume grating has narrow-band spectral feedback characteristics, so that the linewidth of the output spectrum of the external cavity is compressed. The scheme has the advantages of simple structure and low cost, can ensure the strict consistency of the emergent wavelengths of different luminous sources, is easy to realize accurate wavelength locking and ultra-narrow linewidth spectrum output, has good power expansion capability, and provides a new effective path for the realization and application of narrow linewidth high-power semiconductor laser.
Compared with the prior art, the invention has the advantages that:
1. The invention regulates and controls the spectrum characteristics of different bars in the semiconductor array based on a single block grating, decides from the principle that the different bars emit laser with consistent central wavelength and spectrum linewidth, and the wavelength tuning of the laser is controlled by the block grating, thereby avoiding the problems of the central wavelength deviation among bars and the complex temperature control of each block grating which are difficult to avoid by the conventional scheme of respectively configuring one block grating for each bar, and ensuring the semiconductor array to have high-quality integral spectrum output characteristics.
2. The invention has the advantages of compact structure, easy realization and modularization, and can realize compact and effective power expansion by carrying out up-down or left-right space stacking on each narrow-line-width semiconductor array.
3. Compared with the conventional scheme, the invention reduces the number of expensive optical elements of the volume grating in an order of magnitude, has low cost, is economical and reliable, and is convenient for industrialized popularization and large-scale application.
Drawings
Fig. 1 is a schematic structural view of the present invention.
In the figure:
1. a package and heat sink portion of the semiconductor laser array; 2. a bar; 3. a fast axis collimating lens; 4. a slow axis collimating lens; 5. a partial mirror; 6. emitting laser; 7. and a volume grating.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Referring to fig. 1, this embodiment is illustrated by taking a vertically stacked semiconductor laser array including 10 bars as an example, where 1 is a package and heat sink portion of the semiconductor laser array and 2 is a bar, i.e., a laser emitting region. The semiconductor laser array comprises n bars distributed in a one-dimensional array, n=10, which are respectively marked by Bar 1 and Bar 2 … Bar 10 from top to bottom in fig. 1, and the free-running output power of each Bar is recorded as P (generally in the order of 100W).
Each bar emits directly laser light with a large divergence angle of about 60 ° in the Fast axis (Fast axis) direction and about 10 ° in the Slow axis (Slow axis) direction. After the laser directly emitted by each bar passes through the fast axis collimating lens 3 and the slow axis collimating lens 4 to carry out beam shaping, the divergence angles of the fast axis and the slow axis are respectively compressed to be less than 8mrad and 65mrad, and the beam is transmitted in a near-collimation state.
And 5 is a partial reflector, each bar corresponds to one partial reflector, and as shown in fig. 1, the reflectivity of each partial reflector is different according to the corresponding bar in 10 partial reflectors. The reflectivity of each partial mirror is identified by R i (i=1, 2..10), where R 1 is the reflectivity of the partial mirror corresponding to Bar 1, R 2 is the reflectivity of the partial mirror corresponding to Bar 2, and R … …, R 10 is the reflectivity of the partial mirror corresponding to Bar 10. In this example, the allocation is performed with R i =1/i (i=1, 2..10), i.e. R 1＝100％(1/1)、R2＝50％(1/2)、R3＝33％(1/3)、……、R10 =10% (1/10), the specific values being given in fig. 1. The beam transmission case is illustrated by Bar 2, and the rest of the bars are similar: the power of the outgoing laser beam 6 on the right side of the partial mirror corresponding to Bar 2 is composed of two parts, namely, the power p· (1-R 2) of the partial laser beam transmitted by the outgoing laser beam of Bar 2 through the partial mirror corresponding to Bar 2 and the power p·r 2 of the partial laser beam reflected by R 2 from Bar 1, and the sum of these is P 2 =p.
Since the reflectivity R 1 of the 1 st partial mirror is 100%, the 1 st bar has no corresponding outgoing laser light. In addition to no emitted laser light at the 1 st bar position, for the 2 nd bar, the emitted laser power P i at the respective corresponding positions of the 3 rd bar … … n bar isIn the case of the reflectances R i =1/i of the respective partial mirrors, it can be obtained by calculation: p i = P (i = 2,3,..10), i.e. except for Bar 1 which has no outgoing laser, the outgoing laser power at the corresponding positions of the bars is P. Meanwhile, each bar outgoing laser is reflected by a corresponding partial reflector, then sequentially transmitted by other subsequent partial reflectors on a reflection light path, finally enters the body grating 7 by the total power P in, and the expression of the total power P in is/>The reflectance R i =1/i gives: p in = P. Because of the diffraction efficiency R diffractive -100%, the diffraction power P diffractive＝Pin =p of the bulk grating, and the feedback light P diffractive is respectively fed back into the corresponding Bar i (i=2, 3,..10) by the partial reflector R i, and the diffraction back light powers corresponding to the Bar i are respectivelyCarrying R i gives: p ri = P x 10% (i = 1,2,.. 10), i.e. each bar 2 forms with the fast axis collimator lens 3, the slow axis collimator lens 4, the partial mirror 5 (R i) and the bulk grating 7 an external cavity structure with an external cavity feedback energy ratio of 10% of the power of the single bar free running, which feedback ratio is reasonable and common for constructing an efficient semiconductor external cavity laser, where the spectral properties (center wavelength, spectral linewidth etc.) of the external cavity resonant laser are mainly determined by the diffraction center wavelength and bandwidth of the bulk grating 7, while the spectral properties of the output laser P i (i = 2, 3.. 10) are completely determined by the external cavity resonant laser.
From the above description, by reasonably setting the reflectivity R i of the partial reflector 5, it can be satisfied that the corresponding positions of the bars emit at the same power P, and considering that Bar 1 does not emit laser, the total energy utilization efficiency of the system is about 90% compared with the free running condition; the spectral property of the external cavity corresponding to each bar is determined by a unique volume grating, the external cavities have the same and reasonable energy feedback proportion (about 10 percent), the modification value can be changed by adjusting the distribution of R i), the consistency of the external cavity in the aspects of resonance power and spectral property is ensured, and the output center wavelength of the whole semiconductor array can be accurately regulated and locked by controlling the temperature of the volume Bragg grating (the wavelength temperature drift coefficient is usually 0.01 nm/DEG C).
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. The high-power semiconductor laser array wavelength locking and linewidth compressing device is characterized in that: the device comprises a semiconductor laser array, a beam shaping system, a partial reflector and a dispersion optical element, wherein the dispersion optical element is a volume grating or a surface grating with high diffraction efficiency and narrow-band spectrum diffraction capacity;
The semiconductor laser array comprises n bars distributed in a one-dimensional array, namely a 1 st bar and a2 nd bar … th bar in sequence, wherein n is more than or equal to 2; the laser emitted by each bar is respectively and sequentially input into a corresponding beam shaping system and a partial reflector, the partial reflectors corresponding to the 1 st bar and the 2 nd bar … th bar are respectively a 1 st partial reflector and a2 nd partial reflector … … nth partial reflector, the n partial reflectors are distributed in a one-dimensional array, and the emission light paths of the n partial reflectors are on the same straight line; the dispersion optical element is arranged on the reflection light path of the nth part reflector; the n laser beams are respectively collimated by the corresponding beam shaping systems, so that parallel output of the laser beams is realized; the parallel laser beams output from each beam shaping system are respectively incident to the corresponding partial reflectors, one part of the laser beams is reflected by the corresponding partial reflectors and then sequentially reflected by other partial reflectors behind the reflecting light path and finally incident to the dispersion optical element, the other part of the laser beams is transmitted out through the partial reflectors, and the transmitted light is the final output laser of the semiconductor; the diffracted light of the dispersive optical element returns along the original path, and is respectively and again incident into each bar of the semiconductor laser array through the reflection of each partial reflector, and each bar, a beam shaping system corresponding to each bar, a partial reflector and the dispersive optical element form an external cavity structure.
2. The high power semiconductor laser array wavelength locking and linewidth compressing apparatus of claim 1 wherein: the output center wavelength of the semiconductor laser array can be accurately adjusted and locked by controlling the temperature of the dispersion optical element; the adjustment of the emergent laser power at the corresponding positions of each bar can be realized by designing the reflectivity R i of each partial reflector.
3. The high power semiconductor laser array wavelength locking and linewidth compressing apparatus of claim 1 wherein: n bars in the semiconductor laser array are arranged in a vertical stacking or horizontal stacking mode, and the spaces among the bars are equal;
When n bars are vertically stacked, the 1 st bar, the 2 nd bar … … th bar, the n groups of beam shaping systems and the n partial reflectors are all sequentially arranged into a one-dimensional array from top to bottom;
when n bars are horizontally stacked, the 1 st bar, the 2 nd bar … … th bar, the n groups of beam shaping systems and the n partial reflectors are all arranged in sequence from left to right to form a one-dimensional array.
4. The high power semiconductor laser array wavelength locking and linewidth compressing apparatus of claim 1 wherein: the reflectances R i of the partial mirrors are assigned as R i =1/i, i=1, 2..n, i.e., the reflectance R 1 of the 1 st partial mirror is 100%, the reflectance of the 2 nd partial mirror is 50%, … …, and the reflectance of the n th partial mirror is 1/n.
5. The high power semiconductor laser array wavelength locking and linewidth compressing apparatus of claim 1 wherein: the beam shaping system is a combination of a fast axis collimating lens and a slow axis collimating lens, and the laser emitted by each bar is collimated and output after being subjected to beam shaping by the fast axis collimating lens and the slow axis collimating lens respectively;
or the beam shaping system is a combination of a beam torsion system and a cylindrical lens, and the laser emitted by each bar is collimated and output after being subjected to beam shaping by the beam torsion system and the cylindrical lens respectively.
6. The high power semiconductor laser array wavelength locking and linewidth compressing apparatus of claim 5 wherein: the beam shaping system further comprises a phase correcting optical element.
7. The high power semiconductor laser array wavelength locking and linewidth compressing apparatus of claim 2 or 3 or 4 or 5 or 6, wherein: the dispersion optical element is a bulk grating, the deviation between the diffraction center wavelength of the bulk grating and the free running wavelength of the semiconductor laser is within +/-5 nm, the diffraction efficiency of the bulk grating is 5-99.9%, the diffraction spectrum bandwidth of the bulk grating is 0.03-1 nm, and the grating thickness of the bulk grating is 0.3-30 mm; the temperature control mode of the bulk grating is heating or refrigerating, and the temperature control element is a resistor or TEC.
8. A method for realizing wavelength locking and linewidth compression of a high-power semiconductor laser array is characterized by comprising the following steps: a high power semiconductor laser array wavelength locking and linewidth compressing apparatus implementation based on any one of claims 1 to 6.
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| CN112652950B (en) * | 2020-11-26 | 2021-12-14 | 苏州长光华芯光电技术股份有限公司 | Wavelength locking semiconductor laser system |
| CN112993747B (en) * | 2021-02-08 | 2022-05-27 | 苏州长光华芯光电技术股份有限公司 | Wavelength locking semiconductor laser system |
| CN114243452A (en) * | 2022-02-24 | 2022-03-25 | 深圳市星汉激光科技股份有限公司 | Interlocking light path of semiconductor laser |
| CN115799957B (en) * | 2022-10-24 | 2023-08-15 | 中国人民解放军国防科技大学 | Method and system for locking wavelength and narrowing linewidth of high-power semiconductor stacked array laser |
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