CN113725703A - Raman laser oscillator with continuously tunable wavelength - Google Patents

Abstract

Translated fromChinese

本发明公开了一种波长连续可调谐拉曼激光振荡器，泵浦源出射泵浦光，依次经过望远镜器件和光隔离器后进入谐振腔，泵浦光进入KTA晶体并激发非线性效应产生信号光和闲频光，通过对腔镜镀膜的设计使泵浦光和信号光离开谐振腔，使闲频光在腔内不断振荡；闲频光通过聚焦透镜耦合进金刚石晶体中心，在腔内不断振荡并激发SRS产生拉曼光，拉曼光通过输出镜输出。通过对激光谐振腔的镀膜设计，能在激光谐振腔内先后实现OPO与SRS两种非线性效应，在波长1.06μm的泵浦光下获得3.46‑3.48μm波段闲频光，进而获得6.44‑6.48μm波段的可调谐拉曼光输出，且拉曼光光束质量高，光谱线宽窄。

The invention discloses a wavelength continuously tunable Raman laser oscillator. The pump source emits pump light, passes through a telescope device and an optical isolator in sequence, and then enters a resonant cavity. The pump light enters a KTA crystal and excites nonlinear effects to generate signal light By designing the cavity mirror coating, the pump light and the signal light leave the resonant cavity, so that the idler light oscillates continuously in the cavity; the idler light is coupled into the center of the diamond crystal through the focusing lens and oscillates continuously in the cavity And excite the SRS to generate Raman light, which is output through the output mirror. Through the coating design of the laser resonator, two nonlinear effects of OPO and SRS can be realized successively in the laser resonator, and the 3.46-3.48μm band idler light can be obtained under the pump light with a wavelength of 1.06μm, and then the 6.44-6.48 Tunable Raman light output in the μm band, with high beam quality and narrow spectral linewidth.

Description

Raman laser oscillator with continuously tunable wavelength

Technical Field

The invention relates to the field of lasers, in particular to a Raman laser oscillator with continuously tunable wavelength.

Background

The frequency conversion technology of nonlinear optics is an important branch of the optical field and is the most effective technical means for obtaining multi-wavelength and tunable laser. Stimulated Raman Scattering (SRS), a third-order nonlinear effect, is a significant feature of SRS that is self-phase-matched, so that the light-to-light conversion efficiency is largely independent of temperature and angle. The advantage of self-phase matching is to convert incoherent light into output light of high beam quality. The spatial distribution of the gain is the convolution of the pumping field and the Stokes field, so that the space is smoother, and the gain distribution of the Stokes light is gradually close to a Gaussian shape after the Stokes light repeatedly returns in the resonant cavity, thereby obtaining the Stokes light close to the diffraction limit. The Raman laser based on the SRS has the advantages of beam purification, Raman gain without space hole burning effect and the like, and has great potential in the aspect of developing a laser with high output power, narrow line width, near diffraction limit beam quality and compact structure integration by combining with Raman crystals with excellent properties such as diamond crystals and the like.

An Optical Parametric Oscillator (OPO) is a second-order nonlinear effect and is a very valuable nonlinear optical technology, and the OPO technology can expand laser wavelength to medium-wave infrared and long-wave infrared bands by using the frequency conversion function of a nonlinear crystal, convert high-energy short-wave laser into long-wave laser and realize the output of the long-wave laser with a continuously tunable spectrum. For example: the wavelength of the medium wave of 3-5 mu m and the wavelength of the long wave infrared laser of 8-12 mu m are in the atmospheric window wave band, and the method has wide application prospect in the fields of laser medical treatment, laser radar, environmental monitoring, photoelectric countermeasure and the like.

The commonly used Raman crystals in the current Raman laser include optical-grade diamond crystals, nitrate crystals, tungstate crystals, vanadate crystals and the like. Has excellent properties such as diamond crystal with a Raman frequency shift coefficient of 1332.3cm^-1It is mostly used for pumping near infrared band of 1.06 μm to 1.24 μm or 1.49 μm. Compared to the OPO technique, the frequency conversion range of SRS depends on ramanThe frequency shift coefficient of the crystal is small in frequency conversion range, and the wavelength is single and fixed and cannot be tuned.

Disclosure of Invention

The invention provides a Raman laser oscillator with continuously tunable wavelength, which firstly realizes OPO in the same resonant cavity and then utilizes the OPO to generate wavelength to excite SRS, and has the advantages of simple structure, high quality of output Raman light beams and tunable output wavelength, and the following description is provided:

the pump light emitted from the pump source sequentially passes through the telescope device and the optical isolator and then enters the resonant cavity, and the pump light firstly enters the KTA crystal (KTiOAsO)₄Potassium titanyl arsenate) and exciting a nonlinear effect to generate signal light and idler frequency light, and enabling the pump light and the signal light to leave the resonant cavity through the design of a coated film of the cavity mirror so as to enable the idler frequency light to continuously oscillate in the cavity;

the idler frequency light is coupled into the center of the diamond crystal through the focusing lens, continuously oscillates in the cavity and excites the SRS to generate Raman light, and the Raman light is output through the output mirror.

In a first aspect, an apparatus for generating wavelength tunable laser light, the apparatus comprising: a pumping source, a telescope device, an optical isolator, a laser resonant cavity and a long-pass filter,

the laser resonator comprises: the device comprises a first input mirror, a first KTA crystal, a first focusing lens, a first diamond crystal and a first output mirror;

the first input mirror and the first output mirror form a linear cavity structure which is plated with a dielectric film, a pumping source with the wavelength of 1.06 mu m enters the first KTA crystal through the resonant cavity once and interacts with the first KTA crystal to generate signal light and idler frequency light, and the first KTA crystal is subjected to temperature tuning to obtain 1.52-1.54 mu m waveband signal light and 3.46-3.48 mu m waveband idler frequency light;

the 1.52-1.54 μm waveband signal light leaves the resonant cavity after passing through the first focusing lens, the first diamond crystal and the first output mirror; 3.46-3.48 μm waveband idler light is coupled to the center of the first diamond crystal through the first focusing lens and excites SRS to generate 6.44-6.48 μm waveband Raman light; and 6.44-6.48 mu m waveband Raman light is output through the first output mirror and the long-pass filter.

Wherein, the first input mirror is a plano-concave mirror, the two sides are coated with films, the reflectivity of the concave surface to idler light with the wave band of 3.46-3.48 mu m and Raman light with the wave band of 6.44-6.48 mu m is more than 99.9 percent, and the transmissivity of the two sides to pump light with the wave band of 1.06 mu m is more than 99.5 percent;

the first output mirror is a plano-concave mirror, the two surfaces of the first output mirror are coated with films, the reflectivity of the concave surface to 3.46-3.48 mu m waveband idler frequency light is more than 99.9%, the transmissivity of the two surfaces to 1.06 mu m pump light and 1.52-1.54 mu m waveband signal light is more than 99.5%, and the two surfaces are partially transmitted to 6.44-6.48 mu m waveband Raman light;

the two sides of the first focusing lens are coated with films, and the transmissivity of the first focusing lens to pump light with the wavelength of 1.06 mu m, signal light with the wavelength of 1.52-1.54 mu m, idler light with the wavelength of 3.46-3.48 mu m and Raman light with the wavelength of 6.44-6.48 mu m is more than 99.5 percent;

the long-pass filter is used for filtering 1.06 mu m pump light, 1.52-1.54 mu m wave band signal light and 3.46-3.48 mu m wave band idler light, and the transmissivity of the light with wave band of more than 6 mu m is more than 99.5%.

Preferably, the first KTA crystal is cut at a phase matching angle of pump light having a wavelength of 1.06 μm, the cut angle θ being 90 °,

for class II phase matching, crystal size 10X 20mm³(ii) a The tuning mode of the first KTA crystal is temperature tuning, and 1.52-1.54 mu m waveband signal light and 3.46-3.48 mu m waveband idler frequency light can be obtained by adjusting the temperature of the crystal through a temperature control furnace; two ends of the first KTA crystal are coated with films, and the transmissivity of the two ends of the first KTA crystal to pump light with the wavelength of 1.06 mu m, signal light with the wavelength of 1.52-1.54 mu m, idler light with the wavelength of 3.46-3.48 mu m and Raman light with the wavelength of 6.44-6.48 mu m>99.5％。

Further, the first diamond crystal was cut at a brewster angle θ of 67.3 ° and had a crystal size of 5 × 4 × 1.2mm³。

In a second aspect, a device for generating wavelength tunable laser comprises: a pumping source, a telescope device, an optical isolator, a laser resonant cavity and a long-pass filter,

the laser resonator comprises: the second input mirror, the second KTA crystal, the plane mirror, the second focusing lens, the second diamond crystal and the second output mirror; the second input mirror, the plane mirror and the second output mirror form a V-shaped cavity structure and are plated with dielectric films; pumping light with the wavelength of 1.06 mu m enters the second KTA crystal through the second input mirror, interacts with the second KTA crystal to generate signal light and idler frequency light, and performs temperature tuning on the first KTA crystal to obtain 1.52-1.54 mu m waveband signal light and 3.46-3.48 mu m waveband idler frequency light; 1.06 μm pump light and 1.52-1.54 μm wave band signal light leave the resonant cavity through the plane mirror; 3.46-3.48 μm waveband idler light is reflected by the plane mirror, coupled to the center of the second diamond crystal through the second focusing lens and excites SRS to generate 6.44-6.48 μm waveband Raman light; and 6.44-6.48 mu m waveband Raman light is output after passing through the second output mirror and the long-pass filter.

Preferably, the second input mirror is a plano-concave mirror, the two sides of the second input mirror are coated with films, the transmissivity of the two sides to the pump light with the wavelength of 1.06 mu m is more than 99.5%, and the reflectivity of the concave surface to the idler light with the wavelength of 3.46-3.48 mu m and the Raman light with the wavelength of 6.44-6.48 mu m is more than 99.9%;

the second output mirror is a plano-concave mirror, the two sides of the second output mirror are coated with films, the reflectivity of the concave surface to idler frequency light with a wave band of 3.46-3.48 mu m is more than 99.9%, and the two sides of the second output mirror partially transmit to Raman light with a wave band of 6.44-6.48 mu m;

the two sides of the plane mirror are coated with films, the transmissivity of the film to 1.06 mu m pump light and 1.52-1.54 mu m wave band signal light is more than 99.5%, the reflectivity of the film to 3.46-3.48 mu m wave band idler light and 6.44-6.48 mu m wave band Raman light is more than 99.9%, and the plane mirror is used for adjusting the folding angle of the V-shaped cavity;

the two sides of the second focusing lens are coated with films, and the transmissivity of the second focusing lens to idler light in a wave band of 3.46-3.48 mu m and Raman light in a wave band of 6.44-6.48 mu m is more than 99.5 percent;

the long-pass filter is used for filtering 3.46-3.48 mu m waveband idler frequency light, and the transmissivity of the light with the waveband of more than 6 mu m is more than 99.5%.

Further, the second KTA crystal is cut at a phase matching angle of 1.06 μm pump light, a cut angle θ is 90 °,

for class II phase matching, crystal size 10X 20mm³(ii) a The tuning mode of the first KTA crystal is temperature tuning, and under the pump light with the wavelength of 1.06 mu m, 1.52-1.54 mu m wave band signal light and 3.46-3.48 mu m wave band idler frequency light can be obtained by adjusting the temperature of the crystal through a temperature control furnace; two ends of the first KTA crystal are coated with films, and the transmissivity of the first KTA crystal to pump light with the wavelength of 1.06 mu m, signal light with the wavelength of 1.52-1.54 mu m, idler light with the wavelength of 3.46-3.48 mu m and Raman light with the wavelength of 6.44-6.48 mu m>99.5％。

Preferably, the second diamond crystal is cut at 67.3 ° brewster angle θ, and has a crystal size of 5 × 4 × 1.2mm³(ii) a The pump source emits pulsed linearly polarized pump light of wavelength 1.06 μm.

The optical isolator is composed of a first half wave plate, a first polarizer, a Faraday rotator, a second half wave plate and a second polarizer;

the telescope device is used for shaping and collimating the pump light beam and consists of two convex lenses, the light passing surfaces of the convex lenses are coated with dielectric films, and the transmissivity of the telescope device to the pump light with the wavelength of 1.06 mu m is more than 99.5%.

The technical scheme provided by the invention has the beneficial effects that:

1. the invention completes two nonlinear effects of OPO and SRS in the laser resonant cavity in sequence. The combination of two nonlinear frequency conversion technologies greatly increases the wavelength conversion scale, and simultaneously combines the temperature tuning property of OPO, so that 3.46-3.48 mu m waveband idle frequency light can be obtained from pump light with the wavelength of 1.06 mu m, further tunable Raman light output with the waveband of 6.44-6.48 mu m can be obtained, and the Raman light beam has high quality and narrow spectral line width;

2. according to the invention, through the design of an input mirror, an output mirror and two crystal coatings of the laser resonant cavity, two nonlinear effects of OPO and SRS can be realized only by using two cavity mirrors, and the resonant cavity is an OPO cavity, a Raman cavity and has two structures of a line cavity and a V-shaped cavity; the design not only simplifies the structure of the resonant cavity and reduces the loss caused by the cavity mirror, but also hopes to obtain a novel laser with compact structure and convenient adjustment.

Drawings

FIG. 1 is a schematic diagram of a Raman laser oscillator with continuously tunable wavelength;

FIG. 2 is a schematic diagram of an optical isolator;

FIG. 3 is a schematic diagram of a linear laser resonator structure;

FIG. 4 is a schematic diagram of a V-shaped laser resonator structure.

In the drawings, the components represented by the respective reference numerals are listed below:

1: a pump source; 2: a telescope device;

3: an optical isolator; 4: a laser resonant cavity;

5: a long-pass filter;

wherein

3-1: a first quarter wave plate; 3-2: a first polarizer;

3-3: a Faraday rotator; 3-4: a second half wave plate;

3-5: a second polarizer;

4-1: a first input mirror; 4-2: a first KTA crystal;

4-3: a first focusing lens; 4-4: a first diamond crystal;

4-5: a first output mirror; 4-6: a second input mirror;

4-7: a second KTA crystal; 4-8: a plane mirror;

4-9: a second focusing lens; 4-10: a second diamond crystal;

4-11: a second output mirror.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention are described in further detail below.

The embodiment of the invention provides a generation device of wavelength tunable laser, which combines two nonlinear effects of OPO and SRS to obtain wavelength tunable Raman optical output. Both OPO and SRS are commonly used nonlinear frequency conversion techniques, and the principle of OPO is that pump light is incident into an OPO crystal to cause noise photons, so that coherent outputs of signal light and idler light are obtained, and tunable wavelength outputs can be obtained through a temperature tuning means. SRS is a process in which incident intense light photons interact with atoms inside the crystal to produce Stokes photons with a certain frequency shift, the amount of which depends on the inherent frequency shift coefficient of the raman crystal. According to the embodiment of the invention, through the design of the coating film of the cavity mirror, the resonant cavity is not only an OPO cavity but also a Raman cavity, the OPO and the SRS can be realized in the resonant cavity, idle frequency light with a wave band of 3.46-3.48 mu m can be obtained under pumping light with a wavelength of 1.06 mu m, tunable Raman light output with a wave band of 6.44-6.48 mu m can be further obtained, and the Raman light has high beam quality and narrow spectral line width.

Example 1

Referring to fig. 1 and 3, a wavelength tunable laser generating apparatus includes: the device comprises a pumping source 1, a telescope device 2, anoptical isolator 3, a laserresonant cavity 4 and a long-pass filter 5.

Wherein, the pumping source 1 emits pulse linear polarization pumping light with the wavelength of 1.06 μm, and the pumping light sequentially passes through the telescope device 2 and the optical isolator 3 and then enters the laser resonant cavity 4; the laser resonator 4 includes: the device comprises a first input mirror 4-1, a first KTA crystal 4-2, a first focusing lens 4-3, a first diamond crystal 4-4 and a first output mirror 4-5; the first input mirror 4-1 and the first output mirror 4-5 form a linear cavity structure and are both plated with dielectric films; pumping light with the wavelength of 1.06 mu m is incident into a first KTA crystal 4-2 after passing through a first input mirror 4-1 to excite OPO, and temperature tuning is carried out on the first KTA crystal 4-2 to obtain signal light with the wavelength of 1.52-1.54 mu m and idler frequency light with the wavelength of 3.46-3.48 mu m; the generated 1.52-1.54 mu m wave band signal light leaves the laser resonant cavity after passing through the first focusing lens 4-3, the first diamond crystal 4-4 and the first output mirror 4-5, and the 3.46-3.48 mu m wave band idler frequency light is coupled to the center of the first diamond crystal 4-4 through the first focusing lens 4-3 and oscillates in the resonant cavity to excite the SRS to generate 6.44-6.48 mu m wave band Raman light; raman light with the wave band of 6.44-6.48 mu m is output after passing through a first output mirror 4-5 and a long-pass filter 5.

The first input mirror 4-1 is a planoconcave mirror, two surfaces of the planoconcave mirror are coated with films, the transmissivity of the two surfaces to pump light with the wavelength of 1.06 mu m is more than 99.5 percent, and the reflectivity of the concave surface to idler light with the wavelength of 3.46-3.48 mu m and Raman light with the wavelength of 6.44-6.48 mu m is more than 99.9 percent; the first output mirror 4-5 is a planoconcave mirror, the two sides of which are coated with films, the reflectivity of the concave surface to 3.46-3.48 mu m waveband idler frequency light is more than 99.9%, the transmissivity of the two sides to 1.06 mu m pump light and 1.52-1.54 mu m waveband signal light is more than 99.5%, and the transmissivity can be determined according to specific conditions so as to obtain the optimal output power for the Raman light part of 6.44-6.48 mu m waveband.

The first KTA crystal 4-2 is cut at a phase matching angle of 1.06 μm pump light, the cut angle θ is 90 °,

for class II phase matching, crystal size 10X 20mm³(ii) a The tuning mode of the first KTA crystal 4-2 is temperature tuning, and 1.52-1.54 mu m wave band signal light and 3.46-3.48 mu m wave band idler frequency light can be obtained by adjusting the temperature of the crystal through a temperature control furnace; the two ends of the first KTA crystal 4-2 are coated with films, and the transmissivity of the first KTA crystal to pump light with the wavelength of 1.06 mu m, signal light with the wavelength of 1.52-1.54 mu m, idler light with the wavelength of 3.46-3.48 mu m and Raman light with the wavelength of 6.44-6.48 mu m>99.5％。

The first diamond crystal 4-4 was cut at 67.3 ° brewster angle α, and had a crystal size of 5 × 4 × 1.2mm³And both ends of the film can be not coated.

The telescope device 2 is composed of two convex lenses, the two sides of the convex lenses are coated with films, the transmissivity of pump light with the wavelength of 1.06 mu m is more than 99.5%, the beam aperture adjustment and collimation of the telescope device 2 are well known by the technical personnel in the field, and the embodiment of the invention is not described in detail.

Referring to fig. 2, theoptical isolator 3 is composed of a first one-half wave plate 3-1, a first polarizer 3-2, a faraday rotator 3-3, a second one-half wave plate 3-4, and a second polarizer 3-5, and is used for unidirectional propagation of pump light having a wavelength of 1.06 μm, preventing return light from damaging the pump source 1.

The two sides of the first focusing lens 4-3 are coated with films, and the transmissivity of the first focusing lens to pump light with the wavelength of 1.06 mu m, signal light with the wavelength of 1.52-1.54 mu m, idler frequency light with the wavelength of 3.46-3.48 mu m and Raman light with the wavelength of 6.44-6.48 mu m is more than 99.5 percent; the long-pass filter 5 is used for filtering 1.06 mu m pump light, 1.52-1.54 mu m wave band signal light and 3.46-3.48 mu m wave band idler light, and the transmissivity of the light with wave band of more than 6 mu m is more than 99.5%.

Example 2

Referring to fig. 1 and 4, a wavelength tunable laser generating apparatus includes: the device comprises a pumping source 1, a telescope device 2, anoptical isolator 3, a laserresonant cavity 4 and a long-pass filter 5.

Wherein, the pumping source 1 emits pulse linear polarization pumping light with the wavelength of 1.06 μm, and the pumping light sequentially passes through the telescope device 2 and the optical isolator 3 and then enters the laser resonant cavity 4; the laser resonator 4 includes: a second input mirror 4-6, a second KTA crystal 4-7, a plane mirror 4-8, a second focusing lens 4-9, a second diamond crystal 4-10 and a second output mirror 4-11; the second input mirror 4-6, the plane mirror 4-8 and the second output mirror 4-11 form a V-shaped cavity structure; the 1.06 mu m pump light is incident into a second KTA crystal 4-7 after passing through a second input mirror 4-6 to excite OPO, and the temperature tuning is carried out on the second KTA crystal 4-7 to obtain 1.52-1.54 mu m waveband signal light and 3.46-3.48 mu m waveband idler frequency light; 1.06 mu m pump light and 1.52-1.54 mu m wave band signal light leave the resonant cavity through a plane mirror 4-8, 3.46-3.48 mu m wave band idler frequency light is reflected through the plane mirror 4-8, is coupled to the center of a second diamond crystal 4-10 through a second focusing lens 4-9, and oscillates in the resonant cavity to excite 6.44-6.48 mu m wave band Raman light generated by SRS; raman light with the wave band of 6.44-6.48 mu m is output after passing through a second output mirror 4-11 and a long-pass filter 5.

The second input mirror 4-6 is a plano-concave mirror, two surfaces of the plano-concave mirror are coated with films, the transmissivity of the two surfaces to the pump light with the wavelength of 1.06 mu m is more than 99.5%, and the reflectivity of the concave surface to the idler frequency light with the wavelength of 3.46-3.48 mu m and the Raman light with the wavelength of 6.44-6.48 mu m is more than 99.9%; the second output mirror 4-11 is a plano-concave mirror, the two sides of the plano-concave mirror are coated with films, the reflectivity of the concave surface to the idler frequency light with the wave band of 3.46-3.48 mu m is more than 99.9%, the two sides of the plano-concave mirror partially transmit to the Raman light with the wave band of 6.44-6.48 mu m, and the transmissivity can be determined according to specific conditions so as to obtain the optimal output power; the two sides of the plane mirror 4-8 are coated with films, the transmissivity of the film to 1.06 mu m pump light and 1.52-1.54 mu m wave band signal light is more than 99.5%, the reflectivity of the film to 3.46-3.48 mu m wave band idler light and 6.44-6.48 mu m wave band Raman light is more than 99.9%, and the plane mirror 4-8 is used for adjusting the folding angle of the V-shaped cavity so as to obtain the optimal output power.

The second KTA crystal 4-7 is cut at a phase matching angle of 1.06 μm pump light, the cut angle θ is 90 °,

for class II phase matching, crystal size 10X 20mm³(ii) a The tuning mode of the second KTA crystal 4-7 is temperature tuning, and the signal light with the wavelength of 1.52-1.54 mu m and the idler frequency light with the wavelength of 3.46-3.48 mu m can be obtained by adjusting the temperature of the crystal through a temperature control furnace; the two ends of the second KTA crystal 4-7 are coated with films, and the transmissivity of the second KTA crystal to pump light with the wavelength of 1.06 mu m, signal light with the wavelength of 1.52-1.54 mu m, idler light with the wavelength of 3.46-3.48 mu m and Raman light with the wavelength of 6.44-6.48 mu m>99.5％。

A second diamond crystal 4-10 was cut at 67.3 deg. brewster angle α with a crystal size of 5 × 4 × 1.2mm³And both ends of the crystal can be not coated with films.

The telescope device 2 is composed of two convex lenses, the two sides of the convex lenses are coated with films, the transmissivity of pump light with the wavelength of 1.06 mu m is more than 99.5%, the beam aperture adjustment and collimation of the telescope device 2 are well known by the technical personnel in the field, and the embodiment of the invention is not described in detail.

Referring to fig. 2, theoptical isolator 3 is composed of a first one-half wave plate 3-1, a first polarizer 3-2, a faraday rotator 3-3, a second one-half wave plate 3-4, and a second polarizer 3-5, and is used for unidirectional propagation of pump light having a wavelength of 1.06 μm, preventing return light from damaging the pump source 1.

The two sides of the second focusing lens 4-9 are coated with films, and the transmissivity of the second focusing lens to idler frequency light in a wave band of 3.46-3.48 mu m and Raman light in a wave band of 6.44-6.48 mu m is more than 99.5 percent; the long-pass filter 5 is used for filtering 3.46-3.48 mu m waveband idler frequency light, and the transmissivity of the light with the waveband of 6 mu m is greater than 99.5%.

The embodiment of the invention does not limit the types of other devices except the types of the devices which are specially explained,

any device capable of performing the above functions may be used.

Those skilled in the art will appreciate that the drawings are only schematic illustrations of preferred embodiments, and the above-described embodiments of the present invention are merely provided for description and do not represent the merits of the embodiments.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (9)

Translated fromChinese

1.一种波长连续可调谐拉曼激光振荡器，其特征在于，所述装置包括：泵浦源、望远镜器件、光隔离器、激光谐振腔、长通滤光片,1. a wavelength continuously tunable Raman laser oscillator, is characterized in that, described device comprises: pump source, telescope device, optical isolator, laser resonator, long-pass filter,所述激光谐振腔包括：第一输入镜、第一KTA晶体、第一聚焦透镜、第一金刚石晶体、第一输出镜；The laser resonator includes: a first input mirror, a first KTA crystal, a first focusing lens, a first diamond crystal, and a first output mirror;所述第一输入镜和第一输出镜构成线形腔结构均镀有介质膜，波长1.06μm的泵浦源单次通过谐振腔，进入所述第一KTA晶体，与所述第一KTA晶体相互作用产生信号光和闲频光，所述第一KTA晶体进行温度调谐获得1.52-1.54μm波段信号光和3.46-3.48μm波段闲频光；The first input mirror and the first output mirror form a linear cavity structure, both of which are coated with a dielectric film, and the pump source with a wavelength of 1.06 μm passes through the resonator once, enters the first KTA crystal, and interacts with the first KTA crystal. The action generates signal light and idler light, and the first KTA crystal performs temperature tuning to obtain signal light in the 1.52-1.54 μm band and idler light in the 3.46-3.48 μm band;所述1.52-1.54μm波段信号光经所述第一聚焦透镜、所述第一金刚石晶体和所述第一输出镜后离开谐振腔；3.46-3.48μm波段闲频光经所述第一聚焦透镜耦合到所述第一金刚石晶体中心并激发SRS，产生6.44-6.48μm波段拉曼光；6.44-6.48μm波段拉曼光经过所述第一输出镜和所述长通滤光片输出。The 1.52-1.54μm band signal light leaves the resonant cavity after passing through the first focusing lens, the first diamond crystal and the first output mirror; the 3.46-3.48μm band idler light passes through the first focusing lens It is coupled to the center of the first diamond crystal and excites the SRS to generate Raman light in the 6.44-6.48 μm band; the Raman light in the 6.44-6.48 μm band is output through the first output mirror and the long-pass filter.2.根据权利要求1所述的一种一种波长连续可调谐拉曼激光振荡器，其特征在于，2. a kind of wavelength continuously tunable Raman laser oscillator according to claim 1, is characterized in that,所述第一输入镜为平凹镜，两面镀膜，凹面对3.46-3.48μm波段闲频光和6.44-6.48μm波段拉曼光的反射率>99.9％，两面对1.06μm泵浦光的透射率>99.5％；The first input mirror is a plano-concave mirror, coated on both sides, the reflectivity of the concave surface to the idler light in the 3.46-3.48 μm band and the Raman light in the 6.44-6.48 μm band is >99.9%, and the two sides are opposite to the 1.06 μm pump light. Transmittance>99.5%;所述第一输出镜为平凹镜，两面镀膜，凹面对3.46-3.48μm波段闲频光的反射率>99.9％，两面对1.06μm泵浦光和1.52-1.54μm波段信号光透射率>99.5％，两面对6.44-6.48μm波段拉曼光部分透射；The first output mirror is a plano-concave mirror, coated on both sides, the reflectivity of the concave face to the idler light in the 3.46-3.48μm band is >99.9%, and the two faces of the 1.06μm pump light and the 1.52-1.54μm band signal light transmittance >99.5%, both sides partially transmit Raman light in the 6.44-6.48μm band;所述第一聚焦透镜两面镀膜，对1.06μm泵浦光、1.52-1.54μm波段信号光、3.46-3.48μm波段闲频光和6.44-6.48μm波段拉曼光的透射率>99.5％；The first focusing lens is coated on both sides, and the transmittance to 1.06μm pump light, 1.52-1.54μm band signal light, 3.46-3.48μm band idler light and 6.44-6.48μm band Raman light is >99.5%;所述长通滤光片用于过滤1.06μm泵浦光、1.52-1.54μm波段信号光和3.46-3.48μm波段闲频光，对>6μm波段光的透射率>99.5％。The long-pass filter is used for filtering 1.06 μm pump light, 1.52-1.54 μm band signal light and 3.46-3.48 μm band idler light, and the transmittance to >6 μm band light is >99.5%.3.根据权利要求1所述的一种波长连续可调谐拉曼激光振荡器，其特征在于，3. a kind of wavelength continuously tunable Raman laser oscillator according to claim 1, is characterized in that,所述第一KTA晶体以波长1.06μm泵浦光的相位匹配角度切割，切割角θ＝90°，φ＝0°，为II类相位匹配，晶体尺寸10×10×20mm³；所述第一KTA晶体的调谐方式为温度调谐，通过温控炉调整晶体温度可获得1.52-1.54μm波段信号光和3.46-3.48μm波段闲频光；所述第一KTA晶体两端镀膜，其两端对1.06μm泵浦光、1.52-1.54μm波段信号光、3.46-3.48μm波段闲频光和6.44-6.48μm波段拉曼光的透射率>99.5％。The first KTA crystal is cut at a phase matching angle of the pump light with a wavelength of 1.06 μm, the cutting angle is θ=90°, φ=0°, which is type II phase matching, and the crystal size is 10×10×20mm³ ; the first KTA crystal is The tuning method of the KTA crystal is temperature tuning, and the temperature of the crystal is adjusted by a temperature-controlled furnace to obtain signal light in the 1.52-1.54 μm band and idler light in the 3.46-3.48 μm band; The transmittance of μm pump light, 1.52-1.54 μm band signal light, 3.46-3.48 μm band idler light and 6.44-6.48 μm band Raman light is >99.5%.4.根据权利要求1所述的一种波长连续可调谐拉曼激光振荡器，其特征在于，所述第一金刚石晶体以布儒斯特角θ＝67.3°切割，晶体尺寸为5×4×1.2mm³。4. The wavelength continuously tunable Raman laser oscillator according to claim 1, wherein the first diamond crystal is cut at a Brewster angle θ=67.3°, and the crystal size is 5×4× 1.2mm³ .5.一种波长连续可调谐拉曼激光振荡器，其特征在于，包括：泵浦源、望远镜器件、光隔离器、激光谐振腔和长通滤光片，5. A wavelength continuously tunable Raman laser oscillator, characterized in that, comprising: a pump source, a telescope device, an optical isolator, a laser resonator and a long-pass filter,所述激光谐振腔包括：第二输入镜、第二KTA晶体、平面镜、第二聚焦透镜、第二金刚石晶体、第二输出镜；所述第二输入镜、所述平面镜和所述第二输出镜构成V型腔结构，且镀有介质膜；波长1.06μm泵浦光经所述第二输入镜进入所述第二KTA晶体，与所述第二KTA晶体相互作用产生信号光和闲频光，对所述第一KTA晶体进行温度调谐获得1.52-1.54μm波段信号光和3.46-3.48μm波段闲频光；1.06μm泵浦光和1.52-1.54μm波段信号光经所述平面镜离开谐振腔；3.46-3.48μm波段闲频光经所述平面镜反射后，经所述第二聚焦透镜耦合到所述第二金刚石晶体中心并激发SRS，产生6.44-6.48μm波段拉曼光；6.44-6.48μm波段拉曼光经所述第二输出镜和所述长通滤光片后输出。The laser resonator includes: a second input mirror, a second KTA crystal, a plane mirror, a second focusing lens, a second diamond crystal, and a second output mirror; the second input mirror, the plane mirror and the second output mirror The mirror forms a V-shaped cavity structure and is coated with a dielectric film; the pump light with a wavelength of 1.06 μm enters the second KTA crystal through the second input mirror, and interacts with the second KTA crystal to generate signal light and idler light. , the temperature of the first KTA crystal is tuned to obtain the signal light in the 1.52-1.54 μm band and the idler light in the 3.46-3.48 μm band; the 1.06 μm pump light and the 1.52-1.54 μm band signal light leave the resonant cavity through the plane mirror; After the idler light in the 3.46-3.48μm band is reflected by the plane mirror, it is coupled to the center of the second diamond crystal through the second focusing lens and excites the SRS to generate Raman light in the 6.44-6.48μm band; 6.44-6.48μm band Raman light is output after passing through the second output mirror and the long-pass filter.6.根据权利要求5所述的一种波长连续可调谐拉曼激光振荡器，其特征在于，6. A wavelength continuously tunable Raman laser oscillator according to claim 5, characterized in that,所述第二输入镜为平凹镜，两面镀膜，两面对1.06μm泵浦光的透射率>99.5％，凹面对3.46-3.48μm波段闲频光和6.44-6.48μm波段拉曼光的反射率>99.9％；The second input mirror is a plano-concave mirror, coated on both sides, the transmittance of the 1.06 μm pump light on both sides is more than 99.5%, and the concave side is the 3.46-3.48 μm band idler light and the 6.44-6.48 μm band Raman light. Reflectivity>99.9%;所述第二输出镜为平凹镜，两面镀膜，凹面对3.46-3.48μm波段闲频光的反射率>99.9％，两面对6.44-6.48μm波段拉曼光部分透射；The second output mirror is a plano-concave mirror, coated on both sides, the reflectivity of the idler light in the 3.46-3.48μm waveband on the concave face is >99.9%, and the two sides partially transmit the Raman light in the 6.44-6.48μm waveband;所述平面镜两面镀膜，对1.06μm泵浦光和1.52-1.54μm波段信号光透射率>99.5％，对3.46-3.48μm波段闲频光和6.44-6.48μm波段拉曼光的反射率＞99.9％，所述平面镜用于调整V型腔的折叠角度；The flat mirror is coated on both sides, the transmittance to 1.06μm pump light and 1.52-1.54μm band signal light is >99.5%, and the reflectivity to 3.46-3.48μm band idler light and 6.44-6.48μm band Raman light >99.9% , the plane mirror is used to adjust the folding angle of the V-shaped cavity;所述第二聚焦透镜两面镀膜，对3.46-3.48μm波段闲频光和6.44-6.48μm波段拉曼光的透射率>99.5％；The second focusing lens is coated on both sides, and the transmittance of the idler light in the 3.46-3.48 μm band and the Raman light in the 6.44-6.48 μm band is >99.5%;所述长通滤光片用于过滤3.46-3.48μm波段闲频光，对>6μm波段光的透射率>99.5％。The long-pass filter is used for filtering idler light in the 3.46-3.48 μm band, and the transmittance to light in the >6 μm band is >99.5%.7.根据权利要求5所述的一种波长连续可调谐拉曼激光振荡器，其特征在于，7. A wavelength continuously tunable Raman laser oscillator according to claim 5, characterized in that,所述第二KTA晶体以1.06μm泵浦光的相位匹配角度切割，切割角θ＝90°，φ＝0°，为II类相位匹配，晶体尺寸10×10×20mm³；所述第一KTA晶体的调谐方式为温度调谐，在波长1.06μm泵浦光下，通过温控炉调整晶体温度可获得1.52-1.54μm波段信号光和3.46-3.48μm波段闲频光；所述第一KTA晶体两端镀膜，对1.06μm泵浦光、1.52-1.54μm波段信号光、3.46-3.48μm波段闲频光和6.44-6.48μm波段拉曼光的透射率>99.5％。The second KTA crystal is cut at a phase matching angle of 1.06μm pump light, the cutting angle θ=90°, φ=0°, which is type II phase matching, and the crystal size is 10×10×20mm³ ; the first KTA The tuning method of the crystal is temperature tuning. Under the pump light with a wavelength of 1.06 μm, the temperature of the crystal can be adjusted by a temperature-controlled furnace to obtain signal light in the 1.52-1.54 μm band and idler light in the 3.46-3.48 μm band; the first KTA crystal has two wavelengths. End coating, transmittance >99.5% for 1.06μm pump light, 1.52-1.54μm band signal light, 3.46-3.48μm band idler light and 6.44-6.48μm band Raman light.8.根据权利要求5所述的一种波长连续可调谐拉曼激光振荡器，其特征在于，所述第二金刚石晶体以布儒斯特角θ＝67.3°切割，晶体尺寸为5×4×1.2mm³；所述泵浦源发出波长1.06μm的脉冲线偏振泵浦光。8 . The wavelength continuously tunable Raman laser oscillator according to claim 5 , wherein the second diamond crystal is cut at a Brewster angle θ=67.3°, and the crystal size is 5×4× 1.2 mm³ ; the pump source emits pulsed linearly polarized pump light with a wavelength of 1.06 μm.9.根据权利要求1或5所述的一种波长连续可调谐拉曼激光振荡器，其特征在于，9. A wavelength continuously tunable Raman laser oscillator according to claim 1 or 5, characterized in that,所述光隔离器由第一二分之一波片、第一偏振器、法拉第旋光器、第二二分之一波片和第二偏振器组成；The optical isolator is composed of a first half-wave plate, a first polarizer, a Faraday rotator, a second half-wave plate and a second polarizer;所述望远镜器件用于对泵浦光束的整形和准直，所述望远镜器件由两个凸透镜组成，凸透镜的通光面均镀有介质膜，对波长1.06μm泵浦光的透射率>99.5％。The telescope device is used for shaping and collimating the pump beam, the telescope device is composed of two convex lenses, the light-transmitting surfaces of the convex lenses are all coated with a dielectric film, and the transmittance to the pump light with a wavelength of 1.06 μm is >99.5% .

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