Pumping-oscillation integrated narrow-linewidth Ti sapphire laser

Abstract

According to the pumping-oscillation integrated narrow-linewidth Ti sapphire laser of the novel structure, through the integrated design of the Q-switched green light resonant cavity and the Ti sapphire resonant cavity, narrow-linewidth Ti sapphire laser output of the compact structure is achieved; a lens is additionally arranged in the Q-switched green light resonant cavity, and transverse mode distribution of pump light is changed in combination with a cavity type design mode, so that green light pump light spots are matched with the mode of the titanium sapphire resonant cavity; a polarization control device is arranged in the Q-switched green light resonant cavity, so that the problem of polarization pumping matching after pumping-oscillation integration is solved; a pumping-oscillation system is highly coupled by adopting a multicolor mirror double-cavity sharing mode, so that the pumping space of a titanium sapphire system is reduced, and the integration level of the system is improved; the narrow linewidth Ti sapphire laser with the structure has the advantages of simple structure, stable operation and high integration level.

Description

Technical Field

[0001] The invention relates to the technical field of lasers, and in particular to a pump-oscillation integrated narrow-linewidth titanium sapphire laser. Background Art

[0002] With the continuous development of optical measurement technology, different types of narrow linewidth lasers are becoming increasingly important in the fields of precision measurement, combustion diagnosis, quantum information and high-resolution imaging. Among them, titanium sapphire is widely used in laser manufacturing due to its extremely wide fluorescence spectrum (650-1100nm) and good physical properties. The pumping methods of titanium sapphire lasers are mainly semiconductor laser pumping and Q-switched green light pumping. Among them, semiconductor laser pumping is limited by semiconductor manufacturing process and materials, and the output power is limited. It is continuous light pumping and cannot meet the pulse working requirements. The traditional green light Q-switched laser uses Nd-doped gain medium, and the pulse output is achieved by Q-switched crystal, and then the titanium sapphire crystal is pumped by beam shaping. For example, the Chinese utility model patent with application number 201821374948.3 discloses a sub-nanosecond green laser, which pumps the laser crystal by setting a focusing coupling system between the laser resonator and the pump source to adjust the focusing size of the pump source in the laser resonator.

[0003] The current mainstream commercial Ti:sapphire lasers, such as Astrella from Coherent and Phidia from Uptek, are separated from the pump green light, and the size of the entire Ti:sapphire laser is about 1.4*0.9 meters. The Ti:sapphire laser system with this structure is complex, low in integration, poor in system stability, and large in size, making it difficult to meet the needs of laser miniaturization and engineering applications. Summary of the invention

[0004] The purpose of the present invention is to provide a pump-oscillation integrated narrow-linewidth Ti:sapphire laser to solve the technical problems of complex Q-switched green light pumped Ti:sapphire laser system, low integration and poor system stability.

[0005] The technical solution of the present invention to achieve the above-mentioned purpose is:

[0006] A pump-oscillation integrated narrow linewidth titanium sapphire laser, comprising:

[0007] Infrared Q-switching unit, used to generate infrared laser;

[0008] Frequency doubling crystal, used to double the frequency of infrared laser to obtain green laser;

[0009] A first plano-concave reflecting mirror, used for reflecting green laser light;

[0010] The first polychromatic mirror is located between the infrared Q-switching unit and the frequency doubling crystal; it is used to reflect the infrared laser to the frequency doubling crystal; it is used to transmit the green laser reflected by the first plano-concave reflector to the titanium sapphire crystal;

[0011] The frequency doubling crystal is located between the first polychromatic mirror and the first plano-concave reflecting mirror;

[0012] The lens is located between the infrared Q-switching unit and the optical path of the first polychromatic mirror; it is used to adjust the waist position of the green laser beam;

[0013] Ti:sapphire crystal, used to generate initial laser light under the pumping action of green laser light;

[0014] The dispersion element is used to narrow the initial laser line width to obtain the target laser.

[0015] It is further defined that the infrared Q-switching unit comprises a first plane reflector, an infrared laser generating crystal, a polarizer and a Q-switching crystal which are arranged in sequence, and the lens is located between the Q-switching crystal and the first polychromatic mirror.

[0016] It is further defined that the pump-oscillation integrated narrow linewidth titanium sapphire laser also includes a polarization control device for adjusting the polarization direction of the green laser reflected by the first plano-concave reflector; the polarization control device is located between the first polychromatic mirror and the titanium sapphire crystal.

[0017] It is further defined that the pump-oscillation integrated narrow linewidth Ti: sapphire laser also includes an output mirror, the output mirror is used to emit the target laser, and the first polychromatic mirror is located between the output mirror and the polarization control device.

[0018] It is further defined that the dispersion element includes a first dispersion prism, a second dispersion prism and a third dispersion prism arranged in sequence;

[0019] The titanium sapphire crystal, the first dispersion prism, the second dispersion prism and the third dispersion prism are all arranged at a Briggs angle, and the output mirror is a second end face reflection mirror.

[0020] It is further defined that the dispersion element is an output mirror, the output mirror is a transmission volume Bragg grating, the pump-oscillation integrated narrow linewidth titanium sapphire laser also includes a fourth plano-concave reflector, the titanium sapphire crystal is located between the fourth plano-concave reflector and the polarization control device, the first polychromatic mirror is located between the output mirror and the polarization control device, and the titanium sapphire crystal is arranged at a Briggs angle.

[0021] It is further defined that the dispersion element includes a diffraction grating and a fourth dispersion prism, and the pump-oscillation integrated narrow linewidth titanium sapphire laser also includes a third plane reflector and a third end reflector; the first polychromatic mirror is located between the third end reflector and the polarization control device, and the titanium sapphire crystal, the diffraction grating, the fourth dispersion prism and the third plane reflector are arranged in sequence;

[0022] The diffraction grating is used to reflect the initial laser to the fourth dispersion prism, and the fourth dispersion prism is arranged at a Breitbart angle. By adjusting the angle between the third plane reflector and the fourth dispersion prism, the target laser to be reflected is determined; the diffraction grating is also used to output the target laser reflected by the third plane reflector.

[0023] It is further defined that the dispersion element further includes a fourth plane reflector, the fourth plane reflector and the third plane reflector are located on the same side of the fourth dispersion prism, and the fourth plane reflector and the third plane reflector are arranged at intervals around the fourth dispersion prism.

[0024] It is further defined that the pump-oscillation integrated narrow linewidth Ti:sapphire laser further includes a third plano-concave reflector and a second polychromatic mirror, wherein the second polychromatic mirror is disposed between the Ti:sapphire crystal and the diffraction grating;

[0025] The second polychromatic mirror is used to transmit the initial laser light and also to reflect the green laser light to the third plano-concave reflecting mirror.

[0026] Beneficial effects of the present invention:

[0027] 1. The present invention designs an infrared Q-switching unit, a frequency doubling unit, an optical path between a lens and a titanium sapphire crystal and a Q-switched green light resonant cavity, and uses a lens to adjust the position of the green laser beam waist, so that the emitted green laser can be directly pumped onto the titanium sapphire crystal with a spot of appropriate size, and the output of the target laser is achieved in combination with a dispersion element; the traditional spot shaping structure is omitted, so that the overall structure has a higher degree of integration, a smaller volume and a simpler structure, ensuring stable and reliable operation and meeting actual use requirements.

[0028] 2. The present invention provides dispersion elements including a first dispersion prism, a second dispersion prism, a third dispersion prism, a diffraction grating, a fourth dispersion prism and a transmission volume Bragg grating, so that the emitted target laser is a narrow-linewidth laser, thereby meeting the demand for monochromatic narrow-linewidth laser in ozone detection applications.

[0029] 3. The dispersion element of the present invention can realize the output of two-color lasers with narrow line width in similar bands by setting a diffraction grating, a third plane reflector and a fourth plane reflector, thereby meeting the demand for two-color lasers with similar wavelengths in turbulent flame temperature measurement in combustion diagnosis; at the same time, by adding a third plano-concave reflector and a second polychromatic mirror, the pump laser that is not absorbed by the titanium sapphire crystal can be reflected to the titanium sapphire crystal, thereby improving the utilization efficiency of the pump laser. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A top view of the pump-oscillation integrated narrow-linewidth Ti:Sapphire laser according to Embodiment 1 of the present invention;

[0031] Figure 2 This is a light spot distribution diagram of the green Q-switched laser in Example 1 of the present invention;

[0032] Figure 3 This is a schematic diagram of the structure of a dispersion element according to Embodiment 1 of the present invention;

[0033] Figure 4 This is the spot distribution diagram of the narrow linewidth Ti:Sapphire laser in Example 1 of the present invention;

[0034] Figure 5 A top view of the pump-oscillation integrated narrow-linewidth Ti:Sapphire laser according to Embodiment 2 of the present invention;

[0035] Figure 6 A top view of the pump-oscillation integrated narrow-linewidth Ti:sapphire laser according to Embodiment 3 of the present invention;

[0036] In the figure: 100-green Q-switched laser; 101-first plane mirror; 102-infrared laser generating crystal; 103-polarizer; 104-Q-switched crystal; 105-lens; 106-first plano-concave mirror; 107-frequency doubling crystal; 200-narrow linewidth titanium sapphire laser; 201-first polychromatic mirror; 202-titanium sapphire crystal; 203-first dispersion prism; 204-second dispersion prism; 205-third dispersion prism; 206-second plano-concave mirror; 207-output mirror; 208-polarization control device; 209-third end mirror; 300-titanium sapphire two-color laser; 301-third plano-concave mirror; 302-second polychromatic mirror; 303-diffraction grating; 304-fourth dispersion prism; 305-third plane mirror; 306-fourth plane mirror; 400-fourth plano-concave mirror. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Example 1

[0039] refer to Figure 1 This embodiment provides a pump-oscillation integrated narrow linewidth titanium sapphire laser, including:

[0040] Infrared Q-switching unit, used to generate polarized pulsed infrared laser;

[0041] The frequency doubling crystal 107 is used to double the frequency of the infrared laser to obtain a green laser;

[0042] A first plano-concave reflecting mirror 106, used for reflecting green laser light;

[0043] The first polychromatic mirror 201 is located between the infrared Q-switching unit and the frequency doubling crystal 107; it is used to reflect the infrared laser to the frequency doubling crystal 107; it is used to transmit the green laser reflected by the first plano-concave reflector 106 to the titanium sapphire crystal 202;

[0044] The frequency doubling crystal 107 is located between the first polychromatic mirror 201 and the first plano-concave reflecting mirror 106;

[0045] Lens 105, located between the infrared Q-switching unit and the optical path of the first polychromatic mirror 201; used to adjust the waist position of the green laser beam;

[0046] The titanium sapphire crystal 202 is used to generate initial laser light under the pumping action of the green laser light;

[0047] The distance between the green laser beam waist and the first plano-concave reflector 106 is equal to the distance between the first plano-concave reflector 106 and the Ti:Sapphire crystal 202;

[0048] The dispersion element is used to narrow the initial laser line width to obtain the target laser.

[0049] The infrared Q-switching unit, the first polychromatic mirror 201 , the frequency doubling crystal 107 and the first plano-concave reflector 106 constitute a Q-switched green light resonant cavity; the infrared Q-switching unit, the lens 105 , the first polychromatic mirror 201 , the frequency doubling crystal 107 and the first plano-concave reflector 106 together constitute a green light Q-switched laser 100 .

[0050] Since the traditional spot adjustment element is eliminated, the position of the focus is adjusted by adjusting the focal length and position of the lens 105, thereby changing the spot size pumped onto the titanium sapphire crystal. Since the green light is generated by intracavity frequency doubling, the green laser and the infrared laser have the same Gaussian transmission characteristics. Therefore, it is believed that the green laser emitted from the first polychromatic mirror 201 and the infrared laser reflected by the first plano-concave reflector 106 and transmitted back to the lens 105 have the same spatial characteristics, and then the spot size of the output green laser can be adjusted by changing the lens 105, so that when the green laser is incident on the titanium sapphire crystal 202 after being reflected by the first plano-concave reflector 106, the spot of the green laser meets the pumping requirements of the titanium sapphire crystal 202; the overall structure is more compact, the integration is high, and the volume can also be reduced.

[0051] The polarizer 103 in the green Q-switched laser 100 enables the infrared laser to work in a horizontal polarization state, and the frequency doubling crystal 107 converts the horizontally polarized 1053nm infrared laser into a vertically polarized 527nm green laser. The frequency doubling crystal 107 can be a BBO crystal or an LBO crystal, and the conversion method is type I phase matching. The polarizer 103 is made of quartz.

[0052] To further illustrate, the infrared Q-switching unit includes a first plane reflector 101, an infrared laser generating crystal 102, a polarizer 103 and a Q-switching crystal 104 which are arranged in sequence, wherein the infrared laser generating crystal 102 generates an infrared laser with a central wavelength of 1053 nm.

[0053] After being reflected by the first plane reflector 101, the infrared laser passes through the infrared laser generating crystal 102, the polarizer 103, the Q-switched crystal 104, the lens 105, the first polychromatic mirror 201 and the frequency doubling crystal 107 in sequence, wherein the polarizer 103 is arranged at a Briggs angle, so that the infrared laser is frequency-doubled into a green laser with a central wavelength of 527 nm by the frequency doubling crystal 107.

[0054] At this time, a 1053nm high-transmittance film and a 527nm high-transmittance film are selected to be coated on the lens 105, and the lens 105 can be selected to be made of JGS1 material; a 1053nm high-reflection film is coated on the first plane reflector 101, and a 1053nm high-reflection film is coated on the end face of the first polychromatic mirror 201 facing the frequency doubling crystal 107. The incident angle of the infrared laser incident on the first polychromatic mirror 201 is 45°, thereby reflecting the infrared laser to the frequency doubling crystal 107.

[0055] The residual infrared laser that is not converted by the frequency doubling crystal 107 is reflected to the first plane reflector 101 through the first plano-concave reflector 106 and the first polychromatic mirror 201, and oscillates in a cycle to continuously generate 1053nm oscillating laser; at this time, both sides of the infrared laser generating crystal 102 are coated with 1053nm high-transmittance film, both sides of the frequency doubling crystal 107 are coated with 1053nm high-transmittance film and 527nm high-transmittance film, and the first plano-concave reflector 106 is coated with 1053nm high-reflection film and broadband reflection film at the end facing the frequency doubling crystal 107.

[0056] Specifically, the Q-switched crystal 104 can be Q-switched by acousto-optic Q-switching, electro-optic Q-switching or saturated absorber. Preferably, the Q-switched crystal 104 uses a lithium niobate crystal to generate an oscillating laser with a pulse width of 80 ns.

[0057] For example, taking the infrared laser generating crystal 102 with a rod-shaped structure of 80 mm in length and 4 mm in diameter as an example, the distance between the infrared laser generating crystal 102 and the first plane reflector 101 can be selected as 300 mm, and the distance between the infrared laser generating crystal 102 and the lens 105 can be selected as 435 mm. At this time, the distance between the first plane reflector 101 and the lens 105 is 735 mm.

[0058] At the same time, the distance between the lens 105 and the first plano-concave reflector 106 is 400 mm; Figure 2 Under 20mJ green light pumping, a 350μm spot size is used to pump the titanium sapphire crystal 202. The spot size of point A in the cavity is 350μm, and the distance from the lens 105 is 32mm; the distance L between position A and the first plano-concave reflector 106 is 368mm.

[0059] Therefore, the distance between the first plano-concave reflector 106 and the titanium sapphire crystal 202 is 368 mm, the distance between the first polychromatic mirror 201 and the titanium sapphire crystal 202 is 32 mm, and the distance between the first polychromatic mirror 201 and the first plano-concave reflector 106 is 336 mm.

[0060] The green laser generated by the frequency doubling crystal 107 is reflected by the first plano-concave reflector 106 and then incident on the titanium sapphire crystal 202 after the same distance, thereby achieving pumping of the titanium sapphire crystal 202; at this time, a 527nm high-transmittance film is plated on both sides of the end face of the first polychromatic mirror 201 facing the frequency doubling crystal 107.

[0061] Since the frequency doubling crystal 107 obtains a vertically polarized 527nm green laser, in order to meet the pumping requirements for the titanium sapphire crystal 202, the polarization control device 208 is used to change the polarization direction of the green laser to a horizontal direction, and then the green laser is pumped to the titanium sapphire crystal 202, and the titanium sapphire crystal 202 generates an initial laser of 600nm to 1100nm; at this time, a 527nm high-transmittance film is coated on the polarization control device 208, the polarization control device 208 can be selected as a half-wave plate, and the length of the titanium sapphire crystal 202 can be selected as 20mm.

[0062] In order to narrow the line width of the initial laser, further explanation is given by referring to Figure 3 The dispersion element includes a first dispersion prism 203, a second dispersion prism 204 and a third dispersion prism 205 which are arranged in sequence. At this time, the titanium sapphire crystal 202, the first dispersion prism 203, the second dispersion prism 204 and the third dispersion prism 205 are arranged at a Briggs angle. The initial laser passes through the first dispersion prism 203, the second dispersion prism 204 and the third dispersion prism 205 in sequence, and the line width of the initial laser is narrowed to obtain a target laser with a central wavelength of 800nm ​​and a line width of 0.5nm.

[0063] The pump-oscillation integrated narrow linewidth titanium sapphire laser provided in this embodiment further includes an output mirror 207 and a second plano-concave reflector 206, wherein the dispersion element is located between the second plano-concave reflector 206 and the titanium sapphire crystal 202, so that the target laser obtained by the dispersion element passes through the second plano-concave reflector 206, the dispersion element, the titanium sapphire crystal 202, the polarization control device 208 and the first polychromatic mirror 201, and then is output from the output mirror 207. At this time, the first polychromatic mirror 201 is located between the polarization control device 208 and the output mirror 207, and the output mirror 207 is a second end reflector. The second end reflector is coated with a partial reflection film with a transmittance of 30% at 800nm ​​for transmitting the target laser; an 800nm ​​high-reflection film is coated on the end face of the first polychromatic mirror 201 facing the titanium sapphire crystal 202, a 600nm-1100nm broadband high-transmittance film is also coated on the polarization control device 208, and a 600nm-1100nm high-reflection film is coated on the second plano-concave reflector 206.

[0064] The materials of the first dispersion prism 203, the second dispersion prism 204 and the third dispersion prism 205 can all be selected to be SF10 glass, and the curvature radius of the second plano-concave reflector 206 is 1000 mm.

[0065] The second plano-concave reflector 206 is also coated with a 527 nm high-reflection film for reflecting the green laser light that has not pumped the Ti:Sapphire crystal 202 back to the Ti:Sapphire crystal 202 for pumping.

[0066] At this time, the titanium sapphire crystal 202, the dispersion element, the first polychromatic mirror 201 and the output mirror 207, and the second plano-concave reflector 206 together constitute a titanium sapphire resonant cavity, that is, the second plano-concave reflector 206, the dispersion element, the titanium sapphire crystal 202, the polarization control device 208, the first polychromatic mirror 201 and the output mirror 207 together constitute a narrow-linewidth titanium sapphire laser 200.

[0067] refer to Figure 4 This is the distribution diagram of the light spot in the titanium sapphire oscillator cavity. The target laser that does not pass through the output mirror 207 is reflected at 0° and transmitted in the reverse direction. After passing through the first polychromatic mirror 201 and the titanium sapphire crystal 202, it passes through the first dispersion prism 203, the second dispersion prism 204 and the third dispersion prism 205 respectively, and is incident on the second plano-concave reflection mirror 206 at 0° and returns to the output mirror 207 along the original path. Laser resonance is achieved in this cycle, and the radius of the oscillation light spot at the titanium sapphire crystal 202 is 0.367 mm.

[0068] At this time, the optical path distance between the output mirror 207 and the titanium sapphire crystal 202 is 200 mm, and the optical path distance between the titanium sapphire crystal 202 and the second plano-concave reflecting mirror 206 is 300 mm.

[0069] Preferably, the line width of the target laser can be further narrowed by increasing the number of dispersion prisms.

[0070] Example 2

[0071] refer to Figure 5 Different from Example 1, in the pump-oscillation integrated narrow-linewidth titanium sapphire laser provided in this embodiment, the narrow-linewidth titanium sapphire laser 200 includes a fourth plano-concave reflector 400, a dispersion element, a titanium sapphire crystal 202, a polarization control device 208 and a first polychromatic mirror 201.

[0072] Among them, the dispersion element is a transmissive volume Bragg grating, and the transmissive volume Bragg grating serves as an output mirror 207 to output the target laser; at this time, the titanium sapphire crystal 202, the dispersion element, the first polychromatic mirror 201, the output mirror 207 and the fourth plano-concave reflector 400 together constitute a titanium sapphire resonant cavity.

[0073] The transmission volume Bragg grating has an output spectrum bandwidth of 0.2 nm, a central wavelength of 800 nm, a size of 18 mm×18 mm×5 mm, an incident angle of 0°, and a transmittance of 40%.

[0074] The fourth plano-concave reflector 400 is opposite to the titanium sapphire crystal 202, and the titanium sapphire crystal 202 is arranged at a Briggs angle. The end face of the fourth plano-concave reflector 400 facing the titanium sapphire crystal 202 is plated with a 600nm-1100nm high-reflection film. The initial laser generated by the pumping of the titanium sapphire crystal 202 is incident on the fourth plano-concave reflector 400, and then reflected by the fourth plano-concave reflector 400 to the transmission volume Bragg grating, and the transmission volume Bragg grating outputs the target laser.

[0075] Example 3

[0076] refer to Figure 6 , different from Example 1 and Example 2, the pump-oscillation integrated narrow-linewidth titanium sapphire laser provided in this embodiment includes a green light Q-switched laser 100 and a titanium sapphire two-color laser 300, wherein the green light Q-switched laser 100 is the same as that in Example 1, and the titanium sapphire two-color laser 300 includes a first polychromatic mirror 201, a polarization control device 208, a titanium sapphire crystal 202, a dispersion element, a third plane reflector 305 and a third end reflector 209.

[0077] The Ti:Sapphire crystal 202, the dispersion element, the first polychromatic mirror 201, the third end reflector 209, the third plane reflector 305 and the fourth plane reflector 306 together form a Ti:Sapphire resonant cavity.

[0078] To further illustrate, the dispersion element includes a diffraction grating 303 and a fourth dispersion prism 304, and the titanium sapphire crystal 202, the diffraction grating 303, the fourth dispersion prism 304 and the third plane reflector 305 are arranged in sequence. At this time, the green laser that pumps the titanium sapphire crystal 202 through the polarization control device 208 is vertically incident on the end face of the titanium sapphire crystal 202, and the end face of the titanium sapphire crystal 202 is cut at a right angle; the diffraction grating 303 is arranged at a Briggs angle, and the role of the intracavity polarization control device 208 of the titanium sapphire two-color laser 300 is to adjust the green mechanism to horizontal polarization so that it meets the π polarization absorption of the titanium sapphire crystal and improves the utilization rate of the pump light. Secondly, it is to adjust the target laser to horizontal polarization so that it meets the grating diffraction condition.

[0079] Specifically, the initial laser light generated by the titanium sapphire crystal 202 is separated in space by the diffraction grating 303 and the fourth dispersion prism 304, thereby generating a target laser light with a narrow line width, and the 0th order light of the diffraction grating 303 is emitted as the target laser light.

[0080] At this time, the diffraction grating 303 has 1200 lines / mm and a size of 12.7mm×12.7mm×6mm; the fourth dispersion prism 304 can also be made of SF10 glass, and the end face of the third plane reflector 305 facing the fourth dispersion prism 304 is coated with a 600nm-1100nm high reflection film.

[0081] Further preferably, the titanium sapphire two-color laser 300 also includes a fourth plane mirror 306, and the fourth plane mirror 306 and the third plane mirror 305 are located on the same side of the fourth dispersion prism 304. The optical path between the fourth plane mirror 306 and the fourth dispersion prism 304 does not overlap with the optical path between the third plane mirror 305 and the fourth dispersion prism 304. Therefore, the target laser wavelengths incident on the fourth plane mirror 306 and the third plane mirror 305 are different and the difference is small. For example, the target laser wavelengths are 800.3nm and 800.4nm respectively, thereby realizing small wavelength difference two-color laser (target laser) output.

[0082] The end surface of the fourth plane reflector 306 facing the fourth dispersion prism 304 is also coated with a 600nm-1100nm high reflection film, and the end surface of the third end reflector 209 facing the first polychromatic mirror 201 is also coated with a 600nm-1100nm high reflection film.

[0083] To further illustrate, the titanium sapphire two-color laser 300 also includes a third plano-concave reflector 301 and a second polychromatic mirror 302. The residual green laser that is not completely absorbed by the titanium sapphire crystal 202 is incident on the third plano-concave reflector 301 through the second polychromatic mirror 302, and then re-pumps the titanium sapphire crystal 202 through the third plano-concave reflector 301.

[0084] At this time, the second polychromatic mirror 302 is coated with a 527nm high-reflection film on the side facing the titanium sapphire crystal 202, and is coated with a 600nm-1100nm high-transmittance film on both sides; the end face of the third plano-concave reflector 301 facing the second polychromatic mirror 302 is coated with a 527nm high-reflection film, and the curvature radius of the third plano-concave reflector 301 is 300mm.

[0085] Specifically, the two-color laser is reflected by the first polychromatic mirror 201 to the third end reflector 209, transmitted in the reverse direction through 0° reflection, and diffracted by the diffraction grating 303 after passing through the second polychromatic mirror 302. The first-order diffraction light is further separated in space by the fourth dispersion prism 304. The two-color laser is respectively incident on the third plane reflector 305 and the fourth plane reflector 306 at 0°, returns to the titanium sapphire crystal 202 along the original path and continues to oscillate, and the 0th-order diffraction light incident on the diffraction grating 303 is emitted; the angles of the third plane reflector 305 and the fourth plane reflector 306 are adjusted to achieve wavelength tuning.

[0086] The above is the embodiment of the present application. The above embodiments and the specific parameters in the embodiments are only for the purpose of clearly describing the verification process of the invention, and are not intended to limit the patent protection scope of the present invention. The patent protection scope of the present invention is still subject to its claims, and any equivalent structural changes made by using the contents of the description and drawings of the present invention should be included in the protection scope of the present invention.

Claims

1. A pump-oscillation integrated narrow linewidth titanium sapphire laser, characterized in that: include: Infrared Q-switching unit, used to generate infrared laser; A frequency doubling crystal (107) is used to perform frequency doubling of infrared laser to obtain green laser; A first plano-concave reflecting mirror (106), used for reflecting green laser light; A first polychromatic mirror (201) is located between the infrared Q-switching unit and the frequency doubling crystal (107); used to reflect infrared laser light to the frequency doubling crystal (107); and used to transmit green laser light reflected by the first plano-concave reflecting mirror (106) to the titanium sapphire crystal (202); The frequency doubling crystal (107) is located between the first polychromatic mirror (201) and the first plano-concave reflecting mirror (106); The lens (105) is located between the infrared Q-switching unit and the optical path of the first polychromatic mirror (201); and is used to adjust the waist position of the green laser beam; A titanium sapphire crystal (202), used to generate initial laser light under the pumping action of green laser light; The dispersion element is used to narrow the initial laser line width to obtain the target laser.

2. The pump-oscillation integrated narrow linewidth Ti:sapphire laser according to claim 1, characterized in that: The infrared Q-switching unit comprises a first plane reflector (101), an infrared laser generating crystal (102), a polarizer (103) and a Q-switching crystal (104) which are arranged in sequence, and the lens (105) is located between the Q-switching crystal (104) and the first polychromatic mirror (201).

3. The pump-oscillation integrated narrow linewidth Ti:sapphire laser according to claim 2, characterized in that: The pump-oscillation integrated narrow linewidth titanium sapphire laser also includes a polarization control device (208) for adjusting the polarization direction of the green laser reflected by the first plano-concave reflector (106); the polarization control device (208) is located between the first polychromatic mirror (201) and the titanium sapphire crystal (202).

4. The pump-oscillation integrated narrow linewidth Ti:sapphire laser according to claim 3, characterized in that: The pump-oscillation integrated narrow linewidth titanium sapphire laser also includes an output mirror (207), the output mirror (207) is used to emit target laser light, and the first polychromatic mirror (201) is located between the output mirror (207) and the polarization control device (208).

5. The pump-oscillation integrated narrow linewidth Ti:sapphire laser according to claim 4, characterized in that: The dispersion element comprises a first dispersion prism (203), a second dispersion prism (204) and a third dispersion prism (205) which are arranged in sequence; The titanium sapphire crystal (202), the first dispersion prism (203), the second dispersion prism (204) and the third dispersion prism (205) are all arranged at a Briggs angle, and the output mirror (207) is a second end face reflection mirror.

6. The pump-oscillation integrated narrow linewidth Ti:sapphire laser according to claim 3, characterized in that: The dispersion element is shared with an output mirror (207), the output mirror (207) is a transmission volume Bragg grating, the pump-oscillation integrated narrow linewidth titanium sapphire laser further comprises a fourth plano-concave reflector (400), the titanium sapphire crystal (202) is located between the fourth plano-concave reflector (400) and the polarization control device (208), the first polychromatic mirror (201) is located between the output mirror (207) and the polarization control device (208), and the titanium sapphire crystal (202) is arranged at a Briggs angle.

7. The pump-oscillation integrated narrow linewidth Ti:sapphire laser according to claim 3, characterized in that: The dispersion element comprises a diffraction grating (303) and a fourth dispersion prism (304); the pump-oscillation integrated narrow linewidth titanium sapphire laser further comprises a third plane reflector (305) and a third end reflector (209); the first polychromatic mirror (201) is located between the third end reflector (209) and the polarization control device (208); the titanium sapphire crystal (202), the diffraction grating (303), the fourth dispersion prism (304) and the third plane reflector (305) are arranged in sequence; The diffraction grating (303) is used to reflect the initial laser to the fourth dispersion prism (304), and the fourth dispersion prism (304) is arranged at a Briggs angle. By adjusting the angle between the third plane reflection mirror (305) and the fourth dispersion prism (304), the target laser to be reflected is determined; and the diffraction grating (303) is also used to output the target laser reflected by the third plane reflection mirror (305).

8. The pump-oscillation integrated narrow linewidth Ti:sapphire laser according to claim 7, characterized in that: The dispersion element further comprises a fourth plane reflector (306), wherein the fourth plane reflector (306) and the third plane reflector (305) are located on the same side of the fourth dispersion prism (304), and the fourth plane reflector (306) and the third plane reflector (305) are arranged at intervals around the fourth dispersion prism (304).

9. The pump-oscillation integrated narrow linewidth Ti:sapphire laser according to claim 8, characterized in that: The pump-oscillation integrated narrow linewidth titanium sapphire laser further comprises a third plano-concave reflector (301) and a second polychromatic mirror (302), wherein the second polychromatic mirror (302) is arranged between the titanium sapphire crystal (202) and the diffraction grating (303); The second polychromatic mirror (302) is used to transmit the initial laser light and also to reflect the green laser light to the third plano-concave reflecting mirror (301).

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