CN210040867U

CN210040867U - Picosecond laser amplifier

Info

Publication number: CN210040867U
Application number: CN201920768422.1U
Authority: CN
Inventors: 陈曦; 陈磊; 王东贺
Original assignee: Changchun New Industries Photoelectric Technology Co Ltd
Current assignee: Changchun New Industries Photoelectric Technology Co Ltd
Priority date: 2019-05-27
Filing date: 2019-05-27
Publication date: 2020-02-07
Anticipated expiration: 2029-05-27

Abstract

The utility model relates to a picosecond laser amplifier, its characterized in that, the laser that the seed source produced pours into seed light in proper order and leads into device, amplification chamber and first pump light source triplex, and wherein the leading-in device of seed light is leading-in amplification chamber behind the laser plastic that produces the seed source, and first pump light source provides pump power for amplification chamber, enlargies the laser that the seed source produced. The picosecond seed laser is amplified by adopting a multi-pass amplification mode, so that the high price caused by using a Pockels cell is avoided, and the interference of overhigh half-wave voltage on a system is avoided; in addition, the pockels cell is easy to damage a film layer when being used in an environment with overhigh peak power for a long time, and the pockels cell is not used for amplification, so that the stability of the laser is improved.

Description

Picosecond laser amplifier

Technical Field

The utility model relates to a picosecond laser amplifier belongs to an all solid-state laser technical field.

Background

In recent years, ultrashort pulse lasers with high repetition rate and high average power have been used in many fields, such as medical treatment, material processing, satellite ranging, and the like. However, the picosecond laser pulse repetition frequency is strictly dependent on the cavity length, the longer the resonant cavity, the lower the pulse repetition frequency. High energy picosecond laser pulses with repetition frequencies of kilohertz (kHz) and energies on the order of microjoules (muj) are often required in the fields of laser machining, bioscience, and the like. The length of a resonant cavity of a common mode-locked laser is 1-2 m, and the repetition frequency is generally in the order of hundred megahertz, so that the single pulse energy is usually not high and is mostly in the order of nanojoules (nJ), and therefore, the single pulse energy needs to be amplified to the required pulse energy by an amplifier to meet the application requirement.

An all-solid-state picosecond laser pulse regeneration amplifier is proposed in a utility model patent CN103022886A which is published in 2013, 1 month and 5 days, and comprises a seed source; seed light leading-in and amplified light leading-out devices composed of a first thin film polarizing plate, a second thin film polarizing plate, a Faraday rotator and a lambda/2 wave plate; a first pump light source; a regeneration chamber; the two cavity mirrors of the regeneration cavity comprise a first concave mirror and a second concave mirror, and a Pockels cell, a first lambda/4 wave plate, a third film polaroid, a fourth film polaroid and a third concave mirror are sequentially arranged in the regeneration cavity along the light propagation direction. The laser device comprises a first convex mirror, a first laser crystal, a second convex mirror and a fourth concave mirror, wherein the first laser crystal is Yb: YAG rod. Although the pockels cell has a simple structure and can achieve the required amplification effect, the pockels cell is expensive, the driving voltage is generally more than 2000V, and the pockels cell is easy to interfere with other electronic components in a system in the application of laser radar and the like.

Disclosure of Invention

To the weak point of above-mentioned technique, the utility model aims to provide a picosecond laser amplifier, wherein the amplifier part adopts the multipass structure of amplification, can not realize the 1064nm skin laser of high monopulse energy like this through regeneration amplification mode.

In order to achieve the above object, the technical solution of the present invention is that: a picosecond laser amplifier comprising a seed source; the seed light guide device consists of a first biconcave mirror, a first plano-convex mirror, a half-wave plate and a Faraday rotator; a first pump light source; an amplification chamber; the amplification cavity comprises a first concave mirror, a first plane mirror, a second concave mirror, a third plane mirror, a first laser crystal, a fourth plane mirror, a fifth plane mirror, a sixth plane mirror, a seventh plane mirror and an eighth plane mirror, and is characterized in that laser generated by a seed source is injected into a seed light introduction device, the amplification cavity and a first pump light source in sequence, wherein the seed light introduction device shapes the laser generated by the seed source and then introduces the laser into the amplification cavity, and the first pump light source provides pump power for the amplification cavity to amplify the laser generated by the seed source; the first laser crystal is Nd: YVO₄A crystal; the first pumping light source is composed of a first semiconductor laser, a first collimating mirror, a first deflecting prism and a first focusing mirror in sequence, and the first pumping light source is 808 nmLD.

The seed light leading-in device is sequentially provided with a first biconcave mirror, a first plano-convex mirror, a half-wave plate and a 45-degree Faraday optical rotator along the laser injection direction of a seed source, the first biconcave mirror and the first plano-convex mirror shape laser generated by the seed source, and the half-wave plate and the 45-degree Faraday optical rotator isolate laser returned by an amplification cavity.

The first pumping light source provides pumping power for the amplifying cavity.

The amplification cavity light path is characterized in that laser generated by the seed source 1 is injected into a first concave mirror, a first plane mirror, a second concave mirror, a third plane mirror, a first laser crystal, a fourth plane mirror, a fifth plane mirror, a sixth plane mirror, a seventh plane mirror and an eighth plane mirror in sequence through a seed light introduction device, the injected seed laser is amplified after being reflected by the above mirrors in sequence and passing through the first laser crystal for multiple times in the cavity, and is output through the eighth plane mirror; the first pumping light source is positioned on the left side of the third plane mirror, and the first laser crystal is arranged on the right side of the third plane mirror and is used for amplifying laser generated by the seed source.

Compared with the prior art, the utility model has the advantages that the picosecond seed laser is amplified by adopting a multi-pass amplification mode, thereby avoiding the high price caused by using a Pockels cell and the interference of the over-high half-wave voltage to the system; in addition, the pockels cell is easy to damage a film layer when being used in an environment with overhigh peak power for a long time, and the pockels cell is not used for amplification, so that the damage of devices is reduced while the same amplification effect is achieved, and the stability and the service life of the laser are improved.

Drawings

Fig. 1 is a schematic structural diagram of the picosecond laser amplifier of the present invention.

Fig. 2 shows the Nd of the present invention: YVO₄Absorption lines of the crystals.

Fig. 3 shows the Nd of the present invention: YVO₄Absorption lines of the crystals.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings; as shown in fig. 1, a picosecond laser amplifier comprises a seed source 100; a seed light introduction means composed of a first biconcave mirror 101, a first plano-convex mirror 102, a half-wave plate 201 and a Faraday rotator 202; a first pump light source; an amplification chamber; the amplification cavity comprises a first concave mirror 301, a first plane mirror 302, a second concave mirror 303, a third plane mirror 304, a first laser crystal 305, a fourth plane mirror 306, a fifth plane mirror 307, a sixth plane mirror 308, a seventh plane mirror 309 and an eighth plane mirror 310, and is characterized in that laser generated by the seed source 100 is injected into a seed light introduction device, the amplification cavity and a first pump light source in sequence, wherein the seed light introduction device shapes the laser generated by the seed source 100 and then introduces the laser into the amplification cavity, and the first pump light source provides pump power for the amplification cavity to amplify the laser generated by the seed source 100; the first laser crystal 305 is Nd: YVO₄A crystal; the first pump light source is composed of a first semiconductor laser 404, a first collimating mirror, a first deflecting prism 402 and a first focusing mirror in sequence; the first pump light source is 808nm LD.

The seed light guide-in device 100 is sequentially provided with a first biconcave mirror 101, a first plano-convex mirror 102, a half-wave plate 201 and a 45-degree Faraday optical rotator 202 along the injection direction of seed source laser, the first biconcave mirror 101 and the first plano-convex mirror 102 shape the laser generated by the seed source 100, and the half-wave plate 201 and the 45-degree Faraday optical rotator 202 isolate the laser returned from the seed source 100 by the amplification cavity.

The first pump light source 3 provides pump power for the amplification chamber.

The amplification cavity optical path is that laser generated by the seed source 100 is injected into a first concave mirror 301, a first plane mirror 302, a second concave mirror 303, a third plane mirror 304, a first laser crystal 305, a fourth plane mirror 306, a fifth plane mirror 307, a sixth plane mirror 308, a seventh plane mirror 309 and an eighth plane mirror 310 in sequence through a seed light introduction device, the injected seed laser is amplified after being reflected by the above mirrors for multiple times in the cavity sequentially and passing through the first laser crystal 305, and is output through the eighth plane mirror 310; the first pump light source is located at the left side of the third plane mirror 304, and the first laser crystal 305 is located at the right side, and amplifies the laser generated by the seed source 100.

Laser generated by a seed source 100 is shaped into a proper light spot and a proper divergence angle through a first biconcave mirror 101 and a first plano-convex mirror 102 in a seed light guide-in device and enters an amplification cavity, a half-wave plate 201 and a 45 DEG Faraday optical rotator 202 in the seed light guide-in device are used for preventing amplified laser from returning to the seed source 100 due to insufficient transmittance of lenses to damage the seed source, the seed laser entering the amplification cavity sequentially passes through all total reflection mirrors between a first concave mirror 301 and a seventh plane mirror 309 and passes through a first laser crystal 305 for multiple times, pump energy is taken away from the first laser crystal 305 to be amplified, and finally the seed laser is output through an eighth plane mirror 310, a first semiconductor laser 404 in the first pump source provides pump energy for the laser crystal, a second plano-convex mirror 401, a first deflection prism 402 and a third plano-convex mirror 403 are used for shaping and guiding the pump light generated by the first semiconductor laser 404 into the laser crystal, the pumping light spots are matched with the spot modes in the amplification cavity and completely overlapped in position, so that the maximum amplification efficiency is achieved.

As shown in fig. 2 and 3, Nd: YVO₄The crystal is a laser crystal with excellent performance and is suitable for preparationLaser diode pumping is made especially for medium and low power lasers. Has the characteristics of low light damage threshold, high slope efficiency, uniaxial crystal and linearly polarized light output. The utility model discloses a Nd: YVO₄The crystal replaces Nd-YAG crystal because of Nd-YVO compared with Nd-YAG crystal₄The crystal has higher absorption coefficient and larger stimulated emission cross section to the pump light, and the pump bandwidth is about 5 times of Nd: YAG at about 808 nm.

In the present invention, the first laser crystal 305 is preferably an Nd: YAG crystal.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. A picosecond laser amplifier comprising a seed source; the seed light guide device consists of a first biconcave mirror, a first plano-convex mirror, a half-wave plate and a Faraday rotator; a first pump light source; an amplification chamber; the amplification cavity comprises a first concave mirror, a first plane mirror, a second concave mirror, a third plane mirror, a first laser crystal, a fourth plane mirror, a fifth plane mirror, a sixth plane mirror, a seventh plane mirror and an eighth plane mirror, and is characterized in that laser generated by the seed source 1 is injected into a seed light introduction device, the amplification cavity and a first pump light source in sequence, wherein the seed light introduction device shapes the laser generated by the seed source and then introduces the laser into the amplification cavity, and the first pump light source provides pump power for the amplification cavity to amplify the laser generated by the seed source; the first laser crystal is Nd: YVO₄A crystal; the first pumping light source is composed of a first semiconductor laser, a first collimating mirror, a first deflecting prism and a first focusing mirror in sequence, and the first pumping light source is an LD with the wavelength of 808 nm.

2. The picosecond laser amplifier according to claim 1, wherein the seed light guide device is sequentially provided with a first biconcave mirror, a first plano-convex mirror, a half-wave plate and a 45 ° faraday optical rotator along the laser injection direction of the seed source, the first biconcave mirror and the first plano-convex mirror shape the laser generated by the seed source, and the half-wave plate and the 45 ° faraday optical rotator isolate the laser from the amplification cavity and return to the seed source.

3. The picosecond laser amplifier of claim 1 wherein said first pump light source provides pump power to the amplification chamber.

4. The picosecond laser amplifier of claim 1, wherein the optical path of the amplification chamber is such that the laser generated by the seed source is injected into the first concave mirror, the first plane mirror, the second concave mirror, the third plane mirror, the first laser crystal, the fourth plane mirror, the fifth plane mirror, the sixth plane mirror, the seventh plane mirror, and the eighth plane mirror in sequence through the seed light introduction device, and the injected seed laser is amplified after passing through the first laser crystal multiple times after sequentially passing through the above mirrors in the chamber and is output through the eighth plane mirror; the first pumping light source is positioned on the left side of the third plane mirror, and the first laser crystal is arranged on the right side of the third plane mirror and is used for amplifying laser generated by the seed source.