阅读说明：本技术 紧凑型固体激光器 (Compact solid laser ) 是由 刘兰 廖若杭 余竞雄 于 2020-05-12 设计创作，主要内容包括：紧凑型固体激光器,涉及脉冲式固体激光器领域。包括激光器腔体和设于激光器腔体内的脉冲激光产生模块；脉冲激光产生模块沿腔体中轴线依次排布有激光二极管、光束整形器、聚焦透镜、工作物质和饱和吸收体。还包括激光波长选择模块,激光波长选择模块置于饱和吸收体之后。激光波长选择模块沿腔体中轴线设有倍频晶体和合频晶体(可通过改变晶体配置情况更改输出激光波长)。引入激光二极管泵浦与被动调Q技术,结构简单紧凑,可输出具有固定频率且脉冲宽度小于1ns的脉冲激光。实现脉冲式固体激光器的小型化,具备稳定简单的结构与高效的泵浦光利用率,使用便携稳定,其窄脉宽的特征在医疗与检测领域具有应用潜力。(Compact solid laser relates to pulsed solid laser field. The laser comprises a laser cavity and a pulse laser generation module arranged in the laser cavity; the pulse laser generating module is provided with a laser diode, a beam shaper, a focusing lens, a working substance and a saturable absorber in sequence along the central axis of the cavity. The laser wavelength selection module is arranged behind the saturable absorber. The laser wavelength selection module is provided with a frequency doubling crystal and a frequency combining crystal (the output laser wavelength can be changed by changing the crystal configuration) along the central axis of the cavity. The laser diode pumping and passive Q-switching technology is introduced, the structure is simple and compact, and the pulse laser with fixed frequency and pulse width less than 1ns can be output. The pulse type solid laser has the advantages of realizing miniaturization of the pulse type solid laser, having a stable and simple structure and high-efficiency pump light utilization rate, being portable and stable in use, and having application potential in the medical and detection fields due to the characteristic of narrow pulse width.)

1. Compact solid state laser, its characterized in that: the laser comprises a laser cavity and a pulse laser generation module arranged in the laser cavity; the pulse laser generating module is sequentially provided with a laser diode, a beam shaper, a focusing lens, a working substance and a saturable absorber along the central axis of the cavity.

2. A compact solid state laser as in claim 1 wherein: the laser wavelength selection module is arranged behind the saturable absorber.

3. A compact solid state laser as claimed in claim 2 wherein: the laser wavelength selection module is provided with a frequency doubling crystal or a frequency combining crystal along the central axis of the cavity, or the laser wavelength selection module is sequentially provided with the frequency doubling crystal and the frequency combining crystal along the central axis of the cavity.

4. A compact solid-state laser as claimed in claim 3 wherein said frequency doubling crystal is BBO crystal and said frequency combining crystal is L BO crystal.

5. A compact solid state laser as in claim 1 wherein: the working substance adopts Nd: YAG (yttrium aluminum garnet)A crystal; the saturable absorber adopts Cr⁴⁺YAG crystal.

6. A compact solid state laser as in claim 1 wherein: the beam shaper is a micromirror prism stack formed by rotationally arranging a plurality of cuboid K9 quartz glass at intervals of the middle points of edges.

7. A compact solid state laser as in claim 6 wherein: the K9 quartz glass is provided with 6 quartz glass sheets, and the interval angle between adjacent K9 quartz glass sheets is 10 degrees.

8. A compact solid state laser as in claim 6 wherein: the length, width and height of the K9 quartz glass are 15cm x 0.5 cm.

9. A compact solid state laser as in claim 6 wherein: six surfaces of the K9 quartz glass are polished.

10. A compact solid state laser as in claim 1 wherein: the laser cavity is the setting of cuboid, and the length of laser cavity is not more than 25 cm.

Technical Field

The invention relates to the field of pulse type solid lasers, in particular to a compact type solid laser.

Background

Since the first ruby laser in the world was produced in 1960, laser technology has been vigorously developed. The pulse laser has the advantages of short pulse width, wide spectral range, high peak power and adjustable repetition frequency, and is widely applied to the fields of industrial processing, material treatment, medical treatment, scientific research and the like. Compared with a continuous laser, the interaction time of the pulse laser and the material is very short, the thermal effect is obviously reduced, and the laser is more suitable for application scenes with high precision and low damage.

The key of the pulse laser technology lies in the selection of a pumping source and a working medium and the acquisition of high peak power by the technologies of Q-switching technology, mode locking and the like. The appearance of the laser diode pumping technology solves the problems of complex structure and low energy utilization efficiency of the traditional lamp pumping laser. The laser diode is a small laser, the working substance is a PN junction (or PIN junction) made of semiconductor material, the excitation mode usually adopts an electric excitation mode, and the laser diode has the characteristics of small size and good monochromaticity of light beams. The laser diode pumping technology applied to laser design can effectively reduce the design difficulty of the laser pump and the overall size of the laser, and improve the energy utilization efficiency.

The Q-switching technology concentrates and compresses dispersed laser energy to release in a short time by modulating a quality factor (Q value) of a resonant cavity and outputs in a giant pulse mode, and the pulse width of the pulse light is narrow, and meanwhile, the peak power is high. The Q-switching technology can be divided into active Q-switching and passive Q-switching, wherein the passive Q-switching technology realized by the nonlinear optical crystal has the advantages of small volume, easy transportation, high efficiency and the like.

Currently, laser suppliers mainly aim to provide pulsed lasers with high peak power, and there are few low-energy pulsed laser products more suitable for detection and medical treatment, which limits the development of practical applications of pulsed lasers.

Disclosure of Invention

The invention aims to solve the problems in the prior art, provides a compact solid laser, introduces laser diode pumping and passive Q-switching technology, has simple and compact structure, and can output pulse laser with fixed frequency and pulse width less than 1 ns.

In order to achieve the purpose, the invention adopts the following technical scheme:

the compact solid laser comprises a laser cavity and a pulse laser generating module arranged in the laser cavity; the pulse laser generating module is sequentially provided with a laser diode, a beam shaper, a focusing lens, a working substance and a saturable absorber along the central axis of the cavity.

The invention also includes a laser wavelength selection module disposed behind the saturable absorber.

The laser wavelength selection module is provided with a frequency doubling crystal or a frequency combining crystal along the central axis of the cavity, or the laser wavelength selection module is sequentially provided with the frequency doubling crystal and the frequency combining crystal along the central axis of the cavity.

The frequency doubling crystal adopts BBO crystal, and the frequency combining crystal adopts L BO crystal.

The working substance adopts Nd: YAG crystal; the saturable absorber adopts Cr⁴⁺YAG crystal.

The beam shaper is a micromirror prism stack formed by rotationally arranging a plurality of cuboid K9 quartz glass at intervals of the middle points of edges.

The K9 quartz glass is provided with 6 quartz glass sheets, and the interval angle between adjacent K9 quartz glass sheets is 10 degrees.

The length, width and height of the K9 quartz glass are 15cm x 0.5 cm.

Six surfaces of the K9 quartz glass are polished.

The laser cavity is the setting of cuboid, and the length of laser cavity is not more than 25 cm.

Compared with the prior art, the technical scheme of the invention has the following beneficial effects:

1. the laser resonant cavity of the invention consists of a working substance (Nd: YAG) and a saturable absorber (Cr)⁴⁺YAG) in a working substance (Nd: YAG) is followed by a saturable absorber (Cr)⁴⁺YAG) when the 1064nm laser energy reaches the threshold of the saturable absorber, the energy is quickly released within 1ns, a giant pulse is generated, and passive Q-switching is realized.

2. The laser wavelength selection module can selectively output laser with three wavelengths including 1064nm (without frequency doubling crystal and frequency combining crystal), 532nm (only frequency doubling crystal) and 355nm (both frequency doubling crystal and frequency combining crystal) by changing the configuration of the laser wavelength selection module.

3. The nanosecond solid laser is simple in structure, compact in whole and small in size, all accessories are assembled in a cuboid laser cavity with the length of 25cm, miniaturization of the pulse type solid laser is achieved, the nanosecond solid laser has a stable and simple structure and high-efficiency pump light utilization rate, the nanosecond solid laser is portable and stable to use, and the characteristic of narrow pulse width (1ns) of the nanosecond solid laser has application potential in the field of medical treatment and detection.

Drawings

FIG. 1 is a schematic structural view of example 1;

FIG. 2 is a schematic structural view of example 2;

FIG. 3 is a schematic structural diagram of a beam shaper;

fig. 4 is a schematic diagram of a beam shaping transformation for beam shaping.

Reference numerals: the laser comprises a 1-laser diode, a 2-beam shaper, 21-K9 quartz glass, a 3-focusing lens, a 4-working substance, a 5-saturated absorber, a 6-frequency doubling crystal and a 7-frequency combining crystal, wherein the I part is a laser generation module, and the II part is a wavelength selection module.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects of the present invention clearer and clearer, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.