阅读说明：本技术 一种用于激光测距的无温控宽温区高效运行的调q激光器 (A transfer Q laser instrument that is used for high-efficient operation of no control by temperature change wide-temperature range of laser rangefinder ) 是由 李小青 冯新 张洪流 王能东 赵玉倩 崔家珮 李磊 王能礼 于 2020-03-20 设计创作，主要内容包括：本发明提供了一种用于激光测距的无温控宽温区高效运行的调Q激光器,包括：控制模块、电源模块、激光模块和光学系统；控制模块包括信息处理器、出光探测器和探测器雪崩光电二极管；控制模块分别连接电源模块和激光模块；电源模块分别连接控制模块和泵浦模块；光学系统包括发射光学系统和接收光学系统；出光探测器采集激光模块发射的经发射光学系统压缩后射向被测目标的激光,并将激光整形后传递至信息处理器并启动计时；接收光学系统将从被测目标发射的激光会聚至探测器雪崩光电二极管,雪崩光电二极管输出的回波信号经放大整形后送信息处理器并停止计时。(The invention provides a Q-switched laser device for high-efficiency operation of a temperature-control-free wide temperature area for laser ranging, which comprises: the device comprises a control module, a power supply module, a laser module and an optical system; the control module comprises an information processor, a light-emitting detector and a detector avalanche photodiode; the control module is respectively connected with the power supply module and the laser module; the power supply module is respectively connected with the control module and the pumping module; the optical system comprises a transmitting optical system and a receiving optical system; the light-emitting detector collects laser emitted by the laser module and compressed by the emission optical system and emitted to a detected target, shapes the laser and transmits the shaped laser to the information processor, and starts timing; the receiving optical system converges the laser emitted from the measured target to the detector avalanche photodiode, and the echo signal output by the avalanche photodiode is amplified, shaped and sent to the information processor to stop timing.)

1. A transfer Q laser instrument that is used for high-efficient operation of no control by temperature change wide warm area of laser rangefinder, its characterized in that includes: the device comprises a control module, a power supply module, a laser module and an optical system; the control module comprises an information processor, a light-emitting detector and a detector avalanche photodiode; the control module is respectively connected with the power supply module and the laser module; the power supply module is respectively connected with the control module and the pumping module; the optical system comprises a transmitting optical system and a receiving optical system; the light-emitting detector collects laser emitted by the laser module and compressed by the emission optical system and emitted to a detected target, shapes the laser and transmits the shaped laser to the information processor, and starts timing; the receiving optical system converges the laser emitted from the measured target to the detector avalanche photodiode, and the echo signal output by the avalanche photodiode is amplified, shaped and sent to the information processor to stop timing.

2. The temperature-free wide-temperature-zone high-efficiency-operation Q-switched laser for laser ranging as defined in claim 1, wherein the laser module comprises a total reflection mirror, a pumping module, a Q-switching module and an output mirror.

3. The temperature-free temperature-controlled wide-temperature-range high-efficiency Q-switched laser for laser ranging according to claim 1 or 2, wherein the pumping module comprises a working substance and a VCSEL pumping source, and the working substance generates irregular polarized light under the excitation of the VCSEL pumping source.

4. The Q-switched laser with the temperature-free and high-efficiency operation in the wide temperature range for laser ranging as claimed in claim 3, wherein the Q-switched module comprises a polarizer, an 1/4 wave plate and a Q-switched crystal, and the polarizer, the 1/4 wave plate and the Q-switched crystal are sequentially arranged, so that randomly polarized light generated by the working substance under the excitation of the VCSEL pump source is changed into linearly polarized light through the polarizer, then the linearly polarized light is incident to the holophote through the 1/4 wave plate and the Q-switched crystal, and after being reflected by the holophote, the incident light passes through the Q-switched crystal and the 1/4 wave plate, and the reverse light passes through the polarizer again.

5. The temperature-control-free wide-temperature-zone high-efficiency-operation Q-switched laser for laser ranging according to claim 1 or 2, characterized in that the working substance is Nd: YAG.

6. The temperature-control-free wide-temperature-zone high-efficiency Q-switched laser for laser ranging as defined by claim 1 or 2, wherein the polarizer is a thin-film polarizing beam splitter prism.

7. The temperature-free temperature-controlled wide-temperature-zone high-efficiency-operation Q-switched laser for laser ranging according to claim 1 or 2, characterized in that the Q-switched crystal is a Lithium Niobate (LN) crystal.

8. The temperature-free wide-temperature-zone high-efficiency Q-switched laser for laser ranging of claim 3, wherein the Q-switching module comprises a Q-switching crystal.

9. The temperature-free wide-temperature-range high-efficiency Q-switched laser for laser ranging as defined in claim 1 or 2, wherein the Q-switched crystal is Cr⁴⁺: YAG crystal.

Technical Field

The invention relates to the field of lasers, in particular to a Q-switched laser which is used for laser ranging and operates efficiently in a temperature-control-free wide temperature range.

Background

The all-solid-state laser of the semiconductor laser pump is widely applied to the field of laser ranging because of the narrow pulse width and high peak power. Among the existing lasers for Laser ranging, an Edge Emitting semiconductor Laser (EEL) is generally used for pumping, the area of a light Emitting region is small, the power density is large, an emission spectrum is sensitive to temperature change, and the emission center wavelength is generally 0.3 nm/DEG C along with the temperature change. The gain medium used for absorbing the pump laser and generating the resonance laser has large variation of laser absorption coefficients of different wavelengths. When a common edge-emitting laser is used as a pumping source, in order to obtain stable output, a semiconductor refrigerator or a water cooling active mode or other active modes are often used for accurately controlling the temperature of the pumping source, so that the volume, the weight and the power consumption of the whole machine are increased, and the reliability of the whole machine is also greatly reduced.

Compared with a side-emitting semiconductor laser, a Vertical-cavity surface-emitting semiconductor laser (VCSEL) has the advantages of low cost, high reliability, capability of being used in a wide temperature range, extremely small emission spectrum width, uniformly distributed round light beams with small divergence angles, and the like. In particular, the VCSEL has a weak sensitivity of the center of the emission spectrum to temperature, and the coefficient of the temperature drift of the center wavelength of the emission spectrum is only 0.07 nm/DEG C. As Nd: when the YAG crystal is used as a pumping source, compared with an edge-emitting laser, the requirement on temperature control can be greatly reduced, and stable laser output can be realized under the condition of no active temperature control.

Disclosure of Invention

The invention aims to solve the technical problem of the prior art and provides a Q-switched laser which can realize the high-efficiency operation of stable laser output under the condition of no active temperature control.

The invention provides a Q-switched laser device for high-efficiency operation of a temperature-control-free wide temperature area for laser ranging, which comprises: the device comprises a control module, a power supply module, a laser module and an optical system; the control module comprises an information processor, a light-emitting detector and a detector avalanche photodiode; the control module is respectively connected with the power supply module and the laser module; the power supply module is respectively connected with the control module and the pumping module; the optical system comprises a transmitting optical system and a receiving optical system; the light-emitting detector collects laser emitted by the laser module and compressed by the emission optical system and emitted to a detected target, shapes the laser and transmits the shaped laser to the information processor, and starts timing; the receiving optical system converges the laser emitted from the measured target to the detector avalanche photodiode, and the echo signal output by the avalanche photodiode is amplified, shaped and sent to the information processor to stop timing.

Preferably, the laser module comprises a total reflection mirror, a pumping module, a Q-switching module and an output mirror.

Preferably, the pumping module comprises an operating substance and a VCSEL pumping source, and the operating substance generates randomly polarized light under the excitation of the VCSEL pumping source.

Preferably, the Q-switched module comprises a polarizer, an 1/4 wave plate and a Q-switched crystal, and the polarizer, the 1/4 wave plate and the Q-switched crystal are arranged in sequence, so that irregular polarized light generated by the working substance under the excitation of the VCSEL pumping source is changed into linearly polarized light through the polarizer, the linearly polarized light is incident to the holophote through the 1/4 wave plate and the Q-switched crystal, and after being reflected by the holophote, the light passes through the Q-switched crystal and the 1/4 wave plate, and the reverse light passes through the polarizer again.

Preferably, the working substance is Nd: YAG.

Preferably, the polarizer is a thin film polarizing beam splitting prism.

Preferably, the Q-switched crystal is a Lithium Niobate (LN) crystal.

Preferably, the Q-switching module comprises a Q-switching crystal.

Preferably, the Q-switched crystal is Cr⁴⁺: YAG crystal.

The invention provides an all-solid-state laser range finder without temperature control, which can realize the all-solid-state laser range finder with stable laser output under the condition of no active temperature control.

The electro-optic Q-switched laser can stably work in the full temperature range (-40-60 ℃), and the energy is stable and can adapt to various environments. Moreover, the invention avoids the deformation of the crystal, the polarizer, the analyzer, the total reflection mirror, the output mirror and the support thereof in the cavity caused by the change of the external environment temperature, and the energy output of the laser is more stable.

Drawings

A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:

fig. 1 schematically shows a schematic structural diagram of a temperature-free temperature-controlled wide-temperature-range high-efficiency Q-switched laser for laser ranging according to a first preferred embodiment of the present invention.

Fig. 2 schematically shows a schematic structural diagram of a temperature-free temperature-controlled wide-temperature-range high-efficiency operation Q-switched laser for laser ranging according to a second preferred embodiment of the present invention.

Detailed Description

In order that the present disclosure may be more clearly and readily understood, reference will now be made in detail to the present disclosure as illustrated in the accompanying drawings.

Fig. 1 schematically shows a schematic structural diagram of a temperature-free temperature-controlled wide-temperature-range high-efficiency Q-switched laser for laser ranging according to a first preferred embodiment of the present invention.

As shown in fig. 1, the Q-switched laser for temperature-free controlled wide-temperature zone high-efficiency operation for laser ranging according to the first preferred embodiment of the present invention comprises: a control module, a power module 200, a laser module and an optical system; the control module comprises an information processor 101, a light-emitting detector 102 and a detector avalanche photodiode 103; the laser module comprises a total reflection mirror 301, a pumping module 302, a Q-switching module 303 and an output mirror 304; the control module is respectively connected with the power supply module and the laser module; the power module 200 is connected to the control module and the pumping module 302, respectively.

For example, the optical system includes a transmission optical system 401 and a reception optical system 402.

Specifically, the pump module 302 includes a working substance 3021 and a VCSEL pump source 3022, and the working substance 3021 generates randomly polarized light when excited by the VCSEL pump source 3022.

More specifically, the Q-switched module 303 includes a polarizer 3031, an 1/4 wave plate 3032 and a Q-switched crystal 3033, and the polarizer 3031, the 1/4 wave plate 3032 and the Q-switched crystal 3033 are sequentially arranged, so that the irregularly polarized light generated by the working substance 3021 under the excitation of the VCSEL pump source 3022 is incident to the all-mirror 304 through the 1/4 wave plate 3032 and the Q-switched crystal 3033 after being changed into linearly polarized light by the polarizer 3031, and after being reflected by the all-mirror 304, the inversely polarized light passes through the Q-switched crystal 3033 and the 1/4 wave plate 3032 again, and the inversely polarized light passes through the polarizer 3031.

When the voltage of the Q-switched crystal 3033 is removed instantaneously, the polarized light cannot pass through the polarizer 3031, and the purpose of generating giant pulses by switching Q is achieved by controlling the triggering of the pumping module 302 and the electro-optical switching action.

In a preferred example, for example, the working substance 3021 is Nd: YAG, the polarizer 3031 is a thin film polarization beam splitter prism, and the Q-tuning crystal 3033 is a Lithium Niobate (LN) crystal.

The laser beam output by the laser is compressed by the transmitting optical system 401 and then emitted to the detected target, meanwhile, the light-emitting detector 102 collects the laser, the laser is shaped and sent to the information processor 101, and the counter is started to time. Laser reflected by a target is converged on the detector avalanche photodiode 103 through the receiving optical system 402, an echo signal output by the avalanche photodiode 103 is amplified and shaped and then sent to the information processor 101, and the counter is closed. The information processor may calculate the distance information after completing the counting. The whole process works for 90s, has a rest for 60s, continuously works for 4 cycles, and has the light emitting frequency of 5 Hz.

Fig. 2 schematically shows a schematic structural diagram of a temperature-free temperature-controlled wide-temperature-range high-efficiency operation Q-switched laser for laser ranging according to a second preferred embodiment of the present invention.

In a second preferred embodiment of the invention, as shown in fig. 2, the Q-switching module comprises only a Q-switching crystal.

At this time, the working substance 3021 (such as Nd: YAG) generates random polarized light under the excitation of the VCSEL pump source 3022, and the laser starts pumping, and the intracavity light intensity is weak, so the Q-switched crystal 3033 (such as Cr: YAG) is passively adjusted⁴⁺: YAG crystal) has a strong absorption of the light at the wavelength of the laser, the loss in the cavity is large, the Q value is low, and the laser cannot be formed. As the pumping continues, steady state population is accumulated, the light intensity in the cavity is increased, and the Q-switched crystal 3033 (such as Cr) is passively adjusted⁴⁺: YAG crystal) is gradually bleached. Passively adjusting Q crystal 3033 (such as Cr) when the bleaching reaches a certain degree and Q value reaches a certain value⁴⁺: YAG crystal) is already on, the laser will give a strong laser pulse.

The laser beam output by the laser is compressed by the transmitting optical system 401 and then emitted to the detected target, meanwhile, the light-emitting detector 102 collects the laser, the laser is shaped and sent to the information processor 101, and the counter is started to time. Laser reflected by a target is converged on the detector avalanche photodiode 103 through the receiving optical system 402, an echo signal output by the avalanche photodiode 103 is amplified and shaped and then sent to the information processor 101, and the counter is closed. The information processor may calculate the distance information after completing the counting. The whole process works for 90s, has a rest for 60s, continuously works for 4 cycles, and has the light emitting frequency of 5 Hz.

The electro-optic Q-switched laser can stably work in the full temperature range (-40-60 ℃), and the energy is stable and can adapt to various environments. Moreover, the invention avoids the deformation of the crystal, the polarizer, the analyzer, the total reflection mirror, the output mirror and the support thereof in the cavity caused by the change of the external environment temperature, and the energy output of the laser is more stable.

It should be noted that the terms "first", "second", "third", and the like in the description are used for distinguishing various components, elements, steps, and the like in the description, and are not used for indicating a logical relationship or a sequential relationship between the various components, elements, steps, and the like, unless otherwise specified.

It is to be understood that while the present invention has been described in conjunction with the preferred embodiments thereof, it is not intended to limit the invention to those embodiments. It will be apparent to those skilled in the art from this disclosure that many changes and modifications can be made, or equivalents modified, in the embodiments of the invention without departing from the scope of the invention. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.