阅读说明：本技术 脉冲周期和序列长度可控的多脉冲激光序列发生装置 (Multi-pulse laser sequence generator with controllable pulse period and sequence length ) 是由 来建成 郭嘉民 李振华 王春勇 严伟 纪运景 赵艳 于 2019-09-04 设计创作，主要内容包括：本发明公开了一种脉冲周期和序列长度可控的多脉冲激光序列发生装置,包括输出镜、色心晶体、工作介质、高功率激光二极管、可控恒流源驱动电路、干涉滤色片、快响应光电探测组件、脉冲计数电路、脉冲周期计时电路、程控控制器和上位机,该装置通过控制恒流源输出电流实现激光脉冲序列时间周期的控制,通过恒流源泵浦时间长短的调节实现激光脉冲个数的控制,利用实际激光脉冲输出个数和周期的实时监测反馈精确控制激光脉冲序列参数。本发明具有激光脉冲周期及序列长度可程控、精度高、系统工作稳定速度快、结构简单、体积小等优点,在激光探测领域具有广阔应用前景。(The invention discloses a multi-pulse laser sequence generating device with controllable pulse period and sequence length, which comprises an output mirror, a color center crystal, a working medium, a high-power laser diode, a controllable constant current source driving circuit, an interference color filter, a fast response photoelectric detection assembly, a pulse counting circuit, a pulse period timing circuit, a program-controlled controller and an upper computer. The invention has the advantages of programmable laser pulse period and sequence length, high precision, stable system operation, high speed, simple structure, small volume and the like, and has wide application prospect in the field of laser detection.)

1. A multi-pulse laser sequence generating device with controllable pulse period and sequence length is characterized by comprising an output mirror (1), a color center crystal (2), a working medium (3), a laser diode (4), a controllable constant current source driving circuit (5), an interference color filter (6), a photoelectric detection assembly (7), a pulse counting circuit (8), a pulse period timing circuit (9), a program-controlled controller (10) and an upper computer (11);

the laser diode (4), the working medium (3), the color center crystal (2) and the output mirror (1) are placed in a sealed cavity to form an end-pumped laser, the laser diode (4), the working medium (3), the color center crystal (2) and the output mirror (1) are sequentially placed in sequence, and the optical axes of all devices are ensured to be on the same straight line during installation; the controllable constant current source driving circuit (5) is connected with a laser diode (4) in the laser and provides pulse current signal output; the interference color filter (6) is embedded in an outer shell of the laser, and the interference color filter (6) is positioned behind the color center crystal (2) and in front of the output mirror (1), is positioned on the side surface of the laser shell and is not positioned on a main optical axis light path of the laser; the photoelectric detector assembly (7) is arranged on the optical axis of the interference color filter (6) and is respectively connected with the pulse counting circuit (8) and the pulse period timing circuit (9); the pulse counting circuit (8) and the pulse period timing circuit (9) are simultaneously connected to the program-controlled controller (10); the program-controlled controller (10) is connected with an upper computer (11); the upper computer (11) is connected with the controllable constant current source driving circuit (5).

2. The multi-pulse laser sequence generator with controllable pulse period and sequence length according to claim 1, wherein the controllable constant current source driving circuit (5) is used for outputting pulse current, and the current magnitude and duration are adjustable.

3. A multi-pulse laser train generating device with controllable pulse period and train length according to claim 1, characterized in that the interference filter (6) has a center wavelength of 1535nm and a bandwidth of 10 nm.

4. A multi-pulse laser train generating device with controllable pulse period and train length according to claim 1, characterized in that the laser diode (4) has a center wavelength of 940 nm.

5. The multi-pulse laser sequence generator with controllable pulse period and sequence length according to claim 1, wherein the laser diode (4), the working medium (3), the color center crystal (2) and the output mirror (1) form an LD end-pumped laser, which emits a laser signal with a center wavelength of 1535nm, a bandwidth of 10nm, and an emission angle range of 1-1.5 milliradians.

6. The multi-pulse laser train generating apparatus of claim 1, wherein the response time of the photodetector assembly is 0.5 ns.

Technical Field

The invention relates to a pulse laser sequence generation technology, in particular to a multi-pulse laser sequence generation device with controllable pulse period and sequence length.

Background

With the rapid development of laser generating devices, laser radars have gradually been widely used in the fields of civilian use, military use, scientific research and the like due to the advantages of high resolution, strong anti-interference capability, excellent low-altitude detection capability, small volume, light weight and the like. The demand of laser radar for laser signal generating devices is increasing.

In the conventional laser signal generating device, the laser signal which can be generated by the conventional laser signal generating device is determined by the driving circuit and the laser together, and only a specific laser signal or several laser signals can be generated. The invention patent with the patent publication number of CN 169861070A discloses a laser generating device, which comprises a laser, an acousto-optic crystal, a collimating mirror and a selective diaphragm, and can simultaneously realize synchronous mode-locking dual-wavelength picosecond pulse output and dual-wavelength asynchronous femtosecond pulse output, but only can output ultrashort pulse laser, and the output laser period is not adjustable.

In a specific laser radar use process, in order to meet more complex measurement environments and requirements, the laser radar needs to be capable of generating a plurality of different laser sequences, and under the application environment, a laser sequence generating device which can only output one or more fixed periods cannot meet the requirements.

Disclosure of Invention

The invention aims to provide a multi-pulse laser sequence generating device with controllable pulse period and sequence length.

The technical scheme for realizing the purpose of the invention is as follows: a multi-pulse laser sequence generating device with controllable pulse period and sequence length comprises an output mirror, a color center crystal, a working medium, a laser diode, a controllable constant current source driving circuit, an interference color filter, a photoelectric detection assembly, a pulse counting circuit, a pulse period timing circuit, a program-controlled controller and an upper computer;

the laser diode, the working medium, the color center crystal and the output mirror are arranged in a sealed cavity to form an end-pumped laser, the laser diode, the working medium, the color center crystal and the output mirror are sequentially arranged in sequence, and the optical axes of all devices are ensured to be on the same straight line during installation; the controllable constant current source driving circuit is connected with a laser diode in the laser and provides pulse current signal output; the interference color filter is embedded in an outer shell of the laser, is positioned behind the color center crystal and in front of the output mirror, is positioned on the side surface of the laser shell and is not positioned on a main optical axis light path of the laser; the photoelectric detector assembly is arranged on the optical axis of the interference color filter and is respectively connected with the pulse counting circuit and the pulse period timing circuit; the pulse counting circuit and the pulse period timing circuit are simultaneously connected to the program-controlled controller; the program-controlled controller is connected with the upper computer; the upper computer is connected with the controllable constant current source driving circuit.

Compared with the prior art, the invention has the following remarkable advantages: (1) the laser uses an LD end face pump laser, and a novel laser diode clinging type pump structure is adopted in the laser, and the structure utilizes the near field characteristic of the laser diode, so that the volume of the laser is further reduced on the premise of ensuring output, and the whole device can be further miniaturized; (2) the feedback circuit is added on the basis of the traditional multi-pulse laser sequence generating device, and can firstly complete the work similar to that of a laser detector, namely, the detection function of the signal generated by the generating device is completed, so that a user can obtain the data of the laser signal in real time; meanwhile, the feedback circuit can control the laser driving circuit by utilizing the program-controlled controller so as to change important parameters such as the pulse number, the pulse width, the duty ratio and the like of the generated laser signals, so that the signal generating task of the laser radar under various complex conditions can be completed.

Drawings

FIG. 1 is a schematic diagram of a multi-pulse laser sequence generator with controllable pulse period and sequence length according to the present invention.

FIG. 2 is a schematic diagram of a single-pulse laser period feedback control process according to the present invention.

Detailed Description

As shown in fig. 1, a multi-pulse laser sequence generator with controllable pulse period and sequence length comprises an output mirror 1, a color center crystal 2, a working medium 3, a laser diode 4, a controllable constant current source driving circuit 5, an interference color filter 6, a photoelectric detection component 7, a pulse counting circuit 8, a pulse period timing circuit 9, a program-controlled controller 10 and an upper computer 11;

the laser diode 4, the working medium 3, the color center crystal 2 and the output mirror 1 are placed in a sealed cavity to form an end-pumped laser, the elements are placed in sequence of the laser diode 4, the working medium 3, the color center crystal 2 and the output mirror 1, and the optical axes of all the devices are ensured to be on the same straight line during installation; the controllable constant current source driving circuit 5 is connected with a laser diode 4 in the laser and provides pulse current signal output; the interference color filter 6 is embedded in an outer shell of the laser, and the interference color filter 6 is positioned behind the color center crystal 2 and in front of the output mirror 1, is positioned on the side surface of the laser shell and is not positioned on a main optical axis light path of the laser; the photoelectric detector component 7 is arranged on the optical axis of the interference color filter 6 and is respectively connected with the pulse counting circuit 8 and the pulse period timing circuit 9; the pulse counting circuit 8 and the pulse period timing circuit 9 are simultaneously connected to the program-controlled controller 10; the program-controlled controller 10 is connected with an upper computer 11; the upper computer 11 is connected with the controllable constant current source driving circuit 5.

Further, the controllable constant current source driving circuit 5 is used for outputting stable pulse current, and the current magnitude and duration are adjustable.

Furthermore, the central wavelength of the interference filter 6 is 1535nm, the bandwidth is 10nm, and the transmittance to laser light of 1535nm is high, so that stray light generated in a laser can be filtered, and a laser signal of 1535nm wave band can enter the photoelectric detector assembly.

The program-controlled controller 10 adopts a control method of series current circulation feedback, and has the advantages of fast dynamic response, small dynamic error and good output stability.

Furthermore, the laser diode 4, the working medium 3, the color center crystal 2 and the output mirror 1 form an LD end-pumped laser, which can emit a laser signal with a center wavelength of 1535nm, the bandwidth is 10nm, and the emission angle range is 1-1.5 milliradians.

Further, the response time of the fast response photodetector assembly 7 is 0.5ns, and the fast response photodetector assembly is used for detecting a laser signal with a pulse width of ns magnitude generated by a laser device.

The device generates a current signal by a power supply and inputs the current signal into a controllable constant current source driving circuit 5, and then the controllable constant current source driving circuit 5 modulates the current signal and then accesses a laser diode 4 to generate pump light. The pump light enters a resonant cavity formed by the working medium 3, the color center crystal 2 and the output mirror 1 to generate a laser signal. An interference color filter 6 in the device selects stray light generated by a laser pump, laser signals with a wave band of 1535nm are screened through the interference color filter 6, the laser signals selected through the interference color filter 6 enter a photoelectric detector 7 to generate electric signals, the electric signals are input into a pulse counting circuit 8 and a pulse period timing circuit 9, feedback signals are generated according to a preset feedback control program in a program control controller 10, the generated feedback signals are output into an upper computer 11, finally, the upper computer 11 sends control commands to a controllable constant current source driving circuit 5 to change parameters such as pulse number, pulse width and frequency of the controllable constant current source driving circuit, and finally, adjustment of key parameters such as the duty ratio of the laser signals emitted by the laser is completed.

The technical solution of the present invention will be described in detail with reference to examples.