CN214673438U

CN214673438U - Gain switch type pulse laser amplifier

Info

Publication number: CN214673438U
Application number: CN202120678572.0U
Authority: CN
Inventors: 丁广雷; 卢登连; 黄兴端; 鲍日焰; 朱守糥; 张哨峰
Original assignee: Fujian Haichuang Photoelectric Co ltd
Current assignee: Fujian Haichuang Photoelectric Technology Co.,Ltd.
Priority date: 2021-04-02
Filing date: 2021-04-02
Publication date: 2021-11-09
Anticipated expiration: 2031-04-02

Abstract

The utility model relates to a gain switch type pulse laser amplifier, which comprises a continuous seed light source, an isolator, a gain medium, a beam combiner, a pumping light source and a modulator; the seed light emitted by the continuous seed light source is coupled into the gain medium after passing through the isolator; the pump light source outputs pulse pump light after being modulated by the modulator, and the pulse pump light is coupled to the gain medium after passing through the beam combiner. The utility model discloses an use the gain switch technique, become amplified pulse laser output to continuous output's seed light, effectively reduced ASE to required pulse shape output has been kept.

Description

Gain switch type pulse laser amplifier

Technical Field

The utility model relates to a laser radar field, concretely relates to gain switch formula pulse laser amplifier.

Background

The emitting source applied to laser radar is usually a pulse laser amplifier, and the common pulse laser amplifier adopts a pulse seed light source and an amplifier structure of continuous optical pumping. The problem of the common pulse laser is that the ASE is relatively large, continuous pump light forms inversion particle numbers in a pumping mode all the time in a time period without seed light pulses, the inversion particle numbers are easy to form the output of the ASE because no seed light pulses are consumed, the signal-to-noise ratio of output laser is reduced, and the detection performance of the laser radar is reduced. In addition, the waveform of the common pulse laser is deformed in the amplification process, and the waveform of a transmitting source required by the laser radar is not easy to control.

Disclosure of Invention

It is therefore an object of the present invention to provide a gain-switched pulse laser amplifier to reduce ASE and maintain a desired pulse shape output.

In order to realize the purpose, the utility model adopts the following technical scheme:

a gain switch type pulse laser amplifier comprises a continuous seed light source, an isolator, a gain medium, a beam combiner, a pumping light source and a modulator; the seed light emitted by the continuous seed light source is coupled into the gain medium after passing through the isolator; the pump light source outputs pulse pump light after being modulated by the modulator, and the pulse pump light is coupled to the gain medium after passing through the beam combiner; the gain medium forms population inversion during the period of pulse pump light to amplify the seed light, and only absorbs the seed light without amplification during the period of no pulse pump light.

Further, the continuous seed light source adopts a semiconductor laser, a solid laser or a fiber laser.

Further, the continuous seed light source wavelength includes a wavelength band from ultraviolet light to infrared light.

Further, the gain medium is made of crystal, glass, optical fiber or semiconductor.

Further, the pump light source is a semiconductor laser, a solid laser or a fiber laser.

Compared with the prior art, the utility model following beneficial effect has:

the utility model discloses an use the gain switch technique, become the seed light of continuous output into the pulse laser output of enlargeing. ASE is reduced and the desired pulse shape output is maintained.

Drawings

FIG. 1 is a schematic diagram of a gain switched pulse laser amplifier according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the pump pulses of the gain switched pulse laser amplifier of the present invention;

the device comprises a 1-continuous seed light source, a 2-isolator, a 3-gain medium, a 4-beam combiner, a 5-pumping source and a 6-modulator.

Detailed Description

The present invention will be further explained with reference to the drawings and the embodiments.

Referring to fig. 1, the present embodiment provides a gain switch type pulse laser amplifier, which includes a continuous seed light source 1, an isolator 2, a gain medium 3, a beam combiner 4, a pump light source 5, and a modulator 6;

in this embodiment, the continuous light source 1 is a continuous output semiconductor laser, and the seed light emitted by the continuous light source is coupled into the gain fiber 3 through the isolator 2, and the pump source 5 outputs a pulse pump light after being modulated by the modulator 6, and is coupled into the gain fiber 3 through the beam combiner 4 to pump the gain fiber 3. The gain medium forms population inversion during the period of pulse pump light to amplify the seed light, and only absorbs the seed light without amplification during the period of no pulse pump light.

In this embodiment, as shown in fig. 2, 0 to t1, t2 to t3, and t4 to t5, in a time period in which the pump pulse light is present, the gain fiber 3 forms population inversion, and the seed light passing through the gain fiber 3 is amplified and output after passing through the beam combiner 4.

As shown in t 1-t 2 and t 3-t 4 of FIG. 2, in the time period without pulse light, since the absorption coefficient of the gain fiber 3 for the seed light is very high, the seed light is almost completely absorbed after passing through the gain medium, and therefore, no seed light is output in the time period without pulse light. Thereby obtaining an amplified laser pulse output, the output laser pulse being highly correlated with the modulator electrical pulse signal. Laser pulse output such as square wave, sine wave or triangular wave can be obtained by changing the waveform of the electric pulse of the pump light source modulator; changing the amplitude and duty cycle of the modulator drive current changes the intensity and pulse width of the output laser pulses; varying the repetition rate of the modulator allows the repetition rate of the output laser pulses to be continuously adjustable.

The above is only the preferred embodiment of the present invention, and all the equivalent changes and modifications made according to the claims of the present invention should be covered by the present invention.

Claims

1. A gain switch type pulse laser amplifier is characterized by comprising a continuous seed light source, an isolator, a gain medium, a beam combiner, a pumping light source and a modulator; the seed light emitted by the continuous seed light source is coupled into the gain medium after passing through the isolator; the pump light source outputs pulse pump light after being modulated by the modulator, and the pulse pump light is coupled to the gain medium after passing through the beam combiner; the gain medium forms population inversion during the period of pulse pump light to amplify the seed light, and only absorbs the seed light without amplification during the period of no pulse pump light.

2. A gain switched pulse laser amplifier as claimed in claim 1, wherein said continuous seed light source is a semiconductor laser, a solid state laser or a fiber laser.

3. A gain switched pulsed laser amplifier as defined in claim 1 wherein said continuous seed source wavelength comprises the ultraviolet to infrared wavelength band.

4. A gain switched pulse laser amplifier as claimed in claim 1, wherein said gain medium is crystal, glass, fiber or semiconductor.

5. A gain switched pulse laser amplifier as claimed in claim 1 wherein said pump light source is a semiconductor laser, a solid state laser or a fiber laser.