High-speed pulse string laser generating device

Abstract

The utility model discloses a high-speed pulse string laser generating device which comprises a laser seed source, a pulse beam splitter, a laser amplifier and a light beam combiner. The laser seed source is used for generating a pulse light signal; the pulse beam splitter is used for receiving the pulse light signal generated by the laser seed source so as to distribute power to the pulse light signal according to a certain proportion and can control the time delay of the pulse light signal; the laser amplifier is used for receiving the pulse optical signal output by the pulse beam splitter and amplifying the low-power pulse optical signal; and the light beam combiner is used for combining the pulse light signals output by the laser amplifier.

Description

Technical Field

[0001] The utility model relates to the technical field of optical equipment manufacturing, in particular to a device for generating high-speed pulse train lasers. Background Art

[0002] For pulse laser material precision processing, increasing the pulse repetition frequency, shortening the interval between pulses and using pulse train processing methods have important application value. First, the pulse train can reduce heat diffusion, avoid the diffusion of heat from a single large energy pulse to the area around the processing point, form a large heat-affected zone, and reduce processing accuracy and quality; secondly, high repetition frequency can reduce energy loss during pulse superposition, use residual heat to continuously increase the temperature of the processing position, and increase processing speed; in addition, high repetition rate pulse lasers will also form effects such as "ablation cooling" during the interaction with materials, further improving processing efficiency and quality. The processing effect can be further optimized by accurately allocating the energy of each pulse in the pulse train. The currently commonly used electrical modulation technology solution is limited by the system bandwidth and it is difficult to output too high a repetition rate. Although the newly developed GHz-level high repetition rate seed source can reduce the pulse interval time, the intensity of each pulse cannot be accurately set. Utility Model Content

[0003] The purpose of the utility model is to provide a device and method for generating a high-speed pulse train laser, so as to solve one or more technical problems existing in the prior art, and at least provide a beneficial choice or create conditions.

[0004] The utility model adopts the following technical solutions to achieve the above utility model objectives:

[0005] The utility model provides a device for generating high-speed pulse train laser, comprising a laser seed source, a pulse beam splitter, a laser amplifier and a photosynthetic beam combiner;

[0006] The laser seed source is used to generate a pulse light signal;

[0007] The pulse beam splitter is used to receive the pulse light signal generated by the laser seed source, so as to distribute the power of the pulse light signal according to a certain ratio and control the time delay of the pulse light signal;

[0008] The laser amplifier is used to receive the pulse light signal output by the pulse beam splitter and amplify the low-power pulse light signal;

[0009] The optical beam combiner is used to combine the pulse light signals output by the laser amplifier.

[0010] Furthermore, the pulse light signal generated by the laser seed source has a repetition frequency of less than 200 MHz and a pulse width ranging from 5 nanoseconds to 500 femtoseconds.

[0011] Further, the pulse beam splitter includes at least one group of couplers, and the number of couplers in each group is set to two;

[0012] The input end of each set of couplers is respectively connected to the laser seed source, and the output end is respectively connected to the input end of another set of couplers, so as to obtain two laser signals of equal power.

[0013] Furthermore, when 2 n When the laser output is equal in power, 2 n -1 set of couplers, n is a positive integer.

[0014] Furthermore, the pulse beam splitter controls the arrival time of the pulse light signal by cutting and extending the optical fiber.

[0015] Furthermore, the laser amplifier amplifies the multi-path pulse optical signals generated by the pulse beam splitter at the same magnification or at different magnifications.

[0016] Further, the laser amplifier includes a pump laser source, a pump beam combiner, a gain optical fiber and an inter-stage isolator;

[0017] The energy of the pump laser source enters the gain optical fiber through the pump beam combiner to amplify the energy of the low-power front-stage signal.

[0018] Furthermore, the optical combiner combines multiple amplified pulse optical signals into a single optical fiber for output.

[0019] The beneficial effects of the utility model are as follows:

[0020] The utility model realizes a pulse train processing, in which the sub-pulse interval in the pulse train is determined by optical fiber delay, thereby providing a very small sub-pulse interval;

[0021] Because independent amplifiers are used, the energy of each sub-pulse can be precisely controlled, rather than being limited by the energy storage status and energy extraction rate in a single amplifier. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A logic block diagram of a high-speed pulse train laser generating device provided according to an embodiment of the utility model;

[0023] Figure 2 This is a waveform diagram obtained by combining beams through a beam combiner in a high-speed pulse train laser generating device provided according to an embodiment of the utility model.

[0024] In the figure: 10, fiber laser; 20, pulse beam splitter; 30, laser amplifier; 40, photosynthetic beam combiner. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0026] like Figure 1 A device for generating a high-speed pulse train laser is shown, comprising a laser seed source 10, a pulse beam splitter 20, a laser amplifier 30 and an optical beam combiner 40; the laser seed source 10 is used to generate a pulse light signal; the pulse beam splitter 20 is used to receive the pulse light signal generated by the laser seed source 10, and control the time delay of the pulse light signal by cutting off and extending the optical fiber length; the laser amplifier 30 is used to receive the pulse light signal output by the pulse beam splitter 20 and amplify the pulse light signal; the optical beam combiner 40 is used to combine the pulse light signals output by the laser amplifier 30 to obtain a Figure 2 The waveform shown, when processing materials with smooth surfaces, such as wafers and glass, the higher energy P1 and P2 first destroy the roughness of the workpiece surface, thereby reducing light reflection and increasing laser absorption. When the surface is no longer smooth, P3 and P4 can be processed with lower energy (because of higher absorption), thus ensuring a better processing section. The larger interval between P2 and P3 ensures the dissipation of high heat in the front and avoids thermal effects. P1 is lower than P2 for better edge collapse control.

[0027] Based on the above structure, the laser seed source 10 generates a high-quality, high-signal-to-noise ratio pulse light signal with a repetition frequency of less than 200 MHz and a pulse width ranging from 5 nanoseconds to 500 femtoseconds.

[0028] Based on the above structure, the pulse beam splitter 20 includes at least one group of couplers, and the number of couplers in each group is set to two; wherein the input end of each group of couplers is respectively connected to the laser seed source 10, and the output end is respectively connected to the input end of another group of couplers, so as to obtain two pulse optical signals of equal power.

[0029] Based on the above structure, the pulse beam splitter 20 is composed of the above series topological structure. When 2 n When the laser output is equal in power, 2 n -1 set of couplers, n is a positive integer.

[0030] Based on the above structure, the length of the optical fiber of the pulse beam splitter 20 needs to be accurately cut to adjust the delay of the laser pulse. According to the refractive index, a 0.2-meter-long optical fiber corresponds to approximately a 1-nanosecond optical pulse delay. By cutting and extending the optical fiber, the arrival time of the optical pulse can be accurately controlled.

[0031] Based on the above structure, the laser amplifier 30 amplifies the energy of each pulse light signal, which can be equal or different magnifications. The laser amplifier 30 is composed of a cascaded multi-stage amplification structure. The laser amplifier 30 includes a pump laser source, a pump combiner, a gain fiber and an inter-stage isolator. The energy of the pump laser source enters the gain fiber through the pump combiner to amplify the energy of the low-power front-stage signal.

[0032] Based on the above structure, the optical combiner 40 combines the multiple amplified pulse optical signals into a single optical fiber for output.

[0033] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A device for generating a high-speed pulse train laser, characterized in that: Including laser seed source, pulse beam splitter, laser amplifier and photosynthesizer; The laser seed source is used to generate a pulse light signal; The pulse beam splitter is used to receive the pulse light signal generated by the laser seed source, so as to distribute the power of the pulse light signal according to a certain ratio and control the time delay of the pulse light signal; The laser amplifier is used to receive the pulse light signal output by the pulse beam splitter and amplify the low-power pulse light signal; The optical beam combiner is used to combine the pulse light signals output by the laser amplifier; The pulse light signal generated by the laser seed source has a repetition frequency of less than 200 MHz and a pulse width ranging from 5 nanoseconds to 500 femtoseconds; The pulse beam splitter controls the arrival time of the pulse light signal by cutting and extending the optical fiber.

2. The device for generating a high-speed pulse train laser according to claim 1, characterized in that: The pulse beam splitter includes at least one set of couplers, and the number of couplers in each set is set to two; The input end of each set of couplers is respectively connected to the laser seed source, and the output end is respectively connected to the input end of another set of couplers, so as to obtain two laser signals of equal power.

3. The device for generating a high-speed pulse train laser according to claim 2, characterized in that: When you get 2 n When the laser output is equal in power, 2 n -1 set of couplers, n is a positive integer.

4. The device for generating a high-speed pulse train laser according to claim 1, characterized in that: The laser amplifier amplifies the multi-path pulse optical signals generated by the pulse beam splitter at the same magnification or at different magnifications.

5. The device for generating a high-speed pulse train laser according to claim 1, characterized in that: The laser amplifier comprises a pump laser source, a pump beam combiner, a gain optical fiber and an inter-stage isolator; The energy of the pump laser source enters the gain optical fiber through the pump beam combiner to amplify the energy of the low-power front-stage signal.

6. The device for generating a high-speed pulse train laser according to claim 1, characterized in that: The optical combiner combines multiple amplified pulse optical signals into a single optical fiber for output.

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