Specialist in Special Optical Devices

Fiber Laser Applicaton

Fiber Laser Applicaton

System Introduction

High Power Picosecond Laser has been widely used in the fields of Precision Processing of Material , LED Chip Dicing, OLED Cutting, Solar Photovoltaic and other scientific research with high peak power and narrow pulse width (PS Grade). Compared with Nanosecond Pulse Laser and Picosecond Laser, it has many advantages, such as high machining accuracy, low thermal effect and no cutting burr on the machining edge. Compared with the Femtosecond Pulse Laser, it has a simple structure and high cost performance because it does not need to expand and compress the pulse for amplification.

For industrial processing, the single pulse energy is required to be in μ J level, while picosecond seed source is usually in MHz level, and the single pulse energy is in NJ level. In order to obtain high single pulse energy, the seed source is usually first reduced frequency, and then the high single pulse energy output is reached by Free Space amplifier.

Working Principle

The high power Picosecond Laser usually consists of three parts: picosecond seed source, menu, and optical amplifier. Generally, the picosecond seed source is SESAM picosecond fiber seed source laser, Fiber Coupled Acousto-Optic Modulator (AOM), Free Space Faraday Rotator ( Faraday Isolator), and primary or multistage amplifier.

There are three kinds of high gain amplifiers: Fiber Optical Amplifier, Regenerative Amplifier and Multi Pass Traveling Wave Amplifier. The advantages of fiber optical amplifier are high output power, high gain, simple structure, but it is affected by the nonlinear effect of fiber, so it can not obtain high single pulse energy, usually less than 10 μ J. The advantages of regenerative amplifier are high gain, easy to obtain more than 200 μ J pulse energy, but the disadvantages are the complex structure of the amplifier cavity, very high requirements for pulse sequence, high requirements for electronic control, high cost, and low stability. At present, the Multi Pass Traveling Wave Amplifier is one of the most widely used amplification solutions in the industrial market. It is simple in structure, stable and reliable, low cost, and easy to obtain high pulse energy. However, because the gain of single-stage amplifier is not high, it needs multi-stage amplification to obtain the required gain.

System Structure

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Optical Components List

NOITEMFUNCTION

1

Picosecond Optical Fiber Seed Source Laser

Picosecond Optical Fiber Seed Source(1064,¡Ü40Mhz,nJ)

2

Fiber Coupled Acousto-Optic Modulator (AOM)

To select the seed source (frequency reduction) and reach 1MHz, NJ

3

FC/APC(SMA) Fix Focus Collimator

To reach FC / APC (SMA) connector free space collimation output

4

Free Space Acousto-Optic Modulator (AOM)

Single frequency reduction again for signal light to 100-1000khz, NJ

5

Faraday Rotator (Faraday Isolator)

The linear polarized light is rotated 45 ¡ã by Faraday Rotator, and a polarizer or Glan-Taylor is added to form the Isolator to ensure the single direction light transmission and prevent the reflected light from returning to the light path and affecting the stability of the system.