Dajie Huang

Multifunctional high-performance 10-J level laser system

In this letter, we report a multifunctional high-performance Nd:glass laser system. Laser pulses from an all-fiber front end are first amplified by a regenerative amplifier to 10 mJ level, and then further amplified in a four-pass amplifier. The laser system can provide 10.3-J, 3-ns laser pulses at 1053-nm wavelength. The shot-to-shot energy stability is better than 1.5% (RMS). The output laser beam is near diffraction limit. Binary amplitude masks are used to maintain a flat top near-field profile with a 71% fill factor. After the frequency conversion process, 7 and 5.5 J pulses at 526.5 and 351 nm are obtained, respectively.

Applications of OALCLV in the high power laser systems

This paper introduces the recent development of our integrated optical addressed spatial light modulator and its applications in the high power laser systems. It can be used to convert the incident beam into uniform beam for high energy effiency, or it can realize special distribution to meet the requirements of physical experiment. The optical addressing method can avoid the problem of the black matrix effect of the electric addressing device. Its transmittance for 1053nm light is about 85% and the aperture of our device has reached 22mm× 22mm. As a transmissive device, it can be inserted into the system without affecting the original optical path. The applications of the device in the three laser systems are introduced in detail in this paper. In the SGII-Up laser facility, this device demonstrates its ability to shape the output laser beam of the fundamental frequency when the output energy reaches about 2000J. Meanwhile, there’s no change in the time waveform and far field distribution. This means that it can effectively improve the capacity of the maximum output energy. In the 1J1Hz Nd-glass laser system, this device has been used to improve the uniformity of the output beam. As a result, the PV value reduces from 1.4 to 1.2, which means the beam quality has been improved effectively. In the 9th beam of SGII laser facility, the device has been used to meet the requirements of sampling the probe light. As the transmittance distribution of the laser beam can be adjusted, the sampling spot can be realized in real time. As a result, it’s easy to make the sampled spot meet the requirements of physics experiment.

An optically addressed liquid crystal light valve with high transmittance

We present an optically addressed liquid crystal light valve based on a twisted nematic liquid crystal layer associated to a photoconductive BSO layer. Based on the optical addressing of a continuous layer of liquid crystal, the spatial transmittance distribution of 1053nm coherent light through the light valve has a corresponding relationship with the intensity distribution of 470nm incoherent light projected onto the photoconductive BSO layer. This relationship has been studied experimently. As a transmissive device, it has the advantage of high transmittance and it can overcome the problem of black-matrix effect. The aperture of our device has reached 22mm× 22mm.