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Qingdao, China

Xia J.,Shandong University | Liu Z.,Shandong University | Zhang S.,Shandong University | Qiu G.,Qingdao Lasence Co.
Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering

Temperature was one of the parameters influencing the characteristic of the semiconductor laser. To realize the temperature control quickly and stably,the temperature controlling hardware and algorithm were researched. The system was based on the Micro Control Unit (MCU) MSP430. The driver circuit was used, adjusting circuit voltage adaptively was in conjunction with output style of pulse width modulation. The self-adjusting temperature algorithm was also designed by the model of the mechanical temperature balance and experiment in high-low temperature test-box. According to the experiment result, the stability time from the temperature -40-h 50℃ to the setting temperature 23℃ were respectively 2 min 30 s and l min 30 s, respectively. The control precise was 0.2℃. By the analysis of power stability experiment result, the laser power stability is improved from 5% before temperature control to less than 1% after temperature control. The laser power stability density is safe for the eye. The schematic design of system has significance for the small power and quick stability laser system. ©, 2015, Chinese Society of Astronautics. All right reserved. Source

Han X.-K.,Qingdao Lasence Co. | Guo E.-X.,Qingdao Municipal Hospital Group | Yu X.-S.,Qingdao Lasence Co. | Qiu G.,Qingdao Lasence Co.
Rengong Jingti Xuebao/Journal of Synthetic Crystals

For the demand on the small power green laser of 545 nm used in the dental treatments, a small power and efficient green laser was developed based on the Nd: GdCOB crystal. A high optical quality Nd: GdCOB crystal was grown by the Czochralski method. A microchip structure was used for the laser, and the pump source was a 300 mW laser-diode. By optimizing the 8at% Nd: GdCOB self-frequency doubled (SFD) laser medium, we obtained a 23 mW SFD laser at 545 nm, with the threshold only 40 mW. The laser device was about 1 cm in length, with several advantages in the weight, carriage, miniature and compact structure, which determines that it has potential in the dental treatments. ©, 2014, Chinese Ceramic Society. All right reserved. Source

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