This paper introduces a self-tuning fuzzy temperature control system for the diode-pumped solid-state (DPSS) blue laser at 473 nm. This temperature control system includes circuit of temperature sampling, power circuit of temperature adjusting, and fuzzy proportional-integral derivative (PID) controller. Circuit of temperature sampling adopts the precision temperature sensor for exact temperature sampling. The input signal of fuzzy PID controlling is digital signal from A/D transform chip, then the input analog signal of A/D transform chip is the differential signal of temperature sampling signal and setting temperature signal. The traditional PID control method cannot self-tune parameters of Kp, Ki, Kd in operating, this paper applies the method of combining fuzzy illation with traditional PID controlling to realize self-tuning parameter of PID. This system designs the power circuit to respond to control signal of fuzzy PID controller, that power circuit is made up of high power metal-oxide-semiconductor (MOS) field effect transistors semiconductor and Peter component. This self-tuning fuzzy temperature control system has good dynamic characteristic and static characteristic, and the system has lower over-adjusting and shorter response time. The temperature control precision of system is up to +-0.05 deg., the change range of the pump laser diode wavelength is below 0.02 nm, and the power stability of the laser at 473 nm is below +-1%.
© 2007 Chinese Optics LettersPDF Article