Abstract:
The invention offers a low-noise, compact, high-efficiency light generating device and an irradiation method thereof for use in medical applications. A fundamental harmonic laser head 106 is composed of a quasi-continuous wave oscillation mode laser diode (QCW-LD) 101, a laser crystal 103, a rear mirror 104 and an output mirror 105. The QCW-LD 101 is driven by an LD power source 102 capable of modulating the pulse waveform in time. A beam adjusting portion 108 comprises a wave plate, a polarizer, a lens and an isolator. A wavelength converting portion 112 is an optical parametric oscillator (OPO) comprising a non-linear optical crystal 109, an OPO input mirror and an OPO output mirror 111.