LOW NOISE-PULSE SOLID-STATE SHG LASER

• Main Authors: SATO MASAZUMI, MAKIO SATOSHI, ISHIDA HIDENOBU
• Format: Patent
• Language: English
• Published: 31.08.1999
• Edition: 6
• Subjects: BASIC ELECTRIC ELEMENTS; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; DEVICES USING STIMULATED EMISSION; ELECTRICITY; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

PROBLEM TO BE SOLVED: To obtain stable laser pulses, which do not include mode competitive noises, by shortening the current driving period of a laser semiconductor than the period, wherein the minimum value between the first peak and the second peak of the alleviating vibration of the laser output determined by a laser resonator and a solid-state laser medium is reached. SOLUTION: The constitution of an optical system uses a laser crystal 7 using a single crystal of Cr:LiSrAlF6 as a solid-state laser medium, a single crystal 9 of LiB3 O5 of the second higher-harmonic wave generating medium and a red semiconductor laser 4 as an exciting light source. Excited light 11 emitted from a semiconductor laser 4 is condensed at the laser crystal 7. An optical resonator is formed between a laser mirror 6 and one-end surface of the single crystal 9, and takes out second higher-harmonic waves 13 efficiently. One condition of the prevention of noise generation is to make the continuing time of the rectangular pulse of the driving current to be supplied to the semiconductor laser of the exciting source shorter than the time reaching the minimum value present between the first and second peaks in the alleviation- vibrating pulse lines.