FREQUENCY UPWARD CONVERSION SOLID-STATE LASER DEVICE

• Main Authors: NAKATSUKA MASAHIRO, NAITO KENTA, MASAKO SACHIKO, YAMANAKA MASANORI, KUWANO YASUHIKO, NAKAI SADAO, SAITO SEIICHI
• Format: Patent
• Language: English
• Published: 25.04.1995
• 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

PURPOSE:To obtain a frequency upward conversion solid-state laser device which is variable in a wavelength range of 400nm to 515nm. CONSTITUTION:A semiconductor laser 1 of wavelength band 800nm is used as an excitation optical source concerned with laser oscillation, and excitation light is made to irradiate an Er:YVO4 laser chip 3 by a condensing lens 2. At this point, the optical axis of the semiconductor laser 1 and the crystal axis of the Er:YVO4 laser chip 3 are so set as to be put in a positional relation of o polarization, pi polarization between them. The Er:YVO4 laser chip 3 is coated with a high reflection mirror coating 4 and an anti-reflection coating 5 correspondent to light ray of wavelength band 400 to 515nm which a solid- state laser is capable of oscillating and an anti-reflection coating 6 correspondent to the oscillation wavelength 800nm of the semiconductor laser 1, and the laser chip 3 and an output coupling mirror 7 are combined together to constitute a resonator structure. A concave lens 7 is used as the output coupling mirror 7 so as to make output laser ray collimated.