Patent ID: 8976203
Filing Date: 2015-03-10
Classification: G03B,H01S,H04N

Abstract:
1. A wavelength conversion device, comprising: an excitation light source that generates excitation light; a laser medium that generates fundamental light by means of the excitation light; two resonator mirrors that are disposed with the laser medium being interposed therebetween and resonate the fundamental light; a wavelength conversion element that is disposed between the two resonator mirrors and wavelength-converts the fundamental light to harmonic light; and a drive unit that generates a pulse modulation signal to pulse-drive the excitation light source, wherein the laser medium is formed of a material having a thermo-optical effect and a positive thermo-optical constant, the pulse modulation signal generated by the drive unit has an initial interval including a rising edge of a pulse and a remaining interval subsequent to the initial interval, an average signal intensity during the initial interval is higher than an average signal intensity during the remaining interval, and when a degree of parallelism between the two resonator mirrors is θ (arc-minute) and an energy of the pulse modulation signal during the initial interval is E (joule), the drive unit generates the pulse modulation signal which satisfies: