THIN-FILM OPTICAL ELEMENT AS WELL AS OPTICAL CONTROL METHOD AND OPTICAL CONTROLLER USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide such a thin-film optical element which exhibits optical response of sufficient magnitude and speed by using a laser beam of low power as control light, an optical control method and an optical controller. ;SOLUTION: The control light is emitted from a light source 1 and signal light from a light source 2. The control light and the signal light are converted by a condenser lens 7 and is cast to the thin-film optical element 8. Only the signal light is detected by a photodetector 22 through a light receiving lens 9 and a wavelength selecting filter 20. A heat lens is reversibly formed within the thin-film optical element by on and off of the control light and the intensity modulation of the signal light is embodied. The constitution of the thin-film optical element 8 comprises the laminated structure consisting of, for example, a heat transfer layer film/heat insulating layer film/light absorption layer film/ heat insulating layer film/heat transfer layer film. The obtaining of the optical response of the sufficient magnitude and speed by using the laser beam of the low power as the control light is made possible by adjusting the thickness of the light absorption layer film so as not to exceed twice the confocal length of the converged control light.;COPYRIGHT: (C)1999,JPO