| 摘要 |
PURPOSE:To display the correlation signal between an elastic wave propagating on the surface and an image which is projected to the surface, easily with high sensitivity, by providing a CdS-CdSe photoconductive film on a piezoelectric substrate. CONSTITUTION:The surface of what is called a Y plate of a piezoelectric material crystal is polished to a specular face to attain a substrate 2. The inside of a crucible 1 is heated to a temperature of 8-9X10<2> deg.C to form a CdS-CdSe film having a thickness of about 500Angstrom for 15 minutes. An attained vapor-deposition film 3 is liver-colored and has a very high electric resistance, and this film 3 is subjected to heat treatment. A reactive agent is made fine pulverous in a closed vessel to make the heat treatment possible. When the surface elastic wave signal of center frequency 62MHz is propagated on the surface of the substrate 2, the electric field due to the propagated signal induces a nonlinear effect in the vapor-deposition film 3 to induce higher harmonic components of 124MHz, and a correlation signal, which corresponds to the intensity of light projected onto the vapor-deposition film 3, of the signal indicating center frequency components of 124MHz is outputted. Thus, the correlation signal between elastic wave propagated on the surface and the image projected to the surface is attained. |
