摘要 |
PURPOSE:To reduce the value of ageing by optimizing acoustic impedance, by forming an impedance matching layer comprising a calcogenide glass film to which annealing treatment is applied to the spherical lens part of an ultrasonic condensing lens. CONSTITUTION:In an ultrasonic microscope consisting of a high frequency oscillator 1, a directional coupler 2, a transmitting receiving transducer 3, an ultrasonic condensing lens 4, a sound field medium 6, a scanning apparatus 8 and scanning circuit 9, an As-S, As-Se or As-S-Se compound is vacuum deposited to the spherical lens 4a of the ultrasonic condensing lens 4 to form a thin calcogenide glass film and annealing treatment is applied to said thin film. In this case, by changing the componential composition ratio of the thin glass film, the acoustic impedance value thereof can be arbitrarily set and, by applying said annealing treatment, the value of ageing can be reduced. |