| 摘要 |
PURPOSE: To provide a window having an ultrasonic device which can be applied even to an asymmetric windshield. CONSTITUTION: This window includes at least a first and a second sheets 16, 18 integrally combined by a coupling layer 20, and an ultrasonic device 12 disposed between these sheets 16, 18 to directly cooperate with a first sheet 24 of the first sheet 16 for detecting existence of foreign matter on a second surface 26 on the opposite side of the first surface 24 of the first sheet 16 is provided. The ultrasonic device 12 has a transducer 28 to generate an incidental ultrasonic signal of a wavelengthλon the first sheet 16 of a thickness of k.λ/2, where k is an integer, through a transmitting/receiving surface. |
