Abstract: The invention is based on the problem of providing an inspection device and an inspection method, which recognise the defective lenses, which are difficult to detect with conventional optical methods, with a high degree of reliability. According to the invention, the contact lenses are exposed to an ultrasonic field, which leads to destruction of defective lenses, while perfect lenses are as a rule not destroyed. In particular, the method is capable of detecting cracks which are often overlooked by optical methods, since this type of defect reacts especially sensitively to the soundwaves being received.

Abstract: The invention is based on the problem of providing an inspection device and an inspection method, which recognise the defective lenses, which are difficult to detect with conventional optical methods, with a high degree of reliability. According to the invention, the contact lenses are exposed to an ultrasonic field, which leads to destruction of defective lenses, while perfect lenses are as a rule not destroyed. In particular, the method is capable of detecting cracks which are often overlooked by optical methods, since this type of defect reacts especially sensitively to the soundwaves being received.

Abstract: A method and device for determining surface structure and subsurface structures wherein the article to be examined is placed upon a support surface and through a liquid or solid medium ultrasonic waves are directed at the surface and backscattered waves are received and processed. The frequency of the ultrasonic waves is selected to provide information of the subsurface structure to a depth of substantially one wavelength.