Ultrasound camera

摘要

Sound can be processed "optically" as light. A generated sound picture (image) is converted into electrical signals with a selective pressure-sensitive sensor field, which signals are processed to obtain a video picture. To prevent sound disturbances from outside, the frequencies which deviate from the transmitting frequency are filtered out. To obtain a high picture quality, high-frequency ultrasound is used as far as possible. The sound signals are reflected by the object in varying intensity depending on material and surface condition. The sensor consists of small piezoelectrical elements (grid size in the range of tenths of mm to 1 mu m). Applications. Working in muddy waters. In the case of very high sound intensities, also in marine research for relatively large areas and depths. Field of medicine: for "transilluminating" body parts; as aid for examinations (conventional devices do not have the high resolution). When using different frequencies simultaneously, it is possible to produce "colour pictures" (each frequency represents a colour). By using the Doppler effect it is possible to detect specifically only moving objects.