GB1410903A - Scanning device - Google Patents

Abstract

1410903 Scanning PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd 22 March 1974 [30 March 1973] 12830/74 Heading H4F A scanning device which may be used in an endoscope, comprises two resilient strips of magnetizable material 2, 4 arranged as shown with their planes at right-angles to each other, one end of strip 2 being clamped at 1; the strips 2, 4 have respective mechanical resonant frequencies F2, F1 where F1 = n. F2+X, n, F2 and X being integers. The strips are magnetized by a continuous magnetic field having a northsouth direction N-S at 45 degrees to each of the planes of the strips 2, 4 provided by a permanent magnet 5, and alternating magnetic fields mainly parallel to the longitudinal direction of the strips 2, 4 and oscillating at frequencies F1 and F2 are produced by a coil 6 receiving an electric current composed of two currents having the frequencies F1 and F2. The strips 2 and 4 oscillate at their respective resonant frequencies and the free end of strip 4 describes a Lissajous figure in a rectangle f times per second, f being the largest common denominator of F2 and X. An endoscope incorporating the scanning device has at least one flexible light conductor (9, Fig. 2, not shown) supported by the strips 2, 4 and connected to a photomultiplier or, for colour, to a beam splitter, coloured filters, and three photomultipliers; one light conductor may be provided for green light, and a second light conductor, of twice the diameter of the first light conductor, may be provided for blue and red light. Light for illuminating the subject being scanned may be provided from a lamp via alight conductor in the vicinity of the above light conductor(s), (9), or via a number of light conductors (10, Fig. 2, not shown) carried in grooves in the outer surfaces of the housing (7) containing the scanning device.