GB989644A - Improvements in scanner and microscope - Google Patents

Abstract

989, 644. Photo-electric measurement; electric measuring instruments. INSTITUTE FOR CANCER RESEARCH. April 16, 1962 [Oct. 18, 1961], No. 14657/62. Heading G1A. [Also in Divisions G2 and H4] Ultra-violet light derived from a source 20 (e.g. a xenon arc) by way of a monochromator 22 is scanned over a specimen 50 by means of a mirror 25 which is carried by a support 26 which is pivoted at 27 in a frame 28, the support being oscillated about the pivots to introduce a first component of scanning by means of an electromagnet system 32, 33 which co-operates with an armature arm 30 extending from support 26, and the frame 28 being oscillated in bearings 40 to introduce a second component of scanning by an arm 41 which engages a rotating cam 43 (see Fig. 2). The armature carries a weight 31 adjustably threaded on the armature, and the lower end of support 26 carries a leaf spring 34 which is secured so as to slide longitudinally between members 35, 36. Inward motion of the armature is limited by a rubber bumper 37. The mirror, support, armature, weight and leaf spring form a vibrating system which is adjusted to be resonant at the frequency of the alternating current applied to the electro-magnet solenoid 33. The scanning motion imparted by the mirror is substantially sinusoidal. In order to employ only the linear portion of the motion and, further, to restrict the scanning to one direction only, a shutter 54 (see Fig. 3) is rotated in the light beam between monochromator 22 and the mirror. The pin-point exit of the monochromator is imaged on the specimen by means of optical system 45, 46. The light passing through the specimen is detected by a photomultiplier 51. The resulting electric signal may be employed to reproduce an image on a cathoderay tube scanned synchronously with the mirror, Fig. 5 (not shown), or may be applied to an integrator and counter circuit to provide a measurement of the specimen density over the scanned area, Fig. 6 (not shown). Reference is made, without giving details, to the use with the invention of visible and infra-red light.