GB712490A - Apparatus for endoscopic examination - Google Patents

Abstract

712,490. Television. SHELDON, E. E. May 10, 1951, No. 10976/51. Class 40 (3). [Also in Group VI] In a surgical endoscope an image of the examined part is converted into electric signals which are passed to an external receiver where a picture of the part is formed on the screen of a cathode-ray tube. In the basic form of the device an endoscopic tube 1, Fig. 1, contains a lamp 7 for projecting light on to the examined part and an image of the part is received through a prism 20 and lens 21 by the cathode of a miniature pick-up tube 16. This is connected to external amplifying and synchronizing circuits from which the signals are passed to a viewing tube 37. In an alternative form illumination is by a flying-spot kinescope, in which case the photosensitive element may be an electron multiplier photocell or a selenium cell. It is also proposed to introduce colour, either by employing a rotating colour disc, driven by a motor synchronized by pulses from the transmitting circuits, (see Fig. 4, not shown), or by three simultaneous transmissions of images in the primary colours. In the latter case a flying-spot kinescope 119 illuminates the field to be viewed and the image received by lens 144 is divided into its primary colours by crossed dichroic reflectors 145, 146 so that corresponding images are received by photo-cells 137, 138, 139. The signals are amplified and transmitted in the normal manner and the corresponding pictures on the screens of tubes 162, 163, 164 are projected simultaneously on to a screen 168.