INLET PART OF ENDOSCOPE Russian patent published in 2002 - IPC

FIELD: optical instrumentation. SUBSTANCE: invention can find use in optical systems of flexible and rigid endoscopes of small diameter meant for observation of internal spaces during endoscopic examinations in medicine and in various fields of technology. Inlet part of endoscope has objective made up of four components, aperture diaphragm installed between first and second components and image transmission system. First component of objective is planoconcave lens with concave surface concentric on aperture diaphragm, second component presents positive lens manufactured in the form of ball, third component comes in the form of biconvex lens with focal power amounting to 0.4-0.7 equivalent focal power of objective, fourth component is planoconcave lens facing image transmission system with flat surface. Aperture diaphragm is matched with vertex of lens-ball. EFFECT: raised quality of image of observed objects thanks to reduction of distortion to minimum. 3 cl, 2 dwg _