TELEVISION WIDE-ANGLE LENS WITH REMOTE ENTRANCE PUPIL AND EXTENDED REAR FOCAL LENGTH Russian patent published in 1999 - IPC

FIELD: television. SUBSTANCE: television wide-angle lens with remote entrance pupil and extended rear focal length is related to field of optical instrumentation and is used in miniature black-and-white and color cameras on CCD matrixes. Lens with remote entrance pupil has three components: first component is fabricated in the form of negative meniscus facing space of objects with concavity which absolute value of second radius amounts to summary thickness of meniscus along axis and distance to entrance pupil as minimum, second component is positive biconvex lens and third component presents cemented meniscus facing space of objects with convexity that can have both positive and negative focal power. Besides that first negative meniscus can be cemented together from two positive and negative meniscuses with radii of same sign or can be cemented together from two lenses, biconcave and biconvex. EFFECT: possibility to increase rear focal length and uniformity of field illumination. 9 cl, 4 dwg, 2 tbl