Abstract: An image forming optical system especially suitable as a viewfinder system in an electronic or electronic/film (hybrid) camera includes an objective lens system, an electronic imaging channel, and a visual viewfinding imaging channel. The objective lens system is common to both the electronic and visual imaging channels, and provides a zoom function. The objective lens system is substantially afocal. The optical system includes an optical component that provides at least three reflections for the visual viewfinder image forming light.

Abstract: A lens for use in optical disc players comprising a single biconvex element having both surfaces aspheric. The refractive index, N.sub.D, of the element at 589.3 nm is 1.492 and at the same wavelength the Abbe V number is 57.4. At 800 nm the refractive index, N.sub.800, of the element is 1.48584. Each surface may be described by the equation: ##EQU1## wherein: X is the sag of the aspheric surface from a plane reference surface at a radial distance Y from the axis of the lens.______________________________________ Surface 1 Surface 2 ______________________________________ C = 0.354021 -0.1557360 K = 0.0 -20.4938239 D = -0.2909441 .times. 10.sup.-2 0.0 E = -0.5163209 .times. 10.sup.-3 0.0 F = 0.5075886 .times. 10.sup.-4 0.0 G = -0.1399892 .times. 10.sup.-4 0.