GB1244193A - Improvements in and relating to optical arrangements - Google Patents

Abstract

1,244,193. Optical arrangements for cameras; lenses. RICOH K.K. Aug.29, 1968 [Sept.11, 1967(2)], No.41201/68. Headings G2A and G2J. In a camera for producing a number of exposures on the picture area of a photo-sensitive sheet, the optical arrangement is in the form of a first lens 11 (or 21) having a curved focal plane at which the image I is formed, an aperture 13 (or 23) adjacent to or within the first lens and movable in a plane perpendicular to the optical axis, and a second lens 12 (or 22) having a plurality of microlens elements on the near face which focus on the further face. In the first form, shown in Fig.2, the second lens 12 has a focal plane of the same curvature as the image I, so that the perpendicular distance between each portion of the image I and the corresponding point on the second lens is substantially the same. The image I is split into discrete portions, each of which is sharply focused upon the photo-sensitive material 14 mounted on the rear surface of lens 12. The aperture can be displaced into various positions, e.g. by seven equal steps in both vertical and horizontal directions, each of which will produce a record on a different portion of the photo-sensitive sheet 14. In the second form, shown in Fig.3, the second lens has its mirco-elements disposed in a plane, and not in a curve as in Fig.2. The focal length of the micro-lens elements varies according to the distance of the element from the image plane I. Thus the element at a distance a from plane I will have a different focal length from the element at a distance aa. The focal length is such that each element produces a sharply focused image on the photo-sensitive sheet 24 on the further face of lens 22.