OPTICAL SYSTEMS WITH AXIAL MIRRORS

摘要

1,152,018. Optical systems; electrophotographic apparatus. EASTMAN KODAK CO. June 5, 1967 [June 8, 1966], No.25889/67. Headings G2H and G2J. An optical system for forming a real image of an object comprises at least one unit comprising an objective 10 and a plane reflector 11, 12 lying on the optical axis thereof and between the objective and both the object and image planes 13, 14 thereof. The object may be moved so that the unit scans the object in a direction perpendicular to the axial mirror, Fig.2 (not shown), or a stack of units may be used to produce an image of a whole document, Figs. 3, 4 (not shown). A further plane reflector parallel to the axial mirror may be provided, and the objective may be in the form of a concave reflector, Fig. 7 (not shown), or in the form of a segment of a spherical lens. In another embodiment, Fig. 6 (not shown), each unit contains two blocks (38, 42) having coplanar reflector forming surfaces (41) and mutually facing surfaces (40) which are curved to form an air lens forming the objective. In two other embodiments, Figs. 16, 22 (not shown) four or three plane reflecting surfaces form the inside surfaces of a regular prism having rectangular sides, which prism extends on to the sides of the objective formed by four quadrants or three segments of spherical lenses having their optical axes along the intersection lines of adjacent pairs of the reflecting surfaces. Several units as described in connection with (Fig. 6) are arranged side by side to copy a document 140 Fig. 20 which is moved by a roller 141 past an object gate 117 for line by line scanning. Light from a lamp 142 falls on the document and is reflected along the units, via the air lenses, to the image gate 118 where it falls on a charged paper sheet coated on one side with photoconductive zinc oxide in resin. The exposed sheet passes through a liquid toning bath 155.