Abstract: An image reading device capable of reading a projected image has a lens array for forming an image from the projected light. Upbeam of the lens array is disposed a diffusion member which diffuses the luminous flux of the projected light. Preferably, a Fresnel lens is disposed to receive the projected light, and the diffusion member is a lower surface of the Fresnel lens which has been subjected to a surface-roughening treatment.

Abstract: An optical information recording medium includes a plurality of kinds of pits independently representing information and having different depths, wherein the plurality of kinds of pits are formed as portions recessed from the same plane. A method of reproducing information is disclosed, which includes irradiating this medium with a plurality of light beams having different wavelengths corresponding to the depths of the plurality of kinds of pits; and independently detecting the beams modulated by the pits. An optical information reproducing apparatus is also disclosed.

Abstract: A light scanning optical system of an image output scanner comprises an electro-mechanical light modulator comprising a number of elements irradiated with a light beam from a light source and capable of deflecting the light beam in at least two directions in accordance with an input signal, the elements being arranged in the main scan direction, each of the elements making image information by the change-over of the direction of deflection, and a projection optical system for projecting only the signal light of the image information. The optical axis of the projection optical system is perpendicular to the array of the element of the modulator.

Abstract: A light scanning optical system of an image output scanner comprises an irradiating optical system, an electro-mechanical light modulator comprising a number of elements on which a light beam is incident from a light source through the irradiating optical system and which are capable of deflecting the light beam in at least two directions in accordance with an input signal, the elements being arranged in the main scan direction, the elements making image information by the change-over of the direction of deflection, and a projection optical system for projecting only the signal light of the image information, the image of the light source being set so as to be formed on the entrance pupil of the projection optical system at a magnification in the vicinity of one-to-one magnification.

Abstract: In an imaging optical system, the angular aperture of distributed index optical elements which are optical elements forming the imaging optical system is 9.degree. or greater and the degree of superposition M of images on a light-receiving surface is M=2.75+0.5x. The degree of superposition M of images is represented by M=X.sub.0 /D, where D is the effective diameter of the optical elements and X.sub.0 is the field radius thereof. Also, x is 0 or a greater integer.

Abstract: An image exposing apparatus comprises a focusing optical system for focusing an image onto a photosensitive member and having a one-line array of a plurality of focusing light transmission media, and light intensity distribution correction means arranged in a light path for forming the image for eliminating an ununiformity of light intensity on the photosensitive member due to the focusing optical system.