Projection device

Abstract

This specification discloses a compact projection device in which lens systems extending in the direction of the optic axis for projecting a part area of an object upon a predetermined part area on an image plane (hereinafter referred to as element lens systems) are initially set by a lens holding member having groove portions or hole portions extending in the direction of the optic axis, the distributions of intensity of light of the element lens systems on the image plane are controlled by an aperture eclipse such that the intensity of light is weaker in the marginal area than at least in the central area, a plurality of such element lens systems are arranged in a predetermined direction in a plane perpendicular to the optic axis and the distributions of intensity of light of the element lens systems are suitably superposed upon one another at least in the marginal area to provide uniformity of the distribution of the exposure amount integrated in the scanning direction with respect to the lengthwise direction of the slit of a copying machine of the slit exposure type. The element lens system each comprises two bar lenses each having a great length in the direction of the optic axis thereof as compared with the effective diameter thereof, and an intermediate image is once formed between the bar lenses and finally, a one-to-one magnification image is provided. The element lens systems are arranged in more than two rows in a honeycomb-like fashion such that the element lens systems of each row are positioned intermediate the element lens systems of the other row as viewed in the direction of the optic axis, whereby the uniformity of the distribution of the exposure amount integrated in the scanning direction with respect to the lengthwise direction of the slit is improved.

Dependencies are inferred from the claim text.