JPS56120173A - Solid state image sensing device - Google Patents

Abstract

PURPOSE:To secure the reading of a printing type by making a light acceptance portion of a solid state image sensing device rectangle, setting a long side and a short side thereof as the horizontal and vertical scanning direction respectively and thereby increasing the resolution with respect to the side lines. CONSTITUTION:A window 15 of a light sheltering plate is a reactangle. For instance, the length of the short side in the vertical scanning direction is 1/2 of that of the long side in the horizontal direction. The breadth of a horizontal scanning line which passes is 1/2 of a scanning period as usual (equal to the short side). The black and white information with respect to the horizontal lines (meshes) 12 which pass through the window 15 is obtained at a timing A-a-A-c. The informaton B-a-B-c, and B-a'-B-c' are obtained from the first and the second scannings respectively and more than 50% black information is always included in any one of them. Accordingly, when it is binarized by black an white, the breadth of the black signal becomes narrow in special case, but the horizontal lines are detected surely. If the light acceptance surface of a photoelectric conversion portion is formed like a window 15, there exists no need of the light sheltering plate. The degree of resolution order increases considerably by this constition, and the reading of the printing type becomes sure.