Abstract: A camera system in which information is transmitted between a camera body and an accessory in the form of a current signal is provided. A voltage-to-current converter is provided in at least either one of the camera body and accessory and a current-to-voltage converter is provided in at least the other of the camera body and accessory. Thus, analog information can be transmitted between the camera body and the accessory with high accuracy even if they have separate voltage sources different in level.

Abstract: A focusing position detection circuit provided with a pair of light receiving element arrays respectively disposed in front of and behind a predetermined focusing plane of an optical system, capable of determining the position of the optical system by the output signals of the light receiving element arrays, and outputting an analog signal corresponding to the position of the optical system in the defocused range, but in the focused range with a predetermined tolerance, outputting a focused signal at a predetermined level.

Abstract: A hologram lens capable of converting an output beam of light emitted from a semiconductor to a reconstruction light suitable for reconstructing holograms is prepared by use of the object light, which resembles a beam of light emitted divergently from a semiconductor laser for reconstructing holograms and which travels, in the opposite direction to the travelling direction of the beam of light from the semiconductor laser, in such a manner as to converge on a light emitting portion of the semiconductor laser, and the reference light which is an isotropic beam with a circular cross section.

Abstract: A mark placed on the original support plate outside the original support zone for adjusting the position of a solid-state line image sensor of a line-by-line image dissecting system including a first mark member extending in a direction perpendicular to the auxiliary scanning direction of an original, and a second mark member parallel to the first mark member and spaced apart therefrom by a spacing interval substantially equal to the width of an array of light receiving elements of the solid-state line image sensor when projected on the surface of the sensor as an image of a reduced scale. The first mark member includes a solid straight line or a broken straight line, and the second mark member includes one or a plurality of broken straight lines parallel to one another. Dashes constituting each broken straight line are spaced apart from one another by a spacing interval which differs from one broken straight line to another, to enable different broken straight lines to be distinguished from one another.

Abstract: An improved focusing position detection apparatus is capable of detecting a focusing position speedily by use of a single photoelectric conversion element array. The photoelectric conversion element array is positioned so that the opposite end portions of the element array are at different distances, physically or optically, from an object and the photoelectric conversion element array is divided into three portions, the opposite end portions and an intermediate portion, and the electric output from each portion of the photoelectric conversion element is analyzed, whereby the moving direction of an optical system for obtaining the focusing position is determined.

Abstract: A microfiche on which a large number of characters are formed in an alternating arrangement is movable behind a mask in such a manner that at each position of the microfiche relative to the mask a desired group of characters is displayed through respective apertures in the mask. Lenses are disposed behind the apertures to project images of the characters therethrough onto a viewing screen. A reflection support member is disposed behind the microfiche and is formed with a stepped surface on which are disposed a plurality of concave reflectors, one reflector behind each lens. A lamp radiates light onto the reflectors, from which the light is reflected and focussed into the respective lenses, thereby illuminating the characters on the microfiche from behind. The radii of curvature and light receiving frontal areas of the reflectors differ in accordance with the distances of the reflectors from the lamp and the respective lenses.

Abstract: A light transmitting screen capable of directing and focusing light images falling thereon, comprising a plurality of lens systems, each having a particular optical axis, making up the screen elements and each of which transmits parallel light rays incident thereon such that the light rays emerge parallel to each other. The lens systems may be of different refractive powers and have their optical axes disposed in parallel or at varying angles with each other and all are adjacently arranged in the form of a flat, curved or segmented screen with front and rear surfaces. When light is incident upon the screen from one side, the light rays pass through and are directed by the individual systems in accordance with the arrangement of their optical axes and refractive powers, so that many varying optical and lighting effects may be achieved on the other side. Each lens system may comprise a series of suitable lens surfaces arranged on a common optical axis or an optical cylinder or fiber guide.

Abstract: A mark counter is able to count frame marks in one film margin adjacent to corresponding frames and group marks in the other film margin adjacent to the first frames of each group of frames regardless of which margin contains the frame marks and which margin contains the group marks. The marks in both margins are sensed, and analogous signals are fed into an OR gate and an AND gate. The output of the OR gate is the logical sum of the number of sensed frame and group marks which is numerically equal to the number of sensed frame marks, and the output of the AND gate is the logical product of the number of sensed frame and group marks which is numerically equal to the number of sensed group marks.