Abstract: This specification discloses a scanning illuminating device in a copying apparatus of the slit exposure type in which a movable slit area of an original is projected upon a movable photosensitive medium by a projection lens. The device is characterized in that light sources are fixed to the opposite end portions of the original surface with respect to the scanning direction, the magnification of the light source image becomes gradually greater at one end of the scanning direction and gradually smaller at the other end of the scanning direction, and imaging elements are moved in the scanning direction so that the illumination distribution on the original surface is formed so as to compensate for the loss of quantity of light of the projection lens due to the so-called cos biquadratic rule or the like to thereby enable copying of uniform density in the scanning direction.

Abstract: Positive lens-negative lens type complete symmetrical lens system varies in focal length with the change of temperature. According to the invention, such change of the focal length caused by the change of temperature is compensable between the two adjoining positive and negative lenses. Furthermore, the possible displacement of focus is reduced to a value less than 0.3 mm in the temperature range at which the lens system is generally used.

Abstract: A scanning illuminator has a compact structure suitable for use in high speed copying machines and is adapted to reflect light beams from two light sources fixed adjacent to the opposite ends of an original supporting area to the surface of an original by means of rotary mirrors and translating mirrors for illuminating the original surface in a slit shape. The scanning illuminator has a flexibility in optical adjustment.

Abstract: A scanning illuminator suitable for use in high speed copying machines is adapted to compensate the distribution of loss in light quantity with respect to an imaging lens due to the so-called Cos.sup.4 law in the scanning direction and includes fixed sources of light. The scanning illuminator is characterized by illuminating systems disposed symmetrically relative to an original supporting area, each illuminating system being adapted for illuminating the opposite end areas of an original by a portion of light beam from the fixed source of light adjacent one end of the original, especially the light beam portion emitted and bled backward of the light source, the illuminating system having at least one rotating or translating scan mirror for scanning the illuminating light beam.

Abstract: A color television camera utilizing a compact color separation optical system including three prisms wherein a first prism counted from the objective lens side has an entrance face, a junction face and an exit face, a second prism has a first prism junction face, a third prism junction face and an exit face, and a third prism has a junction face and an exit face.

Abstract: A TV camera which can detect any object distance. The image pick-up surface of the TV camera is divided into an object image forming surface and a range finding image forming surface. The object distance can be detected by reading the range finding image.

Abstract: A dichroic mirror made of at least ten or more alternate high refractive index and low refractive index layers for a designed wave length expressed by .lambda.o, basic optical film thickness of the high refractive index layers are represented by 1/4.lambda.o and 3/4.lambda.o, while the basic optical film thickness of the low refractive index layers is represented by 1/4.lambda.o. Thickness of the first layer, the second layer and the last layer as counted from a substrate, also of at least one layer of other intermediate layers are shifted from the basic optical film thickness, so that properties of the mirror are improved and a production thereof is made easier.