Abstract: A symmetrical light intensity distribution profile is achieved by placing a pair of similar asymmetrical linear DC gas discharge lamps in parallel position but opposed in polarity. The individual asymmetrical distributions of the lamps combine in a symmetrical total intensity distribution. A desired "butterfly" or other intensity distribution profile can be achieved.

Abstract: A latensifier for developing latent images recorded on direct print paper includes a pair of generally U-shaped fluorescent lamps mounted to expose the paper to latensifying radiations, the planes of said lamps being disposed at a right angle to each other, with a neutral density step filter arranged in association with one of the lamps to control pre-conditioning radiation to the paper, reflectors operatively associated with the second of the lamps to control additional pre-conditioning radiation to the paper and also to allow maximum use of the second lamp for recorded image development, the second lamp being selectively energized in accordance with the speed of relative movement of the lamps and paper.

Abstract: A photographic light source has a boxlike frame with sockets for mounting and electrically connecting, for continuous operation, fluorescent white light tubes of conventional type distributed about the inner sides of the frame and extending longitudinally of them. Reflectors with light diffusing reflecting surfaces are mounted to extend between the sockets and about light tubes mounted therein, the reflectors having a position in which most of the light from the tubes is directed and reflected into the frame and mainly toward one face of it. The mixture of direct and reflected light reflected by a subject within the frame, or outside that face of it, toward a camera directed into the opposite face of the frame, provides effective lighting for color or black and white pictures, with the predominant green of directly reflected light from such tubes desirably suppressed. Adapters are provided for using the frame for slide viewing and photographing.

Abstract: Apparatus for reproducing a half-tone image of an original comprises a support, preferably in the form of a cylinder, for a light-sensitive record medium, an exposing head for exposing a record medium on the support, and means preferably in the form of a mechanism for rotating the cylinder and a lead screw for moving the head axially of the cylinder, to produce a relative scanning motion between the exposing head and the record medium. The exposing head includes a row of side-by-side light modulators or light sources extending in a direction such that the areas illuminated by the modulators or sources on the record medium extend in a direction across the width of a scanning line on the record medium. The area of illumination of the record medium provided by each light modulator or source varies in the said direction and is of lower intensity at its ends than at its middle and each area overlaps the areas of illumination provided by adjacent modulators or sources.

Abstract: Exposure control for an image projecting system, particularly for a projection system in which an image is projected from an illuminated object plane through a lens and onto an image plane of a copier of the full frame exposure type. Illumination means are employed for illuminating an object plane. Transducer means, preferably in the form of a photosensor, are provided in the light path and on the image side of a lens for primarily sensing the intensity of the light incident on the image plane. The transducer means produce an output signal which varies in accordance with the intensity of the projected image, and integrating means coupled to the transducer are adapted to produce a time integral output signal of the intensity of the illumination sensed by said transducer means. Means are further provided for discontinuing the illumination of the object plane by the illumination means when the time integral output signal reaches a predetermined level.

Abstract: An electrophotographic copying machine having a moving photoconductive member, in which an original document is illuminated by a pair of light sources, which are energized alternately to illuminate the document at a frequency of 240 hertz. This frequency of illumination prevents visible lines in the copy.

Abstract: An apparatus for photocopying a document on a surface including a camera having a lens directed at the surface and a pair of illumination housings adjacent opposite edges of the surface for illuminating the surface with diffused light. The illumination housings are of sufficient height to reduce the amount of external light which shines on the surface.

Abstract: An image transmission means for employment in a photocopying machine wherein a document to be copied is scanned and image-wise light reflected therefrom is directed onto a photosensitive medium which is moved at a speed equal or proportional to the document scanning speed. The image transmission means comprises an image-transmitting light-conducting fiber array which transmits image light reflected from a document onto a photosensitive medium, and is so mounted that photosensitive medium portions which are less exposed due to characteristic variation in light transmission efficiency of different portions of the fiber array are disposed longitudinally with respect to the document image. Illumination of a document is provided by one or two tubular alternating current fluorescent lamps which are actuated to provide illumination which varies at a frequency and to a proportion that are selected with reference to the characteristic variations of different portions of the light-conducting fiber array.

Abstract: A document photographing device has a surface for supporting a document to be photographed, a camera positioned about the surface, to receive light reflected from and transmitted by a document supported on the surface, and separate means for illuminating the document from above and below respectively. An exposure meter receives light reflected from or transmitted through the document and indicates when correct exposure conditions have been set. The exposure meter includes correction means for correcting the reading of the exposure meter to take account of the different spectral radiation characteristics of the illuminating means.

Abstract: An illumination means for use in association with a SELFOC image transmitter in a photocopying machine. The illumination means comprises at least one light generator in the form of a tubular fluorescent lamp or similar means emitting light through a slit disposed parallel to the longitudinal axis thereof, and an associated light-guide which is made of glass, plastic, or other material having a high refractive index, is generally equal in length to the light-generator, has a generally trapezoidal cross-section, and directs light emitted by the light-generator into an illumination slot or shutter means provided in or below a document rest for illumination of successive portions of a document to be copied, the light-guide broad base and narrow base being proximate to, in line with, and generally equal in width to the light-generator slit and the document rest slot, respectively.

Abstract: Apparatus for graphic arts plate making suitable for exposing diazo plates and the like. A unit providing an exposure bed with a plurality of lamps close to the negative and plate and operating in the ultraviolet region, and another plurality of lamps in the visible light region with a diffused glass top for a work table and for fixing an exposed plate. Separate control units for each exposure lamp to provide uniform radiation from all lamps to the plate.