GB200929A - Improvements in apparatus for copying documents, drawings, and the like - Google Patents

Abstract

200,929. Pollock, J. April 22, 1922. Camera lucidas.- Relates to camera lucidas of the kind comprising a glass reflecting-plate held in a vertical position across the centre of a drawing-board or the like or between two such boards, for copying documents, drawings, &c. or tracing over their reflected outlines. The reflecting-plate c, Fig. 1, is made of coloured or clear glass, or of glass in combination with other transparent substances, and one or more screens c<1> are placed at the sides of, and above, the copying-surface to regulate the nature and intensity of the light falling thereon. The screens may be of the same material as the reflector, or of paper, fabric, &c. The reflector and screens may be supported on a board a, Fig. 1, or the apparatus may be constructed from photographic dark-slides, as shown in Fig. 2, the shutters being remorved from the hinged frame E, and replaced by reflecting-plates and screens a. Photographic printing-frames, school slate frames, or the like may be used to hold the reflector and screens, or these may be supported by brackets, stands, &c. Means may be provided for inclining the reflector to the vertical plane to enable corrections or adjustments to be made, and to permit copies of different width from the original to be produced. The surfaces on which the original and copy are placed may be adjustable in height, or separate holders may be provided for raising and lowering the objects to be copied.