GB884692A - Pin registration system of producing slide transparencies for overhead projection - Google Patents

Abstract

884,692. Slide transparencies. TECNIFAX CORPORATION. Jan. 29, 1960 [March 3, 1959], No. 3230/60. Class 98(2). A slide transparency is made up of a number of separate transparencies in register; these are printed from master sheets carrying designs or coloured images, these master sheets being prepared one by one on a registratiori board having locating pins which engage in holes in the sheets, to ensure correct registration; the prints are made by exposing the master sheets and film sheets to illumination while located on the registration board, the said board again being used to assemble the final transparencies in correct registration. Fig. 1 shows a drawing being prepared on a single master sheet 20, which lies on a board 16 having three registration pins 18, the pins passing through holes 22 in the sheet. An underlying grid sheet 23 may be provided to facilitate drawing the design. A second master sheet 20<SP>1</SP> is placed over the first (Fig. 2), and further designs or images made thereon, so that the two sheets 20, 20<SP>1</SP> together provide a composite design. In the example shown, sheet 20 carries the outline. of a house, and sheet 20<SP>1</SP> the door and windows. Further master sheets are prepared as required. Prints are then made from the master sheets, one by one, by placing a master sheet and a lightsensitive film sheet in correct registration on the board, and exposing to light. A more detailed description of the method of printing, and the apparatus therefor, is given in Specification 881,029. After the prints are developed, they are assembled by once more using the registration board 16. A frame 70 is located on the board by the pins 18, and the successive transparency sheets, all of which have locating holes for the pins 18, are placed in correctly registered superposition. In the example of Fig. 6, all the transparencies are permanently secured in superposed position by adhesive strips 76 along the edges ("static" slides). In the example of Fig. 9, the two transparencies 78 and 87 are hinged to the frame 70, as at 80, so that either, both, or neither. may be swung into superposed registration with transparency 24 ("dynamic" slides).