“Another method of producing a line screen was patented in 1904 by the German Robert Krayn, and was demonstrated by him in November 1907. Krayn stained very thin celluloid sheets red, green and blue, and cemented them interleaved to form a thick block from which thin slices were cut. Krayn was able to produce sheets of line screens up to 16 x 12 inches (40.6 x 30.5 cm) in size, with 175 colour lines to the inch (69 to the cm). Krayn’s process had a very limited commercial use, and in 1908 a finer screen, of 254 lines to the inch (100 to the cm) proved no more successful, the film being very prone to split along the lines of the cementing. By recementing the sliced sheets and slicing the block again, Krayn also produced a mosaic screen, but this was no improvement.”
(Coe, Brian (1978): Colour Photography. The First Hundred Years 1840-1940. London: Ash & Grant, p. 54.)
Original Technical Papers and Primary Sources
Silbermann, 1, 235; abst. British Journal of Photography, 1907, 54, Col. Phot. Supp. 1, 80; J. S. C. I. 1903, 22, 923; Handbuch, 1917,4, II, 195; Phot. News, 1906, 50, 1040; Belg.P. 150,329, 1900; Phot. Coul. 1908, 3, 124.
Coe, Brian (1978): Colour Photography. The First Hundred Years 1840-1940. London: Ash & Grant, p. 54.
Friedman, Joseph Solomon (1945): History of Color Photography. Boston: The American Photographic Publishing Company, p. 153.
Mees, C. E. Kenneth (1928): The Processes of Color Photography. II. Screen Plate Processes. In. The Journal of Chemical Education, 1928, 5,12, pp. 1577-1582, on pp. 1580-1581.
Pénichon, Sylvie (2013): Twentieth Century Colour Photographs. The Complete Guide to Processes, Identification & Preservation. London, Los Angeles: Thames & Hudson, on pp. 34–36and on p. 75.
Wall, E.J. (1925): The History of Three-color Photography. Boston: American Photographic Pub. Co., p. 327.
Fr. P. 357895, additions 5375, 6534, 6536, 6537; 386772 and 409367 (Friedmann)