| 摘要 |
1,235,081. Photographic type-composing. INTERNATIONAL BUSINESS MACHINES CORP. 1 Jan., 1970 [15 Jan., 1969], No. 135/70. Heading B6W. [Also in Divisions G2 and G4] An optical character generator comprises a light source 12 from which a beam is directed in response to a character address input 21 on to a selected character area of a multiple character mask 19 and the resulting character-bearing beam is directed on to a target 15, a light sensor 37 which receives a portion of the light transmitted from the mask to produce a coded indication of the character formed by the mask, and a comparator 44 for comparing the coded indication of the character transmitted and the character address to provide an error signal 45 when there is no match. Each character on the mask 19 is surrounded by an annular area in which a binary code representing the character is formed, a character being selected by a binary address signal 21 applied to deflectors 13, 14 comprising birefringent and electro-optic crystals. The selected character is transmitted to the target 15 via a beam splitter 36 and an apertured member 38 which blocks the code representation of the character. The beam splitter directs the code representation signal to light sensitive semi-conductor diodes 40, the signal from which is compared with the address signal in the comparator 44. In a similar manner, the position of the transmitted character is compared with the required position using a beam splitter 48, a light sensor 53 and a comparator 54. A modification is described in which the character and its coded representation are separated on the mask 19, light of one wavelength being used to transmit the character whilst light of a second wavelength transmits the code representation signals. The target may comprise a recording medium, a ground glass. plate or a cathode-ray tube and the apparatus is used for checking optical printers. |
