GB1354993A - Pattern processing apparatus - Google Patents

Abstract

1354993 Pattern and character recognition systems TOKYO SHIBAURA ELECTRIC CO Ltd 12 July 1972 [15 July 1971 (2)] 32548/72 Heading G4R [Also in Division H1] An image converter tube for use in character or pattern recognition apparatus, comprises a photo-cathode for converting an input optical image into an electron image, an array of output electrodes, a zoom lens for focusing the electron image on the output array with variable magnification, and means for deflecting the electron image so that a selected portion may be centred over the array. The output electrodes may be arranged in a 32 x 32 matrix. Pattern identification, Fig. 3.-Cancer cells may be identified in a photograph of dyed cells which is projected on the photo-cathode 31. The output signals on lines 39 (of which five are shown to represent the array of.32 Î 32) are fed to units 37 where they are compared with the maximum signal detected by unit 35. The outputs of the comparators 37 are transformed to binary signals by quantizing circuits 38 which indicate the co-ordinate of the area of maximum signals. These co-ordinates are transformed into deflection signals which are fed to the deflection coils to centre this area on the output electrodes. When the output of unit 35 exceeds a threshold value a zoom command increases the magnification of the focusing coils so that a magnified image of the selected area is projected on to the output electrodes which feed known processing circuits 32-34 which identify the pattern, and after this has been done a signal from unit 34 to focus control 44 restores the initial conditions. Character recognition, Fig. 5.-A pattern including a number of digits or letters is projected on to the converter tube 51, of which the output leads 52 are illustrated as a 5 Î 5 matrix. The signals on the leads are quantized into ones and zeroes in unit 53 and passed to an OR gate matrix 54. The vertical and horizontal projections of the digits are formed in registers 59, 60, Fig. 7B. Registers 59, 60 feed unit 61 which moves the image upwards and to the left until a " one " is present at the end cells of registers 59 and 60 (Fig. 7D, not shown) indicating that a digit is located at the top left corner as required. The height of the digit is measured by unit 69 which counts the number of " ones " in register 64, and the lens control 70 is operated to enlarge the digit to a standard height, whilst at the same time the deflection control 61 is adjusted so that the enlarged image of the digit remains at the top left corner. An isolating circuit 71 controlled by registers 59 and 60 allows signals from conductors 52 corresponding to the selected enlarged digit, and only those signals, to pass to a recognition circuit 76 of known type; when the operation is complete, a signal to control circuit 61 prepares the apparatus for reading the next digit or letter.