公开(公告)号：DE1202043B

公开(公告)日：1965-09-30

申请号：DEJ0022460

申请日：1962-10-04

Applicant: IBM

Inventor： JUN GLENMORE L SHELTON

IPC: G06K9/74

Abstract: 1,013,129. Automatic character reading. INTERNATIONAL BUSINESS MACHINES CORPORATION. Oct. 1, 1962 [Oct. 5, 1961], No. 37076/62. Heading G4R. In a pattern identification apparatus of the kind in which the autocorrelation function of the pattern is derived optically, the light source is polarized in a first plane and the autocorrelation function is formed as a pattern of elliptically polarized light which is passed through an analyser opaque to the plane polarized light. In the form of Fig. 1, the character 28 is scanned to derive a succession of signals representing the elemental areas. These are impressed as compression-waves in a light valve 18, each compressed part having the property that the plane polarized light passing through it becomes elliptically polarized. At a certain instant after scanning the compressed areas representing the black parts of the character are positioned somewhere near the middle of the valve 18. This pattern is autocorrelated by an area of light 10 plane polarized at 12 and reflected from halfmirror through a collimating lens 16 and through the travelling pattern in light valve 18. A mirror 34 reflects the light and returns it through the light valve where light passing through the compressed parts are further elliptically polarized, and through the analyser 36 where the plane polarized light is cut out. A strip pattern of varying brightness therefore forms on ground glass screen 38 which represents the autocorrelation function of the character, as indicated in Figs. 3a, 3b. Transparencies 40, one for each possible character, are placed behind the screen each having 45 strips of varying opacity representing the autocorrelation functions of the corresponding characters. Behind each transparency 40 is a normalizing transparency 42 having an opacity such that the maximum light passed (i.e. when the corresponding character is being sensed) is the same in each case. The light transmitted is stored on a phosphor sheet 43 which serves as an integrator and strip photocells 44 give output signals proportional to the light passed the maximum signal coming from the mask and photo-cell corresponding to the character being scanned. Circuit 46 determines the lead having the highest signal. The normalizing transparencies 42 may be replaced by normalizing potentiometers in series with photo-conductors which replace the photo-cells. Since in practice the light valve is not optically perfect a compensator 32 is provided to remove elliptically polarized light produced by the light valve in its quiescent state. The compensator is adjusted so that no light is transmitted to the screen when the valve 18 is quiescent. In the form of Fig. 16 the character is mounted on a transparency and a two-dimensional autocorrelation pattern is obtained in a way similar to that described above. In the embodiment of Fig. 16, however, the source light is plane polarized at 82. It is transmitted by halfmirror 86 and lens 88 through the transparency and a one-eighth wavelength delay plate 92 and reflected by mirror 94 back again through a polarizer 98 to form a two-dimensional pattern on the screen 96. This pattern is compared with reference patterns as before. The delay plate 92 causes the autocorrelation function to be a pattern of light circularly polarized (“- wavelength delay). The polarizer 98 is adjusted to pass this pattern but will cut out the plane polarized scatter light 102. Specification 982,989 is referred to.

公开(公告)号：DE1184533B

公开(公告)日：1964-12-31

申请号：DEJ0021372

申请日：1962-03-01

Applicant: IBM

Inventor： HORWITZ LAWRENCE P ,  JUN GLENMORE L SHELTON

IPC: G06F17/15 ,  G06K9/52 ,  G06K9/74 ,  G06K9/80

Abstract: 990,531. Automatic character reading. INTERNATIONAL BUSINESS MACHINES CORPORATION. May 30, 1962 [June 19, 1961], No. 20754/62. Heading G4R. In a character reading apparatus the character is scanned to derive signals representing black and white areas of the character, some or all of these signals being autocorrelated to provide a multiplicity of second signals representing at least parts of different autocorrelation orders of the character pattern and means are provided for identifying the scanned character from the second signals. A first order autocorrelation function gives the number of pairs of black areas separated by a given distance in a given direction over all possible distances and directions. The function is derived by comparing pairs of points having the same positional relationship all over the character pattern and counting all pairs where both are black. The counts may be tabulated for each positional relationship. A second order autocorrelation function comparisons are made between groups of three points and counting all triples where all three are black. The process may be repeated for any number of points in a group and the general case is considered of autocorrelation functions of first, second, and so on up to the nth order. The character 1, Fig. 1, is scanned in a horizontal raster by a C.R.T. 5 and the reflected light, received in photo-cell 7, provides signals f(t) representing the character as shown in Fig. 5. Since the speed of scanning is uniform the character may be considered as being represented by a series of fortyfive pulses i.e. a function of time. The f(t) signals are combined in pairs, triples &c. in an N-tuple generator 9 and the outputs applied to identification circuit 11. The N-tuples are extracted as shown in Figs. 28a, 28b, 28c, the photo-cell output being sampled at 45 points in the scan, to obtain the series shown in Fig. 5, and applied to a shift register 125. At each step the signals in the register stages are gated, in gates 127, with the incoming signal. This compares each position in the signal with each other position and black-black coincidences appear as output pulses which are counted by being integrated in integrators 151. The output from the 2-element combination gates are applied to further gates 129 also connected to stages of the shift-register, thereby obtaining 3- element combinations and so on. The coincidences are counted as before. The integrator outputs are D.C. voltages each representing a term in the first, second, --nth order autocorrelation functions. The first and second order functions are shown in Fig. 9 for the character "3". The first order terms are indicated along the bottom edge and again on the diagonal. Only half the table is shown since the other side is a mirror-image. The values in the table indicate the number of coincidences of the original signal train with both of points t 1 and t 2 which vary from 0 to 22. Shaded areas are points which are on the fringe of the pattern area and can be ignored. The integrator outputs after amplification at 153 are applied via resistors to certain ones of character leads SSR1-SSR0. The connections are designed so that an ideal character gives a maximum output on the corresponding lead. The lead signals are normalised for area of character by weighted resistors 157 and applied to a transistor circuit which determines the most positive signal. In this circuit each lead is connected to an N-P-N transistor with a common emitter lead. Current flows only in the transistor connected to the highest signal. The conducting transistor operates a relay and lights a lamp. In the form of Fig. 3 the integrator outputs are applied to circuits which derive "entropy" functions E1, E2, E3 (Fig. 9) which represent the "order" or "disorder" of the pattern sensed. The functions are represented by D.C. voltages and are applied through suitably weighted resistors to the character leads as before. In another form certain combinations only of the character positions are compared. These combinations may represent certain shape elements, e.g. a horizontal line. The combinations are stored on flip-flops and the outputs gated to identify the character. In another arrangement successive shape elements operate successive flipflops in recognition chains, one for each character. The first chain to be fully operated identifies the character. Seven shape elements may be specified by the combinations selected e.g. those shown in Fig. 34a. In a last embodiment the shape element signals are sampled at six instants during the scanning starting with the occurrence of the first shape element. The expected occurrences of the shape elements for the ten characters 0-9 is shown in Fig. 34c. The same pattern derived from the scanned character is entered with seven shiftregisters in similar form and gates are provided which compare particular pairs of positions in the same and different columns as the pattern is entered. Coincidences are added in an integrator and the voltages derived are compared after normalisation to obtain the highest. This identifies the character as before. Specification 982,989 is referred to.

公开(公告)号：DE1222297B

公开(公告)日：1966-08-04

申请号：DEJ0022752

申请日：1962-12-01

Applicant: IBM

Inventor： JUN GLENMORE L SHELTON

IPC: G06K9/74

Abstract: 989, 510. Automatic character reading. INTERNATIONAL BUSINESS MACHINES CORPORATION. Nov. 27, 1962 [Dec. 4, 1961], No. 44811/62. Heading G4R. In character recognition apparatus the characters are optically viewed to obtain first signals representing the character, these signals are autocorrelated to obtain second signals representing the first-order autocorrelation function, and converted into a light pattern which is compared with reference patterns the extent of the match being indicated to determine the best. An image of the character is passed over a matrix of light conductors 10A1-10An . . . 10M-10Mn Fig. la arranged in a coordinate array. Light guides 12, some of which branch, apply the light to photoconductors 14 arranged in groups 24, 26, 28 one for each of the cells in the A column Fig. 2a. The photoconductors 14A1-1, 14A2-2 &c. are connected to a source 18 so that if light falls on the corresponding matrix cell the photoconductors conduct and apply voltage to lines 30, 32, 34 &c. If light also falls on the cells corresponding to the other photoconductors of a group an output is given on one of the leads 20. The groups of photoconductors therefore act as And gates giving a signal for each position in the A column related to every other position on the matrix when both have parts of the character, Figs. 6-13. As the character moves over the sensing matrix a succession of signals are provided on the output leads 20 representing in sum the autocorrelation function of the character Fig. 14. The leads 20 are applied to long neon tubes 22 Fig. 1b which glow or not according to whether there is a voltage or not on the lead. Light from certain lamps or groups of lamps is focused by strip lenses 36. The grouping is such that signals corresponding to all the pairs of matrix positions correspondingly related are summed. The light from lenses now passes through ten filters 38 each having, for each lens an area of weighted opacity to multiply the light signal by predetermined factors. Each filter corresponds to a character, the thirteen zones being opaque in inverse proportion to the integrated light expected during scanning the corresponding character. The light transmitted through each filter 38 falls on a phosphor screen 40 which integrates it during the passage of the character and passes it to a strip photo-cell 42 which sums light outputs from the thirteen positions of the corresponding strip of the phosphor screen 40. An electrical output on lead 64 is an indication of the match between the autocorrelation pattern of the corresponding character and the autocorrelation pattern derived from the character scanned. A transistor circuit determines which lead has the higher signal and gives an error indication if two or more have signals approximating to the highest. In the form of Fig. 3 the twenty-four leads 20 are applied to Kerr cells 50 passing light or not from source 52. The filters 54 have twenty four zones and they are binary, transparent or opaque. The transmitted light from each position is summed during scanning by a phosphor screen 60 and the integrated light falls on a strip photo-cell which sums the twenty four positions to give a corresponding output. The inputs to the elements 50 may be from a shift register system as in Specification 986,276. The phosphor screens 60 may be omitted, the electric signals being summed for the same purpose. Normalising may be effected in the filters 38 of the first embodiment or alternatively by adjustable potentiometers receiving the electric outputs from the final photo-cells 42 or 62. Specification 982,989 also is referred to.