SU894750A1 - Graphic information readout device - Google Patents

Description

15) DEVICE FOR READING GRAPHIC INFORMATION

I

The invention relates to automation and computing, in particular to devices for reading graphic information for the purpose of its subsequent processing on a computer.

A device for reading graphic information is known which contains a reference generator, a key block with successively connected reversible coordinate counters, a digital-to-analog converter, output blocks and an electronic-optical block, a reversible shift register of directions, whose inputs are connected to a reference generator and electronic-optical block, and the outputs are connected to the control inputs of the key block tl.

The beam sweep directions are implemented by a key block in the form of standards. If the number of approximating directions is small, the accuracy of approximation of the lines is poor, non-. errors due to gaps and other image noise are acceptable. Moreover, with an increase in the number of directions, hardware costs grow quadratically, the design of the key block and the direction register become much more complicated. Already with discrete lines of l, the reversible shift register of directions contains the BD of output buses.

Closest to the present invention is a device comprising successively connected computing unit, digital-to-analog converters, interface blocks and an electronic-optical unit connected to the analog-to-digital converter 2.

15

A disadvantage of the known device lies in the low speed.

The purpose of the invention is to increase speed.

20

Claims (2)

The goal is achieved in that a device containing a scanning unit, whose inputs are connected to interface blocks, a computing unit connected to digital-analog converters, whose outputs are connected to the inputs of the corresponding interface blocks, and an analog-to-digital converter, has been inserted a reversible counter, connected to a scanning unit and an analog digital digit 1 m converter, and a code converter in a sequence of pulses whose inputs are connected to a reversible counter and analog digital the converter, and the output is connected to the computing unit. The drawing shows the block diagram of the device. The device contains a computing unit 1, made, for example, in the form of a digital function generator, digital-analog converters 2 and 3, blocks (and 5 interfaces (channels X and Y), scanning block 6, reversible counter 7, analog-to-digital converter 8 and converter 9 codes in a sequence of pulses. The proposed device works as follows: When a start-pulse arrives before the appearance of a stop-pulse, unit 1 begins to work out the current values of the X and Y coordinates corresponding to the radial sweep of the beam in the direction determined by the output code of the reversible counter 7. The values of X and Y are converted by digital-to-analog converters 2 and 3 and by blocks i and 5 of the conjugation and are fed to the input of block 6. The latter produces a voltage proportional to the sign and magnitude of the error between the direction of the image line and The matching misalignment voltage is supplied to the input of the analog-digital converter 8. The magnitude of the increment sign from the output of the converter 8 is supplied to the input of the reversible counter 7 and Determines the mode of operation of the counter (addition-subtraction). The absolute value of the error voltage increment through the converter 9 of the code into a sequence of pulses is fed to the input of the reversible counter 7 and, depending on the sign of the increment, is added or subtracted from its contents. The modified value of the counter 7 is fed to the input of block 1, which produces the values of X and Y corresponding to sweep the beam along the corrected direction in one cycle of its operation. The introduction of new blocks and new constructive links allows to significantly increase the speed of the proposed device as compared with the known one. Claims A device for reading graphic information comprising a scanning unit whose inputs are connected to interface blocks, a computing unit connected to digital-to-analog converters whose outputs are connected to the inputs of the corresponding interface blocks, and an analog-to-digital converter, characterized in that in order to increase the speed of the device, it contains a reversible counter connected to the scanning unit and the analog-to-digital converter, and a code converter in sequence Tel NOSTA pulses, whose inputs are connected to the down counter and analog-to-digital converter, and an output connected to a computing unit. Sources of information taken into account in the examination 1. USSR author's certificate number k7S6kO, cl. G H 11/00, 1973. 2. Patent of JARYNIA and 2933 УО, cl. 97 (7) WB2, published. 1972 (prototype).