SU811306A1 - Graphic information reading-out device - Google Patents

Description

one

The invention relates to automation and computing, in particular to a device for reading graphic information.

A device containing a switching circuit connected to a tablet, a generator and a control unit, a sensor (electronic pencil) connected to a frequency converter, generators of various frequencies whose outputs are connected to a synchronous detector, and switching blocks are implemented in the form of serially connected counters, decoders, modulators connected to generators of various frequencies, and transformers connected to coordinate tires of tablet 1.

The disadvantage of this device is not enough high resolution.

Closest to the invention is a device comprising a plate made in the form of a system of two mutually orthogonal buses connected to switching units connected to a control unit and to a frequency generator, connected in series by a puller, a limiting amplifier, a synchronous detector connected to a frequency generator and to time converter to code, video amplifier and null organ, code to voltage converters, adder, intermediate count counter and reversible counters, soy Inonii with the control unit, whose output is connected to the transmitter in time slot 2 code.

The purpose of the invention is to increase the resolution of the device.

This is achieved by the fact that in it the inputs of the code-to-voltage converters are connected to a frequency generator and reversible counters, and the outputs are connected to switching blocks, while

The intermediate count counter is connected to the null organ, to the control unit and to one input of the adder, the other input of which is connected to the time interval into code converter, and the output is connected to the output of the device.

The drawing shows the block diagram of the device.

The device contains planchet 1, switching blocks 2 and 3, the frequency generator 4,

transducer 5 for time interval into code, control unit 6, synchronous detector 7, coordinate remover 8, limiter amplifier 9, blocks 10 and AND code to voltage, for example, alternating

current, reversible counters 12, the amplifier 13, the zero-body 14, the counter of intermediate counts 15 and the adder 16.

The device works as follows.

At first, the control unit 6 starts the switching unit of 2 axis X buses, supplying pulses to the coordinate buses through the group transformers of block 2. Simultaneously with the start of switching, the counter of the converter group number 5 is opened. The coordinate remover 8, which is in the zone of one of the groups, receives the signal amplified by the limiting amplifier 9 and fixing the group number code on the counter 5 of the converter.

Then the control unit 6 starts the bus switching. The initial installation of one higher bit of counters 12 into a single state opens one key each in blocks 10 and 11, supplying a sinusoidal carrier voltage of a certain level to the modulators of block 2, providing pulses to the first, second, etc. buses of all groups . The signal received from the selectable bus fixes the code of the bus number on another counter of converter 5.

The coarse coordinate code (up to the quantization step) is formed from the code dialed on the group counter (most significant bits) and the code on the tire meter (least significant bits).

Then the control unit 6 sets the bits of the counters 12 to the initial state and opens all the modulators of the block 2. The paraphase outputs of the blocks 10 and I are fed to the modulators so that in the initial state the first amplitude and phase signals are fed to the first buses 180 ° , on the second tires - the signal of maximum amplitude and phase 0 °, on the third spinnas - the signal of zero amplitude. Further, the control unit 6, changing the state of the meters 12 synchronously (added to one of the meters and subtracted from the other by one pulse), changes the voltage level on the tires: on the first tires, it decreases to zero; on second tires it increases with an initial phase of 180 °, and on third tires it increases with phase 0 °. At the same time, at each state of the counters 12, the counting pulse is added to the counter of the intermediate counts 15.

A wavy alternating electric field is formed in the plane of the location of the coordinate tires, the period of which is equal to four quantization steps. Depending on the voltage applied to the tires at a certain point in between, the field potential is zero, and the oscillation phase varies from 0 ° by 180 or from 180 ° by 0 °. When the states of the counters 12 change, the point of zero potential moves within the quantization step. Since there is no link with a pencil in zone A of this point (regardless of the distance of the pencil from the tires), the null organ 14 issues a signal when the amplitude of the received signal passes through zero and fixes on the counter 15 the binary value and the sign of the correction. This value is set to adder 16 to sum with the coarse value nodavayem

into block 16 from converter 5, and obtaining at the output of the adder the code of the exact value of the coordinate X.

After completing the formation of the exact code of the X coordinate, the control unit 6

runs a similar loop on the y axis.

The introduction of new constructive relationships has significantly increased the resolution of the device.

Claims (2)

1. USSR author's certificate number 483683, cl. G 06K 11/00, 1969. 2. The patent of England No. 1325493, cl. G 4H, publ. 1973 (prototype).