SU807348A1 - Symbol reading-out device - Google Patents

Description

This invention relates to technical | : oh cybernetics, in particular, to methods of reading characters, and can be used when entering information into a computer. There is a known method of reading characters based on line-by-line scanning of the reading field, generating read signals and converting them into a sequence of characteristic features that judge the readable characters 1J. However, this method has., Not enough high reliability. The closest technical solution is a method based on an increase in the luminous flux by successively changing the illuminated part of the readout field, transforming the luminous flux into an electrical signal, shaping the unwrap signal of the symbol and its spectral spectrum 2. The disadvantage of this method is low read speed. The purpose of the invention is to increase the speed of reading the characters. The goal is achieved by simultaneously creating a read reference signal with a sequential change in the illuminated portion of the readout field, inverting and summing its amplitude with the amplitude of the symbol-sweep signal, and judging the result of the spectral analysis of the received signal detects the read symbol. The amplitude of the read reference signal is generated by pu-. By continuously increasing the voltage from zero to the amplitude value of the sweep signal for the duration of the change in the luminous flux and then abruptly decreasing the voltage to zero. FIG. 1 shows the formation of a winder signal; in fig. 2 shows the block diagram of the device in FIG. 3 is a timing diagram for the conversion of the scanning sweep using a read reference signal. The device for implementing the method contains a field of 1 symbol, a symbol 2, illuminated with 3 characters, an unlit field of 4 symbols and a time pattern of forming a scanning sweep, a block 6 of forming a reference pulse 6, an adder 7, a spectrum analyzer 8, a block 9 of control and a photometric instrument 10, a turn-off sweep signal 11, inverted reference wall 12 (read pulse.

According to the proposed method, the luminous flux is increased by continuously changing the portion of the reading field illuminated by the beam from zero to the full area of that field. FIG. 1a and 1e, field 1 of a readable symbol 2 is shown at successive times with different sizes of the illuminated (non-hatched) part of the floor 3 and the unlit (hatched) part of the floor 4. The magnification of the illuminated part shown here can be done in various ways, for example by moving the screen, shaded of the fully illuminated character field.

At the same time, at the output of the photometric instrument 10 a sweep signal is generated, shown in FIG. 1g. The peculiarity of this signal is the continuous (without breaks) voltage rise from zero to the amplitude value, which remains unchanged at the end of the scan.

At the subsequent stages of the proposed method, a read reference signal is formed and with its help the received scanning signal is converted into a continuous pulse. Such a conversion means that instead of a sweep signal, a continuous pulse is obtained while maintaining the zero initial value of the transformed signal.

In the sweep signal (Fig. 1g), the information about the readable symbol is embedded in the rising edge of this signal, therefore the said conversion of the sweep signal into a pulse must be done so that the leading edge of the received pulse is associated with a certain functional dependence on the leading edge of the sweep signal.

The conversion of the sweep signal into a pulse satisfying the agreed conditions is carried out by turning off the sweep signal at the end of scanning and subtracting from the received signal a reference pulse that has a leading edge that increases during the time of the light flux from zero to the amplitude value of the signal sweep with a finite constant or continuously varying speed and a falling front abruptly decreasing to zero.

Such a conversion can be carried out using a device whose block diagram is shown in FIG. 2. The signal to be scanned from the output of the photometric instrument 10 is supplied to the input of the adder 7, to the second input of which the inverted pulse from the block 6 is supplied.

The operation of block 6 controls the control unit, kg torg) also pt; the bench press changes the part of the poly readout. At the moment of the start of scanning, under the action of the control signal from block 9 in block b, the leading edge of the reference pulse, which is continuously stretching from zero, begins to form. At the time of the end of the scan, under the action of the control signal from block 9, the formation of the rising leading edge is stopped and the voltage of the reference pulse abruptly decreases to zero (Fig. 3b). The resulting reference pulse has an amplitude different from the amplitude of the sweep signal, as shown by dotted lines fig.Zb. Therefore, block b should contain a comparison circuit to which the reference pulse and the scan signal from instrument 10 (Fig. 2) are supplied. By comparing their amplitudes, the amplitude of the reference pulse is equalized to the amplitude value of the sweep signal, after which this negative polarity pulse (Fig. 3b) is supplied to the adder 7. At the same time, the sweep signal is also turned off by the signal from block 9 photometric device 10 or lock it vg, 1khoda on the adder 7 (Fig. 2). In this case, instead of the sweep signal (Fig. 1g), a switchable signal (Fig. 3a) is obtained, which is supplied to the adder 7 (Fig. 2). The timing diagram (Fig. 3g) shows on an enlarged scale a bipolar pulse, which is received in adder 7 and is supplied to an AJ by analyzing 8 spectra (Fig. 2).

The final operation of the proposed method is the spectral analysis of the pulse obtained as a result of the conversion of the sweep signal described.

The introduction of a new sequence of operations has significantly increased the speed of reading characters.

Claims (2)

1. A method of reading symbols based on increasing the luminous flux by successively changing the illuminated portion of the readout field, converting the light flux into an electrical signal, generating a symbol sweep signal and its spectral analysis, characterized in that, in order to improve the speed of reading the symbols, simultaneously with by changing the illumination 1:) th part of the readout field, form a C) ggi11N.1th readout signal, invert and cyf.iMnpyiiiT its amplitude from the amplitudes of the up to the signal of the pc13 convolutions of the symbol and the result of the spectral analysis of the received signal is judged on the read symbol, 2. Sposo (3 POP.1, characterized in that the amplitude formation of the read reference signal is carried out by continuously increasing the voltage from zero to the amplitude value of the sweep signal during the change in the light flux and then abruptly decreasing the voltage to zero. Sources of information taken into account in the examination 1. Patent STR. 3980990, cl. 340-149, 1976. 2. USSR author's certificate for application number 2537234 / 18-24, cl. G 06 K 9/00, 10/27/77. .. (, .. 2 4  V u t sh . t - tn B f ti tj ii. if .2 Urn And | / H  tf / n / 4 t F (". 3