SU729602A2 - Graphic information readout method - Google Patents

Description

The invention relates to automation and computer technology and can be used to convert and display graphic information on a computer medium or enter the coordinates of 1 points in a computer.

From the main author. St. No. 484536, a method is known for reading graphic information based on dividing the reading field into discrete 1 sections, generating an electromagnetic field in each of the sections using a sequence of interrogating pulses, the amplitude of which varies linearly and converts the electromagnetic field into an electrical control signal .

However, the disadvantage of this method is the low accuracy and speed of reading. The low accuracy is due to the impossibility of supplying a large number of interrogating pulses with a linearly increasing amplitude to the coordinate bus with a small difference in the amplitude of the previous im-2 '. pulse from the amplitude of the subsequent pulse. This is due both to the thermal noise of the coordinate bus and to the limited capacity of the digital-to-analog converters, which form a 3 · linearly increasing amplitude of the interrogating pulses.

The purpose of the invention is improving the accuracy of reading.

To do this, the amplitude of the interrogating pulse is recorded at the moment of the appearance of the first electric control signal, the electromagnetic field is re-formed in a discrete section of the reading field by the interrogating pulses of a fixed amplitude, and the amplitude of the subsequent electric control signals is determined by which the coordinate of the read point is judged.

The drawing shows a graph of the survey of the discrete section between the coordinate buses Hu and Xytl

When the bus X is interrogated by a sequence of interrogation pulses, the amplitude of which increases linearly, magnetic induction Bj is created in the discrete section.

For small secondary circuit sizes, the distribution of the amplitudes of the induced electrical control signals follows the distribution of Bj.

For a fixed value of Bj, the distance is a linear function of the polling current. Having fixed B ^ with the help of a threshold element (PE) (see the drawing), the section between the tires is divided into smaller discrete sections, each of which will be associated with a polling current pulse. 5

In contrast to the known method, determining the location of the center of the secondary circuit; combined with a point of graphic information to be read, in the area between the tires is carried out in two stages. At the first stage, the coordinate bus is interrogated by the pulses of the polling current of a linearly increasing amplitude with their simultaneous calculation until the appearance of the (first) impulse from the threshold element, i.e., 15 of the first electric control device for it:

heart rate. As a result of this, a discrete section is determined, for example, a ^ · a ^, located between the tires Xj - ^X j + 4 ·

At the second stage, the location of the center of the secondary circuit (reading element) inside the section found at the first stage of reading is specified. In this case, a series of pulses of the same fixed amplitude (25 for the section a _& —a ₄ receives current pulses with an amplitude of 1 ₄ (4) ...... enters the coordinate bus induced electrical signal ³ in the secondary circuit, respectively, in the range B ₃ —Vd The fraction of the coordinate a _m within the area determined in the first stage is determined from the measured value of Βγ ³³ Analysis of the induction amplitude is carried out by the induction analysis unit (BAI) based on the signal from the threshold element.

Thus, for example, when the distance between the tires is 10 cm, 40 and the number of pulses with a linearly increasing amplitude entering the primary circuit is 100, the spatial equivalent of each pulse will be 1 mm. If the digital block of induction analysis quantizes the electrical signal induced in the secondary circuit by another 100 levels, then the discreteness between the primary circuits (coordinate buses X · and X) equal to 0.01 mm will be obtained. ·

According to the known method, in order to obtain such discreteness. (Resolution), it would be necessary to apply a number of pulses equal to 10 ⁴ to the bus (primary circuit).

The conversion time will be maximum when the center of the secondary circuit is inside the section farthest from the X ^ bus. This time will consist of the time of supplying 99 pulses of ramp amplitude to the bus (time of the first stage) and 100 pulses of constant amplitude equal to the extracted amplitude of the 99th pulse, and in total will be equal to 199 pulses. Thus, the performance is further increased by * increasing the price of the pulse entering the primary circuit, and is achieved through the use of two-stage reading.

Claims (1)

The invention relates to automation and computer technology and can be used to convert and output graphic information to computer media or to input coordinates of points in a computer. From the main auth. Ev, No. 484536, a method of reading graphic information is known, based on breaking the reading field into discrete areas, forming an electromagnetic field at each of the sections using a sequence of polling pulses, whose amplitude changes linearly and converts the electromagnetic field into electric fields. control signal. However, a disadvantage of the known method is the low accuracy and speed of reading. The low accuracy is due to the inability to send a large number of interrogating pulses with a linearly increasing amplitude to the coordinate tire with a small difference in the amplitude of the previous pulse from the amplitude of the subsequent pulse. This is related both to the thermal noise of the coordinate bus and to the limited size of the digital-to-analog converters that form a linearly increasing amplitude of the polling pulses. The purpose of the invention is to increase the accuracy of reading. To do this, record the amplitude of the survey pulse at the time of the appearance of the first electrical control signal, re-generate the electromagnetic field in a discrete portion of the read field by interrogating pulses of a fixed amplitude, and separate the amplitude of the subsequent electrical control signals that judge the coordinate of the read point. The drawing shows a graph of polling a discrete portion between the coordinate tires Hu and X fi. When a tire is detected by a sequence of polling pulses, the amplitude of which increases linearly, magnetic induction Bj is created on the discrete portion. For small sizes of the secondary circuit, the amplitude distribution of the induced electrical control signals repeats the Bj distribution. For a fixed value Bj, distance a is a linear function of the interrogation current. By fixing Bj with the help of a threshold element (PE) (see drawing), the section between the tires is divided into smaller discrete sections, each of which will be matched with a corresponding current pulse. In contrast to the known method of determining the location of the center of the secondary contour, the graphic information to be read combined with a point in the area between the tires is carried out in two stages. At the first stage, the coordinate bus is interrogated by the pulses of the current of polling of the linearly increasing amplitude with their simultaneous counting before the appearance of the (first) pulse from the threshold element, i.e. the first electrical control and pulse. As a result, a discrete area is determined, for example, located between tires Xi. At the second stage, the location of the center of the secondary contour (reading element) inside the section found at the first reading stage is refined. At the same time, a series of pulses of the same fixed amplitude (for the current pulses with amplitude ijt (4) (k) Do the adjustment by measuring the value of the induction and the induced electric three-dimensional signal in the secondary circuit, respectively, in the range The measured value of By determines the fraction of the coordinate a within the area defined in the first stage. The induction amplitude analysis is performed by the induction analysis unit (BAI) on the signal from the threshold element. Thus, for example, when the distance between the tires is 10 cm. , and the number of pulses with a linearly increasing amplitude entering the primary circuit, equal to 100, the spatial equivalent of each pulse will be 1 mm. If the digital induction analysis unit protrudes the induced electrical current in the secondary circuit. cash by 100 levels, that is received between primary dyskret spine contours (the coordinate rails Xi and X), is 0.01 mm. According to a known method, to obtain such a discreteness (resolution), it would be necessary to feed a number of pulses to the bus (primary circuit) equal to 10. The retention time will be maximum when the center of the secondary circuit is located within the most distant from the X. site. This time will be the sum of the delivery time of 99 pulses of linearly increasing amplitude in the shiyu (time of the first stage) and 100 pulses of constant amplitude equal to the selected amplitude of the 99th pulse, and in total will be equal to 199 pulses. Thus, the speed of the increase in the price of a pulse entering the primary circuit is further increased, and is achieved through the use of a two-stage readout. The invention method of reading graphic information on the author. St. No. 484536, characterized in that, in order to increase the accuracy, the amplitude of the interrogation pulse is fixed at the moment when the first electrical control signal appears, the electromagnetic field is re-formed in the discrete portion of the read field by interrogating pulses of a fixed amplitude and the amplitude of the subsequent electrical control signals is separated, by which the coordinate of the read point is judged.