SU1675934A1 - Data display unit - Google Patents

Abstract

The invention relates to electronic engineering and can be used in devices for displaying information on gas discharge matrix display panels. The purpose of the invention is to improve the quality of the display by increasing the contrast. To achieve the purpose of the invention, a device comprising a gas-discharge matrix display panel 1, blocks 2 and 3 of anode and cathode keys, a decoder, a counter of 5 columns, a block 6 of comparison, a counter of 7 cycles, a clock input 12, an output 11 and information input 11), 8 frequency divider and 9 code converter are entered. The device increases the image contrast by eliminating the moving grid, creating background illumination, and stable image formation is achieved due to a significant increase in the turn-on duration of one of the indicator columns at the same time with a slight decrease in the turn-on time of all the other columns. 3 il. with SS (L

Description

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The invention relates to electronic engineering and can be used in devices for displaying information on gas discharge matrix display panels.

The purpose of the invention is to improve the quality of the display by increasing the contrast.

Figure 1 shows the structural diagram of the proposed device; figure 2 is an example implementation of a frequency divider; on fig.Z - timing charts work frequency divider.

The device contains a gas-discharge indicator panel 1, blocks 2 and 3 of anode and cathode keys, decoder 4, counter 5 columns, block 6 of comparison, counter 7 cycles, frequency divider 8, converter 9 codes 3 information input 10 output 11 and clock input 12 . The frequency divider 8 contains a waiting one-shot O and the element And 14.

The device works as follows.

For reliable ignition of display elements in the device with unchanged image scan time, the excitation time of the columns is redistributed so that during each scan cycle the excitation time of one column increases significantly (several times) and the excitation time of the remaining columns slightly (by several percent) decreases. . .h

Assume that the output codes of the counter 5 columns and the converter of the 9 codes do not match and the output signal of the comparison unit 6 is zero. The clock pulses from input 12 are fed to the input of a 5 column counter, the contents of which change by one with the arrival of each pulse. The output code of the counter, 5 columns, arriving at the decoder 4, provides alternately. switching on the cathode keys of the block 3, which produce high-voltage pulses for controlling the vertical busbars (cathodes) of the gas-discharge matrix display panel 1. With this code O ... PP meter 5 corresponds to the supply of control pads to the first cathode of panel 1, code, 00 ... 1 - to the second cathode, etc. The information input of the block 2 of the anode switches from the input 10 synchronously with the clock pulses at the output 11 of the device, in accordance with the displayed information, receives control signals.

If in the current sweep cycle the output code of the converter of 9 codes is O .... Software, then when the counter 5 is switched to the state 0 ... 00, i.e. When the first column of panel 1 is connected, a coincidence signal is generated at the output of block 6 of the comparison. The output signal of the comparator unit 6 is supplied to a frequency divider 8, which operates as follows. If the control input of the frequency divider 8 has a zero signal, then the clock pulses pass from the clock input of the converter to its output without any changes, i.e. the frequency of the input pulses does not change. If a single signal appears at the control input, then the clock pulse passes through divider 8 for some time known in advance, which is equivalent to reducing the frequency of the clock pulses. In the frequency divider 8 depicted in FIG. 3, when a single signal appears on the control input, a waiting single vibrator 13 is allowed which generates a zero signal of a predetermined duration at its output that prohibits the passage of clock pulses through the And 14 pulse. After a predetermined time has passed at the single vibrator output 13 a single signal appears again, allowing the passage of clock pulses through AND 14 without any changes.

Consequently, for some time equal to the duration of the zero signal at the output of the one-shot 13, the counter 5 is in the same state and all this time the necessary elements of the first column are excited (Fig. 2). At the end of this time, the clock pulses from input 12 to frequency divider 8 are resolved again, so the 5 column counter increases its content and the second, third and other columns of the indicator are connected sequentially with a period of clock pulses. After the last column is sampled, the count of my 7 cycles increases by one. As a result, at the output of comparator block 6, a signal appears: during the connection of another column,

converter 9 defined by the output code, and, therefore, the connection time of this column is significantly increased (Fig. 2). In the next sweep cycle, the connection time for one more column is increased, etc.

Thus, in the proposed device, in each sweep cycle, the connection time of one of the columns is significantly increased while the connection time of the others is not significantly reduced. Obviously, in each cycle, the probability of ignition of the display elements of one of the columns increases accordingly, with a slight decrease in the probability of ignition of the others. In the following image sweep cycles, the connection time of one of the following columns increases with a slight change in the connection duration of the others, therefore, in the proposed device, during the entire period of changing the state of counter 7, a one-time significant increase in the ignition probability of all display elements involved in image synthesis occurs. Since the connection period of the elements (sweep) is shorter than the time for restoring the electrical strength of the occurrence of a discharge, reliable image reproduction occurs after at least one ignition of the element, and in contrast to the known device this is achieved without using background illumination and reducing the contrast of the moving grid image.

Let us compare the characteristics of the proposed device and the one known in the following example. Let the information be reproduced on the IGP-6A 6 + M indicator panel (3.397. PS), and the sweep period ensuring the maintenance of burning lighted elements is 1000 x. Then the duration of 1 column connection in the known device is 15.63 microns. If the duration of the connection of one of the cathodes compared with the rest is three times longer, then the duration is t (the connection of this cathode is 5.5 µs, and the duration of connection of the others is 15.15 µs, that is, with an increase in the duration of the connection of one of the cathodes three times the duration

connecting the rest is reduced by only 3. Since the excitation of the display element for tens of microseconds, the probability of initial ignition is directly proportional to the duration of the connection, the probability of igniting the elements of one of the columns in each sweep cycle increases threefold. If the full cycle of imaging in the device stacks up in the period T

Chr determined by the critical frequency of flickering f

cr,

that

the total connection time of all elements is the same, and the luminance of the formed image does not change.

If the full cycle of imaging is longer. It is necessary to determine the brightness of the image formed during the TCR. Since the brightness of the generated images is completely determined by the duration of burning, and consequently, the connection of elements, we determine the total duration of the excitation of elements.

Let in time T be L connections of all columns. Then

the brightness of the element's flashlight if it has been excited during one of the sweep periods for a longer sweep time period is proportional to

35

B.K, + (L - 1) and,

the brightness of comrade

glow of the remaining elements

B2-Lfc,

Under those jHe conditions, the brightness of the element in a known device is proportional to

BUS6-Lt,

Since in practice L 1 and, the values of B, B and B differ slightly.

If L 40, i.e. critical frequency of 25 Hz, then for the considered example

In А-3-15.15 +, 15 635.3 μs; In-15.15NO 606.0 μs,

 4015.63 625.2 μs.

Thus, the luminance brightness of an element, if it is excited during one of the sweep periods during a longer sweep time, differs by less than 5% from the brightness of the others.

Due to the fact that the threshold value for visibility of differences in effective brightness, proportional to the long-term burning of elements in two adjacent periods of image scanning, with a critical flashing frequency is much higher, the operator does not notice these changes in brightness. In addition, since the sweep period of the image can be significantly shorter than T (Φ, the differential threshold of sensitivity to change in luminance ei, 2 is higher. If it is necessary to significantly increase the excitation duration of one of the columns in each sweep period, then to increase L () column or pseudo-random sweep. For this, the device uses a code converter 9, which by output counters 7 forms the required sequence of choice of vertical tires, the duration od exception which must be increased in each period of the scanning. Rather transducer 9 codes can be used about the changed circuit by the order of connecting the counter 7 outputs to the inputs of the comparing unit 6.

Thus, the proposed device provides reliable image reproduction at

five

about

0

five

five

But the luminance brightness of the elements is less than 5 A for known devices, the achievable ratio of the image brightness and background illumination brightness does not exceed 10: 1. In addition, the periodic ignition of all the elements of the indicator when creating a moving grid increases power consumption and reduces the reliability of known devices.

Claims (1)

Invention Formula A device for displaying information, containing a serially connected column counter and a cycle counter, another output of the column counter is connected to the first input of the comparison unit and the decoder, the output of which is connected to the input of the cathode key unit, the output of which is connected to the vertical buses of the gas discharge display panel, which horizontal tires connected to the output of the anode key block, whose input is the information input of the device, characterized in that, in order to improve the quality of the display for an increase in contrast, a frequency divider and a code converter, the input of which is connected to the output of the cycle counter, are entered into it, and the output is connected to the second input of the comparator, the output of which is connected to the control input of the frequency divider, the clock input and the output of which is a clock input and code device, respectively. Ha Qenfy.6 L Phage.1 II i-th Kudo tt +) - U ka $ o Fig.Z