JPS589949B2 - Bar graph display method and device using CRT - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a CRT (Cathode Ray Tube).
The present invention relates to a bar graph display method and apparatus according to e), and its main purpose is to display a plurality of bar graphs on each scanning line.

When displaying bar graphs of various physical quantities and engineering quantities using a normal video CRT monitor, the CRT should be rotated at an angle of 90° to the normal direction of use (direction of use on a television receiver).
It is generally used in a rotated state, that is, with the scanning lines swinging in the vertical direction.

By the way, since a video CRT monitor has a fixed number of scanning lines (for example, a CRT used in a home television receiver has 525 scanning lines).

) The resolution when displaying a bar graph is also determined by the number of scanning lines, and to obtain higher resolution it was necessary to use a very expensive CRT with a large number of scanning lines.

For example, as shown in Figure 1, when displaying measured data of a physical quantity called waveform a in a bar graph, the number of bar graphs that display data is greater than the number of scanning lines on a CRT, so waveform a is displayed between scanning line a and mouth. Even if there is a sudden change, the change cannot be displayed because it protrudes from the CRT screen A. On the other hand, if you display the changing part A and the gap between the mouths, the display part of the changing part between C and B will be displayed. It becomes impossible.

In other words, it is not possible to display the entire image without changing the resolution.
Very inconvenient.

Furthermore, if the resolution is reduced, there is a drawback that the accuracy with which the entire image can be displayed deteriorates.

In this respect, the present invention has the advantage that when a brightness difference is added to a single scanning line, to the human eye, the line appears thick in bright areas, and the line appears thin in dark areas. The present invention aims to provide a new and advanced bar graph display method and device that can increase the resolution while keeping the number of scanning lines constant, by taking advantage of the fact that it is visually perceived as if there are multiple bar graphs. be.

Embodiments of the present invention will be described in detail below with reference to FIGS. 2 to 7.

In FIG. 2, 1 is a clock pulse generator, and 2 is a data memory that stores measurement data such as physical quantities and engineering quantities measured by a measurement section not shown. It will be done.

For example, when a RAM is used, the configuration is as shown in FIG.

In this configuration, addressing lines L10 to L1n
, If a desired address signal is added to L20-2n, the data at that address will be output to the data output lines A0-An, Bo-
Bn, and the contents stored in RAM can be read out.

However, in this case, the data contents are taken out in synchronization with the clock pulse.

And, with this, are the signals corresponding to adjacent bar graphs the same? It is taken out.

In this case, the signal corresponding to one bar graph is originally drawn on the scanning line, and the signal corresponding to the other bar graph exists between the scanning lines, which would not normally be displayed in a bar graph. It's a signal.

Next, when rewriting the contents of the RAM, the data to be rewritten is transferred to the data input line a.

In addition to -an, b'' bn, the desired address signal is sent to the addressing lines L1 0-L1n in the same way as for reading.
This is accomplished by adding a write signal to write line L3 in addition to t L2o to L2n.

Further, in FIG. 2, the numbers 3 and 4 are bar graph length generators which receive the data contents retrieved from the data memory 2 in synchronization with the clock pulses and emit a bar graph length signal according to the contents, for example. A counter is used.

In this case, the counter 3 is considered to count the measurement data corresponding to the scanning line of the CRT, and the counter 4 is considered to count the measurement data corresponding to the adjacent scanning lines.

Or you can think of it as the opposite.

Figure 4A shows an example using a normal decimal counter C,
Ao, A1, A2, and A3 are preset input terminals to which data contents are added from the data memory 2, and their respective weights are set to 1.2 and 4.8.

A when the current data content is "4".

=0, A1=O, A2=1, and A3-0 signals are preset and set in counter C by a preset signal generated from a clock pulse (see B in the same figure).

Flip-flop F/F by the preset signal
is also set.

When the counter C1 flip-flop F/F is set in this way, the gate of the gate circuit G is opened by the clock gate signal, and the clock pulse is inputted to the counter C as a counting signal to count down the set value "4". I'm going to go.

The first pulse 0 of this clock signal is 61” to tl 0
When the signal reaches 91, a zero control signal is generated which changes to "1", and this signal is applied to the AND circuit AND to open its gate.

Then, the signal "■" generated at the Q terminal of the flip-flop F/F is outputted via the AND circuit AND.

On the other hand, the contents set in counter C are count signals 0, 1,
2.3, it is counted down as "3", "2", "1", and "0", and when the count signal 4 finally reaches "9", the counter C issues BorrowOut.

Then, the flip-flop F/F is reset by this signal, and the Q terminal changes from "1" to "0".

Therefore, the AND circuit AND outputs a pulse signal of "1" for a time corresponding to the data content "4" set in the counter C as shown in FIG. 4B, that is, the length of the bar graph when displayed on a CRT. A signal equal to is obtained.

The data content A read from the data memory 2 is sent to the preset terminals of the bar graph length generators 3 and 4 using this counter, respectively.

-AngBO''-Bn and at the same time the counter starts counting, a bar graph length signal corresponding to each data content can be obtained.

Further, in FIG. 2, 5 is an adder mainly composed of, for example, an OP amplifier, which adds the output signals A and B of the bar graph length generators 3 and 4 as shown in FIG.

By this addition, the bar graph corresponding to the scanning line and the bar graph corresponding to the adjacent scanning lines are superimposed.

6 is a CRT with 525 scanning lines, which is used in home television receivers, for example, and here it is rotated 90 degrees with respect to the normal orientation so that the scanning lines swing up and down. .

Horizontal and vertical synchronizing signals generated by a synchronizing signal generator 7 are applied to the CRT 6, and the output signal of the adder 5 is also applied in synchronization with the synchronizing signals.

Therefore, each scanning line of the CRT emits light based on the sum signal obtained by superimposing two bar graphs, thereby displaying a bar graph.

As a result of this superposition, the overlapping portions of each bar graph length signal (portions P and Q in FIG. 5) are displayed brighter than the non-overlapping portions.

FIG. 6 shows this, and the thick black lines correspond to the overlapping parts.

By the way, when there is a brightness difference on a single scanning line like this, the bright parts appear thicker to the human eye, and combined with the fact that the spacing between the scanning lines is narrow, it looks like two bar graphs are being drawn. It looks like.

Therefore, in the past, it was not possible to display the entire image without changing the resolution, and it was also impossible to measure how the waveform changed between adjacent scanning lines. This is possible by displaying measurement data corresponding to the lines with a brightness difference on one scanning line.

Next, FIG. 7 shows another embodiment of the present invention in which the bar graph length signal generators 3 and 4 are constructed from analog circuits.
8 is a D/A converter that converts the data contents sent from the data memory 2 into analog quantities; 9 and 10 are analog memories that store the data contents converted into analog quantities by the D/A converter 8; 11; .12 is the analog memory 9,
This comparator compares the data content output from the clock pulse generator 10 with the clock pulse signal generated by the clock pulse generator 13.

Here, the clock pulse generator 13 is designed to generate a sawtooth wave.

Therefore, the output of the comparators 11, 12 produces a signal equal to the time it takes for the pulse signal to match the data content of the analog quantity from zero, ie, a signal corresponding to the length of the bar graph.

The adder 5, CRT 6, etc. at the next stage are the same as those in the previous embodiment, so their explanation will be omitted.

In this embodiment, the bar graph length signal generators 3 and 4 are of analog type, but as in the previous embodiment, the measurement data is
In RT6, a bar graph is displayed with a brightness difference on one scanning line, and therefore the same effect as described above is obtained.

Although only two bar graph length signal generators are used in these embodiments, it is of course possible to use three or more bar graph length signal generators.

In this way, it is possible to display a bar graph in which one scanning line is generated with a brightness difference corresponding to the amount of overlap of each bar graph length signal, and display with even higher precision and resolution can be achieved.

As described above, according to the bar graph display method and device according to the present invention, when displaying measurement data in a bar graph, a plurality of data contents are displayed by adding brightness differences on each scanning line. The resolution, which was conventionally determined primarily by the number of scanning lines, can be improved, and highly accurate measurement data can be displayed, ie, bar graphs with a greater number of lines than the number of scanning lines can be displayed.

[Brief explanation of drawings]

Fig. 1 is a diagram showing a conventional bar graph display, Fig. 2 is a block diagram showing an embodiment of the present invention, Fig. 3, Fig. 4 A,
B. FIG. 5 is a diagram explaining the detailed configuration and operation of each part shown in FIG. 2, FIG. 6 is a bar graph display according to the present invention, and FIG. 7 is a diagram showing another embodiment of the present invention. It is a block wiring diagram. 1... Clock pulse generator, 2...
Data memory, 3, 4... Bar graph length generator, 5... Adder, 6... CRT.

Claims (1)

[Claims] 1. A CRT that displays measurement data in a bar graph for each scanning line.
A bar graph display method according to the present invention is characterized in that measurement data corresponding to adjacent scanning lines is superimposed on one scanning line and displayed as a bar graph, and a difference in brightness is created between the overlapping portion and the non-overlapping portion. Bar graph display method using CRT. 2. CRT that displays measurement data as a bar graph for each scanning line.
A bar graph display device according to the present invention includes a clock pulse generator that generates clock pulses, a data memory that stores measurement data, data contents stored in the data memory are input in synchronization with the clock pulses, and a bar graph length corresponding to the contents is input. It is equipped with a plurality of bar graph length generators that generate signals of length, and an adder that adds the output signals of each bar graph length generator. The measurement data corresponding to between the scanning lines is superimposed on one scanning line and displayed as a bar graph, and the overlapping part and the non-overlapping part are displayed with a difference in brightness. CRT
bar graph display device.