JPH0659885U - Display deterioration prevention device - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent the deterioration of the display device. A chaotic signal generator 10 for generating a chaotic signal and a signal converter 20 for inputting the chaotic signal to generate a display signal for a display device.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a display deterioration preventing device that generates a display signal for preventing deterioration of a display screen of a display device such as a CRT display device.

[0002]

[Prior art]

 When the CRT display device is not used in the operating state, if a still image is displayed on the CRT screen for a long time, a specific part of the phosphor on the CRT screen deteriorates, causing a so-called burning phenomenon. When a normal moving image is displayed, that portion appears as a shadow, which significantly deteriorates the image quality.

Therefore, conventionally, a specific display pattern is prepared, and pattern deformation such as vertical movement, horizontal movement, rotation, and enlargement / reduction is added to the specific display pattern so that the specific pattern does not stand still on the CRT screen. For such pattern changes that occur over time, a program for the changes was prepared in advance.

[0004]

[Problems to be solved by the device]

 However, if the pattern is made complicated and the reproducibility is lost and the effect of preventing CRT burning is to be improved, a more complicated program is required, and the memory of the computer that is idle is used a lot, resulting in a large memory capacity. There is a problem of causing a shortage of.

An object of the present invention is to enable generation of a signal for displaying a chaotically changing pattern without the need to create a program for preventing deterioration as described above, and prevent deterioration of the display device. It is to provide a prevention device.

[0006]

[Means for Solving the Problems]

 To this end, the present invention comprises a chaotic signal generator for generating a chaotic signal and a signal converter for inputting the chaotic signal to generate a display signal for a display device.

[0007]

【Example】

Embodiments of the present invention will be described below. FIG. 1 is a diagram showing a block of the configuration of the embodiment, in which 10 is a chaotic signal generating device, and 20 is input two chaotic signals x _n and y _n generated by the chaotic signal generating device 10. Then, the CRT display device 30 is a signal conversion device for converting it into a signal for display. The chaotic signal generation device 10 and the signal conversion device 20 constitute a display deterioration prevention device (a portion surrounded by a broken line).

FIG. 2 is a block diagram showing the configuration of the chaotic signal generator 10. The device 10 includes delay circuits 11 and 12, initialization circuits 13 and 14, a non-linear function circuit 15, a coefficient multiplication circuit 16, and an addition circuit 17. A clock signal φ having a period of Δt is given to each of the delay circuits 11 and 12, the non-linear function circuit 15, the coefficient multiplying circuit 16, and the adding circuit 17 among them, and the clock signal φ is synchronized with this clock signal φ. Delay, function operation, multiplication, and addition are performed.

The delay circuits 11 and 12 delay the input signal by one clock cycle (Δt) and then output the delayed signal. Further, the initialization circuits 13 and 14 are represented by a symbol as shown in FIG. 3 (A), but are specifically realized by the changeover switch shown in FIG. 3 (B).

In this changeover switch, when the initial value x ₀ or y ₀ is given, the terminal T _B is connected to the terminal T _C , and the initial value input to the input terminal C is transmitted to the output terminal B. In the subsequent operation, the terminal T _B is connected to the terminal T _A , and the signal input to the input terminal A is transmitted to the output terminal B.

The non-linear function circuit 15 outputs a non-linear function f (x _n ) of the input x _n . The coefficient multiplication circuit 16 multiplies the input y _n (= x _n-1 ) by the coefficient a and outputs the result. The adder circuit 17 calculates the sum of all its inputs and outputs the addition result as x _{n + 1} to the delay circuit 11.

Now, the chaotic signal generator 10 shown in FIG. 2 operates as follows. When the initial values x ₀ and y ₀ are added from the initialization circuits 13 and 14, the initial value x ₀ is given to the nonlinear function circuit 15 and the delay circuit 12, and the initial value y ₀ is given to the coefficient multiplication circuit 16 2. Therefore, the non-linear function circuit 15 outputs a signal of f (x ₀ ), and the coefficient multiplication circuit 16 outputs a signal of a · y ₀ . Therefore, the adder circuit 17 outputs the signal x ₁ represented by x ₁ = f (x ₀ ) + a · y ₀ (1). This signal x ₁ is input to the delay circuit 11. Then, when one clock period Δt elapses, the signal x1 is output from the delay circuit 11 and the signal x ₀ (= y ₁ ) is output from the delay circuit 12.

In this manner, the delay circuits 11 and 12 output x _n and x _n-1 (= y _n ) respectively at a certain point of time, and the nonlinear function circuit 15, the coefficient multiplication circuit 16 and the addition circuit 17 The calculation of the equation (1) is performed, the signal x _{n + 1} is output from the adder circuit 17, and this is given to the delay circuit 11, and the repetitive operation is performed every Δt. Thus, the signals x _n and y _n appear at the output terminals of the delay circuits 11 and 12, and these are taken out from the output sides of the initialization circuits 13 and 14 as chaotic signals.

When the chaotic signal is generalized, x _{n + 1} = f (x _n ) + a · y _n (2) y _{n + 1} = x _n (3) Here, if the nonlinear function f (x _n ) is represented by the following equation, then f (x _n ) = b · x + (x + cos x ² ) / (1 + x ² ) (4) This function f (x _n ) is Draw the curve shown in FIG. b is a parameter, and b = 0.300.

FIG. 5 shows the points represented by the signals x _n and y _n obtained from the above equations (2) to (4) on the XY coordinates, where n = 1 to 2000, that is, the initial value. All of the 2001 points appear, including (x ₀ , y ₀ ). Here, a pattern obtained when the conditions of initial values x ₀ = 0.000, y ₀ = 0.000, parameters a = −1.000, and b = 0.300 are set are shown.

As described above, by using the non-linear function f (x _n ), the pattern displayed two-dimensionally by the obtained chaotic signals x _n and y _n becomes a chaotic pattern that constantly and unexpectedly changes. . In the present embodiment, the pattern obtained by such a chaotic signal is displayed on the CRT display device 30 to prevent image sticking.

[0017] However, the chaotic signal x _n, since it is difficult to enter y _n as the CRT display device 30, the chaotic signal x _n, the display of the CRT display device 30 in the signal conversion device 20 y _n The conversion process is performed so that it is suitable for the signal involved.

Here, a horizontal sweep signal HD is created by one chaotic signal x _n , a vertical sweep signal VD is created by the other chaotic signal y _{n, and} a luminance signal Y (DC signal) of a constant level is further created. Then, these are input to the CRT display device 30 as a pattern display signal for preventing image sticking.

Therefore, the CRT display device 30 takes in the horizontal sweep signal HD in place of the horizontal sync signal, the vertical sweep signal VD in place of the vertical sync signal, and the luminance signal Y in place of the display luminance signal. Take in. Therefore, the CRT display device 30 performs a vector scan to display an irregular and unexpected chaotic pattern. The pattern at this time is a pattern drawn by one line (for example, a display screen of an oscilloscope).

In other words, instead of the pattern shown in FIG. 5 in which the points determined by the chaotic signals x _n and y _n obtained from the initial stage to the present are accumulated, the time of the clock Δ t of the chaotic signal generator 10 and the CRT The pattern is displayed according to the operation delay of the phosphor on the screen. Since the display amount per unit time increases as the frequency of the clock Δt increases, a complicated pattern is drawn.

Since the CRT display device 30 needs to perform a raster scan when displaying a normal image, a normal image input unit (raster scan input unit) of the NTSC system or the like and the signal conversion device described above. It is necessary to switch from the input part of the chaotic pattern signal from 20 by operation, but this switching part is omitted.

The signal processing device 20 not only creates a signal for vector scanning, but also takes in chaotic signals x _n and y _n and uses them as a luminance signal Y for raster scanning or an RGB color signal. It is also possible to convert the input into the CRT display device 10 as a normal display signal.

For example, when converting to the luminance signal Y, one signal Y may be obtained by processing the chaotic signals x _n and y _n with a predetermined function (which may be linear or non-linear). That is, it suffices to perform the processing of Y = Fa (x _n , y _n ). Further, when converting to RGB signals, different functions for R, G, and B may be set and processed with these to obtain three signals. That is, R = Fr (x _n , y _n ), G = Fg (x _n , y _n ), and B = Fb (x _n , y _n ) may be processed. The latter gives a particularly fantastic color pattern.

Further, in the above embodiment, only two signals x _n and y _n are extracted from the chaos generator 10, but only one may be extracted, and an output signal of an arbitrary circuit portion can be extracted. Therefore, three or more signals may be taken out and the signal conversion device 20 may create a signal for a chaotic pattern. In addition, the chaotic signal generator 10 uses a delay circuit of 3 or more, an initialization circuit of 3 or more, a non-linear function circuit of 2 or more, and a coefficient multiplication circuit of 2 or more to generate a more complex chaotic signal. Can be generated.

Further, although the above-mentioned embodiment is the device for preventing the burn-in of the CRT display device, the same part is similarly fixed even when applied to the display device using other LCD, LED, plasma and the like. It is possible to prevent the deterioration due to the display drive.

[0026]

[Effect of device]

 As described above, according to the display deterioration preventing apparatus of the present invention, since the display pattern is created by the chaotic signal, the display pattern can be changed without predictability, and the same part of the display device is deteriorated by the display drive. Can be effectively and easily prevented.

Further, since this display pattern uses the signal generated by the chaotic signal generator regardless of the computer cooperating with the display device used, the memory capacity of the computer can be secured without wasting the memory of the computer. To contribute.

Further, this display pattern is fantastic and there is a feeling of waiting that the next pattern will be unpredictable. Therefore, displaying this when the work using the display device is stopped helps the comfort.

[Brief description of drawings]

FIG. 1 is a block diagram of a display deterioration prevention device and a CRT display device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a functional configuration of a chaos signal generator.

FIG. 3A is a symbol of an initialization element, and FIG.
[Fig. 3] is a diagram showing respective concrete circuit examples thereof.

FIG. 4 is a characteristic diagram of an example non-linear function.

FIG. 5 is an explanatory diagram of a chaotic pattern using a signal from a chaos signal generator.

[Explanation of symbols]

10: chaotic signal generator, 20: signal conversion circuit, 3
0: CRT display device, 11, 12: delay circuit, 13, 1
4: initialization circuit, 15: non-linear function circuit, 16: coefficient multiplication circuit, 17: addition circuit.

Claims (1)

[Scope of utility model registration request] 1. A display deterioration preventing apparatus comprising: a chaotic signal generating apparatus for generating a chaotic signal; and a signal conversion apparatus for inputting the chaotic signal to generate a display signal for a display apparatus.