JPS5989093A - Display device of color picture with thin thickness - Google Patents

Abstract

PURPOSE:To reproduce the picture of a high color saturation degree by circulating three times the storage contents delivered in parallel from the 1st line memory in the form of a serial output/serial input and displaying said contents on a CRT after reading them in a writing speed triple as high as the 1st line memory. CONSTITUTION:The video signal supplied to a terminal 15 is fed in series to the 1st line memory 16 which stores the signal information of a 1H period formed by a CCD. Then this stored information is delivered in parallel to the 2nd line memory 17. The reading speed of the memory 17 is set at a level triple as high as the writing speed of the memory 16. The read-out information is supplied again to the memory 17 via a feedback loop 18. This information is written twice, and the video signal impressed to the terminal 15 is compressed down to 1/3 in terms of time to be delivered three times to the output terminal of the memory 17. This output is supplied to a signal processing circuit 19. The circuit 19 reproduces only red, green and blue chrominance signals at the 1st, 2nd and 3rd times respectively. These reproduced chrominance signals are sent to a thin color CRT20 and displayed on the screen.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an image display device using a thin color cathode ray tube.

[Prior art]

An image display device using a rectangular color cathode ray tube based on the monochrome tube structure shown in FIG. 1 has already been proposed. FIG. 1(A) is a front view, and FIG. 1(B) is a side sectional view. An electron gun 2 is attached to the neck of the knob 1 of the cathode ray tube, and the electron beam 3 emitted from the electron gun is shown in Figure (A).
) is deflected by a deflection coil 4 in the same way as in the case of a normal television picture tube. This X and Y deflection can also be performed by electrostatic deflection. The electron beam 6 that has exited the X and Y deflection areas is deflected in the Z direction due to the potential difference applied between the side surfaces 56 of the thin pulp 1, and strikes the 11I+1 layer 5 coated with a fluorescent material, causing a fluorophore. Make a light body emit light. The image displayed on the cathode ray tube can be viewed from the side 5.
It is also possible to view the reproduced image from the side surface 6 by constructing the trench side surface 6 with a transparent conductive film and applying a voltage between it and the side surface 5.

The following methods are conceivable for displaying a color image on an image display device using the above-mentioned thin-type image forming apparatus, but each method is difficult for the reasons explained below.

If you try to use the shadow mask method, the electron beam must be deflected in three directions: It is extremely difficult to design a coating structure and a shadow mask for the fluorescent surface and the luminescent surface, which can be expected to achieve good beam running.

Next, in order to use the index method, it is necessary to collect an optical index signal during scanning, but with a thin cathode ray tube,
The distance from the electron gun to each part of the phosphor surface varies greatly depending on the position on the phosphor surface, resulting in large deflection defocus, and the electron beam is obliquely incident on the phosphor surface, which degrades focus. It is extremely difficult to obtain an original index signal of 4&i over the entire screen. In the index method, an index signal cannot be obtained unless a sufficiently fine electron beam is obtained over the entire effective screen, and since there is no color selector such as a shadow mask, the radiation and blue phosphors emit light at the same time. , Colorful o[''
Unable to reproduce high-quality color images.

In addition to the above, a plasma display panel is used as a means for realizing a thin color image display device.

Electroluminescent (EL) panels, fluorescent display tube panels, etc. are conceivable, but these all have drawbacks in terms of efficiency, cost, natural color reproduction, etc. compared to display devices using cathode ray tubes. .

In order to solve the above problem, red, green, and blue phosphors were arranged in vertical stripes, and each phosphor stripe was electrically separated, as shown in Figure 2, which shows an enlarged view of the phosphor surface structure. A thin cathode ray tube device for displaying a color image is conceivable, in which the phosphor stripes of the same color are electrically bundled together and an applied voltage supply terminal is provided outside the cathode ray tube. In Figure 2, RG and B are respectively ζ, green, green and blue phosphor stripes, 7,
Terminals 8 and 9 are for supplying voltages to be applied to the red, green and blue phosphor stripes outside the cathode ray tube, respectively. Even if the diameter of the electron beam spot 10 covers a plurality of phosphor stripes as shown, for example, the terminals 7 and 9 may
1. By applying pressure and applying a high voltage to the terminal 8, only the green phosphor can be caused to emit light. However, when the fluorescent material is applied in vertical stripes, it is necessary to switch the voltage application to the terminals 7, 8, and 9 extremely rapidly in order to switch colors between red, green, and blue. For example, to obtain a sufficiently high horizontal resolution, the number of R, G, and B color phosphor sets is 20.
If a set of 0 is provided and this is scanned with an electron beam in one horizontal scanning period (approximately 50 μs), it is necessary to switch the voltage applied to terminals 7 and 8.9 with a response width of 80 nS. The positive amplitude required for terminals 7, 8, and 9 in order to change J requires at least several hundreds of square meters due to the beam spot diameter and other conditions, but it is necessary to switch the voltage of several hundred squares at about 80118. It is extremely difficult to implement the system shown in FIG. 2 because suitable switching elements are not available. Even if a suitable switching element could be obtained, this method requires a large amount of power to drive the stray capacitance between the color phosphor stripes at a high frequency, and a simple calculation shows that the amount of power required is around 10 W or more. [Object of the Invention] An object of the present invention is to solve the above-mentioned drawbacks of the prior art and to provide a color image display device using a thin color cathode ray tube. .

[Summary of the invention]

In order to achieve the above object, in the present invention, red, green, and blue phosphors are coated in a horizontal direction substantially parallel to the electron beam scanning to form horizontal stripes, and the phosphor stripes of the same color are connected to each other. We use thin color cathode ray tubes connected to color selection voltage application terminals outside the tube, and one line memory
The video information during the horizontal period is stored, and this memorization/ζ information is repeated 6 times at a speed 6 times faster than the scenting process. It demodulated, and in synchronization with this demodulation, the voltage applied to the color selection voltage application terminal outside the cathode ray tube was switched, so that horizontal stripes of six primary colors were scanned within one horizontal period at a speed of 6 times IW. .

Furthermore, reading out this red, green, and blue information 11. [By changing the i1 order cyclically and sequentially, it is possible to prevent deterioration of vertical resolution even if the number of horizontal phosphor stripes is small. In addition, by using horizontal stripes, the number of times the voltage applied to the color selection voltage application terminal is changed is greatly reduced.
Existing switching elements are sufficient for switching - [Embodiment of the invention] Fig. 5 is a partially enlarged structural diagram of the fluorescent surface of the thin color cathode ray tube according to the present invention, where R, G, and B are red, respectively. , green, and blue phosphors. These stripes are coated on mutually insulated horizontal strip electrodes (transparent electrodes when viewed from side 5 in Figure 1), and are coated with phosphors of the same color. The stripe electrodes are connected to each other, bundled, and led out to color selection voltage application terminals 11, 12, and 13 outside the tube. For thin cathode ray tubes, '5A, (tel.
1 beam spot diameter could not be obtained, beam spot 14
will cover the multicolor phosphor stripes as shown. However, if, for example, a low voltage is applied to terminals 11 and 13 and a high voltage is applied only to terminal 12, high-speed, high-energy electrons will strike only the green phosphor stripe, causing the green phosphor stripe to Only the light emits light. In addition, if there is a difference in the %i pressure applied to the stripes like this, an electrostatic lens is formed near the fluorescent surface, and the electrons that initially went toward the R and B stripes are also
The electron beam can be bent in the stripe direction, and the electron beam utilization efficiency is higher than that of the beam index method as well as the shadow mask method. The intensity of the light emitted by the phosphor stripes is controlled by controlling the amount of electron beam applied to the cathode or first grid of a color signal lamina gun.

FIG. 4 is a block diagram of a signal processing circuit according to the first embodiment of the present invention. The received video signal is applied to the terminal 15, and is serially input to a first line memory 16 that stores 1st signal information for one horizontal period, which is composed of a CCD, etc., and the stored information is sent to a second line memory 17. Output is done in parallel. i.e. #! The first line memory converts information from serial to parallel in time.The second line memory serially outputs the information input in parallel and converts it from parallel to serial in time. 6 times the writing speed to line memory, and the read information is fed back to feedback loop 1B
The same information is input to the second line memory again through the process, and the same information is rewritten twice to the second line memory.
The video signal applied to the terminal 15 is temporally compressed to 1/6 and output to the output terminal of the line memory 17 three times. This output is input to a signal processing circuit 19 having basically the same configuration as the color signal and brightness +=<= processing circuit of a normal color television receiver. However, the signal processing circuit 19 reproduces and outputs only the red signal, the green signal, and the blue signal from the video signals input six times at the 1st, 2nd, and 3rd times, respectively. This red.

The green and blue signals are sequentially applied to the sixth node or first grid of the electron gun of the thin color cathode ray tube 20 having the fluorescent surface structure shown in FIG. The horizontal deflection frequency of this thin solar cathode ray tube 20 is six times that of the received video signal, and the red, green, and blue signals, each time-compressed to 1/3, are the received signal 6''). The signal processing circuit 19 outputs the color selection signal of the cathode ray tube 20, pressure application terminal 11. It is necessary to switch the voltage applied to 12.13.In the color cathode ray tube according to the present invention, the voltage applied to 6th
As shown in the figure, horizontal striped gold is used, so it is 6 times the normal horizontal frequency, or about 47kl in the NTSC system.
It is only necessary to switch at a cycle corresponding to 1z, and switching elements that can do this are easily available. Technologies such as line memory using COD, 3x wideband video frequency, 6x horizontal deflection frequency, etc. Both have already entered the practical stage. It should be noted that compared to the case of the set stripes shown in FIG. 2, when horizontal stripes are used as in the present invention, the number of times of high voltage switching is extremely small, so that the switching loss is also extremely small.

In the above explanation, all of the same color phosphor strips of a thin color cathode ray tube are electrically coupled to each other. of the same color phosphor strips, for example, first and second same color phosphor strips that are close to each other, and a fifth phosphor strip of the same color. Same color phosphor Stra Eve of WJ6
・And so on, the (4n-3)th and (4n-2)th same-color phosphor stripe groups, and the (+n-1)th and 4nth same-color phosphor stripe groups. If you separate the applied voltage into two groups, provide an applied voltage switching terminal for each group, and control the applied voltage for each terminal, the beam will be turned off) <'! = It is possible to prevent deterioration of vertical resolution even if the value is too large. If the spot diameter is even larger, it is better to further increase the number of divisions of the drive group of the same color.

FIG. 5 is a block diagram of a circuit for processing signals according to the second embodiment. A video signal is applied to the terminal 21, and six outputs of R, G, and B are obtained simultaneously by a normal color demodulation circuit 22. These outputs are respectively output from the first line memory 23.
24, 25 to store information for one horizontal period, and then transferred to second line memories 26, 27, and 28, respectively. The read speed from the second line memory is three times the write speed to the first line memory, and the read timing is, for example, 1/6 at the beginning of one horizontal period for the memory 26. The memory 27 is located in the center 1/6. The memories 28 are controlled so that they do not overlap in time, such as at end 1/ro. 2nd line memory 26.27
．． The outputs of 28 are temporally rearranged in series by an adder circuit 29 and supplied to a thin color cathode ray tube 20. Although the number of line memories is increased compared to the first embodiment, the configuration of the color demodulation circuit 22 is extremely simple because it can process at the normal frequency of 3.58 M Ilz.

The order of application of the three primary color signals is R, G.

It is possible to repeat B. In this case, for example, N'l”
In order to almost completely display a color image using the SC method, the number of horizontal stripes of the phosphor must be approximately 480 x 3.
=1.440 pieces are required. Therefore, there is no problem in the case of a large screen, but in the case of a small screen of about 6 inches, for example, the vertical dimension is about 45 mm, so if the phosphor stripe spacing and stripe width are the same, the stripe width is about 15 μm.
m (45g, ---1,440X2 156μm), and considering that the phosphor particle size is about 1oμm and the withstand voltage between each stripe, arranging such a large number of horizontal stripes is as follows. Virtually impossible.

If you abandon interlacing, the number of stripes will be about 24.
0 x 3 = 720 lines, and the stripe width is approximately 6
Since it is 0 μm, it becomes more practical, but deterioration in vertical resolution cannot be avoided. As a third embodiment to solve this problem, the order of the primary color signals is changed, and the n-th signal of the odd field is
In the Tfth horizontal scanning period, R, G, B in the order of n+
In the i-th order, B, R, G, in the n+2-th order, G, ]3
．． This is repeated in the order of H, and the nth even field (in the NTSC system, the n+26th odd field
In the 3rd test), G, BR in the order, and in the n+1st test, R, G
, in the order of H, at the (n+2)th, B, R, G JllIlt
If we decide to return this in Km, then if we switch the voltages applied to terminals 11, 12, and 13 in accordance with this signal order, we get
As shown in Figure 6, the number of stripes required is approximately 240.
X 2 = 480 lines, and the stripe width is 45 μm
Moreover, because it uses ink-lace scanning, the vertical resolution does not deteriorate. In this third embodiment, B, G, R, .
...It is necessary to repeat the excitation of R, G, and B by repeating the horizontal wall optical drive twice, and the vertical deflection must be devised, but this is not possible with the thin cathode ray tube shown in This can be achieved by only slightly changing the voltage waveform applied between the side surfaces 5 and 6. Further, if the beam diameter is 11/36P or more relative to the KGB triplet pitch P, correct color reproduction can be achieved as shown in FIG. 7 without any special measures.

〔Effect of the invention〕

As explained above, according to the present invention, a thin color image display device is capable of displaying an image with high color saturation with high electron beam utilization efficiency and low switching loss without deterioration of vertical resolution. is obtained.

[Brief explanation of the drawing]

Figure 1 (A) is a front view of a monochrome thin cathode ray tube, (
B) is a side sectional view, FIG. 2 is an enlarged structural view of the fluorescent surface of an example of a conventional thin color cathode ray tube proposal, and FIG. 6 is a partially enlarged view of the fluorescent surface of the thin color cathode ray tube according to the present invention. Structure diagram: FIG. 4 is a block diagram of a circuit for processing signals according to the first embodiment of the present invention;
FIG. 5 is a block diagram of a circuit for processing signals of the second embodiment. FIGS. 6 and 7 are explanatory diagrams of the operation of the sixth embodiment. ,2
3゜24.25...First line memory 17.26.
27.28... Second line memory 18... Feedback loop 19... Signal processing circuit 2o... Thin color cathode ray tube 22... Color demodulation circuit 29...
Adder RlG, B... Red, green, and blue phosphor stripes, respectively.Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (3)

[Claims] (1) On each horizontal strip electrode that is electrically insulated from each other and arranged approximately parallel to the scanning direction of the electron beam,
A group of colored phosphor stripes consisting of repeating silk coated with red, green, and blue phosphors is provided, and each of these phosphor stripes of the same color is electrically connected to each other, allowing for color selection outside the tube. A thin color cathode ray tube that is connected to a voltage application terminal; a first line memory that inputs video signals in series, stores them, and outputs them in parallel; 3 speeds of writing to memory
A time axis compression memory circuit consisting of a second line memory that serially outputs at twice the speed and circulates the memory contents in the form of serial output - serial input so that the same information can be obtained six times at its output terminal. a circuit that demodulates red, green, and blue color signals for the six outputs of the second line memory; and a horizontal deflection circuit that deflects the input video signal at a period of 1/vertical to the horizontal period of the input video signal. and; a thin color image display device characterized in that it is equipped with means for switching the voltage applied to the color selection voltage application terminal outside the cathode switching in synchronization with the demodulation of the color signals of the above-mentioned addition, green and blue. (2) Color demodulation is performed before time-base compression is performed using a memory circuit, and time-base compression is performed at the stage of the color difference signal or primary color signal after this demodulation, and the red, green, and blue color signals are temporally serialized. 2. A thin color image display device according to claim 1, wherein the thin color image display device is arranged in such a manner that the display device is rearranged into two shapes. (3) A colored phosphor consisting of a repeating set of red, green, and blue phosphors coated on each horizontal strip electrode that is electrically insulated from each other and arranged approximately parallel to the scanning direction of the electron beam. A thin color cathode ray tube is provided with a group of light stripes 5, each of which has the same color of these phosphor stripes is electrically connected to each other, and connected to a color selection voltage application terminal outside the tube: an input image. Red and green from traffic lights. a circuit for fully demodulating the back color signal; a memory circuit for time axis compression; a horizontal deflection circuit that deflects at a period of 1/3 with respect to the horizontal period of the input video signal; synchronized with the input of the color signal, and
means for switching the voltage applied to the color selection voltage application terminal outside the cathode ray tube according to each color; the color signal Tn R'A1 circuit and the memory circuit cooperate to , each primary color signal has an output speed that is three times the input speed, and each primary color signal has a CI, C2+, respectively.
When C3, in the n@th horizontal scanning period of the odd field, the 11th shift of CI + C2C5, the nth +11f
In the order of C3, C1, C2, 1l-1 at the n+2th
: C2, C3, Cs in order, 1, nth even field
In the th order, C2, C3, C1, in the n+i th case, C1,
The means for switching the color selection voltage is operated by repeatedly outputting the input video signal in the order of C2 and C3, and in the order of C3, C1, and C2 in the (n+2)th project, with 6 horizontal scanning periods of the input video signal being one cycle. A thin color image display device characterized by: