JPS6034781B2 - cathode ray tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel television cathode ray tube, more specifically, a novel television cathode ray tube having one electron gun and a halo film for displaying chromatic colors using black and white television signals. It is related to.

Conventionally, there are two main types of television reception systems: black-and-white and color; black-and-white television cathode-ray tubes are used for black-and-white, and color television cathode-ray tubes are used for color.

The former has one electron gun and a crab light film that displays images by changing the brightness of an achromatic color, while the latter has three or one electron gun.
The electron gun and dot-like or stripe-like crab light bodies that emit light in the three primary colors of red, green, and blue, and whose brightness changes depending on the intensity (current density) of the electron beam, provide a natural-color light-emitting display as a whole. It has a crab film that makes
The electron gun is controlled by a black-and-white television signal and a color television signal, respectively, to display a black-and-white image and a color image. Since black-and-white televisions that display images by changing the brightness of achromatic colors produce very monotonous and uninteresting images, color televisions that emit light in natural colors are now widely used.

However, color television requires complex methods for photographing, transmitting, and receiving, and is expensive, so there are many regions where black-and-white televisions are used exclusively due to equipment constraints and economic conditions.

Further, due to similar constraints and conditions, there are many fields where black and white televisions are used exclusively depending on the purpose. Therefore, the equipment cost is relatively low like black and white television,
Moreover, although there is a desire for a television system that solves the monotony of images in black-and-white television, there is currently no system that meets such demands.

Although it is possible to display chromatic television images at low cost by using the conventional black-and-white television system as is, this does not solve the monotony of the images. That is,
If you change the mixing ratio of the blue light-emitting crab light and the yellow light-emitting light that make up the crab light film of a cathode ray tube to create a blue (blue-white) or yellow (yellow-white) light-emitting crab light film, a monochromatic color can be produced. A so-called monochrome image display can be achieved by changing the brightness of the image. However, the crab light body used in the conventional crab light film is Z
A blue light-emitting light body whose brightness increases linearly with an increase in current density, such as an nS:Ag light body, that is, a blue light-emitting light body having a linear current density-luminance characteristic; ,Cd)S:Ag crab photon, (Zn,Cd)S:
It is made of a combination with a yellow light-emitting crab light body such as a C and N crab light body which also has a linear current density-brightness characteristic, and the current density-brightness characteristic is linear. The light emission brightness of the crab light film is controlled by controlling the beam current in response to the black and white television signals from the dark level signal (0 signal) to the highlight signal, and an image is displayed by the change in brightness. Therefore, since the colors do not change in response to changes in the beam current, not only is the monotony of the image not improved at all, but also the range of brightness changes in chromatic colors is narrower than in achromatic colors. This results in a display with lower contrast than image display based on brightness changes. Since the human eye is more sensitive to changes in color than to changes in brightness of achromatic colors, ie, changes in black and white, the monotony of this image can be improved by converting black and white changes into changes in color.

The applicant has conducted research based on this idea, and found that even if the conventional black and white television system signal is used as is,
If the highlight signal is displayed in white, and the signal between the highlight signal and the dark level signal is displayed in a chromatic color whose color changes continuously depending on the brightness, the monotony of the image seen in black and white television systems can be improved. It has been discovered that it is possible to obtain images with completely new tones that have never been seen before, and which can fully satisfy the color emotions of the viewer.

The present invention provides a halo film useful in this new concept, that is, a halo film that displays highlight signals in white when irradiated with an electron beam corresponding to a conventional black and white television signal,
It is an object of the present invention to provide a cathode ray tube having a crab light film that displays a signal intermediate between a highlight signal and a dark level signal in chromatic colors that change continuously depending on the brightness.

As described above, the cathode ray tube of the present invention uses black and white television signals as they are, so conventional black and white television equipment can be used as they are. Since it is shown in white, it is possible to obtain images with new and interesting color tones at low cost, and it provides a useful method in addition to the conventional two methods, black and white and color. The industrial value is significant. Furthermore, as is well known, in color television (NTSC system), a luminance signal (Y signal) and a color signal (1
, Q signal) is used to record and reproduce images, and this luminance signal (Y signal) is equivalent to the luminance signal of conventional black and white televisions (for example, Ohm's "Electronics Pocket"). In the present invention, this luminance signal can also be used as the above-mentioned black-and-white television signal.

Therefore, in the system using the cathode ray tube of the present invention, conventional color television equipment can be used as is. Note that in this specification, the luminance signal in color television is also referred to as a "monochrome television signal." Hereinafter, the structure and operation of the cathode ray tube of the present invention will be explained in detail.

The structure of the cathode ray tube of the present invention is exactly the same as that of a conventional black and white television cathode ray tube, except for the rear light film, as shown in FIG.

That is, the cathode ray tube of the present invention has one electron gun 3 in the neck part 2 of the funnel, and a crab light film 5 is formed on the entire surface of the face plate 4 facing the electron gun 3.
In the cathode ray tube configured as described above, the light film is composed of a single light body having two or more emission bands, and at least one of the light emission bands has a nonlinear current density. The light emission color of the crab light film changes continuously, including white in the CIE color system, in response to the beam current. Note that reference numeral 6 indicates an electron beam emitted from the electron gun 2 and irradiated onto the crab light film 5. Non-linear current density-brightness characteristic means that the linearity of brightness is lost as the current density increases;
Crab photons having brightness characteristics are classified into sublinear type and superlinear type.

Sublinear crab photons are those in which the brightness deviates from a straight line as the current density increases (the gradient of the increase in brightness becomes smaller), whereas superlinear crab photons are the ones in which the brightness deviates from a straight line as the current density increases (the gradient of the increase in brightness becomes smaller); (the gradient of becomes larger).
The emitted light color of a crab photon having two or more emission bands is determined by the emission color and luminance amount (brightness) of the crab photon in each emission band. The light-emitting film of the cathode ray tube of the present invention is composed of a single light-emitting band that includes at least one light-emitting band with a change in beam current. Because it changes continuously in response to
The color of the emitted light changes continuously in response to changes in the system current.

As described above, the crab light film of the cathode ray tube of the present invention is composed of a single bag light body having two or more light emission bands in which at least one light emission band has non-linear current density-luminance characteristics. The color changes continuously in response to changes in the beam current, but another important characteristic that this crab-light film must have is the ability to emit light that changes continuously in response to changes in the beam current. It is the inclusion of white among colors.

As mentioned earlier, in a new image display method that uses a black-and-white television signal and changes color along with brightness, the highlight signal is displayed in white. A crab light film that does not include white in the emitted light color that changes continuously in response to changes in beam current cannot be used as the bottom light film of the cathode ray tube of the present invention. The white color mentioned above is the second color.
This refers to the area indicated by diagonal lines in the CIE color system chromaticity coordinates in the figure, that is, white in the CIE color system. Basically, at least one of the crab phosphors used in the crab phosphor film of the cathode ray tube of the present invention has an unreasonable current density-luminance characteristic, and a straight line connecting the emission chromaticity points of each CIE display system is , second
It is a single halo having two emission bands that pass through the white region indicated by diagonal lines in the figure.

3A to 3C schematically show the current density-brightness characteristics of each emission band in the crab light film of the cathode ray tube of the present invention using a single crab light body having such two emission bands, Figure 3A shows that the two types of fluorophores are sublinear type emission band A and IJ near type emission band B, and Figure 3B shows that the two types of emission bands are linear type emission band A and superlinear type emission band B. In this case, FIG. 3C shows a case where the two emission bands are a sublinear emission band A and a superlinear emission band B. In the crab light film of the cathode ray tube of the present invention shown in FIGS. 3A to 3C, the luminance of emission band A is superior to that of emission band B in the region below the current density lo, so that in this region, the crab light film is The luminescent color is always a warm color in which the luminescent color of luminescent band A is predominant.
On the other hand, in a region where the current density is lo or more, the amount of light emitted from light emitting band B exceeds that from light emitting band A, so in this region, the light emitted by the crab's light film is always the color of light emitted from light emitting band B. becomes a dominant color mixture. Therefore, the emitted light color of the crab light film changes continuously in response to an increase in current density from a mixed color in which the emitted light color of the emissive band A is predominant to a mixed color in which the emitted light color of the emissive band B is predominant. CI shows how the luminescent color changes.
In terms of the E color system, the luminescent color changes from near the luminescent chromaticity point of luminescent band A to the luminescent chromaticity point of luminescent band B on a straight line connecting the luminescent chromaticity points of both luminescent bands in response to an increase in current density. It will move continuously in the direction. In the current density range of 1 to 12, the crab light film emits white light.
In other words, in the region where the current density is 1 to 12, the C of the crab light film is
Make sure that the emission chromaticity point of the IE color system is within the white area indicated by the diagonal lines in Figure 2, and that the highlight signal is 1 to 1.
If the black-and-white television signal is converted to an electron beam so that it can take an appropriate current density value within the range of 2, the highlight signal becomes white, and each signal from the highlight signal to the dark level signal becomes emission band A. Displayed in a chromatic color that continuously changes from white toward the emission chromaticity point of emission band A on a straight line connecting the emission chromaticity points of emission band B,
A new image display method, which is the object of the present invention, is realized.
It is preferable that the light emitter is a crab light body that emits white light at high current density, like the halo body shown in FIGS. 3A to 3C. This means that in the case of a phosphor that emits white light at low to medium current densities, not only will the chromatic color change range in each signal between the highlight signal and the dark level signal become narrow, but the brightness will be insufficient. This is because the display screen becomes dark. Furthermore, as shown in Fig. 3C, the current density-luminance characteristics of luminescent bands A and B are such that if one is a superlinear luminescent band and the other is a sublinear luminescent band, the luminance of both luminescent bands in a certain current density range Since the ratio width can be wider, a halo film with a wider range of color changes can be obtained by using this crab phosphor. The case where a crab light body having two emission bands is used has been described above, but the crab light film of the cathode ray tube used in the present invention is not limited to this, and has three or more emission bands, among which at least one of them has a non-linear current density-luminance characteristic, and the luminescent color of the crab light film changes continuously, including white in the CIE color system, in response to changes in the beam current. Needless to say, it may be a crab photoreceptor.

The crab light material used in the crab light film of the cathode ray tube of the present invention is C.
Examples include aGa407:Mn crab photon, BeGa204:Mn crab photon, Shigeru2Si04:Mn crab photon, and the like.

All of the three types of crab photons are sublinear type activators M.
It has two emission bands consisting of an n emission band and a superlinear parent emission band, and when these three types of crab photons are excited with an electron gun, the emission color depends on the current density. The color changes continuously from yellow to white as the color increases. That is, at low current density, yellow luminescence around 57 arms due to the activator Mn appears prominently,
The amount of yellow light emitted increases sublinearly as the current density increases, and reaches saturation above a certain current density value. On the other hand, the amount of blue light emitted by the matrix is very small at low voltages, but increases superlinearly as the current density increases. Therefore, activator skin n
The ratio of the amount of yellow light emitted by the body to the amount of blue light emitted by the host body changes continuously in response to an increase in current density, and the color of the light emitted by the crab body changes from yellow to yellow and blue in response to an increase in current density. It changes continuously to a mixed white color. Figures 4A and 48 show CaGa407 at current density values of 0.1 μA/c and 101 A/c, respectively:
Mn crab photon (Mn activation amount is 3 x 10-5 g atoms/mol
) are both the emission spectra of 573 due to the activator Mn.
It is normalized and shown using the luminescence band peak of the skin.
In Fig. 4A, the emitted light color at a current density value of 0.1 French A/ is almost yellow, and its CIE color system emission chromaticity point is the chromaticity point Y (x = 0.472, Y =0.460
). On the other hand, Fig. 48, that is, current density value 10 peaks A
The emission color at / is white, and the emission chromaticity point in the CIE color system is the chromaticity point W (X=0.370, Y=0
．． 372). Therefore, this Mn activation amount is 3×10-
In a cathode ray tube with a CaGa407:Mn light film of 5 g atoms/mol, the black-and-white television signal-electron beam conversion is set so that the current density value of the highlight signal is 10 μA/mol. By doing this, the highlight signal becomes white at chromaticity point W, and each signal from the highlight signal to the dark level signal becomes chromaticity point W and chromaticity point Y.
It can be displayed in chromatic colors that move continuously from W to Y direction on a straight line connecting . By using the cathode ray tube of the present invention in combination with a black and white television signal, the cathode ray tube of the present invention can fully satisfy the viewer's color sense without the monotony of images seen in conventional black and white television systems. It is possible to easily display images with new tones, and its industrial utility value is tremendous as described above.

[Brief Description of the Drawings] - Figure 1 is a schematic diagram of a black and white television cathode ray tube. FIG. 2 shows white in the CIE color system in chromaticity coordinates. FIG. 3 schematically shows the current density-brightness characteristics of each emission band in the crab light film of the cathode ray tube of the present invention using a crab light body having two emission bands.
When the two emission bands are sublinear emission band A and linear emission band B, Fig. 3b is the same as when the two emission bands are linear emission band A and superlinear emission band B, and Fig. 3c is 2. 3 shows the case where the two emission bands are a sublinear emission band A and a superlinear emission band B, respectively. Figures 4A and 4
Figure B shows the emission spectra of the Ca○a407:Mn crab photoform with an Mn activation amount of 3 x 10 atoms/mol at current densities of 0.1 and 10 A/mol, respectively.
All are normalized to the emission band peak of 573 ribs due to the host agent Mn. Figure 5 shows CaGa407:M with Mn activation amount of 3 x 10-5 g atoms/mol.
The emission chromaticity point Y at a current density value of 0.1 rA/2 and the emission chromaticity point W at a turtle current density value of 10 μA/2 are shown in the CIE color system chromaticity coordinates. 1...
...Fannel, 2...Neck part, 3...
・Electron gun, 4...Face plate, 5...
・Crab light film, 6. ...Electron beam. FIG. lFI■G. 2 FIG. 3A FIG. 3B FIG. 3C FIG. 4A FIG. 4B FIG. 5

Claims (1)

[Claims] 1. In a cathode ray tube consisting of one electron gun and a funnel having a fluorescent film on the entire surface of the face plate facing the electron gun, the fluorescent film is made of a single phosphor having two or more emission bands. consists of a single phosphor having at least one of the emission bands, at least one of the emission bands has non-linear current density-brightness characteristics, and the emission color of the phosphor film depends on the beam current. When the fluorescent film is irradiated with an electron beam corresponding to a black-and-white television signal, the highlight signal changes to white, and the highlight signal changes continuously, including white in the CIE color system. A cathode ray tube characterized by displaying each signal between a signal and a dark level signal in chromatic colors.