JPS587749A - Color crt - Google Patents

Abstract

PURPOSE:To minimize the decrease of the laminescence output of a phosphor layer and to improve the outisde light contrast by forming a filter layer made of a neodymium compound between a glass panel and the phosphor layer. CONSTITUTION:A filter particle layer 2, which is made of a neodymium compound such as neodymium oxide, neodymium silicate, or neodymium aluminate, and strongly reflects the blue light near 440nm green light near 550nm, and red light at 610nm or above and strongly absorbs the light at wave length regions between them is formed between a phosphor layer 3 and a front glass panel 1, or the filter particles are contained in the phosphor layer 3. Accordingly, one kind of filter particle is used in common for the blue, green, and red phosphors, thereby the work process can be simplified, the phosphor layer 3 can be prevented form being deteriorated in performance, and the outside light contract can be improved.

Description

[Detailed description of the invention] This book is about color cathode ray tubes.

In color televisions, many methods have been proposed to improve the contrast of the image 110 in bright outside light.

In general, there are two methods: using glass with low light transmittance as the front glass panel, blackening the part of the front glass panel where the phosphor layer is not coated, and attaching filter particles to the phosphor particles. A method in which a filter particle layer is interposed between the phosphor particle layer and the front glass panel has been used. Among these methods, in the method of using a glass panel with low light transmittance, the transmittance of the light emitted by the phosphor also decreases at the same time, resulting in a dark screen. The method of blackening the area where the phosphor layer is not coated has the disadvantage that the reflection of external light cannot be sufficiently reduced because the area of the black area occupies a small proportion of the total area. Also, the above-mentioned method of combining a phosphor and filter particles has various drawbacks.

For example, when attaching filter particles to phosphor particles, the filter particles tend to peel off from the phosphor particles when the phosphor is applied to the inner surface of the front glass panel to form a phosphor layer. The contamination of the filter particles with other phosphor layers significantly reduces the emission of the other phosphor layers.

In addition, in the conventional method of interposing a filter particle layer between the phosphor particle layer and the glass panel surface, a separate filter particle layer is required for each of the blue phosphor layer, green phosphor layer, and red phosphor layer. In order to form a phosphor layer, the number of manufacturing factories has increased dramatically, the incidence of defects has increased, and since different filter materials are used for each phosphor layer, due to mutual contamination, 11imoqi4
I can't get enough lightness.

The present invention has been made to solve this conventional 1%1 problem.

That is, as shown in $11111, the filter layer (2) interposed between the phosphor layer (3) and the front glass panel (1)
) as a phosphor layer (
8) The number of filter particles of the same type within the group is smaller than the number of filter particles (both are characterized by one).

The filter particles used in this study are neodymium oxide,
Neodymium compounds such as neodymium silicate and neodymium aluminate strongly reflect the green emission near 44Qnm, the green emission near ssO, and the red emission of 6101151 or higher, and in the wavelength range between 5 and 5, mainly 120aaI and 51
It has a strong ms at a wavelength around 10 am.

These filter particles are not altered by heat treatment during the manufacture of color cathode ray tubes and exhibit stable reflection 4+1 properties.

Curve showing the reflectance of Iris 2WA&i neodymium oxide (4)
The liquid lengths of the reflection peaks are defined as blue emission (5), green emission (6), and red emission (7) of a color cathode ray tube, as shown in JI3al.

Honjitsu 911+2) color cathode ray tubes can be manufactured according to a normal fluorescent surface development process. That is, prior to forming a phosphor layer on the front glass panel surface, neodymium oxide particles are coated and adhered to the glass panel, and the external light reflectance of both screens can be adjusted by adjusting the amount of adhesion. Sufficient adhesion of neodymium oxide to the glass surface can be obtained by performing normal exposure and development on the 4i surface of the glass panel coating surface.

Next, blue, green, and red phosphor layers are regularly deposited on the neodymium oxide coated glass panel surface by a conventional method.

The light from the incandescent bulbs roars on the color cathode ray tube wall and light tone.
The external light reflectance is calculated by dividing the amount of light reflected from the fluorescent surface by the amount of light reflected from the standard white plate. Actually, a connection.

The red-emitting phosphors were a silver-coated zinc sulfide phosphor, a copper-coated sulfurized lead phosphor, and a europium-coated yttrium oxysulfide phosphor. Between mK blue, rim.

Since the red-emitting phosphor is used, the external light reflectance of a conventional color cathode ray tube is 4111, while that of the Tacolor cathode ray tube formed with a neodymium oxide layer of three tone thickness of the present invention is 35.6. , an improvement of about 15- was observed.

In this project, one type of filter particle is commonly used for blue, green, and red phosphors, so compared to the conventional case of using different filter particles for each phosphor, the filter particles are different from each other. **Deterioration due to contamination is eliminated (41), and at the same time, the defect rate in the factory is reduced.

In this invention, we use a phosphor with a filter in which neodymium compound filter particles are layered on both lengths of the phosphor particles, or a mixture of neodymium compound filter particles and the phosphor, and use ordinary phosphor. The optical IMM process yields a color cathode ray tube containing filter particles within the phosphor layer.

In this case as well, the brightness and contrast characteristics are greatly improved compared to conventional color cathode ray tubes containing filter particles.

Moreover, by interposing neodymium compound filter particles between the front glass panel surface and the phosphor layer, and further including the neodymium compound filter particles in the phosphor layer, a sufficiently higher contrast characteristic can be obtained.

The color cathode ray tube of the present invention uses the same material for blue, green, and red as filter particles, and can minimize the decrease in light output of the phosphor layer and improve the external light contrast, which is different from conventional color cathode ray tubes. It exhibits much superior characteristics compared to other materials.

[Brief explanation of drawings]

Figure 1 is a partial cross-sectional view showing the main parts of the color cathode ray tube according to the present invention, the 1m2 diagram is a diagram showing the reflection spectrum distribution of neodymium oxide, and Figure 3 is the emission spectrum of typical blue, green, and red phosphors. It is a figure showing distribution. (1) Glass pile (2) Filter single layer (+3) Fluorescent layer (4) Reflectance characteristics of neodymium oxide (7317) m Patent attorney Noriyuki Norichika (and 1 other person) No.
1 Figure # 匈 61)l
711 waves & C71m)

Claims (1)

[Claims] In a color cathode ray tube in which phosphor layers that emit red, green, and blue light are regularly deposited on the inner surface of a glass panel by the impingement of an electron beam, ? 1. A filter layer made of neodymium A metal is formed between the glass panel and the phosphor layer.