CN1008228B - Fluorescent indicator with high brightness - Google Patents

Abstract

The present invention provides a high-luminance image element pipe with a large image element, which is manufactured by utilizing a fluorescent display principle and an anode with a thin wall and a curved face. The anode with a thin wall, a curved face and high heat conductivity enlarges a heat radiation area and a luminous area; direct vision lighting is adopted; therefore, the image element pipe has the advantages of high efficiency, high brightness, low driving voltage and simple structure with N*M image elements integrated in the same base plate. The image element pipe can be used for constructing large-sized and super-sized monochromatic, multi-colored and chromatic display screens, and can display characters, Chinese characters, tracks, television images, etc.

Description

Fluorescent indicator with high brightness

The present invention relates to have the High-Bright Vacuum Fluorescent Display Device of curved surface anode, and the display that becomes matrix form to arrange.

At present the display of outdoor large and ultra-large type matrix display system mainly contains three kinds: 1. incandescent lamp; 2. general beam cathode ray tube (Flood Beam CRT), 3. high-pressure fluorescence picture dot pipe.

The incandescent lamp price is low, bought easily, often is used to outdoor large before the earlier year and shows.But its power consumption is big, reaction speed slow, drive circuit cost height; Be mainly used in some simple characters at present and show, seldom be used for image and show and large-scale, ultra-large type matrix display system.

General beam cathode ray tube is day the present invention's several years ago a kind of large-scale, a ultra-large type matrix demonstration picture dot pipe.It is that a kind of diameter is 1 inch, is about 15Cm, electron gun is arranged and the cathode ray tube of zero deflection system, a pixel of a pipe.Several ten thousand or hundreds of thousands only this three primary colors general beam tube by certain mode arrange constitute large-scale or the ultra-large type colorful display screen with displayed image or character etc.In fact each only general beam tube is exactly a little picture tube, thereby cost is very high, and it also needs 8000 to 10000 volts high voltage.

High-pressure fluorescence picture dot pipe be 1984 by the invention of Japanese Sony and Putaba company, each display tube comprises each one of red bluish-green three primary colors picture dot.Build that to have put on display its screen of making of a cover in the fair of ripple international scientific technology first be the ultra-large type color TV display system of 25 * 40m in March, 1985 in Japan, this picture dot pipe can be used for stimulated luminescence with 90% of input power, but it adopts transmission mode, the exitance of light is low, thereby actual luminous efficiency is not high.Next its same high pressure that needs the 5000-10000 volt with general beam cathode ray tube, drive circuit complexity, cost height, maintenance is inconvenient when outdoor rainy day, mould season.

The present invention utilizes the low-voltage fluorescence displaying principle to make a kind of high brightness color fluorescence matrix display that can be used for the large-scale of monochrome, polychrome or colour, indoor or outdoors or ultra-large type display system.Only about 100 volts of its high driving voltage, than low 50 to 100 times of high-pressure fluorescence picture dot pipe, thereby available integrated circuit directly drives, and cost is low; The exitance of light is up to 90%, and is higher 1 times than high-pressure fluorescence picture dot pipe.Thereby can constitute efficient height, cost large-scale and ultra-large type matrix display system low, safe, easy to maintenance.

According to the present invention, a kind of High-Bright Vacuum Fluorescent Display Device comprises transparency carrier as light-emitting face, constitutes the shell of airtight vacuum system with glass substrate, it is characterized in that, constitute shell by n * m thin-wall curved-surface pixel pipe shell, negative electrode and grid that emitting electrons is arranged in each pixel shell, inner wall of tube shell has the low resistance conductive layer as anode, is luminescent powder on the conductive layer, and the shell outer wall has high reflector layer.

Fig. 1 is the schematic diagram of high voltage fluorescence picture dot pipe of the prior art.

Fig. 2 is another view of picture dot pipe shown in Figure 1;

Fig. 3 is the schematic diagram of High-Bright Vacuum Fluorescent Display Device of the present invention;

Fig. 4 is the end view of display shown in Figure 3;

Fig. 5 is the cutaway view of each pixel pipe in the display of the present invention;

Fig. 6 is the grid schematic diagram of pixel pipe shown in Figure 5;

Fig. 7 is the shell figure of pixel pipe shown in Figure 5.

Fig. 1 is the high-pressure fluorescence picture dot pipe of Japanese Sony in 1984 and Futaba invention, and wherein 1 be the directly-heated type oxide coated cathode, and 2 is grid, and 3 is the anode that is added with 5000 to 10000 volts of high pressure, has red blue or green three primary colors luminous 4 above it.Each display tube has red, blue, green three picture dots.5 is the aluminium dividing plate, is used to cut off the light of directive adjacent pixel and makes it reflection to improve brightness and contrast, and 6 is glass shell.

The bright dipping mode of this kind high-pressure fluorescence picture dot pipe is a transmission-type.Electron excitation produced luminous half (7 among the figure), half (8 among Fig. 2) backward forward; To forward part is actual useful light, it partly passes through the absorption of luminescent layer and the absorption of scattering and glass and conductive layer, counting to the light of rear section through reflection repeatedly again behind forward the light, the luminous flux of actual outgoing still approximately has only about 40% of total light yield, be that the outgoing coefficient of light is about 0.4, thereby efficient is not high.

Secondly, the anode voltage of high-pressure fluorescence picture dot pipe is up to 5000 to 10000 volts, and anode driving circuit cost height keeps in repair inconvenience, particularly in rainy day, mould season or high humility area.

The present invention has overcome above-mentioned shortcoming, only about 100 volts of maximum operating voltage, and available integrated circuit directly drives; The daylighting mode adopts direct-viewing type, and glass bulb has high reflected coat layer, makes luminous exitance bring up to about 90%.

The structure of large image element High-Bright Vacuum Fluorescent Display Device of the present invention (abbreviation high brightness indicator) as shown in Figure 3, wherein 9 is transparent glass substrate, n * m (being 2 * 2 among the figure) individual luminous tube 10 arranged on it, 11 is blast pipe, in the blast pipe is getter 12, and n * m luminous tube is all with being interconnected to a vacuum system communicating pipe 13, and 14 is cathode terminal, 15 is grid lead wire, and 16 is anode lead wire.Fig. 4 is the profile of luminous tube 10.Wherein 17 is the conical directly-heated type filament negative electrode of arranging, and 18 be conical butt grid (see figure 5), and 19 for the top is that hemispheric taper shape approaches glass shell, and this glass bulb also can adopt other forms, as parabola etc.; Its inwall is a low-resistance film conductive layer 20, is low-voltage luminescence powder 21 on the conductive layer, and its outer wall is highly-reflective coating and coarse black heat dissipating layer 22, if conductive layer 20 itself be exactly high reflection layer then outer wall only need consider the heat radiation.In order to intensify, the not luminous component of the outer surface of glass substrate 9 should be coated with black matrix layer 23, should add the colour filter 24 of the spectral transmittance that is complementary with illuminant colour to improve colorimetric purity and contrast over against the light transmission part of luminous tube.Use low-melting glass 25 sealing-ins between luminous tube, blast pipe and the glass substrate.

N * m luminous tube on glass substrate, for monochrome show, all luminous tubes all use with a kind of luminescent powder.For colour show then a kind of with three primary colors luminous, every pipe, press the arrangement of RGB certain rule.

Luminous tube can be used audion, also can form diode structure without grid.The latter can be with the anode zoning of each luminous tube, coat not homochromy luminescent powder respectively, as three primary colors luminous, voltage, each luminous tube of controlling each anode get final product shades of colour.

Glass substrate can be in advance made elements such as lead-in wire or capacitance-resistance of thick film technology, then integrated circuit socket etc. is welded on the substrate, constitutes the display module that has drive circuit, promptly can be spliced into large-scale or the ultra-large type display screen with this display module.

Because the saturated brightness that low-voltage fluorescence shows is subjected to the restriction of temperature quenching, the only about 5000cd/m of the saturated brightness of large area light emitting ²About, therefore be difficult to make low pressure large image element high brightness display tube with structure shown in Figure 1.It is hemispheric cone glass bulb (or wait other curved surface with parabola) that the present invention adopts the top, increase light-emitting area and area of dissipation, to improve brightness, Fig. 7 is the conical luminous tube on hemisphere top, cooperates suitable conical negative electrode and grid can make whole pipe luminous evenly.If the brightness Bo of light-emitting area at this moment, then the brightness of light-emitting face is:

$\mathrm{B\; =}\frac{\mathrm{K\; B\; o}}{R^2}\mathrm{(\; R}\sqrt{R{}^2\mathrm{+\; H}{}^2}\mathrm{-\; \gamma }\sqrt{\mathrm{\gamma \; +\; (\; H\; -\; h\; )}{}^2}{\mathrm{+\; 2\; r}}^2)$

Wherein R is a luminous tube awl bottom surface inside radius, and H is the cone height, and h is a frustum of a cone height, and r is a semi-round ball top radius, and K is the outgoing coefficient of light; Consider that luminous tube has highly-reflective coating, thereby luminous outgoing coefficient depends mainly on the transparency of the reflectivity and the glass substrate of luminescent layer, for transparent glass substrate, the K value can reach about 0.9.For example, Bo=5000cd/m ², R=13.5mm, H=90mm, h=66mm, r=4.5mm, K=0.9, then luminous tube brightness reaches 28,621cd/m ²

In addition, we are verified:

$\mathrm{B\; o\; \approx }\frac{C_2{\mathrm{(\; a\; -\; To\; )}}^2\lambda }{{\mathrm{4\; b\; Q\; (\; 1-\; \eta }}_o\mathrm{)\; d}}$

C wherein ₂With Q be constant, a and b are the constant that is decided by the luminescent material characteristic, for ZnO: Zn, a ≈ 140, b ≈ 130, η _OBe luminous energy efficiency, To is the temperature of glass bulb outer wall, and λ is the thermal conductivity of envelope material, and d is its thickness.Conical glass bulb of the present invention allows to adopt the thickness littler than Sony structure, also can adopt metal, thereby improves brightness and efficient.

Compared with prior art, the present invention has following advantage:

1. the anode voltage of general beam cathode ray tube and Sony, Futaba high-pressure fluorescence picture dot pipe is up to 5000 to 10000 volts, about 100 volts of the present invention's high brightness indicator ceiling voltage; The former voltage height, anode circuit cost height, mould season maintenance of rainy day are inconvenient; Operating voltage of the present invention is low, and available integrated circuit directly drives, and is easy to maintenance, and cost is low.

2. the bright dipping transmission mode of Sony high-pressure fluorescence picture dot pipe, luminous actual effectively exitance only about 40%.The present invention adopts the direct-injection type highly-reflective coating, and luminous actual effectively exitance reaches about 90%.

3. the light-emitting area of Sony high-pressure fluorescence picture dot pipe is little, and thickness of glass is big, the heat radiation difficulty, and luminous efficiency is low, needs to cool off with high wind.The present invention's luminous tube adopts the conical structure on ball top, and with thin-walled glass or metal, good heat dissipation, and light-emitting area is big, brightness height, efficient height.

4. pixel of each pipe of general beam cathode ray tube, each structure by all means is all similar to picture tube, and cost is very high.Display of the present invention has n * m picture dot on a glass substrate, simple in structure, cost is low.

The display of 5. general beam cathode ray tube and Sony, Futaba high-pressure fluorescence picture dot pipe separates with drive circuit, and display of the present invention and drive circuit constitute one, more reasonable structure.

The present invention can first step manufacturing shows the large display screen of numeral, letter, Chinese character and symbol etc., is used for stadiums and keeps the score, shows ranking name etc. and station, harbour, highway, hotel store advert, military commanding, data processing terminal etc.Second step was made the ultra-large type color TV, was used for the Asian Games, stadiums, large board, computer public service terminals, military commanding, production control etc.

Claims (12)

1, a kind of High-Bright Vacuum Fluorescent Display Device comprises transparency carrier as light-emitting face, constitutes the shell of airtight vacuum system with glass substrate, it is characterized in that, constitute shell by n * m thin-wall curved-surface pixel shell, negative electrode and grid that emitting electrons is arranged in each shell, inner wall of tube shell has the low resistance conductive layer as anode, be luminescent powder on the conductive layer, the shell outer wall has high reflector layer.

According to the display of claim 1, it is characterized in that 2, above-mentioned shell is made by thin-walled high heat conductance glass.

According to the display of claim 1 or 2, it is characterized in that 3, the curved surface of above-mentioned shell is the cone that has the hemisphere face top.

According to the display of claim 1, it is characterized in that 4, its grid is made of wire.

According to the display of claim 1, it is characterized in that 5, above-mentioned shell is made of metal, and as anode and high reflector layer.

According to the display of claim 1, it is characterized in that 6, above-mentioned low resistance conductive layer is made by having high reflective characteristic conductance material, this conductive layer is also as above-mentioned high reflector layer.

7, according to the display of claim 1, it is characterized in that the colour filter that matches with illuminant colour being arranged, black matrix layer is arranged between each pixel pipe to intensify in the front of above-mentioned transparency carrier.

8,, it is characterized in that n is 1 according to the display of claim 1.

9, according to the display of claim 1, it is characterized in that the same luminescent powder of each pixel pipe, constitute monochromatic high brightness indicator.

According to the display of claim 1, it is characterized in that 10, above-mentioned pixel pipe uses three primary colors luminous respectively, and press the colorful light-emitting rule and arrange, constitute color monitor.

11,, it is characterized in that each pixel pipe can be three primary colors luminous by the lining of three-color light-emitting rule according to the display of claim 1.

According to the display of claim 1, it is characterized in that 12, above-mentioned luminescent powder is the low-voltage luminescent powder, such as ZnO: Zn.