JPS63284521A - Plane light emitting device - Google Patents

Abstract

PURPOSE:To control the intensity of light emission from a phosphor layer by providing a light shutter layer close to the photo excited phosphor layer and driving the shutter layer with an information signal. CONSTITUTION:A plane light emission layer 1 has the light shutter layers corresponding to all the R, B and G layers on the phosphor layer in the ratio of one to one. The individual shutter layers are sequentially switched with a horizontal vertical synchronizing signal S and transmit the quantity of light according to the size of a video signal. Therefore, fluorescence from the tri-color dots of the phosphor layer is selected by the shutter so as to emit light in plane shape from the upper surface of the layer 1. A light radiation part 2 generates ultraviolet light and makes it strike against the phosphor layer in order to generate the fluorescence from the R, B and G dots. The plane light emission layer has a liquid crystal layer in it and executes a shutter function by selecting the gradation state between transparency and opacity prepared according to the voltage impressing state to the liquid crystal layer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a planar light emitting device suitable for displaying characters and images.

[Conventional technology]

Examples of conventional thin light emitting devices (displays) include liquid crystal displays, plasma displays, electroluminescent displays, and light emitting diode displays.

[Problem that the invention seeks to solve]

Text and image displays have become increasingly important man-machine interfaces as we enter the information age, and their quality and variety are increasing. One of the characteristics required of displays for information processing device terminals is high definition and improved visibility.

The former corresponds to high-density information display, and the latter is important from an ergonomic perspective (easy identification, prevention of eye strain). For small displays of 20 inches or less used as terminal devices, there is a cathode ray tube display as a device that most reliably satisfies these required characteristics. Cathode ray tube displays have long been widely used in general households as video display devices (televisions), but improvements such as higher definition, flicker prevention, and higher contrast are needed for information processing terminals (still images). is being measured. However, since cathode ray tubes utilize the phosphor excitation phenomenon caused by high-speed electron beams, the high voltage (-10 KV) and depth (several tens of ann) required to accelerate the electron beams are bottlenecks in their ease of use. In addition, the weight of the device, including the step-up transformer, deflection yoke, etc., is more than a few pounds.

Compatibility with electronic devices, which are characterized by their lightness, thickness, shortness, and smallness, is gradually becoming worse. Therefore, various so-called flat displays have been developed as display devices to compensate for this drawback, and some of them, such as liquid crystal displays, plasma displays, fluorescent display tube displays, electroluminescent displays, and light emitting diode displays, have been put into practical use. Among these, all devices other than liquid crystal displays are self-luminous devices, but their luminous efficiency (electricity → light energy conversion efficiency) is about 0.01 to 0.1%, which is about 2% to that of cathode ray tube displays.
There is a major problem in that it is more than an order of magnitude lower than 3%. On the other hand, since liquid crystal displays are non-luminescent, they have the advantage of low driving voltage, extremely low power consumption, and less eye strain, but their visibility is such that they cannot be used in dark places, are viewing angle dependent, and have low contrast ratios. have problems with. Therefore, in recent years, backlit liquid crystal displays have been developed, and color televisions combined with color filters have become commercially available. In addition to being thinner and lighter than cathode ray tube displays, the flat display described above also has the advantage of displaying information in an XY matrix, making it easy to see, especially in the case of still images, without blur or flickering.

Considering the above-mentioned characteristics needs for displays for information processing terminals and the current state of electronic display devices, it is a self-luminous device with high luminous efficiency that has high contrast and high color rendering properties comparable to cathode ray tube displays, and is as thin as color liquid crystal displays. There is a need for a new display device that is lightweight and easy to see.

It is an object of the present invention to overcome the above-mentioned drawbacks of current display devices and to disclose a novel device that combines the advantages of cathode ray tube displays and flat panel displays.

[Means for solving problems]

In order to achieve this object, the present invention provides an optical shutter layer close to the upper or lower surface of the photoexcitation phosphor layer that is excited by ultraviolet rays of a constant intensity irradiated from the lower surface side, and the optical shutter layer is configured to provide predetermined information. Disclosed is a planar light emitting device that is driven by a signal to control the intensity of light emitted from the photoexcitation phosphor layer and displays it externally as a light image. In order to make the planar light emitting device a liquid crystal display with a backlight and a thin structure, a thin light scattering chamber is provided on the lower surface side of the light excitation phosphor layer, and a straight tube ultraviolet lamp is arranged on the side surface of the planar light emitting device. The device structure may be such that the excitation light emitted from the phosphor layer is once guided to the light scattering chamber to become scattered light of uniform density, and the scattered light excites the phosphor layer located above.

[Effect]

In the present invention, the intensity of light emitted from the phosphor layer is controlled by controlling the optical shutter layer.

〔Example〕

FIG. 1 shows an external view of a planar light emitting device of the present invention. The planar light emitting device has a structure in which a planar light emitting layer 1 and a light irradiation section 2 are laminated. The light irradiation section 2 includes an excitation light scattering chamber 11 and straight tube-shaped ultraviolet excitation light sources 3 and 4. On the planar light emitting layer 1 side of the excitation light scattering chamber 11, R, G, and B phosphor layers partitioned by a black matrix are arranged, and excitation light sources 3, 4 are arranged.
The emitted ultraviolet rays collide with the R, G, and B phosphor layers, causing the entire surface of the phosphor layers to fluoresce.

The planar light emitting layer 1 includes all RoG and B on the phosphor layer.
The optical shutter layer has a one-to-one correspondence with each layer.

For example, if the number of R, G, B is nXm, the light shutter layer has nXm individual light shutter layers.

The individual optical shutter layers are switched one after another by the horizontal and vertical synchronizing signals S, and transmit an amount of light corresponding to the magnitude of the video signal (gradation signal). Therefore, R, G of the phosphor layer
, B dots are selected one after another by the individual shutter layers, and planar light is emitted from the upper surface of the planar light emitting layer 1.

Here, the video signal is an image signal that constitutes a video screen. The size of one video screen corresponds to the size of the planar light emitting layer 1. However, it may be smaller than the planar light emitting layer 1. The size of the video screen and the size of the planar light-emitting layer 1 are determined depending on what is to be displayed and the display format.

FIG. 2 shows an external view of only the light irradiation section 2 taken out from the drawing. The excitation light scattering chamber 2 is hollow, and excitation light sources 3 and 4 are attached to both sides. The excitation light source 3°4 is connected to the socket 7
．． Excite the ultraviolet light sources 5 and 6 under voltage application from 8;
Generates ultraviolet light. This ultraviolet light is transmitted through condensing lenses 9 and 1
1 and enters the scattering chamber 11. In the scattering chamber 11, the ultraviolet light is scattered and collides with the phosphor layer, causing R, G, B
Fluorescence is generated from each dot. This fluorescence is selected by the shutter function in the planar light emitting layer 1 and becomes a planar light emitting source.

The planar light-emitting layer 1 has a liquid crystal layer therein, and is transparent or opaque depending on the voltage applied to the liquid crystal layer. There are many gradation states between transparent and opaque.

This selection becomes the shutter function.

FIG. 3 shows a diagram of the operating principle of the individual planar light emitting layers of the planar light emitting layer 1. The individual planar light emitting layers IA are R, G.

The switch 12 is set to N by the synchronizing signal S, and the video signal Vin at that time is applied to the individual planar light emitting layer IA. The video signal Vin is a one-dot video signal and has multiple gradations.

Incidentally, the planar light emitting layer 1 has nXm individual planar light emitting layers, which are formed in a matrix, and scanning is successively switched by the synchronization signal S.

Specific examples will be shown below.

[Example 1] A 5-inch image display light emitting display device was constructed as follows. That is, as shown in FIG. 4, this display device includes an excitation light scattering chamber 11, a color phosphor layer 30. A rectangular display face plate having a structure in which a liquid crystal light shutter layer (planar light emitting layer) 1 is laminated in this order, and linear excitation light sources 3 and 4 provided in close contact with a pair of opposing parallel side walls of the excitation light scattering chamber. It consists of The rectangular display face plate has an outer periphery made of glass and measures 3.5 (inches) x 4.5 (inches).
X O,a (thickness in inches). The display area is 3 (inches) x 4 (inches). In the excitation light scattering chamber, the walls to which the linear excitation light sources 3 and 4 are in close contact are covered with condensing lenses 9 and 10, and the top surface is covered with a glass substrate 19 coated with a color phosphor layer 30 on the inside, and the other three The wall surfaces (two side surfaces and the bottom surface) are constituted by a hollow rectangular parallelepiped covered with a glass plate 15 on which an aluminum reflective thin film 16 is deposited on the inside, and the inside is in a vacuum state. On the other hand, the color phosphor layer 30 is composed of island-like phosphor regions 18 coated on the transparent glass substrate 19 and non-luminous black tomatrix regions 17 that partition each phosphor layer. The width of the non-luminescent black matrix is 50 μm in the vertical direction (3 inches long) and 50 μm in the horizontal direction (4 inches long).
inch) 40 μm and is formed by screen printing of carbon paste. After forming the black matrix, island-shaped phosphor regions 18 are formed using a mask pattern, and are R (red) for full color display.

G (green) and B (blue) color phosphors are arranged in the pattern shown in FIG. The R, G, and B phosphors each use well-known fluorescent materials, such as Y2O28:Eu for red, Zn2Si○4:Mn for green, and BaMgzA Q+a for blue.
Oz7: Eu is used. The area of each phosphor layer (segment) is 200 μm (vertical direction) x 250 μm (horizontal direction). The portion of the glass substrate 19 protruding from the display surface (3 inches x 4 inches) has a thickness of approximately 5 mm as shown in FIG.
It has a folded shape of mm, and the inner surface of the folded part is made opaque by sandblasting. This portion becomes a ceiling support portion of the hollow excitation light scattering chamber 11 described above, and is welded to the outer wall glass of the excitation light scattering chamber 11.

Therefore, the island-shaped phosphor layer 18 is in a state of hanging down in the vacuum.

In Figure 5, R, G, and B are arranged regularly, and R,
Similarly, blank areas where G and B are not displayed are R and G.

B is placed.

Now, the liquid crystal light shutter area 1 is the transparent glass substrate 19.
A liquid crystal alignment film 26. is formed on the ITO film 2 film 0 formed on the back surface of the liquid crystal alignment film 26. Liquid crystal layer 28. Upper liquid crystal alignment film 22. Spacer 21. Upper part I to which the upper liquid crystal alignment film 22 is in close contact
TO film 23. and a TFT (thin film transistor) drive display electrode region 25. This area has a shutter function that flips the liquid crystal from transparent to opaque. That is, the shutter is placed on two ITO films 02 with the liquid crystal layer 28 sandwiched therebetween.
By arranging only the upper IT○ film (display electrode) 23 of 3 in an island-like matrix as shown in FIG. Fluorescent light is transmitted from below, providing a full-color display. Since the time in the "open" state is controlled, halftone display is of course possible. The area of the island-shaped display electrode 23 is 21
0 μm (horizontal direction) x 160 μm (vertical direction),
The spacing is 40 μm in the horizontal direction and 35 μm in the vertical direction.

TPT is used to apply a voltage to the display electrode 23 for a period of time commensurate with the signal. For example, amorphous hydrogenated silicon (a
-3i:H) can be used. The arrangement of the upper ITO film (display electrode) 23 and the TFT 34 is in a matrix as shown in FIG. 6, and further includes a drain electrode line 31 extending vertically and a gate electrode line 32 extending horizontally. Details of the TPT 34 and the IT○ film 23 are shown in FIG. Each island-shaped display electrode 23 is connected via a source electrode 33 to a TFT 34 arranged at the lower left corner. As shown in the figure, in the space between the island-like display electrodes 23, there are drain electrode lines 31 (15 μm width) of the TFT 34 in the vertical direction, and TPT lines 31 (width 15 μm) in the horizontal direction.
A gate electrode line 32 (15 μm width) is running.

As shown in FIG. 8, such a TPT drive display electrode region 25 is formed by first forming an Au-Cr gate electrode line 32 on a glass substrate 24, and then forming a Si3N4 gate electrode line 32 on top of this using a mask method.
Insulating film 35. T F Ta2 (a-Si: H
) is formed in a vapor phase, and after etching, the drain electrode wire 3 of AQ is formed.
The 1.degree. source electrode 33 is formed by a vapor deposition method, and finally the island-shaped display electrode (upper ITO film) 23 of the above size is formed by a mask method to complete the process. An upper liquid crystal alignment film 22 is applied thereon, and a liquid crystal layer 28 is disposed between it and the lower liquid crystal alignment film 26 with spacers 21 interposed therebetween, facing downward. The pattern of the island-shaped display electrodes 23 is the same as the pattern of the island-shaped color phosphor regions 18, so if they are adjusted so that they match in the vertical direction (so that the optical shutter and the phosphor regions overlap), a rectangular display can be obtained. The face plate is completed. This face plate (5 inches)
The display has 500 x 666 picture elements and an aperture ratio of about 80%.

As a liquid crystal, for example, EBBA (p
A 2=3 mixture of -ethoxybenzylidene-/-n-butylaniline) and MBBA (p-methoxybenzylidene-/-n-butylaniline) can be used.

Next, the linear excitation light sources 3 and 4 for the phosphor layer are connected to condensing lenses 9 and 1.
A metal light-reflecting outer cover that adheres to the 0, and an ultraviolet light lamp, socket, and lead wire placed inside it.

It consists of a power supply, a switch (partially shown in Figure 2), etc. The inner glass plate 15 of the light-reflecting outer cover increases the light reflectance.
It is covered with an AQ vapor deposited film 16. The ultraviolet lamp is a low-pressure mercury lamp (main emission wavelength 254 nm). The socket is used to apply voltage to the ultraviolet light lamp and to hold it in place to prevent ultraviolet light from leaking to the outside. Therefore, when the ultraviolet lamp is turned on, almost all of the emitted ultraviolet light (excitation light of the phosphor) is introduced into the excitation light scattering chamber 11 via the condenser lenses 9 and 10.

Now, when this surface emitting display device is connected to an image display power source (not shown) and turned on, a signal voltage is applied to the liquid crystal light shutter area of the rectangular display panel. As for the signal voltage, a gate signal S synchronized with the horizontal line of the television is applied to the gate electrode line 32 of the TPT, and line-sequential scanning is repeated. Further, an inverted video signal voltage Vin (a negative signal voltage obtained by inverting a strong video signal to a weak video signal) corresponding to each point is applied to the drain electrode line 31. This is because the dynamic scattering mode liquid crystal becomes opaque (shows a shutter effect) when a voltage is applied. When the source/drain voltage of each TFT34 is 2.8V, when the gate voltage is switched from Ov to 15V, the drain current is 1O-12A.
Changes by 6 digits from to 10-' A, with sufficient 0N10FF
An extremely vivid television image (frame frequency 60 Hz) is obtained to demonstrate the characteristics.

This equivalent circuit is shown in FIG.

The luminous efficiency (electricity → light energy conversion efficiency) of this surface emitting display device is when the entire surface is illuminated (no image display)
0.1-0.3% for image display reaching 12-20%)
, 2-3% for color cathode ray tubes, 0.5-1.5% for color LCD TVs (without image display) (0.
(approximately 0.01%). In addition, the beauty and vividness of an image are determined by the number of color cathode rays, weight, thinness,
The ease of viewing was shown to be on par with that of a color LCD TV.

[Example 2] A monochrome character display panel (80 characters x 25 lines) with a display area of 224 x 98 ny'' was constructed by employing a time-division drive liquid crystal matrix optical shutter. In other words, this device
As shown in FIG. 10, a pair of straight tube-shaped ultraviolet excitation light sources 3 and 4 are arranged along the long side edges of a rectangular substrate, and time-divisionally driven liquid crystal matrix light is applied onto the upper glass substrate 19 of a vacuum region (excitation light scattering chamber) 11. It has a structure in which a shutter IA is arranged, and a monochromatic phosphor layer 43 and an upper protective glass substrate 24 are further laminated on top of the shutter IA. As in the previous embodiment, the excitation light scattering chamber 11 includes condensing lenses 9, 10, .
The portion other than the upper glass substrate 19 is composed of a glass plate 15 with an AQ light reflection film 16 deposited on its inner surface, and the inside is kept in a vacuum to avoid absorption of ultraviolet rays.

A light deflection plate 45 is closely attached to the lower surface of the upper glass substrate 19. On the other hand, on the upper surface of the upper glass substrate 19, a striped IT○ film 50. A oriented film 51 is adhered thereto, and a twisted nematic liquid crystal 53 having a thickness of approximately 10 μm and having positive dielectric anisotropy is sealed through a spacer 52 . The upper liquid crystal electrode 54 is made of a striped TO film orthogonal to the striped ITO film 50 . A liquid crystal alignment film 55 is applied to the ITO film 54 . striped IT
Although the O film 54 is formed directly on the transparent glass plate 40,
The surface of the transparent glass plate 40 and the transparent glass plate 42 above it
An upper light deflection plate 41 whose polarization plane is in the same direction as the lower light deflection plate 45 is disposed in close contact therebetween. Transparent glass plate 42
On the upper surface, a monochromatic phosphor layer 43 with a thickness of approximately 20 μm is formed.
2SiO5:Ce and Tb are coated. An upper protective glass layer 48 is arranged on the upper surface of the monochromatic phosphor layer 43, but in order to keep the phosphor layer 43 stable for a long period of time, it is desirable that this layer be sealed in a vacuum state. .

Upper and lower striped IT○ films 5 sandwiching the liquid crystal layer 53
0.54 constitutes an XY matrix that is orthogonal to each other, and
By applying a scanning signal voltage to the axial stripe electrode 54 and a display signal voltage to the Y-axis stripe electrode 50 in the form of alternating current pulses, each display point is provided with an optical shutter function. That is, the excitation light scattering chamber 1
The linearly polarized excitation light that has passed through the polarizing plate 45 via the substrate glass 19 from 1 enters the liquid crystal 53, but if no threshold voltage is applied to the intersection of the XY stripe electrodes, the plane of polarization changes as it advances. It rotates according to the twist, reaches the upper alignment film 55, and rotates 90 degrees, so that
The light passing through the glass plate 40 is blocked by the upper polarizing plate 41 and cannot enter the phosphor layer 43. Therefore, no light emission is observed in this case. However, when a voltage higher than the threshold is applied to the intersection of the l6-XY stripe electrodes, the liquid crystal aligns perpendicularly to the electrode plane, so
The excitation light that has passed through the polarizing plate 45 is directed to the liquid crystal 53 → alignment film 55 →
The light passes through the IT◯ film 54 → the glass plate 40 → the upper polarizing plate 41, and excites the corresponding part of the phosphor layer 43 disposed above it in a dotted manner. Therefore, in this case, a green body is displayed externally. In this example, the number of X-axis stripe electrodes is 100 (0.5+nm width), that is, the duty ratio is 1/100.
A good result was obtained with a contrast ratio of 20:1. When a character display panel of the same size is configured with only a liquid crystal optical shutter (non-luminous display) without using a phosphor layer as in this example (duty ratio 1/100), the contrast ratio is 8:1, It was clearly shown that the device of this example was superior in terms of "ease of viewing."

On the other hand, in order to compare the electrical to light energy conversion efficiency, 1. white light was irradiated from the back side of the non-luminescent character display panel of the same size. That is, in FIG. 10, the monochromatic phosphor layer 43. The upper protective glass layer 48 was removed, and a display device (so-called backlit liquid crystal device) was constructed in which white fluorescent lamps with excellent color rendering properties were arranged at the positions of the ultraviolet excitation light sources 3 and 4. When the same display pattern as that of the display device of FIG. 10 was displayed and the electrical to light energy conversion efficiency was compared, it was found that the display device of FIG. 10 of the present invention was about 40% higher than the above-mentioned backlit liquid crystal device. This is thought to be mainly due to the difference in ultraviolet excitation efficiency between the two device phosphors (the difference between the excitation efficiency of the high color rendering white phosphor and the excitation efficiency of the green phosphor).

However, when the monochrome display device of this example was compared with the color display device of the present invention of the previous example in terms of efficiency, it was found that the efficiency of the previous example was about one order of magnitude higher. This is because, in the case of this embodiment, polarizing plates are provided before and after the liquid crystal light shutter to allow only linearly polarized light to pass through. In other words, it is important to employ a non-polarized light shutter for highly efficient driving.

[Example 3] Display area 50 x 10 in 5 x 7 segment matrix display
0! I made a number/character display device for In2. In this case, the optical shutter is a peptylviologen-based electrochromic display (ECD). Although the peptyl viologen aqueous solution used as the ECD material is an organic substance, it becomes colored purple when a reduction reaction occurs due to voltage application. The writing time is approximately 20 m5 ec with 1 V applied and the distance from the counter electrode (anode) to approximately 1 plate.

Erasing is performed by applying a reverse voltage of 1 V for about 25 m5ec. Also, when colored, the absorbance for 254 nm ultraviolet rays is approximately 90%.
becomes. As shown in Figure 11, three ultraviolet lamps (straight tube 10W) 60 are lined up in the longitudinal direction of the display device to fluoresce.
゛The light body layer is an excitation light source, with a reflective metal film 1 on the back side.
6 is deposited on the glass substrate 15. A dot-patterned NESA film 61 is formed on the upper surface of the transparent glass substrate 19 above the excitation light source.
On the top is a dot corresponding to the display point (diameter 2+nmφ).

An opaque insulating film 62 having through holes with a pitch of 0.5 mm is formed by screen printing. This through hole (
A peptyl viologen aqueous solution 63 is filled to a depth of approximately 1 nwn. Next, a transparent IrO2 film 65 is deposited as a counter electrode on the lower surface of the transparent glass plate 64, and the IrO2 film is fixed in contact with the peptyl viologen aqueous solution.
The aqueous solution 63 is applied to the glass plates 19 and 64. and is sealed by a spacer 52. On the upper surface of the transparent glass plate 64, Y2O3:'Eu was applied as a phosphor layer 70 to a thickness of about 30 μm, and the upper surface was sealed with a protective glass plate 48.

The number and character display device is driven as follows.

First, when a DC voltage of about 1.2 V is applied to an aqueous peptyl viologen solution with the IrO2 film 65 plus the NESA membrane 61 and the NESA membrane 61 in the form of 1 minus, the aqueous solution is colored purple by a reduction reaction. If you leave this coloring as it is, it will last about a month.
Even if the phosphor layer excitation light source (ultraviolet lamp) 60 is turned on in this state, only a few percent of the ultraviolet light will pass through the ECD layer, so Y2O3:E
The excitation emission intensity of the U layer 70 is extremely weak, and the ECD optical shutter is in the state of "○FFJ."Next, only the NESA film dot electrode 61 to be displayed as numbers and letters is made positive, and the entire Ir○2 film 65 is turned on. Approximately 1.1 as 65 total minus
When a DC voltage of v is applied, an oxidation reaction occurs only in the peptyl viologen aqueous solution region corresponding to the dot electrode 61, and the aqueous solution region becomes transparent in about 25 m5 ec. As a result, the 254 nm ultraviolet rays emitted from the excitation light source 60 pass through the transparent region and efficiently <Y2O3:Eu phosphor layer 70.
The corresponding region of the dot can be excited, and red light (λ=611 nm) corresponding to the display dot is emitted to the outside. That is, this state is the rONJ state of the ECD optical shutter. “○NJ” of these peptyl viologen aqueous solutions
Since the voltage application corresponding to rOFFJ can be performed with a single rectangular wave pulse of about 30 m5ec, the display contents can be changed one after another as necessary. The numbers and characters displayed by this display device have a high contrast (contrast ratio 30:1) because they are a red light emitting pattern on a black-purple background, and the display effect is extremely large.In principle, the rONJ voltage value of this ECD optical shutter or Although it is possible to display halftones by controlling the pulse width, it is difficult to display clear gradations with the liquid crystal optical shutter of the previous embodiment. However, as mentioned above, the coloring memory of the aqueous peptyl viologen solution lasts for up to one month, so it can also be used as a fixed number/character display.

〔Effect of the invention〕

As described in detail above, the present invention uses a combination of optically excited fluorescence (photoluminescence) and an electronic optical shutter to access the display point and adjust the gradation using the optical shutter, resulting in high contrast.

A highly efficient planar display device in which a photoexcitable phosphor is used to provide high visibility based on high color rendering properties has been disclosed.

To summarize the features of the planar light emitting device of the present invention, (1) it is a thin and lightweight high-definition display device, (2) it has a high contrast ratio and excellent visibility, and (3) it has high luminous efficiency and therefore low power consumption. (4) It can be made into a portable device because it can be driven at low voltage, and (5) It is cost-effective as well as other luminescent flat displays (light-emitting diodes, electroluminescent devices, plasma display devices, fluorescent display tube devices, etc.). Can be manufactured more cheaply (for large capacity display devices)
This shows that this is a display device for information processing terminals that has high performance display comparable to that of a cathode ray tube and light weight comparable to a liquid crystal display device.

In this embodiment, a case has been described in which a liquid crystal and an ECD are used as the optical shutter, but it is obvious that it is also possible in principle to use, for example, an electrophoretic effect or an electro-optical effect of a dielectric material.

[Brief explanation of the drawing]

FIG. 1 is an external view of the surface emitting device of the present invention, FIG. 2 is an external view of the light irradiation part, and FIG. 3 is an explanatory diagram of the operation of the individual optical shutter.
FIG. 4 is a device structure diagram in one embodiment of the present invention, FIG. 5 is a layout diagram of phosphor layers, and FIGS. 6, 7, and 8 are liquid crystal drive parts in the device shown in FIG. 4. 9 is an equivalent circuit diagram, FIG. 10 is a diagram showing the main parts of a device structure in another embodiment of the present invention, and FIG. 11 is a diagram showing the main structure of the device.
The figure is a diagram of the main parts of a device structure in yet another embodiment of the present invention. In the figure, 15 is a glass plate on the lower side of the excitation light scattering chamber. 16 is a metal reflective film, and 9.10 is a lens for condensing excitation light. 19 is a glass plate on the upper side of the excitation light scattering chamber, 18 is an island-like phosphor region, and 20 is a lower ITO film (lower transparent electrode). 26 is a lower liquid crystal alignment film, 28 is a liquid crystal, 22 is an upper liquid crystal alignment film, 21 is a spacer, 23 is an upper ITO film (upper transparent electrode), 25 is a TPT drive display electrode area, 3 and 4 are straight tube ultraviolet excitation light sources , 43 is a monochromatic phosphor layer, 24° 48 is an upper protective glass plate of the display device, 45 is a lower light deflection plate, 41 is an upper light deflection destination plate, 42 is a transparent glass plate, 62 is an opaque insulating film, 63 is a peptide Rubiologen aqueous solution, 65
indicates an IrO2 counter electrode, and 17 indicates a non-luminous black matrix region. Patent applicant: Polytronics Co., Ltd. Patent attorney Masami Akimoto (1 other person) Figure 7 Figure 8 Mr+ Figure 10 Figure 11

Claims (1)

[Claims] 1. An optical shutter layer is provided in close proximity to the upper or lower surface of a photoexcitation phosphor layer that is excited by ultraviolet rays of a constant intensity irradiated from the lower surface side, and the optical shutter layer is driven by a predetermined information signal. A planar light-emitting device that controls the intensity of light emitted from the photoexcitation phosphor layer and displays it externally as a light image. 2. A planar light emitting device according to claim 1, wherein the optical shutter layer is an XY matrix liquid crystal shutter. 3. In the planar light emitting device according to claim 1, as a means for irradiating the photoexcitation phosphor layer with ultraviolet rays of a constant intensity, straight tubes are provided on a pair of parallel two opposing sides of the rectangular display face plate. Ultraviolet lamp light sources are arranged in close contact with each other, and emitted ultraviolet light is first introduced into a rectangular parallelepiped light scattering chamber provided on the lower surface side of the light excitation phosphor layer, and then the light excitation phosphor layer is irradiated and excited with the scattered light. A planar light emitting device characterized by having an ultraviolet scattering region.