JPH03113484A - Display device - Google Patents

Abstract

PURPOSE:To increase the degree of freedom in design of structure and shape, etc., of screen and to obtain a high level of brightness by transforming laser beam of a large output to ultra violet ray, and irradiating a phosphor layer on a screen freely scannable with this ultra violet ray. CONSTITUTION:The laser beam 2a outputted from a laser beam source 2 which is continously oscillated is transformed to, for example, the ultra violet ray 3a of a specified wave length by a transformer 3 consisting of non linear optical crystals, etc. This ultra violet ray 3a is allowed to irradiate freely scannable the phosphor layer 6 of a dot matrix state of the screen 5 at a scanning device 4, and scanning is carried out to plot a desired image. In this way the screen 5 is separated from the scanning device 4. Thus, the degree of freedom in the design in manufacture or shape, etc., of the screen is increased and a high level of brightness in an image can be obtained.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a display device that has a completely different display principle from conventional CRTs (cathode ray tubes), liquid crystal displays, etc. The present invention relates to a display device that can both increase the size of the screen for displaying graphics, graphics, etc., and separate the screen from the device body.

(Prior Art) Conventionally, an example of a well-known display device is the sixth display device.
There is a C-CRT (color cathode ray tube) shown in the figure, which is widely used in both consumer and industrial applications due to its advantages such as high image quality and high resolution.

As shown in FIG. 6, this CRTl has red, green, blue (R, G,
B) Three types of phosphor films 4 that emit light are deposited in a dot matrix, and an electron beam 6 is irradiated onto the phosphor film 4 from an electron gun 5 built in the vacuum glass container 2. This electron beam 6 is deflected and scanned by a deflection coil 7 to draw an image on the face plate 3.

(Problem to be solved by the invention) However, in such a conventional CRTI, the electron gun 5
In order to irradiate the phosphor film 4 with the electron beam 6, a vacuum atmosphere is required as the electron beam irradiation path, and a heavy vacuum glass container 2 is indispensable, resulting in an increase in weight.

Furthermore, since the face plate 3, the electron gun 5, the deflection coil 7, etc. need to be constructed integrally with the vacuum glass container 2, the weight of the whole is increased, and the face plate 3
It is also impossible to separate the vacuum glass container 2 from the vacuum glass container 2 to increase its size or to freely change its shape. Furthermore, the brightness on the face plate 3 is not necessarily sufficient.

Therefore, the present invention was made in consideration of these circumstances, and its purpose is to significantly increase the size of the screen that displays images such as characters and figures, and to make it possible to separate only the screen from the device body and to achieve high brightness. Our goal is to provide display devices.

[Structure of the invention]

(Means for Solving the Problems) The present invention has been made by focusing on the large power of laser light, and the principle thereof will next be explained based on FIG. 1.

The display device 1 of the present invention converts laser light 2a outputted from a continuously oscillating laser light source 2 into ultraviolet rays 3a of a desired wavelength by a converter 3 made of, for example, a nonlinear optical crystal.
Convert to

The ultraviolet rays 3a are irradiated onto the dot matrix-shaped phosphor layer 6 of the screen 5 in a scannable manner by a scanning device 4, and the ultraviolet rays 3a are scanned to draw a desired image.

(Function) Laser light 2a output from laser light source 2 is converted into ultraviolet light 3a by converter 3. This is because the phosphor layer 6 of the screen 5 is excited by the ultraviolet light 3a and emits light, but does not emit light by the laser light 2a.

This ultraviolet ray 3a is irradiated onto the phosphor layer 6 of the screen 5 by the scanning device 4 and scanned.

Therefore, the light-receiving portion of the phosphor layer 6 irradiated with the ultraviolet rays 3a emits light, and emits light sequentially in accordance with the scanning, thereby displaying a desired image.

Therefore, according to the invention, the screen 5 is a conventional C.
Unlike the RT, it does not need to be placed in a vacuum atmosphere, and since it is separated from the scanning device, it is possible to individually increase the size of the screen 5 and improve the degree of freedom in shape design. Since the light source is used as a light source, it is possible to increase the brightness of the image.

(Example) Examples of the present invention will be described below based on FIGS. 2 to 5.

The display device 11 according to the first embodiment of the present invention shown in FIG. A converter 13 for converting laser light 12a into ultraviolet light 13a is provided at the end of the laser light emitting port.

This converter 13 is made of K TiOP O4 single crystal or BaB.
Due to the nonlinear optical effect of nonlinear optical crystal such as 2O4 single crystal, laser beam 1 of Nd:YAG laser with a wavelength of 1.064 μm is generated.
2a to the fourth harmonic of 266 nm ultraviolet light 13a.

The ultraviolet rays 13a converted from the laser beam 12a in this way
Optical fiber 1 may pose a danger to the human body.
3f and is transferred to the scanning device 14.

The scanning device 14 irradiates the screen 15 with ultraviolet rays 13a from an optical fiber 13f and scans the screen 15 vertically and horizontally, and has a galvanometer mirror that scans the ultraviolet rays 13a vertically and horizontally, respectively.

The galvanomirror has rotating polygon mirrors for horizontal scanning and vertical scanning, for example, a 24-sided rotating polygon mirror that can rotate at 7000 rpm for horizontal scanning, and a 12-sided rotating polygon mirror for vertical scanning. 30 orp with mirror
A rotatable one was used.

On the other hand, the screen 15 has a screen base 15a made of a flat plate of transparent glass measuring, for example, 2 m in length and 4 m in width, and has three types of fluorescent light emitting red, green, and blue (R, G, B) on the back side. A large number of pairs are formed by a pair of phosphors coated in a dot matrix pattern.

For example, the phosphor layer 16 may include 3 as a red (R) emitting phosphor.
Yttrium oxide activated with valent europium, lanthanum phosphate activated with cerium and terbium as the green (G) emitting phosphor, and barium oxide activated with divalent europium as the blue (B) emitting phosphor. Magnesium alumina-1 was used.

Further, a shutter device main body 17 is attached to the front surface of the screen base 15a, and the refractive index of the entire light transmitted through the shutter device main body 17 can be adjusted to be concave or concave depending on the electric field applied by the voltage control device 18. It is controlled like a convex lens.

The shutter device main body 17 has a pair of upper and lower polarizer films 17b on both sides of the shutter element 17a.

1' 7 c, so as to align the direction of the person and the emitted light to the shutter element 17a.

The shutter element 17a is constructed as shown in FIG. 3, and the transparent plate 17d, which transmits the ultraviolet rays 13a from the converter 13 in the front and back directions, is made of an electro-optic material having an electro-optic effect, such as transparent PLZT electro-optic ceramics. It is formed into a transparent plate using a material.

Further, on one side of the front and back sides of the light-transmitting plate 17d, a pair of an anode 17e and a cathode 17f, which are transparently formed of, for example, an ITO film or a NESA film, are provided, with a minute gap in the width direction of the light-transmitting plate 'L7d. Paste these positive and negative electrodes 17e and 17f.
A plurality of pairs are arranged in parallel at a required pitch in the width direction of the transparent plate 17d.

These multiple pairs of positive and negative electrodes 17e and 17f are connected to the voltage control device 1.
8, respectively.

The voltage control device 18 supplies a constant voltage (■) to a plurality of voltage dividing resistors RO to R.
7, respectively, and the positive and negative electrodes 17e.

The voltage applied between 17f is controlled for each electrode pair.

For this reason, the refractive index distributed in each space between the multiple pairs of positive and negative electrodes 17e and 17f is the same as that of each corner and the negative electrode 17e.

Depending on the applied voltage of 17f, that is, the applied electric field, the concave or convex lens shape is controlled, and the focal length is controlled.

Therefore, the voltage control device 18 causes the shutter element 17 to
By controlling the voltage applied between the plurality of pairs of transparent electrodes a for each pair of electrodes, the refractive index of the transmitted light transmitted between the electrodes on this shutter element 17a is appropriately controlled. The focal length of the image is controlled, and the contrast of the image is continuously controlled.

Therefore, for those viewing the screen 15, if the focus is not narrowed, the image will be unclear, and the clarity can be controlled by voltage control of the voltage control device 18.

Next, the operation of this embodiment will be explained.

Laser light 12a continuously oscillated by laser light source 12 is converted into ultraviolet light 13a by the nonlinear optical effect of converter 13 at its laser light emission port.

Since this ultraviolet ray 13a may be harmful to the human body, it is transferred to the scanning device 14 through the optical fiber 13f, where it is irradiated onto the phosphor layer 16 of the screen 15 and scanned.

The phosphor layer 16 sequentially emits light in a desired color in accordance with scanning at the locations where the ultraviolet rays 13a are received, and is irradiated to the outside through the shutter device main body 17 as a desired image.

The shutter device main body 17 controls the voltage applied to the shutter element 17a with a voltage control device 18 as appropriate.
The contrast is appropriately controlled.

Therefore, according to this embodiment, it is not necessary to provide the screen 15 in a vacuum atmosphere, and since it is separated from the scanning device 14, only the screen 15 can be individually made extremely large.

Further, since the laser beam 12a having high power is used as a light source, high brightness can be achieved.

Furthermore, since the shutter element 17a has no mechanically movable parts, it is easy to operate and the occurrence of failures can be reduced.

Moreover, since ultraviolet rays that may be dangerous to the human body are passed through the optical fiber 13f, safety can be improved.

Display device 21 of the second embodiment shown in FIG.
In this example, the converter 13 of the first embodiment is replaced with another converter 22, and the control means 2 consisting of a microcomputer etc.
3 is provided to control the scanning of the scanning device 14. Other than this, the embodiment is almost the same as the first embodiment, so parts in FIG. 3 that are the same as those in FIG. Attached to
The redundant explanation has been omitted.

The converter 22 is a nonlinear optical crystal KTI OP O4.
Both the single crystal 22b and the BaB2O4 single crystal 22c are arranged in parallel at the emission end of the laser beam 12a, and due to the nonlinear optical effect of these nonlinear optical crystals, the wavelength is, for example, 1.0.
The wavelength of the fourth harmonic of the 64 μm laser beam 12a is 2
Converts into 66 nm ultraviolet light 22a.

Furthermore, this ultraviolet ray 22a is e.g.
A bandpass filter 22d is installed to allow only light of m to pass through, and prevent other light from passing through. The light transmittance of the bandpass filter 22d for ultraviolet rays 22a having a wavelength of 266 nm is approximately 70%.

On the other hand, the control means 23 controls the scanning direction of the ultraviolet rays 22 vertically and horizontally by controlling the rotational speeds of the rotating longitudinal mirror for vertical scanning and the rotating lateral mirror for horizontal scanning of the scanning device 14. .

The control means 23 inputs necessary image data, and in order to display the image on the screen 15, the control means 23 sends a pair of both digital control signals to control the on/off, rotation speed, etc. of the vertical and horizontal mirrors, respectively. The signals are supplied to D/A converters 24a and 24b, respectively, where they are converted into analog signals.

Further, both of these analog control signals are amplified into a control signal of a required amplitude by a pair of drive amplifiers 25a and 25b, and the signal is applied to the rotating vertical mirror and the rotating horizontal mirror, respectively, to control their rotational speed, etc. There is.

The display device 31 shown in FIG.
2, an argon ion laser is used, which emits laser light 3 with a wavelength of 514.5 nm and a beam diameter of 4 mmφ.
2a with an output of 5.2 mW, and a nonlinear optical crystal B is installed as a converter at the end of the laser beam emission port.
An aB2O4 single crystal 33 is provided.

BaB204 single crystal 33 is 0. 4545~0°514
60-70% of 5μm laser light due to nonlinear optical effect
High efficiency of 0.2273~0.2573μ of second harmonic
This converts the ultraviolet rays into ultraviolet rays 33a of m.

The ultraviolet rays 33a of this BaB2O4 single crystal 33 are provided with a bandpass filter 34 that allows only light of about 200 to 400 nm to pass through, for example, and prevents other light from passing through. The transmittance of this bandpass filter 34 for transmitting light with a wavelength of 266 nm is approximately 70%.

For example, the ultraviolet ray 33a of 265 nm that has passed the bandpass filter 34 passes through the optical fiber 13f and passes through the scanning device 1.
It is now transferred to 4.

The vertical and horizontal rotation of the scanning device 14 is controlled by a control means 23 consisting of a microcomputer as in the second embodiment.

On the other hand, the arcuate screen 35 is irradiated with ultraviolet rays 33a by the scanning device 14 and scanned by the screen base 3.
5a is made of an arc-shaped transparent plate glass, and a phosphor layer 36 is formed by coating R, G, and B phosphors in a dot matrix on the concave arc-shaped inner surface.

Also in this embodiment, since it is not necessary to provide the arcuate screen 35 in a vacuum atmosphere, only the arcuate screen 35 can be individually enlarged.

Further, since the arc screen 35 is provided separately from the scanning device 14, the arc screen 35 can be provided separately, and the degree of freedom in designing the arc screen 35 can be increased.

Furthermore, since the laser light source 32 is used as a light source, high brightness can be achieved.

Note that the present invention is not limited to the shape of the screens 5, 15, 35, and may be, for example, cylindrical, and is not limited to this shape.

Further, in the above embodiment, the shutter element 17a is equipped with a plurality of pairs of cathodes 17f and anodes 17e, but the second embodiment utilizes the secondary electro-optic effect generated between the pair of electrodes 17e and 17f. Good too.

〔Effect of the invention〕

As explained above, the present invention converts high-output laser light into ultraviolet rays and irradiates the phosphor layer on the screen with the ultraviolet rays in a scanning manner, so there is no need to place the screen in a vacuum atmosphere. Therefore, it is possible to individually increase the size of only the screen, and since only the screen can be separated from the device body, the degree of freedom in designing the structure and shape of the screen can be increased. Since light is used as the light source, high brightness can be achieved.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram for explaining the principle of the display device according to the present invention, FIG. 2 is a configuration diagram showing the overall configuration of the first embodiment of the invention, and FIG. 3 is shown in FIG. Configuration diagram of the shutter device main body and voltage control device, Figures 4 and 5
The figures are configuration diagrams of second and third embodiments of the present invention, and FIG. 6 is a side sectional view of a CRT, which is an example of a conventional display device. 1.11, 21.31...Display device, 2
．． 12.32...Laser light source, 2a, 12a. 32a... Laser light source, 3.13, 22.33...
Transducer, 4, 14...Scanning device, 5, 15.35...
Screen, 5a, 15a, 35a... Screen base, 6.16.36... Phosphor layer, 17... Shutter device main body, 18... Voltage control device.

Claims (1)

[Claims] A screen in which a phosphor layer is formed by coating a phosphor in a dot matrix on a base, a laser light source that outputs laser light, a converter that converts the laser light from this laser light source into ultraviolet light, and this converter. A display device comprising a scanning device that scans and scans the phosphor layer of the screen with ultraviolet rays from the screen.