JPH04323686A - Display device - Google Patents

Abstract

PURPOSE:To provide the display device which is of a self-light emission type and can make display to a larger screen. CONSTITUTION:Phosphors (b) which emit red, green and blue photoluminescence lights are orderly disposed as picture element units on a transparent or semitransparent substrate (a). The laser beam from a laser excitation light source (c) is intensity modulated by the brightness signals in image signals by an optical modulating element (d) and the intensity modulated laser beam is direction modulated by an optical modulating element (e) so as to coincide with the red, green and blue image signals. The phosphors generate the photoluminescence light of the intensity depending on the irradiation intensity if the respective phosphors (b) are irradiated with the laser beam intensity modulated and direction modulated in such a manner. The large-sized display picture elements which make self-light emission of three primary colors; red, green and blue, are obtd. without using the members, such as vacuum tubes, requiring vacuum in such a manner.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device using a phosphor that emits photoluminescence light.

0002

BACKGROUND OF THE INVENTION Research and development on large-sized display devices is being carried out in various fields, but various problems have arisen as the devices become larger. Typical display elements used in displays include: (1) CRT (cathode ray tube) (2) VFD (fluorescent display tube) (3) PDP (plasma display panel) (4) L
CD (liquid crystal display element) (5) EL (electroluminescence) (6) LED (
light emitting diode), etc.

0003

[Problem to be solved by the invention] Among the above display elements,
The display elements (1), (2), and (3) require a vacuum, so it is difficult to make them large; the display elements (5) and (6) are blue light-emitting elements that are still under development; ) display elements are not self-luminous, so visibility is only a step up, so there is no definitive answer.

0004

OBJECTS OF THE INVENTION An object of the present invention is to provide a display device that is self-luminous and can have a large screen by changing the conventional method using display elements.

[0005]

[Means for Solving the Problems] A display device according to the present invention includes a transparent or translucent substrate on which each phosphor pixel that emits red, green, and blue photoluminescent light is arranged; A laser excitation light source that emits laser light; a first light modulation element that modulates the intensity of the laser light according to a luminance signal in an image signal; and a first light modulation element that modulates the intensity of the laser light using a luminance signal in an image signal; and a second light modulation element that irradiates the substrate with laser light, with the irradiation direction determined so as to match the irradiation direction.

[0006]

[Operation] In the display device configured as described above, the laser light emitted from the laser excitation light source is first intensity-modulated by the first light modulation element according to the luminance signal in the image signal, and then the laser light is intensity-modulated by the second light modulation element. The irradiation direction of the laser beam is determined so as to match the red, green, and blue pixel signals in the video signal. When each of the red, green, and blue phosphors is irradiated with laser light, the phosphors generate photoluminescence light whose intensity depends on the irradiation intensity.

[0007]

Embodiment FIG. 1 shows an embodiment of the present invention. In the figure, (a) is a transparent or semi-transparent substrate, and red (abbreviated as R), green (abbreviated as G), and blue (abbreviated as B) photoluminescence light is applied to this substrate (a). The emitting phosphors (b) are arranged in an orderly manner. (c) is a laser excitation light source, (d) is a light modulation element that modulates the intensity of the laser light according to the luminance signal in the pixel signal, and (e) shows the intensity-modulated laser light as an RGB image signal in the video signal. This is a light modulation element that determines the direction of laser light irradiation. (f) is a laser beam modulated so that it enters the phosphor, (g) is a phosphor emitting photoluminescence light, and (h) is a laser beam that is modulated so that it leaves the phosphor. It is.

According to the above configuration, the laser light emitted from the laser excitation light source is first intensity-modulated by the light modulation element (d) using the luminance signal in the image signal. Next, the direction of irradiation of the laser beam is determined by the light modulation element (e) so as to match the RGB pixel signals in the video signal. When each of the RGB phosphors is irradiated with laser light, the phosphors generate photoluminescence light whose intensity depends on the irradiation intensity.

[0009] Differences in emission intensity between RGB phosphors and differences in human color sensitivity can be realized not only by changing the intensity of the laser light but also by changing the size of each RGB phosphor unit pixel. It is. When irradiating each RGB phosphor with laser light, there are two methods: directly irradiating each RGB phosphor with laser light based on the video signal, and irradiating two RGB phosphors with complementary colors. It is also possible to do so.

FIG. 2 shows an example in which the present invention is applied to a large display. In the figure, (a) is a base consisting of RGB phosphor unit pixels, (c) is a laser excitation light source,
An element including an intensity modulation light modulation element (d) and a direction modulation light modulation element (e), (i) a video signal processing device, (j
) is the optical system reflecting mirror.

According to the above configuration, the laser excitation light source (c
) The laser beam irradiated from the video signal processing device (i
), the light modulation elements (d) and (e) perform intensity modulation and direction modulation. If the modulation ability of the light modulation element for directional modulation is small, it is possible to use a suitable aspherical reflection mirror (j) so that the laser light can be irradiated onto the entire substrate consisting of each unit pixel of the RGB phosphor. can.

0012

[Effects of the Invention] As described above, according to the present invention,
Without using parts that require vacuum such as vacuum tubes,
It is possible to realize a large display screen that self-lights the three primary colors of RGB.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a display device showing a basic embodiment of the present invention.

FIG. 2 is a configuration diagram of a display device according to an example in which the present invention is implemented in a large display.

[Explanation of symbols]

a Transparent or semi-transparent substrate b RGB phosphors c Laser excitation light source d Intensity modulation light modulation element e Directional modulation light modulation element f Laser light incident on the phosphor h Incident on a portion away from the phosphor laser light i
Video signal processing device j Reflection mirror

Claims (1)

[Claims] 1. A transparent or translucent substrate on which each phosphor pixel that emits red, green, and blue photoluminescent light is arranged, a laser excitation light source that irradiates laser light, and an image. a first light modulation element that modulates the intensity of the laser light according to a luminance signal in the signal; and determining an irradiation direction of the intensity-modulated laser light so as to match the red, green, and blue pixel signals in the video signal; and a second light modulation element that irradiates the base with laser light.