JP2000305040A - Projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bright display video that color purity of red is high and color reproducibility and white balance are excellent. SOLUTION: A red light emitting diode 30 is arranged at the incident side of a liquid crystal panel for red 22. Then, light from the diode 30 is made incident on the panel 22 through a lens array 32. Besides, a red optical picture from the panel 22 is synthesized with a blue and a green optical pictures by a synthesizing prism 14 and displayed on a screen by a projection lens 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection display device which illuminates a light valve such as a liquid crystal with an illumination optical device and enlarges and projects an image on the light valve onto a screen.

[0002]

2. Description of the Related Art Conventionally, a projection display apparatus has realized a high-luminance display image with high luminous efficiency by using a high-pressure mercury lamp, which has become mainstream in recent years.

In FIG. 5, 1 is a light source (lamp), 2 is a reflector, 3 is a UV filter, 4 is an IR filter,
Reference numerals 5 and 6 denote a first fly-eye lens element and a second fly-eye lens element, each of which is composed of a fly-eye lens. Light from the lamp 1 is emitted to the dichroic mirrors 8, 9, and 10 via the fly-eye lens elements 5, 6 and the lens 7.

The light reflected by the dichroic mirror 8 enters a liquid crystal panel (spatial modulation element) 13 as, for example, a light valve for blue (B) via a mirror 11 and a lens 12. The blue optical image spatially modulated by the liquid crystal panel 13 enters the combining prism 14.

The light transmitted through the dichroic mirror 8 is reflected by the dichroic mirror 9 and enters, for example, a liquid crystal panel (spatial modulation element) 17 as a light valve for green (G) via a lens 16. The green optical image spatially modulated by the liquid crystal panel 17 enters the combining prism 14.

The light transmitted through the dichroic mirror 9 enters the dichroic mirror 10 via the lens 18. The light reflected by the dichroic mirror 10 enters, for example, a liquid crystal panel (spatial modulation element) 22 as a light valve for red (R) via a lens 19, a mirror 20, and a lens 21. The red optical image spatially modulated by the liquid crystal panel 22 enters the combining prism 14.

[0007] The blue, green,
Each of the red optical images is synthesized and enters the projection lens 15 as a full-color optical image. The projection lens 15 projects the incident full-color optical image on a screen.

[0008]

In the above-mentioned projection display device, the chromaticity of each color separated by a dichroic mirror or the like depends on the wavelength distribution of the lamp. Compared to other lamps, the luminous efficiency is high and high luminance can be realized, but there is a problem that the amount of red wavelength component is small and red color reproducibility is difficult.

Further, the brightness largely depends on the amount of green light, and the brightness increases as the amount of green light increases. However, the small amount of red light means that in order to achieve the white balance of the projected image, the amount of light of other color (green, blue) wavelength components must be suppressed in accordance with the amount of red wavelength component. ,
There is a problem that even if a high-brightness lamp is used, light cannot be used efficiently.

The present invention has been made in view of the above-mentioned problems, and a semiconductor light emitting element which can easily obtain a single color and has excellent reproducibility for a wavelength having a small amount of a wavelength component of a lamp is provided. It is an object of the present invention to provide a bright projection display device with good reproducibility and white balance.

[0011]

In order to achieve the above object, a projection display apparatus according to the present invention comprises a white light source, an optical element for separating light from the light source into light of a plurality of colors, A semiconductor light-emitting light source that emits light having wavelength characteristics of color,
Light separated by the optical element, and a spatial modulation element that spatially modulates light emitted from the semiconductor light emitting source,
It has a configuration having a projection lens for projecting light spatially modulated by the spatial modulation element onto a screen. With such a configuration, a wavelength in which the amount of the wavelength component from the lamp is small is compensated for, and a bright image with good color reproducibility and white balance can be obtained.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a diagram related to an embodiment of the first invention. The optical paths of the green and blue lights are the same as in the conventional example shown in FIG. The red light is emitted from a red light emitting diode 30 provided on the incident side of a liquid crystal panel (spatial modulation element) 22 for red (R). The red light emitting diodes 30 are two-dimensionally arranged on a substrate 31. On the front surface of the light emitting diode 30, a lens array 32 for making the light from the light emitting diode 30 substantially parallel is placed. This lens array 3
The light beam from 2 is spatially modulated by a liquid crystal panel (spatial modulation element) 22 for red (R), and then enters the combining prism 14. Light transmitted through the liquid crystal panels 13, 17, and 22 for displaying each color is combined by the combining prism 14, and displayed on a screen (not shown) by the projection lens 15.

Thus, it is possible to increase the color purity of red and obtain a bright image with good color reproducibility and white balance without shortage of the amount of red light.

FIG. 2 is a diagram related to an embodiment of the second invention. In this embodiment, in addition to the conventional example shown in FIG. 5, a red light emitting diode 40 is two-dimensionally arranged on a substrate 41 around a reflector 2 as shown in FIG.
On the front surface of these red light emitting diodes 40, a lens 42 for making the light flux from the light emitting diodes 40 substantially parallel is disposed.
Fly-eye lenses 5 and 6 are arranged on the front surfaces of the reflector 2 and the lens 42.

The light beam of the red wavelength split by the fly-eye lenses 5 and 6 from the lamp 1 and the light beam from the light emitting diode 40 from the lamp 1 overlap and reach the liquid crystal panel 22 for red. On the other hand, the luminous fluxes of the blue wavelength and the green wavelength split by the fly-eye lenses 5 and 6 from the lamp 1 reach the liquid crystal panel 13 for blue (B) and the liquid crystal panel 17 for green (G), respectively. These liquid crystal panels 13, 17, 2
The light spatially modulated by 2 is combined by the combining prism 14 and is enlarged and projected as a full-color image on a screen by the projection lens 15.

As a result, the amount of red light can be increased, the red color purity can be improved, and a bright image with good color reproducibility and white balance can be obtained.

FIG. 3 is a diagram related to the embodiment of the third invention. In this embodiment, the dichroic mirror 20 is a dichroic mirror 20a as an optical element having a wavelength characteristic as shown in FIG. 4 as compared with the conventional example shown in FIG. Furthermore, this dichroic mirror 20
a, a red light emitting diode 50 is
Place in a dimension. On the front surface of the red light emitting diode 50, a lens 52 for making the light flux from the light emitting diode 50 substantially parallel is provided.
Put.

The dichroic mirror 20a has a reflection characteristic of reflecting light of a red wavelength which is split from the lamp 1 by the fly-eye lenses 5, 6 and reaches the dichroic mirror 20a via the dichroic mirrors 8, 9, 10. At the same time, the dichroic mirror 20a
Also has a transmission characteristic of transmitting red wavelength light from the light emitting diode 50. Due to these characteristics, the dichroic mirror 20a reflects the red light beam separated from the lamp 1 and transmits the light beam from the light emitting diode 50. As a result, the light beam separated from the lamp 1 and the light beam from the light emitting diode 50 arrive at the liquid crystal panel 22 in a superimposed manner.

As a result, the amount of red light can be increased, the color purity of red can be improved, and a bright image with good color reproducibility and white balance can be obtained.

In the third embodiment, the characteristics of the dichroic mirror are such that the light from the light emitting diode is transmitted and the light from the lamp is reflected.
A dichroic mirror having characteristics of reflecting a light beam from a light emitting diode and transmitting a light beam from a lamp may be used. In this case, the dichroic mirror is provided on the optical path of the light beam from the lamp, reflects the light beam from the light emitting diode, transmits the light beam from the lamp, and enters the combining prism. This makes it possible to obtain a bright image with good color reproducibility and white balance, similarly to the third embodiment.

In the first, second, and third embodiments, an example of a configuration including a plurality of spatial modulation elements using three liquid crystal panels for red, blue, and green has been described. The present invention is not limited to this, and may be configured by one liquid crystal panel (spatial modulation element).

[0023]

As described above in detail, according to the present invention, by using a lamp light source and a semiconductor light emitting light source, the amounts of red, blue, and green light necessary for white balance can be obtained, and Reproducibility is wide, and a bright projection display device can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram according to a first embodiment.

FIG. 2 is a schematic configuration diagram according to a second embodiment.

FIG. 3 is a schematic configuration diagram according to a third embodiment.

FIG. 4 is a diagram showing a mirror reflection characteristic and a semiconductor light intensity distribution with respect to a wavelength.

FIG. 5 is a schematic configuration diagram of a conventional example of a projection display device.

[Explanation of symbols]

Reference numeral 1 represents a lamp, 5, 6 represents a fly-eye lens, 20a represents a dichroic mirror, 30, 40, 50 represents a light-emitting diode, 32, 42, 52 represents a lens array.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 9/31 H04N 9/31 C 5G435 9/73 9/73 Z F term (Reference) 2H088 EA14 HA13 HA21 HA24 HA25 HA28 MA05 MA06 2H091 FA05Z FA14Z FA26X FA26Z FA29Z FA41Z LA16 LA20 MA07 5C058 EA12 EA26 EA51 5C060 BC05 DA04 HA18 HC20 HD02 JA18 JB06 5C066 AA03 CA08 EA14 KL01 KM10 KM13 5G03 GG02 GG03 DD03 GG02 DD17

Claims (5)

[Claims] 1. A white light source, an optical element for separating light from the light source into light of a plurality of colors, a semiconductor light emitting source for emitting light having a wavelength characteristic of a specific color, and the optical element for separation A spatial modulation element for spatially modulating the light to be emitted and the light emitted from the semiconductor light emitting source, and a projection lens for projecting the light spatially modulated by the spatial modulation element onto a screen. Type display device. 2. A white light source and a semiconductor light emitting source are arranged so that light from the white light source and light from the semiconductor light emitting source pass through different paths until entering the spatial light modulator. 2. The projection display device according to claim 1, wherein: 3. The semiconductor light emitting source is provided in the vicinity of the white light source. The light from the white light source and the white light source associated with the same spatial modulation element as the light from the semiconductor light emitting source are provided. 2. The projection display device according to claim 1, wherein the light is arranged so as to be superimposed on the light from the semiconductor light source and incident on the spatial light modulator. 3. 4. The light from the white light source and the light from the semiconductor light source pass through different paths until entering the spatial light modulator, transmit the light from the semiconductor light source, and The light from the semiconductor light emitting source and the light from the white light source, which are associated with the same spatial modulation element by the element that reflects the light from the white light source, are arranged so as to be superimposed and incident on the spatial modulation element. 2. The projection display device according to claim 1, wherein: 5. The light from the white light source and the light from the semiconductor light source pass through different paths until entering the spatial light modulator, reflect the light from the semiconductor light source, and The light from the semiconductor light emitting source and the light from the white light source, which are associated with the same spatial modulation element by an element that transmits light from the white light source, are arranged so as to be superimposed and incident on the spatial modulation element. The projection display device according to claim 1, wherein: