JPH0772450A - Projection display device - Google Patents

Abstract

PURPOSE:To provide a projection type display device capable of realizing display where brightness is prioritized or display where color reproducibility is prioritized by one device. CONSTITUTION:A light source part 1 can be attached to/detached from a projection display device main body 7 provided with 1st optical elements DM1 to DM4 performing the color separation or synthesis of light source light, liquid crystal panel unit parts P1 to P3 performing the modulation of light intensity or the modulation of light phase, and a projection optical element 3 projecting each color light to a screen. Therefore, the light source part suitable to use purpose can be easily combined. Since a 2nd optical element DF whose spectral characteristic is different in accordance with wavelength is installed in the device main body 7 or the light source part 1, the spectrum of the light source light is changed and color purity is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection type display device used for video display, large screen display and the like.

In recent years, display devices have been used for various purposes in the field of image processing and the like. Therefore, there is a demand for a display device that can obtain optimum color purity, color balance, illuminance, etc. according to the use purpose.

[0003]

2. Description of the Related Art FIG. 12 shows a structure of a conventional projection type display device, and FIG. 13 shows each dichroic mirror DM1-4.
Shows the spectral transmittance of.

In FIG. 12, the white light emitted from the light source unit 1 is blocked by the UV / IR cut filter 2 from the ultraviolet light and the infrared light, and then the dichroic mirror having the spectral transmittance shown in FIG. The DM1 transmits the light in the blue band B and reflects the light in the green to red bands. Generally, a halogen lamp, a metal halide lamp, or the like is used as the light source, and a dichroic prism or the like is used as the color separation / synthesis optical element.

The blue band light transmitted through the dichroic mirror DM1 changes its optical path by 90 degrees by the total reflection mirror M1 and enters the liquid crystal panel P1 through the condenser lens L1.
Here, the light is modulated according to the input signal. The light-modulated light is incident on the dichroic mirror DM3 having the spectral transmittance shown in FIG. Since the dichroic mirror DM3 has a characteristic of transmitting the light other than the red band light from FIG. 13C, the modulated blue band light passes through the dichroic mirror DM3 as it is, and the spectral transmittance shown in FIG. Is incident on the dichroic mirror DM4. Since the dichroic mirror DM4 has a characteristic of reflecting light other than the green band from FIG. 13D,
The blue band light is reflected by the dichroic mirror DM4 and is incident on the projection lens 3 with its optical path changed by 90 degrees.

On the other hand, the green to red band light reflected by the dichroic mirror DM1 and having its optical path changed by 90 degrees is shown in FIG.
The light enters the dichroic mirror DM2 having the spectral transmittance shown in 3 (b). As shown in FIG. 13B, since the dichroic mirror DM2 has a characteristic of reflecting the red band light R, the red band light is reflected here, and its optical path is set to 90 degrees.
After changing the degree, the light enters the liquid crystal panel P2 through the condenser lens L2, and is optically modulated here according to the input signal. The light-modulated red band light is incident on the dichroic mirror DM3. Since the dichroic mirror DM3 has a spectral transmittance that reflects the red band light, the dichroic mirror DM3 is reflected here, changes the optical path by 90 degrees, and enters the dichroic mirror DM4. Since the dichroic mirror DM4 has a characteristic of reflecting light other than the green band light, the red band light is reflected by the dichroic mirror DM4 and is incident on the projection lens 3 with its optical path changed by 90 degrees.

The green band light transmitted through the dichroic mirror DM2 is incident on the liquid crystal panel P3 via the condenser lens L3, and is optically modulated there according to the input signal. The light-modulated green band light is incident on the dichroic mirror DM4 with its optical path changed by 90 degrees by the total reflection mirror M2. Since the dichroic mirror DM4 has a characteristic of transmitting the green band light, the green band light passes through the dichroic mirror DM4 as it is and enters the projection lens 3.

The light incident on the projection lens is projected on the screen to form an image. The condensing lens provided adjacent to each liquid crystal panel is for allowing the light emitted from the liquid crystal panel to efficiently enter the projection lens.

In the conventional projection type display device having such a structure, when the contrast of each liquid crystal panel is sufficiently high, the color purity of the red band light depends on the spectral characteristics of the light source light and the spectral transmittance of the dichroic mirrors DM1 to DM4. The color purity of the green band light is determined by the spectral characteristic of the light source light and the spectral transmittance of the dichroic mirrors DM1, DM2, DM4, and the color purity of the blue band light is determined by the spectral characteristic of the light source light and the dichroic mirrors DM1, D.
It is determined by the spectral transmittance of M3 and DM4.

As described above, in the configuration of the conventional projection type display device, each optical element is designed so that optimum color balance and color purity can be obtained when a specific lamp is used.

[0011]

However, depending on the purpose of use of the projection type display device, if a bright display is required even if the device is large, a bright display is required even if the color purity is lowered. There are various requirements such as when it is done. This can be dealt with to some extent by changing the type or power of the lamp, but in the case of the conventional projection type display device, the lamp is fixed inside the device body and it is possible to meet the above requirements. There wasn't. Also, even if only the lamp is replaced, the spectral characteristics of the lamp and the spectral characteristics of each optical element do not correspond,
There was a high possibility that the color purity and the color balance would be lost and the display quality would be significantly deteriorated.

Therefore, an object of the present invention is to provide a projection type display device capable of realizing display with priority on brightness or display with priority on color reproducibility with one device.

[0013]

In order to solve the above-mentioned problems, a projection type display device according to the present invention performs a first optical element (DM1 to DM4) for performing color separation of light from a light source, a light intensity modulation or an optical phase modulation. Liquid crystal panel unit parts (P1 to 7) and projection optical elements (3, 11 to 1) that project light of each color onto a screen.
A projection type display device body having 3), and a light source section (1) detachable from the projection type display device body (7),
It is characterized by having.

Further, in the projection type display device according to the present invention, the projection type display device body (7) or the light source section (1) further includes a second optical element (DF) having different spectral characteristics depending on the wavelength. Is characterized by.

[0015]

According to the above-mentioned structure of the present invention, the first optical element (DM1 to DM4) for color-separating or synthesizing the light from the light source, and the liquid crystal panel unit portion (P1 to P1 to perform light intensity modulation or optical phase modulation)
7), and the light source unit (1) is attachable / detachable to / from the projection type display device main body having the projection optical elements (3, 11 to 13) for projecting each color light on the screen. Therefore,
It is possible to easily combine the light source units suitable for the purpose of use.

Further, according to the above configuration of the present invention, the projection type display device main body (7) or the light source section (1) is further provided with a second optical element (DF) having a spectral characteristic different depending on the wavelength. Therefore, it is possible to improve the color purity by changing the spectrum of the light from the light source.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same reference numerals are used for the same components.

FIG. 1 is a perspective view of a projection type display device according to the present invention. The projection display device according to the present invention includes a light source unit 1.
And a projection device body 7. The light source unit 1 includes a type (halogen lamp, metal halide lamp, etc.), setting conditions (illuminance ratio, frost state, etc.), power (150
W, 250 W, etc.) are prepared. Therefore, the size and type of the screen to be displayed (full-color display, large-screen display, etc.), the display giving priority to brightness or the display giving priority to color reproducibility can be selected according to the purpose.

The projection apparatus main body 7 is provided with an optical system component excluding a lamp and a lamp lighting power source, a control circuit section, and a control circuit power source. The interface section 4 between the projection apparatus main body 7 and the light source section 1 is composed of an input power source for the lamp lighting power source, a lamp lighting discrimination signal, a temperature monitor signal and the like. A ventilation hole is provided in the exterior of the light source unit, and when the light source unit 1 is incorporated in the projection device body 7, the inside of the light source can be cooled by the fan built in the projection device body 7. First Embodiment FIG. 2 shows a schematic configuration of a projection type display device according to a first embodiment of the present invention. In the first embodiment, the light source unit 1 has a dichroic filter DF having a characteristic for changing the spectral characteristic of the light source, and the dichroic filter D.
A mechanism is provided for inserting and removing F in the irradiation optical path of the lamp. By sliding this dichroic filter DF outside the irradiation light path of the lamp, the dichroic filter DF is directly projected onto the projection optical system body without manipulating the light source light spectrum, and by sliding the dichroic filter DF into the irradiation light path of the lamp, It changes the spectrum of light and changes the color purity and color balance. That is, the color purity obtained when the dichroic filter DF is not inserted in the irradiation optical path is lower than the color purity when the dichroic filter DF is inserted. Therefore, when the dichroic filter DF is inserted, high-quality display with high color purity is possible, which is suitable for small-screen video display and the like. When the dichroic filter DF is not inserted,
Although the color purity is not so high, it produces a bright display, which is suitable for large-screen display.

In this way, the dichroic filter DF
It is possible to realize two kinds of display quality by providing a mechanism for inserting / removing into / from the irradiation optical path. The dichroic filter DF can be inserted and removed manually, or can be configured by combining a power generator and a power transmitter.

FIG. 3 shows the detailed construction of the projection type display device according to the first embodiment of the present invention, FIG. 4 shows the spectral transmittance of the dichroic filter DF used in the present invention, and FIG.
3 shows the cut wavelengths (wavelengths at which the transmittance is 50%) of the dichroic filter DF and the dichroic mirrors DM1 to DM4 used in FIG. These cut wavelengths are design examples when a certain metal high-ride lamp is used. However, these numerical values are merely examples, and are not limited to these values. Various values can be set according to the type of light source.

The optical system in the projection apparatus main body 7 shown in FIG.
Since it is the same as the optical system in the conventional projection type display device shown in FIG. 12, detailed description thereof will be omitted. The spectral transmittances of the dichroic mirrors DM1 to DM4 are the same as those shown in FIG.

Here, when the dichroic filter DF is not inserted in the irradiation optical path, DM1, DM2, D
The color purity determined by the cut wavelengths of M3 and DM4 is lower than the color purity required for video display, but is set sufficient for large screen display. When the dichroic filter DF is not inserted in the irradiation light path, the band light of about 490 to 510 nm and about 5
Band light of 70 to 600 nm is also used as projection light. However, light near 500 nm and 585 nm
The light in the vicinity is light that reduces blue purity, green purity, and red purity, respectively.

Therefore, when high-quality display with high color purity such as video display is required, the dichroic filter D is used.
Insert F into the irradiation light path. Dichroic filter D
When F is inserted in the irradiation optical path, the band light of about 490 to 510 nm and the band light of about 570 to 600 nm are not emitted to the display device body 7 side, and the light of about 490 nm or less is used as the blue band display light. Light of about 510 to 570 nm is used as the green band display light, and projection light of about 600 nm or more is used as the red band display light.

FIG. 6 shows the spectral characteristics of the lamp with and without the dichroic filter DF inserted. By thus inserting the dichroic filter DF in the irradiation optical path, the color purity can be improved.
However, in general, if the light that reduces the color purity is blocked, the color purity is improved, but the amount of light is reduced. In the case of the dichroic filter DF, the cut band and the transmittance are set so that the color purity and the color balance can be secured without significantly reducing the light amount.

FIG. 7 shows an example of the substrate structure of the dichroic filter DF used in the projection type display device of the present invention, and FIG. 8 shows the spectral transmittance of the dichroic filter DF. One surface of the dichroic filter DF shown in FIG. 7 is coated with a dichroic coating layer DF1 having a spectral transmittance that reflects band light of about 490 to 510 nm shown in FIG. 8A, and the other surface is coated with the dichroic coating layer DF1. Dichroic coating layer D having a spectral transmittance for reflecting light in the band of about 570 to 600 nm shown in FIG. 8B.
Coat with F2. The filter characteristics shown in FIGS. 8A and 8B are combined to obtain the bandpass filter characteristics shown in FIG. 8C, that is, the spectral transmittance shown in FIG.
Here, the dichroic coating layers are provided on both surfaces of one substrate, but two substrates may be provided with coating layers having different spectral transmittances, respectively. Further, if one having a spectral transmittance of either FIG. 8A or FIG. 8B is used as the dichroic filter DF, it is possible to improve either blue color purity or red color purity. it can.

Although the dichroic filter DF and the mechanism capable of inserting and removing the dichroic filter DF in the optical path are provided in the light source section 1 in FIG. 3, they may be provided in the projection apparatus main body 7 as shown in FIG. . Further, as shown in FIG. 10, when the light source unit 1 is provided with the dichroic filter DF and a mechanism capable of inserting and removing the dichroic filter DF in the optical path, the dichroic filter DF is provided between the dichroic mirror DM1 and the dichroic mirror DM2. It can also be provided. However, in this case, the effect of the dichroic filter DF acts on the red band light and the blue band light. The color separation order and the insertion position of the dichroic filter DF are not limited to these.

In the above, the dichroic filter D
Although F has been described, it is not limited to this.
A dichroic mirror DM can also be used. Second Embodiment FIG. 11 shows the configuration of a projection type display device according to a second embodiment of the present invention.

In FIG. 11, the white light emitted from the light source unit 1 is blocked by the UV / IR cut filter 2 to block the ultraviolet light and the infrared light, and then is passed through the dichroic filter DF or not through the dichroic filter DF. It is incident on the mirror DM2. As in the first embodiment, a halogen lamp, a metal halide lamp or the like is used as the light source, and a dichroic prism or the like is used as the color separation / synthesis optical element in addition to the dichroic mirror.

Light in the red band R is transmitted and light in the blue to green band is reflected by the dichroic mirror DM2 having the spectral transmittance shown in FIG. 13B. The red band light reflected by the dichroic mirror DM1 changes its optical path by 90 degrees, and passes through the condenser lens L5 to the liquid crystal panel P.
It is incident on the beam 5, and is optically modulated here according to the input signal. The light-modulated light enters the projection lens 11.

On the other hand, the blue-green band light transmitted through the dichroic mirror DM2 is incident on the dichroic mirror DM1 having the spectral transmittance shown in FIG. 13 (a). FIG.
From (a), since the dichroic mirror DM1 has the property of reflecting the light other than the blue band light B, the green band light is reflected here, its optical path is changed by 90 degrees, and the condensing lens L
It is incident on the liquid crystal panel P6 via 6 and is optically modulated there according to an input signal. The light-modulated green band light enters the projection lens 12.

The blue band light transmitted through the dichroic mirror DM1 is moved along its optical path by the total reflection mirror M3.
After changing the degree, the light enters the liquid crystal panel P7 through the condenser lens L7 and is optically modulated according to an input signal. The light-modulated green band light enters the projection lens 13.

Then, the light incident on the projection lens is projected on the screen to form an image. The condensing lens provided adjacent to each liquid crystal panel is for allowing the light emitted from the liquid crystal panel to efficiently enter the projection lens.

Here, when the dichroic filter DF is not inserted in the irradiation optical path, the color purity determined by the cut wavelengths of DM1 and DM2 is lower than the color purity required for video display, but for large screen display. Is set to a sufficient color purity. When the dichroic filter DF is not inserted in the irradiation optical path, band light of about 490 to 510 nm and about 570 to 600 nm
The band light of is also used as the projection light. However,
The light near 500 nm and the light near 585 nm have blue purity,
It is light that reduces the green and red purities, respectively.

Therefore, when high quality display with high color purity such as video display is required, the dichroic filter D is used.
Insert F into the irradiation light path. Dichroic filter D
When F is inserted in the irradiation optical path, the band light of about 490 to 510 nm and the band light of about 570 to 600 nm are not emitted to the display device body 7 side, and the light of about 490 nm or less is used as the blue band display light. Light of about 510 to 570 nm is used as the green band display light, and projection light of about 600 nm or more is used as the red band display light.

The spectral transmittance of the dichroic filter DF, the structure, the location of the dichroic filter DF, the possibility of replacement with the dichroic mirror DM, etc. are the same as those in the first embodiment.
The description is omitted.

[0037]

According to the above-described structure of the present invention, since the light source section can be attached to and detached from the main body of the projection type display device, the light source section suitable for the purpose of use can be easily combined. That is, depending on the size or type of screen to be displayed (full color display, large screen display, etc.), or the type of lamp (halogen lamp, metal halide lamp, etc.), lamp setting conditions (illuminance ratio, frost state) By optimally selecting the electric power (150 W, 250 W, etc.), it is possible to realize display with priority on brightness or display with priority on color reproducibility with one device.

Further, in the main body of the projection type display device or the light source section, the second optical element (D
F) and its insertion / removal mechanism are also provided, so that it is possible to realize a display that prioritizes brightness or a display that prioritizes color reproducibility without using several types of light sources, and always create an optimal display state. You can

[Brief description of drawings]

FIG. 1 is a perspective view of a projection type display device according to the present invention.

FIG. 2 is a diagram showing a schematic configuration of a projection type display device according to a first embodiment of the present invention.

FIG. 3 is a diagram showing a detailed configuration of a projection type display device according to a first embodiment of the present invention.

FIG. 4 is a dichroic filter DF used in the present invention.
It is a figure which shows the spectral transmittance of.

FIG. 5 is an explanatory diagram of cut wavelengths of the dichroic filter DF and dichroic mirrors DM1 to DM4.

FIG. 6 is a diagram showing spectral characteristics of a lamp.

FIG. 7 is a diagram showing a substrate configuration of a dichroic filter DF used in the projection type display device of the present invention.

FIG. 8 is a diagram showing the spectral transmittance of the dichroic filter DF used in the projection display device of the present invention.

FIG. 9 is a diagram showing a schematic configuration of a projection type display device according to the present invention.

FIG. 10 is a diagram showing a schematic configuration of a projection type display device according to the present invention.

FIG. 11 is a diagram showing a detailed configuration of a projection type display device according to a second embodiment of the present invention.

FIG. 12 is a diagram showing a configuration of a conventional projection display device.

FIG. 13 is a diagram showing a spectral transmittance of a dichroic mirror.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Light source part 2 ... UV / IR cut filter 3, 11-13 ... Projection lens 4, 8 ... Interface part 5 ... Lamp lighting ballast 6 ... Lamp house 7 ... Projection device main body 9 ... Lamp 10 ... Projection type display device DF ... Dichroic filters DF1 to DF2 ... Danchroic coating layers DM1 to DM4 ... Dichroic mirrors M1 to M3 ... Total reflection mirrors P1 to P7 ... Liquid crystal panels L1 to L6 Condensing lenses G ... Glass substrates

Claims (5)

[Claims] 1. A first optical element (D) for performing color separation of light from a light source.
M1-4), a liquid crystal panel unit section (P1-7) for performing light intensity modulation or optical phase modulation, and a projection type display having projection optical elements (3, 11-13) for projecting each color light on a screen. A projection type display device comprising: a device main body; and a light source section (1) which is detachable from the projection type display device main body (7). 2. The projection display device according to claim 1, wherein the light source unit (1) has a plurality of lamps of different types or powers. 3. The projection type display device according to claim 1, wherein the projection type display device main body (7) or the light source unit (1).
Of the second optical element (D
A projection display device further comprising F). 4. The projection type display device according to claim 3, wherein the second optical element (DF) has a wavelength of approximately 490 nm to 510 nm.
spectral characteristics for blocking light in the band of nm or light in the band of approximately 570 nm to 600 nm, or approximately 490 to 510
A projection type display device having a spectral characteristic of blocking light in the band of nm and light in the band of approximately 570 to 600 nm. 5. The projection type display device according to claim 3, wherein the projection type display device main body (7) or the light source unit (1).
However, the projection type display device is provided with a mechanism for inserting and removing the second optical element (DF) in the optical path.