JP2002341439A - Liquid crystal projector device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To brighten a projected image by using two reflection type LCDs to constitute a liquid crystal projector device. SOLUTION: Light beams from a light source are unified to s polarized light by a PBS3, red, green + blue, green, blue + red, blue, and red + green light components are respectively successively switched to p polarized light, s polarized light, p polarized light, s polarized light, p polarized light, and s polarized light by a color switch and s polarized light beam is transmitted through a PBS6, made incident on a reflection type LCD7, and modulated by red, green and blue video signals switched synchronously with the switching of the color switch 5. Video light beams Rs, Gs, Bs converted into s polarized light by reflection is reflected by the PBS6 and made incident on a projection lens 9. P polarized light beams from the color switch 5 are reflected, made incident on a reflection type LCD8, modulated by cyan, magenta and yellow video signals switched synchronously with the switching of the color switch 5 and video light beams Cp, Mp, Yp converted into p polarized light by reflection are transmitted through the PBS6, made incident on the projection lens 9 and projected to a screen together with the video light beam from the LCD7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reflective LCD (Liquid Crystal Display).
The present invention relates to a liquid crystal projector device using (d Crystal Device), which is capable of improving the brightness of a projected image and reducing the size of a housing.

[0002]

2. Description of the Related Art In a liquid crystal projector using a reflection type LCD, for example, as shown in FIG.
(Polarizing beam splitter) 11 aligns the beam with p-polarized light, enters the color wheel 31 through the condenser lens 4, rotates the color wheel 31 to decompose white light into red, green, and blue light, and transmits through the second PBS 6. Incident on the reflective LCD 7, and sequentially drives the reflective LCD 7 with red, green, and blue video signals in synchronization with the color separation of the color wheel 31,
The incident red, green and blue light rays are sequentially modulated by red, green and blue image signals, respectively reflected and converted into s-polarized image light rays, reflected by the second PBS 6 and enlarged and projected on the screen by the projection lens 9. There is. This method has the advantage that only one reflective LCD is required and that the reflective LCDs do not need to be aligned as in the case of using three reflective LCDs, but the color wheel 31 takes up space. In addition to the problem that the housing becomes large, the output image is red,
Since each of the green and blue colors is output only for about 1/3 of the time, there is a problem that the projected image is dark.

[0003]

SUMMARY OF THE INVENTION The present invention uses a color switch for color separation, uses two reflective LCDs, and modulates one color with one reflective LCD while using another reflective LCD.
It is another object of the present invention to modulate the other two colors, increase the utilization rate of light rays to brighten a projected image, and to reduce the size of a housing.

[0004]

In order to achieve the above object, a liquid crystal projector according to the present invention comprises a light source for outputting a white light beam, a first PBS for aligning the light beam from the light source with an s-polarized light beam, and White light from the first PBS,
The first primary color beam of the three primary colors is converted to p-polarized light, the second and third color beams are converted to s-polarized light, and the second color beam is then converted to p-polarized light.
In order to convert the light of the third and first colors into s-polarized light, then convert the light of the third color into p-polarized light, and turn the light of the first and second colors into s-polarized light. A first color switch for switching and outputting, and a second PB for transmitting p-polarized light and reflecting s-polarized light from the first color switch
S, the first color of the p-polarized light transmitted through the second PBS, the second color
And the third color light beams are sequentially incident, and sequentially modulated by the video signals of the first color, the second color, and the third color switched in synchronization with the switching of the first color switch. , Reflected and converted into an s-polarized light, and the second PBS
A first reflective LCD that is incident from the output side to the
Light beams of the second and third colors of the s-polarized light reflected by the BS, then the third and first colors, and then the light beams of the first and second colors are sequentially incident and synchronized with the switching of the first color switch. And then sequentially modulated with video signals of the second and third colors, then the third and first colors, then the first and second colors, reflected and converted to p-polarized light, and sequentially 2nd PB
A second reflective LCD that enters the S from the output side;
And a projection lens for projecting light rays from the first and second reflective LCDs transmitted through the PBS or reflected by the second PBS onto a screen.

[0005] Alternatively, a third PBS that outputs a light beam from the light source aligned with a p-polarized light beam, and converts a white light beam from the third PBS into a light beam of the first primary color into s-polarized light;
The light rays of the second and third colors are p-polarized, then the light rays of the second color are converted to s-polarized light, the light rays of the third and first colors are p-polarized light, and then the light rays of the third color Into s-polarized light,
A second color switch that sequentially switches and outputs the light beams of the first and second colors to be p-polarized light, a second PBS that transmits the p-polarized light beam from the second color switch and reflects the s-polarized light, The first of the s-polarized light reflected by the second PBS
, The second color, and the third color light rays are sequentially incident,
The video signals of the first color, the second color, and the third color, which are switched in synchronization with the switching of the second color switch, are sequentially modulated, reflected and converted into p-polarized light, and sequentially the second color switch.
A first reflective LCD incident on the PBS from the output side, and second and third colors of p-polarized light transmitted through the second PBS, then third and first colors, and then first and second colors Light rays are sequentially incident on the video signals of the second and third colors, then the third and first colors, and then the first and second colors, which are switched in synchronization with the switching of the second color switch. Modulated, reflected and converted to s-polarized light,
It comprises a second reflection type LCD which is incident on the PBS from the output side, and a projection lens which projects light rays from the first and second reflection type LCDs transmitted through the second PBS or reflected by the second PBS onto a screen. .

The first color is red and the second color is red.
Is green, the third color is blue, the color composed of the second and third colors is cyan, the color composed of the third and first colors is magenta, First
And the color consisting of the second color is yellow.

[0007] The white light from the third PBS is
The first primary color light beam, the second primary color light beam, and the third primary color light beam
A third color switch that sequentially switches to and outputs the light of the color, a second PBS that transmits the p-polarized light from the third color switch, a first color of the p-polarized light transmitted through the second PBS, and a second color. Light rays of a color and a third color are sequentially incident, and sequentially modulated with video signals of a first color, a second color, and a third color that are switched in synchronization with the switching of the third color switch; The reflected light is converted into a p-polarized light, and the second P
A first reflective LCD that enters the BS from the output side, and a projection lens that projects light rays from the first reflective LCD reflected by the second PBS onto the screen may be used.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments with reference to the drawings. FIG. 1 is a configuration diagram of a main portion of an embodiment of a liquid crystal projector device according to the present invention. In FIG. 1, reference numeral 1 denotes a light source that outputs white light, 2 denotes an integrator lens,
Is a first PBS that outputs a light beam from the integrator lens 2 in s-polarized light, 4 is a condenser lens, and 5 is a light beam of the first three primary colors (red) from the condenser lens 4 that is converted into p-polarized light. The light rays of the second and third colors (green and blue, ie, cyan) are converted to s-polarized light, and then the light rays of the second color (green) are converted to p-polarized light, and the third and first colors (blue and blue) are converted. The light of red, or magenta, is converted to s-polarized light, then the light of the third color (blue) is converted to p-polarized light, and the light of the first and second colors (red and green, or yellow) is converted to s-polarized light. A first color switch 6 that sequentially switches and outputs the second color switch 6 transmits a p-polarized light beam from the first color switch 5 and reflects a s-polarized light beam.
The first, second, and third light beams of the p-polarized light that have passed through the BS 6 are sequentially incident, and the first color and the second color that are switched in synchronization with the switching of the first color switch 5. The first and second color video signals are sequentially modulated, reflected, converted into s-polarized light, and incident on the second PBS 6 from the output side.
The reflective LCD 8 sequentially receives the second and third colors of the s-polarized light reflected by the second PBS 6, then the third and first colors, and then the first and second colors of light. The second and third colors, which are switched in synchronization with the switching of one color switch 5, then the third and first colors, and then the first and second color video signals are sequentially modulated, reflected and reflected. The second reflective LCD 9 that converts the light into polarized light and enters the second PBS 6 from the output side transmits through the second PBS 6 or transmits the second PBS 6.
6 is a projection lens for projecting light rays from the first and second reflection type LCDs 7 and 8 reflected by 6 onto a screen.

FIG. 2 is a block diagram of a main part of another embodiment. Reference numeral 11 denotes a third PBS for aligning the light beam from the integrator lens 2 with p-polarized light, and reference numeral 12 denotes a first primary color of the three primary colors from the condenser lens 4. Converts the color (red) light to s-polarized light, the second and third color (green and blue, or cyan) light to p-polarized light, and then converts the second color (green) light to s-polarized light. Transforming the third and first color (blue and red, or magenta) light rays into p-polarized light, and then converting the third color (blue) light ray into s-polarized light, and converting the first and second color ( Red and green,
That is, this is a second color switch for sequentially switching and outputting the yellow light beam to be p-polarized light. First reflective LCD
7 is the second and third p-polarized light transmitted through the second PBS 6.
Color, then the third and first colors, then the first and second colors
Are sequentially incident, and the images of the second and third colors, then the third and first colors, and then the first and second colors are switched in synchronization with the switching of the second color switch 12. The signal is sequentially modulated, reflected and converted into s-polarized light,
The light enters the BS 6 from the output side. The second reflective LCD 8 is
The first color light, the second color light, and the third color light of the s-polarized light reflected by the second PBS 6 are sequentially incident, and the first color and the second color that are switched in synchronization with the switching of the second color switch 12 are transmitted. The light is sequentially modulated with the video signals of the second color and the third color, reflected, converted into a p-polarized light beam, and made incident on the second PBS 6 from the output side. The other reference numerals are the same as those in FIG.

FIG. 3 is a structural view of a main part of another embodiment.
The p-polarized white light from the condenser lens 4 is sequentially switched to a light of a first color (red), a light of a second color (green), and a light of a third color (blue) of the three primary colors and output. This is the third color switch. The first reflective LCD 7 has a second PB
The first color light, the second color light, and the third color light of the p-polarized light transmitted through S6 are sequentially incident, and the first color and the second color that are switched in synchronization with the switching of the third color switch 21 are transmitted. The color and the third color video signals are sequentially modulated, reflected, converted into s-polarized light, incident on the second PBS 6 from the output side, and
The image light beam reflected by the BS 6 is projected on a screen by the projection lens 9. Other reference numerals are the same as those in FIG. 1 or FIG.

Next, the operation of the liquid crystal projector according to the present invention will be described. First, in the case of FIG. 1, the white light from the light source 1 is condensed by the integrator lens 4 and the first PB
In step S 3, the light is made into an s-polarized light beam, condensed by the condenser lens 4, and incident on the first color switch 5. The first color switch 5 shifts the phase of the wavelength range of the red light, which is the first color, into a wavelength range.
Rotate 90 ° to p-polarized light (Rp), the green and blue light rays of the second and third colors, ie, the cyan light ray, are output as s-polarized light (Cs), and then the green light of the second color. The phase of the wavelength region is rotated by 90 ° to be p-polarized light (Gp), and the third and first colors of blue and red light, ie, the light of magenta, are output as s-polarized light (Ms). The phase of the wavelength region of the blue light beam, which is a color, is rotated by 90 ° to be p-polarized light (Bp), and the red and green light beams of the first and second colors, ie, the yellow light beam, are output as s-polarized light (Ys). Are sequentially switched. The Rp, Gp, and Bp rays from the first color switch 5 are sequentially transmitted to the second P switch.
The light passes through the BS 6, enters the first reflective LCD 7, is sequentially modulated by red, green, and blue video signals switched in synchronization with the switching of the first color switch 5, reflected, Rs, G
The light beams become s and Bs image light rays, sequentially return to the second PBS 6, are reflected, and enter the projection lens 9. The Cs, Ms, and Ys light beams from the first color switch 5 are sequentially reflected by the second PBS 6 and enter the second reflection type LCD 8, and are switched in synchronization with the switching of the first color switch 5, cyan, magenta, and yellow. Is sequentially modulated by the video signal of
It becomes Mp, Yp image light rays, sequentially passes through the second PBS 6,
The light enters the projection lens 9 and is projected on a screen together with the image light rays from the first reflective LCD 7.

In the case of FIG. 2, the white light beam condensed by the integrator lens 4 is aligned with the p-polarized light beam by the third PBS 11,
The light is condensed by the condenser lens 4 and is incident on the second color switch 12. The second color switch 12 rotates the phase of the wavelength region of the red light of the first color by 90 ° to s-polarized light (R
s) The green and blue light rays of the second and third colors, ie, the cyan light rays, are output as p-polarized light (Cp), and then the phase of the wavelength range of the green light of the second color is rotated by 90 °. The s-polarized light (Gs) is output, and the blue and red light rays of the third and first colors, that is, the magenta light rays, are output as p-polarized light (Mp). The phase is rotated by 90 ° to be s-polarized light (Bs), and the first and second colors, red and green light rays, that is, yellow light rays are sequentially switched so as to output (Yp) with p-polarized light. The Rs, Gs, and Bs rays from the second color switch 12 are sequentially reflected by the second PBS 6, and
The light enters the reflection type LCD 8 and is sequentially modulated with red, green and blue video signals switched in synchronization with the switching of the second color switch 12, reflected, and becomes Rp, Gp, and Bp video light rays. The light passes through and enters the projection lens 9. The Cp, Mp, and Yp rays from the second color switch 12 sequentially pass through the second PBS 6 and enter the first reflection type LCD 7, and are switched in cyan, magenta, and yellow in synchronization with the switching of the second color switch 12. Are sequentially modulated and reflected by the video signal, and are converted into Cs, Ms, and Ys video light rays, sequentially returned to the second PBS 6, reflected, and incident on the projection lens 9,
The light is projected on the screen together with the image light rays from the second reflective LCD 8.

In the case of FIG.
The polarized white light enters the third color switch 21 and
Red light (Rp), the second color, green light (G
p) and then switch to sequentially output the blue light (Bp) as the third color. P of each color from the third color switch 21
The polarized light sequentially passes through the second PBS 6 and the first reflective LC
D7, which is sequentially modulated with red, green, and blue video signals switched in synchronization with the switching of the third color switch 21 and reflected, becomes Rp, Gp, and Bp video light beams, and sequentially becomes the second light beam.
The light returns to the PBS 6, is reflected, enters the projection lens 9, and is sequentially projected on a screen. In the case of this configuration, the utilization rate of light rays is basically the same as in the prior art, but the size of the housing can be reduced because no color wheel is used.

[0014]

As described above, according to the liquid crystal projector of the present invention, the white light from the light source is
By the color switch, p (s) polarized red and s
(P) Cyan, p (s) green and s (p) magenta, p (s) blue and s (p) yellow light are output. Reflective LCD
In addition, the s-polarized light is sequentially incident on another reflection type LCD, and the modulated and reflected image light is projected on the screen (or the p-polarized light and the s-polarized light are inverted and combined). The light is not wasted as in the case of using the conventional color wheel, so that the brightness of the projected image is improved, and the housing can be downsized because the color wheel is not used. If the color switch is configured to sequentially output red (red), green (green), and blue (blue) polarized light from the color switch, and to enter and modulate a single reflective LCD, the brightness of the projected image is basically the same. Although not different from the conventional case, the size of the housing can be reduced because the color wheel is not used.

[Brief description of the drawings]

FIG. 1 is a main part configuration diagram of an embodiment of a liquid crystal projector device according to the present invention.

FIG. 2 is a main part configuration diagram of another embodiment of the liquid crystal projector device according to the present invention.

FIG. 3 is a main part configuration diagram of another embodiment of the liquid crystal projector device according to the present invention.

FIG. 4 is a configuration diagram of a main part of an example of a conventional liquid crystal projector device.

[Explanation of symbols]

 Reference Signs List 1 light source 2 integrator lens 3, 6, 11, 21 first, second, third, fourth PBS 4 condenser lens 5, 12, 21 first, second, third color switch 7, 8 reflective LCD 9 projection lens 31 color wheel

Claims (4)

[Claims] 1. A light source that outputs a white light beam, a first PBS (polarizing beam splitter) that outputs a light beam from the light source while aligning the light beam with an s-polarized light beam, and a white light beam from the first PBS is converted into first light of three primary colors. Convert the color light into p-polarized light, convert the second and third color light into s-polarized light, then convert the second color light into p-polarized light, and convert the third and first color light into s-polarized light. A first color switch that converts the light of the third color to p-polarized light, and then sequentially switches and outputs the light of the first and second colors to s-polarized light; and Second P that transmits p-polarized light and reflects s-polarized light
A first color light beam, a second color light beam, and a third color light beam of the p-polarized light transmitted through the second PBS and the second PBS sequentially enter the first and second light beams;
The video signals of the first color, the second color, and the third color, which are switched in synchronization with the switching of the color switch, are sequentially modulated, reflected and converted into s-polarized light, and sequentially the second PBS.
To the first reflective LCD (Liquid Crysta
l Device) and the second and third colors of the s-polarized light reflected by the second PBS, then the third and first colors, and then the light beams of the first and second colors. The second and third colors, which are switched in synchronization with the switching of one color switch, then the third and first colors, and then the first and second color video signals are sequentially modulated, reflected and p-polarized. A second light beam is converted into a light beam and sequentially incident on the second PBS from the output side.
A reflection-type LCD, and a transmission or transmission through the second PBS.
A liquid crystal projector comprising: a projection lens configured to project light rays from the first and second reflective LCDs reflected by a BS onto a screen. 2. A light source that outputs a white light beam, a third PBS that outputs a light beam from the light source aligned with a p-polarized light beam, and outputs a white light beam from the third PBS into a light beam of the first primary color, s. Convert the light of the second and third colors to p-polarized light, then convert the light of the second color to s-polarized light, convert the light of the third and first colors to p-polarized light, A second color switch that converts the light of the third color into s-polarized light, sequentially switches and outputs the light of the first and second colors to be p-polarized, and a p-polarized light from the second color switch. Penetrating s
A second PBS that reflects polarized light rays, and light rays of the first, second, and third colors of s-polarized light reflected by the second PBS are sequentially incident, and synchronized with the switching of the second color switch. The first color, the second color, and the third
A first reflection type LCD sequentially modulates with a video signal of a color, reflects and converts it into a p-polarized light, and sequentially enters the second PBS from an output side, and a second p-polarized light transmitted through the second PBS.
And third color, then third and first color, then first
And a second color light beam are sequentially incident, and the second and third light beams are switched in synchronization with the switching of the second color switch.
Color, then the third and first colors, then the first and second colors
The second reflection type LCD sequentially modulates with the video signal of the color, reflects and converts it into s-polarized light, and sequentially enters the second PBS from the output side, and transmits or transmits through the second PBS or the second PB.
A liquid crystal projector device comprising: a projection lens for projecting light rays from the first and second reflective LCDs reflected by S onto a screen. 3. The method according to claim 1, wherein the first color is red, the second color is green, the third color is blue, and the second and third colors are cyan. 3. The liquid crystal projector according to claim 1, wherein the color composed of the third and first colors is magenta, and the color composed of the first and second colors is yellow. 4. 4. A light source that outputs a white light beam, a third PBS that outputs a light beam from the light source aligned with a p-polarized light beam, and a white light beam from the third PBS is a light beam of a first primary color of three primary colors. A third color switch that sequentially switches and outputs the light of the second color and a light of the third color, a second PBS that transmits the p-polarized light from the third color switch,
The first color light, the second color light, and the third color light of the p-polarized light that have passed through the PBS are sequentially incident, and the first color and the second color that are switched in synchronization with the switching of the third color switch. color,
And a first reflection type LCD sequentially modulated by the video signal of the third color, reflected and converted into a p-polarized light, and sequentially incident on the second PBS from the output side, and the first reflective LCD reflected by the second PBS. A liquid crystal projector device comprising a projection lens for projecting a light beam from a reflective LCD onto a screen.