WO2006088275A1

WO2006088275A1 - Polarized stereoscopic display device without loss

Info

Publication number: WO2006088275A1
Application number: PCT/KR2005/002283
Authority: WO
Inventors: Eun-Soo Kim; Seung-Cheol Kim
Original assignee: Kwangwoon University Research Institute For Industry Cooperation
Priority date: 2005-02-15
Filing date: 2005-07-15
Publication date: 2006-08-24
Also published as: KR20060091543A

Abstract

The present invention is related to a stereoscopic display device, more specifically to a high-brightness polarized projection display device without loss of output luminosity using the polarization properties of reflective LCD projectors. According to the present invention, a polarized stereoscopic display device without loss for stereoscopically displaying a first image and a second image using a lamp light irradiated from a lamp, both images photographing an object at different angles, has a first projector outputting a first output beam corresponding to the first image and a second projector outputting a second output beam corresponding to the second image and having a polarization direction crossing the first output beam at right angles. Here, the first output beam and the second output beam are polarized in different directions from each other such that a stereoscopic image is generated without passing through a polarization filter.

Description

[DESCRIPTION]

[Invention Title]

POLARIZED STEREOSCOPIC DISPLAY DEVICE WITHOUT LOSS

[Technical Field]

The present invention is related to a stereoscopic display device, more

specifically to a high-brightness polarized projection display device without loss of

output luminosity using the polarization properties of reflective LCD projectors.

[Background Art]

A 3D display refers to a technology that allows the viewer to experience the

sense of three-dimensional animateness and reality by use of the depth information

added to two-dimensional images to which stereoscopic technologies are applied.

For more than last 50 years, more than 30 varieties of 3D display methods

have been introduced. Most of these methods display three-dimensional images using

the difference in visual perspectives of the left eye and the right eye. That is, these

conventional technologies are focusing on providing left and right images, captured by

a couple of cameras, and projecting simultaneously but separately on the screen.

The conventional left-and-right-image-separation methods are grouped in two

general methods: the eye-glasses method and the non-eye-glasses method. Included in the eye-glasses method are the anaglyph method, polarization glasses method and

liquid crystal shutter method. For the non-eye-glasses method, there are the lenticular

sheet method, parallax barrier method and optical plate method. Additionally, the

hologram method and volumetric 3D display method are under study for the method of

displaying complete three-dimensionality. Among these, the oldest, and the most

stable, 3D display method is the double polarization glasses method, which is widely

used for 3D movies and 3D monitors. Recently, large polarization stereoscopic

projection display systems using two LCD projectors are being developed.

However, it is essential for the conventional polarization stereoscopic

projection display system to have linear or circular polarization filters inserted on the

front of the projector in order to polarize the output beams from the left and right

projectors.

Below, the structure of a polarization stereoscopic projection display system,

based on a preferred embodiment of the conventional technology, will be described

with reference to Fig. 1.

An object 111 is photographed by a stereo camera 112 with a difference in

angle that is identical to the difference in perspectives of the left and right human eyes.

A 3D projector 113 is driven by the two video signals of the stereo camera 112, and

video signals for the left eye and the right eye, respectively, are generated and

projected to a projection screen 115 through polarization filters 114. When a viewer wears polarization glasses 116, which has polarization lenses that are different on the

left side and right side, and thus sees separate images on the projection screen 115

through the left and right eyes, three-dimensional images are realized.

In a conventional 3D projector 113, the 3D projector system drives the left and

right images inputted by the stereo camera 112 to generate left and right images, which

are then projected through polarization filters 114, having the perpendicular

polarization, on the projection screen 115 as images having a phase difference of a

right angle from each other. In other words, the conventional 3D projector 113 is

equipped with a couple of components, such as two lenses and two LCDs that are

driven by video signals to display the image, to realize the left and right images, which

are perpendicularly polarized and projected on the screen through the polarization

filters 114 for the left eye and the right eye.

The linear polarization filter 114, equipped in a conventional projector

described above, is illustrated in Fig. 2. In a large stereoscopic projection system using

polarization, linear polarization filters 114, with the polarization directions of +/- 45

degrees, are inserted, or circular polarization filters, with the clockwise and

counter-clockwise polarization directions, are mounted, at the front of the left and

right projectors. When polarization glasses of the same directions are worn, and the

left and right images are separated, three-dimensional images can be realized.

As described above, it is essential for the conventional polarization stereoscopic projection display system to have linear or circular polarization filters

inserted in front of the projector in order to polarize the left and right output beams

perpendicularly, consequently losing more than 50% of the luminosity of the output

beams. Several polarization projection display structures to reduce the loss of

luminosity have been recently suggested, but they have not been very effective in

solving the fundamental problems.

[Disclosure]

[Technical Problem]

Therefore, in order to solve aforementioned problems, the present invention

aims to provide a polarized stereoscopic display device without loss for improved

efficiency of luminosity.

Another object of the present invention is to provide a polarized stereoscopic

display device without loss that can provide output beams with no loss of output

luminosity by effectively eliminating the polarization filter through the use of the

inherent polarization properties and color signal processing techniques of the

reflective LCD projector.

Other objects of the present invention will be apparent through preferred

embodiments described below. [Technical Solution]

In order to achieve the above objects, an aspect of the present invention can

provide a polarized stereoscopic display device without loss comprising projectors

outputting vertical and horizontal output beams.

According to a preferred embodiment, a polarized stereoscopic display device

without loss for stereoscopically displaying a first image and a second image, both

images photographing an object at different angles, can comprise a first projector

outputting a first output beam corresponding to the first image and a second projector

outputting a second output beam corresponding to the second image and having a

polarization direction crossing the first output beam at right angles. The first output

beam and the second output beam are polarized in different directions from each other

such that a stereoscopic image can be generated without passing through a polarization

filter.

Here, the first projector outputs a first output beam linearly polarized in the

vertical direction, and the second projector outputs a second output beam linearly

polarized in the horizontal direction.

In order to achieve aforementioned objects, another aspect of the present

invention can provide a polarized stereoscopic display device without loss.

According to a preferred embodiment, a polarized stereoscopic display device

without loss for stereoscopically displaying a first image and a second image using a lamp light irradiated from a lamp, both images photographing an object at different

angles, can comprise a PBS reflecting a vertically polarized lamp light of the lamp

light and permeating a horizontally polarized lamp light; a first panel, reflecting a lamp

light reflected by the PBS by changing the phase, and outputting a first output beam

corresponding to the first image; and a second panel, reflecting a lamp light permeated

by the PBS by changing the phase, and outputting a second output beam corresponding

to the second image. The first output beam and the second output beam are polarized in

different directions from each other such that a stereoscopic image can be generated

without passing through a polarization filter.

Here, the first panel and the second panel can be one of a red reflective LCD, a

green reflective LCD and a blue reflective LCD, and the first panel and the second

panel can be arranged to be perpendicular to each other.

Moreover, the PBS can reflect a vertically polarized lamp light of the lamp

light in the direction perpendicular to incidence, and the first image can be for the right

eye, and the second image can be for the left eye.

Moreover, a polarized stereoscopic display device without loss based on the

present invention can further comprise a camera unit for photographing an object at

different angles and providing a first image and a second image, corresponding to the

left eye and the right eye.

Here, the first output beam and the second output beam can have a phase difference of 90 degrees from each other.

[Description of Drawings]

Fig. 1 shows the overall structure of a stereoscopic display device based on

conventional art;

Fig. 2 shows an illustration of a linear polarization filter based on

conventional art;

Fig. 3 illustrates the polarization properties of projector output beams;

Figs. 4-7 illustrate properties of projector output signals and linear

polarization filters;

Fig. 8 shows the overall structure of a stereoscopic display device based on a

first preferred embodiment of the present invention;

Fig. 9 shows the overall structure of a stereoscopic display device based on a

second preferred embodiment of the present invention;

Figs. 10-11 show the operating method and polarization property of a

reflective LCD based on conventional art;

Fig. 12 shows the operating method and polarization property of a reflective

LCD based on a second preferred embodiment of the present invention;

Figs. 13-15 illustrate the optical system of the inside of the reflective LCD

projector based on conventional art; and Figs. 16-18 illustrate the optical system of the inside of the reflective LCD

projector based on a second preferred embodiment of the present invention.

[Best Mode]

Below, a preferred embodiment of the polarized stereoscopic display device

without loss based on the present invention will be described with reference to the

accompanying drawings. When making reference to the accompanying drawings for

the description, identical or corresponding components will be given the same

reference numerals, regardless of the figure number, and any redundant description

will not be provided.

Polarization Property of Projector

The present invention can provide a new type of polarized stereoscopic

projection display device with no loss of output luminosity by completely eliminating

the polarization filter, which causes the loss of luminosity, from the conventional

projection display system through an effective processing of the inherent polarization

property and color video signal of an LCD projector. Fig. 3 illustrates the polarization

properties of projector output beams, and Figs. 4-7 illustrate properties of projector

output signals and linear polarization filters.

Fig. 3 is an illustration of the polarization properties of projector output beams based on conventional art.

Commercial projectors used in the polarized stereoscopic projection display

system are generally grouped in four types, based on the state of polarization of the

output beam.

Referring to Fig. 3, in the output beam 210 of most 3-panel LCD projectors,

firstly, the output of two colors is linearly polarized in one direction, and the output of

the other color is linearly polarized in a perpendicular direction. For instance, in the

output beam 210, the red and blue colors have the vertical polarization while the green

color has the horizontal polarization. This type of output beam is referred to as a first

type. Secondly, the output beam 220 in which all colors are linearly polarized in the

vertical direction is used for some 3-panel LCD projectors and most of the

single-panel LCD projectors. This type of output beam is referred to as a second type.

Thirdly, the output beam 230 in which all colors are linearly polarized in the horizontal

direction is used for some 3-panel LCD projectors and most single-panel LCD

projectors. This type of output beam is called a third type. Fourthly, the output beam

240 that is not polarized is used for CRT, DMD (digital micromirror device) and DLP

(digital light processing) projector. This type of output beam is called a fourth type.

The types of output beams described above are outlined in Table 1 below.

[Table 1 ]

In general, it is essential for a polarized stereoscopic projection display system

to have a polarization process in order to polarize the output beams perpendicularly

from the left and right projectors. Consequently, the polarization process causes the

loss of about 50% in luminosity.

Therefore, it is necessary to carefully consider the polarization state of the

beam outputted from the projector and the direction of the polarization filters in order

to realize the optimal polarized projection display system. For a CRT or DMP

projector, the direction of polarization filter is not very important because the output

beam 210 is not polarized. However, the linear polarized output beams, represented by

210, 220 and 230, of the first and third types are already polarized, the directions of the

polarized output beams and polarizer must be carefully considered in order to realize a

system for efficient stereo projection. Below, the output beam of conventional art and the output beam of the present

invention will be compared.

Figs. 4-7 depict the forms of output beam.

In the first type linearly polarized output beams, two color components (red

and blue) of the output beams 311, 312 corresponding to the right eye and left eye are

linearly polarized in the vertical direction, and the remaining one color component

(green) is linearly polarized in a perpendicular direction (horizontal) to that of the

other two color components, as shown in Fig. 4. In this case, the polarized stereoscopic

projection display system can be constructed by placing linearly polarized filters 313,

314 corresponding to the right eye and left eye at angles of +/- 45 degrees, respectively.

After the linearly polarized output beams 311, 312 of the first type pass through the

polarization filters 313, 314, the intensity of the output beams 315, 316 corresponding

to the right eye and left eye becomes reduced (indicated by the dotted lines).

In the second type linearly polarized output beams, the output beams 321 , 322

corresponding to the right eye and left eye are linearly polarized in the vertical

direction, as shown in Fig. 5. The polarized stereoscopic projection display system can

be constructed by rotating the polarization direction by +/- 45 degrees corresponding

to the right eye and left eye using a polarization rotator and placing linearly polarized

filters 323, 324 in the same direction. After the linearly polarized output beams 321 , 322 of the second type pass through the polarization filters 323, 324, the intensity of

the output beams 325, 326 corresponding to the right eye and left eye also becomes

reduced (indicated by the dotted lines).

In the third type linearly polarized output beams, the output beams 331, 332

corresponding to the right eye and left eye are linearly polarized in the horizontal

direction, as shown in Fig. 6. The polarized stereoscopic projection display system can

filters 333, 334 in the same direction. After the linearly polarized output beams 331,

332 of the third type pass through the polarization filters 333, 334, the intensity of the

output beams 335, 336 corresponding to the right eye and left eye also becomes

reduced (indicated by the dotted lines).

In the fourth type unpolarized output beams, the output beams 341, 342

corresponding to the right eye and left eye are not polarized. As shown in Fig. 7, the

stereoscopic projection display system can be constructed by placing the linear

polarization filters 343, 344, corresponding to the right eye and left eye, in front of the

projector at angles of +/- 45 degrees. After the unpolarized output beams 341 , 342 pass

through the polarization filters 343, 344, the intensity of the output beams 345, 346

corresponding to the right eye and left eye becomes reduced (indicated by the dotted

lines). While these polarization methods have a problem of losing the intensity of the

output beam entering the screen due to the presence of polarization filters, the present

invention eliminates the polarization filter and uses the polarization property of LCD

for a projector, allowing the output beams to cross at right angles.

First Embodiment

Fig. 8 is a diagram showing the overall structure of a stereoscopic display

device based on a first preferred embodiment of the present invention.

Referring to Fig. 8, an object (not illustrated) is photographed using a stereo

camera at an angular difference of the left and right eyes, and the generated video

signals are sent to two different projectors 402, 403 from an image processing unit 401.

A first projector 402 generates first output beams linearly polarized in the vertical

direction for all colors corresponding to the video signal for the left or right eye, and

projects them using a first projector lens 404. A second projector 403 generates second

output beams linearly polarized in the horizontal direction for all colors corresponding

to the video signal for the other eye, and projects them using a second project lens 405.

Later, the viewer realizes stereoscopic images by viewing the image projected on the

projection screen 406 separately on the left eye and right eye, using polarized glasses

407, which have polarized lenses that are different on the left eye and right eye. By

using a projector outputting vertically linearly-polarized output beams and a projector outputting horizontally linearly-polarized output beams, it is no longer necessary to

physically rotate the projector by 90 degrees for adjustment of the image and exchange

of the colors. Here, a camera unit (not illustrated) can be further included for providing

a first image and a second image corresponding to the left eye and right eye,

respectively, by photographing the object at different angles.

Second Embodiment

Fig. 9 depicts the polarization property of output beams based on a second

preferred embodiment of the present invention. Illustrated in Fig. 9 is a polarized

stereoscopic display method without loss based on the present invention. An object

411 is photographed using a stereo camera 412 with the angular difference of the left

eye and right eye, and the two video signals of the stereo camera 412 drive

stereoscopic projectors 413 to generate video signals for the left eye and right eye and

project on a projection screen 415 through a projector lens 414. The viewer then

realizes the stereoscopic image by viewing the image projected on the projection

screen 415 separately on the left eye and right eye, using polarized glasses 416, which

have polarized lenses that are different on the left eye and right eye. In other words,

according to a preferred embodiment of the present invention, by modifying the

optical system inside the projector in order to improve the optical efficiency, the

images of the left eye and right eye can be projected on the polarized output beam to realize the stereoscopic image.

[Mode for Invention]

Hereinafter, the operating methods and polarization properties of reflective

LCDs based on conventional art and a preferred embodiment of the present invention

will be compared.

Figs. 10-11 are diagrams showing the operating method and polarization

property of a reflective LCD based on conventional art. In Fig. 10, the reflective LCD

is arranged to be perpendicular to the incident light. In Fig. 11 , the reflective LCD is

arranged to be parallel to the incident light.

Once an unpolarized incident light enters a polarized beam splitter (PBS) 510,

the path of the incident light changes depending on the direction of polarization.

Referring to Fig. 10, the PBS 510 reflects the incident light polarized perpendicular to

the ground to the left and allows the incident light polarized parallel to the ground to

pass. Here, the incident light polarized parallel to the ground becomes reflected on a

first reflective LCD (LCOS: Liquid Crystal on Silicon, "first reflective LCD,"

hereinafter) 520 after passing through the PBS 510. The incident light changes the

polarization direction as it is reflected on the first reflective LCD 520, and becomes

polarized in the vertical direction from the ground. The first reflective LCD 520 has

the light enter and reflects in a changed polarization direction. The incident light then enters the PBS 510 again and becomes reflected to the right. Thus, the output beam

proceeds to the right, and the polarization direction is perpendicular to the ground.

Referring to Fig. 11, as described above, the PBS 510 reflects the incident

light polarized perpendicular to the ground to the left, and allows the incident light

polarized parallel to the ground to pass. Here, the incident light polarized

perpendicular to the ground is reflected on a second reflective LCD 530 after being

reflected on the PBS 510. As the incident light reflects on the second reflective LCD

530, the polarization direction changes, and the light is polarized in the parallel

direction to the ground. The incident light then enters the PBS 510 again and passes

through the PBS 510. Thus, the output beam proceeds to the right, and the polarization

direction is parallel to the ground.

Here, it is apparent to a person of ordinary skill in the art to which the

invention pertains that the PBS 510 can control the direction and angle of reflecting the

incident light according to the output direction based on the property of the projector.

Fig. 12 is a diagram showing the operating method and polarization property

of a reflective LCD based on a preferred embodiment of the present invention.

Referring to Fig. 12, the structure comprises a PBS 510, first reflective LCD 520 and

second reflective LCD 530, all of which are described in Figs. 10 and 11.

The PBS 510 reflects the incident light polarized perpendicular to the ground

to the left, and allows the incident light polarized parallel to the ground to pass. The incident light polarized parallel to the ground is reflected on the first reflective LCD

520 after passing through the PBS 510. The incident light reflected on the reflective

LCD 520 changes its polarization direction, as it is reflected on the first reflective LCD

520, and is polarized in a direction perpendicular to the ground. The incident light is

then entered into the PBS 510 and is reflected to the right. The first output beam

proceeds to the right, and its polarization direction is perpendicular to the ground.

Moreover, the incident light polarized perpendicular to the ground is reflected

on the second reflective LCD 530 after being reflected on the PBS 510. As the incident

light reflects on the second reflective LCD 530, the polarization direction changes, and

the light is polarized in the parallel direction to the ground. The incident light then

enters the PBS 510 again and passes through the PBS 510. Here, the second output

beam proceeds to the right, and its polarization direction is parallel to the ground. Thus,

the directions for the first output beam and the second output beam differ from each

other by 90 degrees, and the proceeding directions become the same.

The stereoscopic display method based on a preferred embodiment of the

present invention uses the polarization properties described above. That is, the first

output beam and the second output beam are outputted by outputting the image

corresponding to the left eye using the first reflective LCD 520 and the image

corresponding to the right eye using the second reflective LCD, respectively. And the

user wears the polarization glasses to obtain the sense of three-dimensionality for the desired image. Here, the polarization glasses have a polarization direction parallel to

the ground on the left eye and a polarization direction perpendicular to the ground on

the right eye. Although the first reflective LCD 520, the left eye and the polarized light,

which is parallel to the ground, are described to be corresponding to one another, it

should be apparent that other embodiments are also possible.

Described so far are the general operating method and polarization property of

a polarized stereoscopic display device without less. Hereinafter, a specific

embodiment of a polarized stereoscopic display device without loss based on the

present invention will be described.

Figs 13-15 are diagrams illustrating the optical system of the inside of

reflective LCD projectors based on conventional art. Fig. 13 is a 3-panel projector

whose output beams are all vertically linear-polarized; Fig. 14 a 3-panel projector

whose output beams are all horizontally linear-polarized; and Fig. 15 a single-panel

projector whose output beams are all horizontally linear-polarized.

Referring to Fig. 13, the lamp light irradiated from a lamp 610 passes through

a lens arrangement unit 613. Here, the lens arrangement unit 613 can comprise a heat

absorbing mirror, which eliminates the heat from the lamp light, an ultraviolet ray

blocking mirror, which blocks the ultraviolet ray of the lamp light, and an integrator lens, which controls the lamp light to evenly irradiate. The lamp light, which passed

through the lens arrangement unit 613, is separated to the red (R), green (G) and blue

(B) incident lights, as it passes through mirrors and dichroic mirrors 615, 617 that are

arranged on the path. Fig. 13 shows a first dichroic mirror 615 and a second dichroic

mirror 617. The first dichroic mirror 615 reflects the blue light and allows the red and

green lights to pass. The second dichroic mirror 617 reflects the green light and allows

the red light to pass. Thus, the red, green and blue lights enter the first, second and

third PBS, respectively, represented by 630a, 630b and 630c, respectively, and are

reflected after changing their polarization directions on the R, G, B reflective LCD

panels 620a, 620b, 620c. Then, these lights are outputted from an X-prism 640 through

the projection lens 650.

Polarized output beams are outputted in Figs. 14 and 15 by methods similar to

the above description, and hence only the differences will be described hereinafter.

Referring to Fig. 14, the lamp light irradiated from a lamp 610 is reflected by a PBS

645, located in front of the projection lens 650, and is separated into red, green and

blue lights, which then enter the R, G and B reflective LCD panels 670a, 670b, 670c,

respectively. Then, the output beam according to the color signal corresponding to the

photographed image is outputted through the projection lens 650.

Referring to Fig. 15, the lamp light irradiated from a lamp 610 passes through

a color wheel 616 and a light tunnel 619, in order to reproduce the color, and is reflected on a reflective LCD 690 after passing through a PBS 645. The reflected lamp

light is outputted through the projection lens 650 as an output beam corresponding to

the video signal.

Figs. 16-18 are diagrams illustrating the optical system of the inside of the

reflective LCD projector based on a preferred embodiment of the present invention.

Referring to Fig. 16, the overall path of the lamp light and the arrangement of

the components are similar to what is described in Fig. 13, and hence the differences

will be described only. The first, second and third PBSs 630(a), 630(b), 630(c) are

equipped with R, G and B reflective LCD panels 620(a), 620(b), 620(c) based on

conventional art and R, G and B reflective LCD panels 620(d), 620(e), 620(f) based on

the present invention. Therefore, each of the R reflective LCD panels 620(a), 620(f)

reflects and outputs the red light in different polarization direction from each other,

each outputting the image for the left eye and the image for the right eye, respectively.

Similarly, each of the G reflective LCD panels 620(b), 620(e) and the B reflective

LCD panels 620(c), 620(d) also outputs the image for the left eye and the image for the

right eye, respectively. As a result, the projection lens 650 outputs the output beam

polarized in two directions, and can realize a stereoscopic image when viewed by use

of polarization glasses.

The embodiment in Fig. 17 additionally comprises color prisms 680(d), 680(e), 680(f) and R, G and B reflective LCD panels 670(d), 670(e), 670(f), with

which the polarization directions of the lamp light can be controlled and stereoscopic

images can be realized. That is, stereoscopic images can be realized if the output beam

is controlled to correspond to the image for the right eye or left eye by having the

existing color prisms 680(a), 680(b), 680(c) and the R, G and B reflective LCD panels

670(a), 670(b), 670(c) output the vertically-polarized output beams and having the

additional color prisms 680(d), 680(e), 680(f) and the R, G and B reflective LCD

panels 670(d), 670(e), 670(f) output the horizontally-polarized output beams.

Referring to Fig. 18, the embodiment additionally comprises a reflective LCD

695, and stereoscopic images are realized by outputting the output beams, whose

polarizations are different, in the same method as described above.

The present invention is not restricted to what is described in the above

embodiments, and it should be apparent for those of ordinary skill in the art that a very

large number of permutations are possible within the scope and spirit of the present

invention.

[Industrial Applicability]

As described above, the polarized stereoscopic display device without loss of

the present invention can improve the optical efficiency. Moreover, the polarized stereoscopic display device without loss based on the

present invention can effectively eliminate the polarization filter by use of the

polarization properties that are inherent in reflective LCD projectors and the color

signal processing method, thereby providing output beams with no loss of luminosity.

Furthermore, the present invention can provide a new type of polarized

stereoscopic projection display system with no loss of luminosity by completely

removing the polarization filter, which causes the loss of luminosity in conventional

projection display systems, through the use of the polarization properties that are

inherent in LCD projectors and the effective processing of color video signals.

Consequently, the present invention can also provide a new approach to solving the

issue of optical loss fundamentally.

Claims

[CLAIMS]

What is claimed is:

[Claim 1 ]

A polarized stereoscopic display device without loss for stereoscopically

displaying a first image and a second image, both images photographing an object at

different angles, the device comprising:

a first projector outputting a first output beam corresponding to said first

image; and

a second projector outputting a second output beam corresponding to said

second image and having a polarization direction crossing said first output beam at

right angles,

wherein said first output beam and said second output beam are polarized in

different directions from each other such that a stereoscopic image is generated

without passing through a polarization filter.

[Claim 2]

The device of claim 1, wherein said first projector outputs a first output beam

linearly polarized in the vertical direction, and said second projector outputs a second

output beam linearly polarized in the horizontal direction.

[Claim 3]

A polarized stereoscopic display device without loss for stereoscopically

displaying a first image and a second image using a lamp light irradiated from a lamp,

both images photographing an object at different angles, the device comprising:

a PBS reflecting a vertically polarized lamp light of said lamp light and

permeating a horizontally polarized lamp light;

a first panel, reflecting a lamp light reflected by said PBS by changing the

phase, and outputting a first output beam corresponding to said first image; and

a second panel, reflecting a lamp light permeated by said PBS by changing the

phase, and outputting a second output beam corresponding to said second image,

wherein said first output beam and said second output beam are polarized in

without passing through a polarization filter.

[Claim 4]

The device of claim 3, wherein said first output beam and said second output

beam have polarization directions crossing each other at right angles.

[Claim 5]

The device of claim 3, wherein said first panel and said second panel are one of a red reflective LCD, a green reflective LCD and a blue reflective LCD.

[Claim 6]

The device of claim 3, wherein said first panel and said second panel are

arranged to be perpendicular to each other.

[Claim 7]

The device of claim 3, wherein said PBS reflects a vertically polarized lamp

light of said lamp light in the direction perpendicular to incidence.

[Claim 8]

The device of claim 1 or claim 3, wherein said first image is for the right eye,

and said second image is for the left eye.

[Claim 9]

The device of claim 1 or claim 3, further comprising a camera unit for

photographing an object at different angles and providing a first image and a second

image, corresponding to the left eye and the right eye.