JPH08110495A - Stereoscopic display device - Google Patents

Abstract

PURPOSE: To provide a stereoscopic display device capable of stereoscopic viewing with maximum illuminance at an observing position without increasing a cross-talk area even though a liquid crystal panel whose numerical aperture of a picture element in a horizontal direction is >=50% is used in the stereoscopic display device. CONSTITUTION: As to this stereoscopic display device provided with a light source 1, the liquid crystal panel 2, and a parallax barrier 3 arranged in front of the panel 2, a grid-shaped barrier 4 on an incident side in which many slits are arranged between the panel 2 and the light source 1 is set.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic display device in which a parallax barrier is provided on the observer side of a display screen, and in particular, a range in which stereoscopic vision can be performed with maximum illuminance at the observation position without increasing the crosstalk area. The present invention relates to a stereoscopic display device capable of enlarging.

[0002]

2. Description of the Related Art As shown in FIG. 17, a right-eye image 21 and a left-eye image 22 are formed on a display screen 2 composed of a liquid crystal panel, and these images are separated by a parallax barrier 3 for observation. In the parallax barrier type stereoscopic display device, the pixel aperture ratio (l / L) in the horizontal direction is 50.
Many are more than%. Here, L is the pixel pitch in the horizontal direction of the display screen 2, and l is the pixel aperture width.

In this stereoscopic display device, since the light-shielding portion 31 of the parallax barrier 3 exists between the left-eye 51 and the right-eye image 21, the light ray 53 traveling from the right-eye pixel to the left-eye 51 of the parallax barrier 3. The right-eye image 21 cannot be seen from the position of the left eye 51 because the light-shielding portion 31 blocks the light. The same applies to the relationship between the right eye 52 and the left eye image 22.

Opening ratio of parallax barrier 3 (b / B)
Is designed so that the pupil can see each pixel through each opening 32 of the parallax barrier 3 over the entire opening width l at the optimum observation position 61 as shown in FIG. 18, for example. That is, the parallax barrier 3
The aperture ratio (b / B) of (1 / 2L) × 1 shown in FIG.
It is set to 00% or more. Here, B is the horizontal barrier pitch of the parallax barrier 3, and b is the opening width of the opening 32.

The illuminance at the position of the pupil when each pixel can be seen through the opening 32 of the parallax barrier 3 over the entire opening width l is called "maximum illuminance". The range in which the illuminance is obtained is the aperture ratio (b / B) of each aperture 32 of the parallax barrier 3.
In case of (1 / 2L) × 100%, it is limited to one point 62.

A region indicated by reference numeral 63 in FIG. 18 is a region in which both the right-eye image 21 and the left-eye image 22 are observed with one eye and stereoscopic vision becomes impossible, and is called a crosstalk region. It

In order to reduce the crosstalk area,
The aperture ratio (b / B) of the parallax barrier 3 may be reduced. For example, as shown in FIG. 19, the aperture ratio (b / B) of the parallax barrier 3 is {(L-1) / 2L} × 10.
When it is set to 0%, the crosstalk region disappears and the range 64 in which stereoscopic vision is possible becomes the largest, but the illuminance at the optimum observation position 61 becomes smaller than that in the case of FIG. 18, and the maximum illuminance is (L-1) / l. Becomes

Opening ratio of parallax barrier 3 (b / B)
When is smaller than {(L-1) / 2L} × 100%, not only the illuminance at the optimum observation position becomes smaller, but also an area where no image is visible appears.

On the contrary, the aperture ratio of the parallax barrier 3 (b
/ B) is larger than (l / 2L) × 100%,
As shown in FIG. 20, the range 62 in which the maximum illuminance is obtained is large, but the crosstalk region 63 is also large. In the case of FIG. 20 in which the range in which stereoscopic vision is possible and the range in which maximum illuminance is obtained match, the range in which stereoscopic vision is possible is the smallest (L-1) / L in FIG.

Therefore, in the conventional parallax barrier type stereoscopic display device, the aperture ratio (b / B) of the parallax barrier 3 is {(L-1) / 2L} × 100% or more,
It can be seen that (1 / 2L) × 100% or less is desirable.

[0011]

As described above, the aperture ratio (b / B) of the parallax barrier 3 at which the maximum illuminance is obtained at the optimum observation position 61 is (l / 2L) × 100% or more,
The two conditions that the aperture ratio (b / B) of the parallax barrier 3 in which the crosstalk area is eliminated are {(L-1) / 2L} × 100% or less are the horizontal pixel aperture ratio (l
/ L) is 50% or less, that is, only when L ≧ 2l, and these conditions are not simultaneously satisfied when using a liquid crystal panel having a pixel aperture ratio (l / L) in the horizontal direction of more than 50%. .

In particular, when the observer moves left and right from the optimum observation position 61, the sum of the illuminances of the right-eye image 21 and the left-eye image 22 at the pupil position (hereinafter referred to as total illuminance).
If there is no change in, the range in which stereoscopic vision is possible becomes very small.

Further, since the image on the liquid crystal panel is separated for the right eye and the left eye in order to observe a stereoscopic image, the illuminance at the observation position is halved compared to the case of observing a plane image using the same liquid crystal panel. There is also the problem of becoming.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a stereoscopic display device capable of enlarging the range in which stereoscopic viewing is possible at the maximum illuminance without increasing the crosstalk area. It is a thing.

[0015]

A first stereoscopic display device according to the present invention comprises a light source, a display screen, and a parallax barrier installed on the observer side of the display screen. An image on the display screen is parallax barrier. In order to achieve the above-mentioned object on the premise of a stereoscopic display device separated by the above, a lattice-shaped entrance-side barrier in which a large number of slits are arranged is installed between the display screen and the light source.

With this structure, it is possible to expand the range in which stereoscopic viewing can be performed with the maximum illuminance without increasing the crosstalk area.

Further, the second stereoscopic display device according to the present invention includes a light source, a display screen, a parallax barrier installed on the observer side of the display screen, and a large number of devices arranged between the display screen and the light source. 1. A stereoscopic display device comprising a lattice-shaped entrance-side barrier in which slits are arranged and separating an image on a display screen, wherein N is a number of viewpoints and M is a natural number smaller than the number of viewpoints determined by the position of the parallax barrier. , L is the horizontal pixel pitch of the display screen, the opening pitch of the parallax barrier is slightly smaller than NL / (N−M), and the opening pitch of the entrance-side barrier is slightly larger than NL. It is characterized in that the ratio of the distance between the barrier and the display pixel of the display screen and the distance between the entrance side barrier and the display pixel of the display screen is approximately M pair (NM).

The second stereoscopic display device will be described with reference to FIG.

The respective parameters in the second stereoscopic display device are the opening pitch B _{1 of} the parallax barrier 3 arranged on the viewer side of the display screen 2 composed of the liquid crystal panel,
The distance r ₁ (converted in air) between the parallax barrier 3 arranged on the observer side of the display screen 2 and the display pixel of the display screen 2, and the entrance side barrier 4 arranged on the light source 1 side of the display screen 2 Aperture pitch B ₂ , distance r ₂ between the entrance side barrier 4 arranged on the light source 1 side of the display screen 2 and the display pixel of the display screen ₂
(Converted value in air), distance R between parallax barrier 3 arranged on the observer side of display screen 2 and the observation position, inter-eye distance E
(= 65 mm) or the like, and among these parameters, as shown in FIG. 9, the following expressions (1) to (8) are established.

[0020]

[Equation 1] E: R + r ₁ + r ₂ = B ₁ : r ₁ + r ₂ = L: r ₂ (1)

[0021]

B ₂ : r ₁ + r ₂ = ML: r ₁ = (NM) E: R (2)

[0022]

[Equation 3] ∴r ₁ = MLR / (NM) E (3)

[0023]

∴r ₂ = L (R + r ₁ ) / (E−L) = LR (E + ML / (N−M)) / E (E−L) (4)

From the equation (1), B ₁ is given by the equation (5).

[0025]

## EQU5 ## B ₁ = L (r ₁ + r ₂ ) / r ₂ (5)

[0026]

[Equation 6] ∴B ₁ = NLE / ((N−M) E + ML) (6)

From the equation (2), B ₂ is given by the equation (7).

[0028]

[Equation 7] B ₂ = (NM) E (r ₁ + r ₂ ) / R (7)

[0029]

[Equation 8] ∴B ₂ = NLE / (E−L) (8)

Considering L << E, the barrier pitch B ₁ of the parallax barrier 3, the distance r ₁ and the barrier pitch B ₂ of the incident side barrier 4 and the distance r ₂ are as follows.

B ₁ is a value slightly smaller than NL / (NM), B ₂ is a value slightly larger than NL, r ₂ is approximately LR / E,
r ₁ becomes Mr ₂ / (NM).

Here, in B ₁ , NL / (NM)
A slightly smaller value means that N is N as a result of considering L << E.
It is the difference between L / (N−M) and the above formula (6), and the difference is NML ² / (N−M) {(N−M) E from both relational expressions.
+ ML}.

The value of B ₂ which is slightly larger than NL means that NL and (8)
The difference is NL ² /
(E−L).

Further, r ₂ is almost constant even if M and N are changed, but r ₁ depends on M / (NM). Therefore, if M / (NM) is reduced, the stereoscopic display device can be thinned.

In the second stereoscopic display device, in order to obtain a stereoscopic display with N viewpoints, the incident side barrier 4 arranged on the light source 1 side of the display screen 2 has one opening for N pixels. However, in the parallax barrier 3 arranged on the observer side of the display screen 2, one opening corresponds to N / (N−M) pixels below that.

In the second stereoscopic display device, the light-shielding portion of the entrance-side barrier 4 arranged on the side of the light source 1 of the display screen 2 is electrically selected to appear or disappear by using a liquid crystal material such as STN or TN. If possible, when the light-shielding portion appears, the stereoscopic display device has N viewpoints, and when the light-shielding portion disappears, the stereoscopic display device has a different number of viewpoints or a different number of viewpoints and an interocular distance.

Furthermore, when the light-shielding portion of the parallax barrier 3 on the viewing side of the display screen 2 can be selected to appear or disappear electrically by using a liquid crystal material such as STN or TN, the light source 1 side of the display screen 2 can be selected. If the light-shielding portions of both the incident-side barrier 4 arranged and the parallax barrier 3 arranged on the viewer side of the display screen 2 are eliminated, a planar image can be observed at the original resolution of the display screen.

The third stereoscopic display device of the present invention is
From the light source, the display screen, the parallax barrier installed on the observer side of the display screen, and the lattice-shaped entrance-side barrier in which a large number of slits arranged between the display screen and the light source are arranged at substantially equal pitches. In the stereoscopic display device for separating the image on the display screen, I is the number of viewpoints, J is a natural number smaller than the number of viewpoints determined by the position of the parallax barrier, and L is the pixel pitch in the horizontal direction of the display screen. if you did this,
The aperture pitch of the parallax barrier is slightly smaller than IL, the aperture pitch of the incident side barrier is slightly larger than IL / J, and the distance between the parallax barrier and the display pixel of the display screen, the incidence side barrier and the display screen are It is characterized in that the ratio of the distance to the display pixel is approximately J to (I-J).

Similar to the second stereoscopic display device described above, the following equations (9) to (16) are established among the parameters as shown in FIG.

[0040]

[Equation 9] JE: R + r ₁ + r ₂ = B ₁ : r ₁ + r ₂ = (I−J) L: r ₂ (9)

[0041]

B ₂ : r ₁ + r ₂ = L: r ₁ = E: R (10)

[0042]

[Equation 11] ∴r ₁ = LR / E (11)

[0043]

[Equation 12] ∴r ₂ = (I−J) L (R + r ₁ ) / ((JE− (I−J) L) = (I−J) LR (E + L) / (JE− (I−J)) L) E ... (12)

From the equation (9), B ₁ is as follows.

B ₁ = (I−J) L (r ₁ + r ₂ ) / r ₂ (13)

[0045]

[Equation 14] ∴ B ₁ = ILE / (E + L) (14)

From the equation (2), B ₂ is as follows.

[0047]

## EQU15 ## B ₂ = E (r ₁ + r ₂ ) / R (15)

[0048]

∴B ₂ = ILE / (JE− (I−J) L) (16)

Considering L << E, the barrier pitch B ₁ of the parallax barrier 3, the distance r ₁ and the barrier pitch B ₂ of the entrance-side barrier 4 and the distance r ₂ are as follows.

B ₁ is a value slightly smaller than IL, B ₂ is IL
A value slightly larger than / J, r ₁ = LR / E, and r ₂ is approximately (I−J) r ₁ / J.

Here, the value of B ₁ which is slightly smaller than IL means that IL and (1
4) and the difference is IL ² from both relational expressions.
/ (E + L).

Further, in B ₂ , a value slightly larger than IL / J is the difference between IL / J and the above equation (16) as a result of considering L << E above. becomes ^{I (I-J) L 2} / J (JE- (I-J) L).

Further, r ₁ does not depend on I and J, but r ₂
Depends on (I−J) / J. Therefore, (I-J) / J
By reducing the size, the stereoscopic display device can be made thinner.

In the third stereoscopic display device, when a stereoscopic display with the number of viewpoints I is obtained, the parallax barrier 3 arranged on the observer side of the display screen 2 has one aperture for I pixels. The incident side barrier 4 arranged on the light source 1 side of the display screen 2 has one opening corresponding to I / J pixels below that.

In the third stereoscopic display device, the light-shielding portion of the parallax barrier 3 arranged on the observer side of the display screen 2 is electrically selected to appear or disappear by using a liquid crystal material such as STN or TN. If possible, when the light-shielding portion appears, the stereoscopic display device has N viewpoints, and when the light-shielding portion disappears, the number of viewpoints or the number of viewpoints and the inter-eye distance are different.

Furthermore, when the light-shielding portion of the entrance-side barrier 4 on the light source 1 side of the display screen 2 can be made to appear and disappear electrically using a liquid crystal material such as STN or TN, the light source 1 side of the display screen 2 can be selected. If the light-shielding portions of both the entrance-side barrier 4 arranged on the display screen 2 and the parallax barrier 3 arranged on the viewer side of the display screen 2 are eliminated, a planar image can be observed at the original resolution of the display screen. .

A fourth stereoscopic display device according to the present invention comprises a light source, a display screen, a parallax barrier installed on the observer side of the display screen, and a large number of slits arranged between the display screen and the light source. A three-dimensional display device comprising lattice-shaped entrance-side barriers arranged at substantially equal pitches for separating images on a display screen, where the number of viewpoints is 2 and the pixel pitch in the horizontal direction of the display screen is L. The parallax barrier has an opening pitch slightly smaller than 2L, the entrance-side barrier has an opening pitch slightly larger than 2L, the distance between the parallax barrier and a display pixel on the display screen, the entrance-side barrier and the display pixel on the display screen. The ratio of the distances is about 1: 1.

Further, in this case, it is preferable that the aperture ratio of the parallax barrier and the aperture ratio of the incident side barrier are substantially the same, and if the aperture ratio of either barrier increases, the crosstalk region increases, which is preferable. Absent.

In the fourth stereoscopic display device of the present invention,
The aperture ratios of the parallax barrier and the entrance-side barrier can be freely selected based on the pixel aperture ratio. However, when the horizontal pixel pitch of the display screen is L and the pixel aperture width is 1, the parallax barrier aperture ratio is And the aperture ratio of the incident side barrier are both preferably around {(2L + 1) / 4L} × 100% or less.

One or both of the aperture ratio of the parallax barrier and the aperture ratio of the entrance-side barrier are {(2L + 1) / 4L}.
When it becomes larger than around 100%, a region where the left illuminance image and the right eye image overlap each other in the maximum illuminance region occurs in the crosstalk region, which is not preferable.

Both the aperture ratio of the parallax barrier and the aperture ratio of the entrance side barrier are {(2L + 1) / 4L} × 100%.
In the vicinity, the area that can be viewed stereoscopically with the maximum illuminance is wide enough,
The crosstalk area does not overlap with the maximum illuminance area, and since the illuminance of the left eye image and the right eye image decreases from the maximum illuminance of the other, the illuminance of the other increases, so Even if you move, the total illuminance will be constant.

Both the aperture ratio of the parallax barrier and the aperture ratio of the entrance-side barrier are {(2L + 1) / 4L} × 100%.
When the pixel aperture ratio is less than or equal to 50%, the pixel aperture ratio may be less than 50%. However, when the pixel aperture ratio is 50% or more, stereoscopic viewing is possible at maximum illuminance without increasing the crosstalk area. It is preferable because the area is enlarged.

In the fourth stereoscopic display device of the present invention, both the aperture ratio of the parallax barrier and the aperture ratio of the entrance side barrier are (l / L) × 100% or less, and 50 % Or more is preferable.

Either one or both of the aperture ratio of the parallax barrier aperture and the incident side barrier is 50%.
When it is below the range, the area where the maximum illuminance is obtained decreases, which is not preferable. Further, one or both of the aperture ratio of the aperture of the parallax barrier and the aperture ratio of the entrance side barrier is (l
/ L) × 100% is not preferable because the crosstalk region increases.

In the first to fourth stereoscopic display devices of the above invention, the center of the observer's pupil, the center of each pixel of the display screen, and the center of the parallax barrier opening corresponding to each pixel, The relationship with the center of the opening of the entrance-side barrier corresponding to each pixel is not particularly limited, but in order to reduce light loss, the parallax barrier, the display screen, and the grid-shaped barrier are arranged so that they are all aligned. Is preferably installed.

Further, in the above-mentioned first to fourth inventions, since a part of the light beam emitted from the light source is blocked by the light-shielding portion of the incident side barrier, there arises a problem that the light utilization rate is lowered. However, when the light source side surface of the incident side barrier is made of a material having a high reflectance such as a metal such as aluminum or white ink, the blocked light is reflected toward the light source side, and further a reflection mirror provided in the light source. While being repeatedly reflected by, the light can be directed to the light-transmitting portion of the incident-side barrier, which can increase the light utilization rate and increase the illuminance of the image.

Further, according to the present invention, there is also a problem that the light reflected on the rear surface of the liquid crystal panel or the light-shielding portion between pixels is reflected again on the incident side barrier and is incident on the pixels of the liquid crystal panel to lower the image contrast. However, if the liquid crystal panel side surface of the incident side barrier is formed of a material having a low reflectance, the light traveling from the liquid crystal panel to the incident side barrier is absorbed by the liquid crystal panel side surface of the incident side barrier. It is possible to prevent turbidity of color and deterioration of contrast by preventing the irregular incidence on the pixel.

[0068]

BEST MODE FOR CARRYING OUT THE INVENTION The following will specifically describe an embodiment of the present invention with reference to the drawings.

The stereoscopic display device according to the first embodiment of the present invention shown in FIG. 1 is a stereoscopic display device when the number of viewpoints is 2, and includes a light source 1, a liquid crystal panel 2, a front surface of the liquid crystal panel 2,
That is, the parallax barrier 3 arranged on the observer side,
The liquid crystal panel 2 includes an incident side barrier 4 arranged on the light source 1 side.

In order to increase the utilization rate of the light emitted from the light source 1, the center of the observer's pupil, the center of each opening 32 of the parallax barrier 3, the center of each pixel of the liquid crystal panel 2, and the incident light are incident. The centers of the openings 42 of the side barrier 4 are all arranged in a straight line.

As shown in FIG. 2, the entrance-side barrier 4 is formed by forming a stripe-shaped light-shielding portion 41 on a glass dry plate 43. For example, a photosensitizer is applied and exposed by a laser to blacken the stripes. Then, the non-photosensitive portion is removed, or it is formed by screen printing or the like.

The aperture ratio of the parallax barrier 3 (b ₁ /
B ₁ ) and the aperture ratio (b ₂ / B ₂ ) of the entrance-side barrier 4 are both 50%, and the aperture ratio of the liquid crystal panel 2 is 50%.
That's it. Where B ₁ is the parallax barrier 3
In the horizontal direction, b ₁ is the opening width of the opening 32, B ₂ is the horizontal barrier pitch of the entrance-side barrier 4,
b ₂ is the opening width of the opening 42.

As shown in FIG. 3, the relationship between the position of the pupil and the illuminance when the observer moves from the optimum observation position 61 to the left and right is within the range in which the left-eye image 22 is observed, as indicated by the solid line, for example. Then, there is a region of maximum illuminance in the left-right direction from the optimum observation position 61, and it decreases linearly on both sides.

When the observer further moves from the optimum observation position 61 to the left and right, the right eye image 21 is continuously observed in the same illuminance distribution in the range where the left eye image 22 is observed. Differently, the maximum illuminance can be obtained without the crosstalk area, and the range in which the maximum illuminance is obtained is increasing.

In the above embodiment, the incident side barrier 4 is formed by laminating the aluminum thin film 44 and the chromium thin film 45 on the glass substrate 43 and forming them in a stripe shape by etching as shown in FIG. 4, for example. For example, as shown in FIG. 5, an aluminum thin film 43 and a chromium oxide thin film 46 may be formed on a glass substrate 43 and formed in stripes by etching.

When the incident side barrier 4 shown in FIGS. 4 and 5 is used, the incident side barrier 4 is arranged so that the aluminum thin film 44 side faces the light source 1, and as shown in FIG.
The aluminum thin film 44 allows the light source 1 to shield the light 4
1 is reflected by the light source 1 side, and the light source 1
By guiding the light to the openings 42 between the light shielding portions 41 of the entrance barrier 4 while repeating the reflection by the inner reflection surface, the light utilization rate is increased and the illuminance at the observation position is increased.

Further, the chromium thin film 45 and the chromium oxide thin film 46.
Absorbs a light ray 81 emitted from the light source 1 and reflected by the liquid crystal panel 2, and prevents the light ray 81 from being again incident irregularly on the liquid crystal panel 2, thereby causing color turbidity, deterioration of contrast, and image It is possible to prevent adverse effects such as disturbance of the image (mixing of left and right images).

It should be noted that instead of the aluminum thin film 44, printing of white ink can be used to obtain the effect of increasing the light utilization rate. Further, by printing the black ink on top of the white ink, it is possible to further prevent the image from being adversely affected. However, it is difficult to completely overlap the printing of white ink with the printing of black ink, so if the stripe width of black ink is narrower than the stripe width of white ink, the effect does not decrease significantly if it is within the range. good.

In the stereoscopic display device according to the second embodiment of the present invention shown in FIG. 7, the aperture ratio (b of the parallax barrier 3 is
₁ / B ₂₎ of the both horizontal pixel pitch of the liquid crystal panel 2 to the opening of the incident-side barrier 4 (b ₂ / B ₂₎ is L, if the pixel aperture width l, (l / L) × 100%, and the aperture ratio (l / L) of the liquid crystal panel 2 is 50% or more.

Since the other constructions, operations and effects of this embodiment are the same as those of the above-mentioned first embodiment, their description will be omitted to avoid duplication.

In this embodiment, since the aperture ratio of the parallax barrier 3 and the aperture ratio of the entrance side barrier 4 are both larger than 50%, the observer can move from the optimum observation position 61 to the left and right direction as shown in FIG. When moving to, for example, a crosstalk region 63 with the right-eye image 21 is generated in a region where the illuminance of the left-eye image 22 decreases. However, if the crosstalk region 63 has the same size as the conventional one, a region where the maximum illuminance is obtained. 62
Will be larger than before.

In the third embodiment of the present invention shown in FIG.
Opening ratio of parallax barrier 3 (b ₁/ B₂) And the incident side
Rear 4 aperture ratio (b₂/ B₂) Together with water of the liquid crystal panel 2
Let the pixel pitch in the horizontal direction be L and the pixel aperture width be 1
For example, {(l + 2L) / 4L)} × 100%
Therefore, the aperture ratio of the liquid crystal panel 2 is set to 50% or more.

Since the other constructions, functions and effects of this embodiment are the same as those of the above-mentioned embodiments, their description will be omitted to avoid duplication.

In this embodiment, when the observer moves from the optimum observation position 61 in the left-right direction, the left-eye image 22 (right-eye image 2) having the maximum illuminance with the left eye (right eye) compared to the conventional example.
1) has a large observable range, and the left-eye image 2
2 (the image 21 for the right eye) the entire area where the illuminance is reduced cross-talks with the area where the illuminance of the image 21 for the right eye (image 22 for the left eye) is increased. However, the total illuminance at the pupil position, that is, the sum of the illuminance of the left-eye image 22 and the right-eye image 21 does not change at all.

In each of the above embodiments, the aperture ratio of the parallax barrier 3 and the aperture ratio of the entrance side barrier 4 are the same, but this is the most preferable in order to increase the light utilization rate. It does not prevent that the aperture ratio of the parallax barrier 3 and the aperture ratio of the incident side barrier 4 are made different.

A stereoscopic display device according to a fourth embodiment of the present invention shown in FIG. 11 is a stereoscopic display device using a liquid crystal panel and having four viewpoints, and includes a light source 1, a liquid crystal panel 2 and a liquid crystal panel. A parallax barrier 3 arranged on the front surface of the liquid crystal panel 2, that is, on the observer side, and an incident side barrier 4 arranged on the light source 1 side of the liquid crystal panel 2.

On the liquid crystal panel 2, the viewpoints A, B,
Pixel columns 1, 2, 3, 4 corresponding to C and D are displayed
You. In this embodiment, the number of viewpoints N is 4 and M is 2.
Therefore, the barrier pitch B of the parallax barrier 3₁ Is 4
L / (4-2) = value slightly smaller than 2L, incident side barrier
Barrier pitch B of 4₂ Is a value slightly larger than 4L, distance r
₂Is approximately LR / E, distance r₁Is r₂, That is, r₁: R₂
= 1: 1.

In the case of a stereoscopic display device having four viewpoints as in this embodiment, the incident side barrier 4 arranged on the light source 1 side of the liquid crystal panel 2 has four pixels (1, 2, 3). 4) corresponds to one opening 42, but the parallax barrier 3 arranged on the observer side of the liquid crystal panel 2 has 2 or less openings.
One opening 32 corresponds to each pixel.

Here, if the light-shielding portion 41 of the entrance-side barrier 4 arranged on the light source 1 side of the liquid crystal panel 2 is made electrically selectable to appear or disappear by using STN liquid crystal, the light-shielding portion 4
When 1 is made to appear, the stereoscopic display device has four viewpoints, and when the light shielding portion 41 is extinguished, the stereoscopic display device has two viewpoints as shown in FIG.

Furthermore, when the light-shielding portion 31 of the parallax barrier 3 on the observation side of the display screen can be selected to appear or disappear electrically using STN liquid crystal, the entrance-side barrier arranged on the light source 1 side of the display screen can be selected. 4 and the parallax barrier 3 arranged on the observer side of the display screen are eliminated, the planar image can be observed at the original resolution of the display screen.

A stereoscopic display device according to the fifth embodiment of the present invention shown in FIG. 13 shows a different example of a stereoscopic display device using a liquid crystal panel and having four viewpoints N, and M is 1. As in the fourth embodiment, the viewpoints A, B, and
Pixel columns 1, 2, 3, and 4 corresponding to C and D are displayed. In this embodiment, N is 4 and M is 1. Therefore, the barrier pitch B ₁ of the parallax barrier 3 is 4 L /
(4-1) = a little smaller than 4L / 3, the barrier pitch B ₂ of the incident side barrier 4 is a little larger than 4L, and the distance r
₂ almost LR / E, the distance r ₁ is r _2/3, i.e., r _1:
r ₂ = 1: 3. In this embodiment, the stereoscopic display device can be made thin.

Also in this embodiment, in the case of a stereoscopic display device having four viewpoints, the incident side barrier 4 arranged on the light source 1 side of the liquid crystal panel 2 has four pixels (1, 2, 3, 4)
1 corresponds to one opening 42, and the parallax barrier 3 arranged on the viewer side of the liquid crystal panel 2 corresponds to 4/3 pixels below that and one opening 32.

The stereoscopic display device according to the sixth embodiment of the present invention shown in FIG. 14 is a stereoscopic display device using a liquid crystal panel and the number of viewpoints I is 4, and each viewpoint A on the liquid crystal panel 2, Pixel columns 1, 2, 3, and 4 corresponding to B, C, and D are displayed. The sixth embodiment is similar to the above-mentioned fourth and fifth embodiments.
The arrangement of the pixel rows 1, 2, 3, and 4 is opposite to that of the above embodiment. In this embodiment, the number of viewpoints I is 4 and J is 2. Therefore, the barrier pitch B ₁ of the parallax barrier 3 is a little smaller than 4L, the barrier pitch B ₂ of the incident side barrier 4 is a little larger than 2L, and the distance r ₁ is LR /
E, the distance r ₂ is almost r ₁ , that is, r ₁ : r ₂ = 1: 1.

In the case of a stereoscopic display device having four viewpoints as in the sixth embodiment, the parallax barrier 3 arranged on the observer side of the liquid crystal panel 2 has four pixels (1, 2). ,
3 and 4) correspond to one opening 42, but the incident side barrier 4 arranged on the light source 1 side of the liquid crystal panel 2 corresponds to two pixels below it by one opening 32. .

Here, if the light-shielding portion 31 of the parallax barrier 3 arranged on the viewer side of the display screen can be made to appear and disappear electrically using STN liquid crystal, the light-shielding portion 3 can be selected.
When 1 is made to appear, the stereoscopic display device has four viewpoints, and when the light-shielding portion 31 is extinguished, the stereoscopic display device has two viewpoints as shown in FIG.

Furthermore, when the light-shielding portion 41 of the incident-side barrier 4 on the light source 1 side of the liquid crystal panel 2 can be selected to appear and disappear electrically using STN liquid crystal, the incident light arranged on the light source 1 side of the display screen can be selected. If the light-shielding portions of both the side barrier 4 and the parallax barrier 3 arranged on the viewer side of the display screen are eliminated, a two-dimensional image can be observed at the original resolution of the display screen.

The stereoscopic display device according to the seventh embodiment of the present invention shown in FIG. 16 shows a different example of a stereoscopic display device having a viewpoint number I of 4 using a liquid crystal panel, and J is 3. As in the sixth embodiment, the viewpoints A, B, and
Pixel columns 1, 2, 3, and 4 corresponding to C and D are displayed. In this embodiment, I is 4 and J is 3. Therefore, the barrier pitch B ₁ of the parallax barrier 3 is a little smaller than 4L, the barrier pitch B ₂ of the incident side barrier 4 is a little larger than 4L / 3, and r ₁ : r ₂ = 3: 1.
In this embodiment, the stereoscopic display device can be made thin.

In each of the above-mentioned embodiments, a part of the light beam emitted from the light source 1 is blocked by the light-shielding portion (light-shielding portion 41) of the entrance-side barrier 4, which causes a problem that the light utilization rate is lowered. The light source 1 of the incident side barrier 4
When the side surface is made of a metal such as aluminum or a material having a high reflectance such as white ink, the blocked light is reflected to the light source side and further reflected by the reflection mirror provided in the light source. The light can be directed toward the light-transmitting portion (opening 42) of the entrance-side barrier 4, whereby the light utilization rate can be increased and the illuminance of the image can be increased.

Further, in each of the above-mentioned embodiments, the light reflected by the rear surface of the liquid crystal panel 2 or the light-shielding portion between the pixels is reflected again by the incident side barrier 4 and enters the pixel of the liquid crystal panel 2 to improve the contrast of the image. Although there is a problem of lowering the incident side barrier 4, when the surface of the incident side barrier 4 on the liquid crystal panel 2 side is made of a material having a low reflectance, the light traveling from the liquid crystal panel 2 toward the incident side barrier 4 is reflected by the liquid crystal of the incident side barrier 4. By making the surface of the liquid crystal panel 2 absorb the light and prevent it from being irregularly incident on the pixels of the liquid crystal panel 2, it is possible to prevent color turbidity and deterioration of contrast.

[0100]

As described above, according to the present invention, the parallax barrier is installed on the viewer side of the display screen, and the lattice-shaped entrance side in which a large number of slits are arranged between the display screen and the light source. By installing the barrier, the range in which stereoscopic viewing is possible can be expanded without increasing crosstalk.

Even if a liquid crystal panel having a pixel aperture ratio of 50% or more in the horizontal direction is used, the maximum aperture ratio of the parallax barrier on the front side of the display screen and the aperture ratio of the entrance side barrier are appropriately designed. It is possible to simultaneously satisfy the condition that the illuminance is obtained and the condition that there is no crosstalk region.

Further, it is possible to make the area of crosstalk equal to or smaller than the area of the conventional art and at the same time increase the area of stereoscopic viewing at the maximum illuminance.

Further, by setting the crosstalk region as the entire range where the images corresponding to the left and right eyes can be seen outside the range where stereoscopic vision is possible at the maximum illuminance, the total illuminance does not change when the observer moves in the left and right directions. In such a case, the area in which stereoscopic vision is possible with the maximum illuminance can be made larger than in the conventional case.

In the present invention, particularly when the light-source-side surface of the light-shielding portion of the entrance-side barrier is made of a material having a high reflectance, the light incident on the light-shielding portion is reflected toward the light source side, and the light-reflecting surface of the light source is further reflected. It is possible to repeatedly guide the light to the light-transmitting portion of the entrance-side barrier, increase the light utilization rate, and increase the illuminance at the observation position.

Further, in the present invention, particularly when the surface of the light-shielding portion of the entrance side barrier on the liquid crystal panel side is made of a material having a low reflectance, the light reflected on the liquid crystal panel surface is on the liquid crystal panel side of the light shielding portion. It is possible to prevent the light from being further reflected by the surface and randomly entering the pixels of the liquid crystal panel, and to prevent adverse effects such as clouding of the color and deterioration of the contrast.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a perspective view of an entrance-side barrier according to the first embodiment of the present invention.

FIG. 3 is a characteristic explanatory diagram of the first embodiment.

FIG. 4 is a perspective view of another entrance-side barrier of the present invention.

FIG. 5 is a perspective view of another entrance-side barrier of the present invention.

FIG. 6 is an explanatory view of the function of another entrance-side barrier and another entrance-side barrier of the present invention.

FIG. 7 is a characteristic explanatory diagram of the second embodiment of the present invention.

FIG. 8 is a characteristic explanatory view of the third embodiment of the present invention.

FIG. 9 is a configuration diagram illustrating the principle of a multi-view stereoscopic display device according to the present invention.

FIG. 10 is a configuration diagram illustrating the principle of a multi-view stereoscopic display device according to the present invention.

FIG. 11 is a configuration diagram of a fourth embodiment of the present invention.

FIG. 12 is a configuration diagram of another embodiment different from the fourth embodiment described above.

FIG. 13 is a configuration diagram of a fifth embodiment of the present invention.

FIG. 14 is a configuration diagram of a sixth embodiment of the present invention.

FIG. 15 is a configuration diagram of another embodiment different from the sixth embodiment.

FIG. 16 is a configuration diagram of a seventh embodiment of the present invention.

FIG. 17 is a configuration diagram of a conventional example.

FIG. 18 is a characteristic explanatory diagram of a conventional example.

FIG. 19 is a characteristic explanatory diagram of another conventional example.

FIG. 20 is a characteristic explanatory diagram of another conventional example.

[Explanation of symbols]

 1 Light source 2 Display screen 3 Parallax barrier 4 Incident side barrier

Claims (12)

[Claims] 1. A stereoscopic display device comprising a light source, a display screen, and a parallax barrier installed on the observer side of the display screen, wherein the display screen and the light source are separated by a parallax barrier. A three-dimensional display device having a lattice-shaped entrance-side barrier with a large number of slits arranged therebetween. 2. A light source, a display screen, a parallax barrier installed on the observer side of the display screen, and a lattice-shaped entrance-side barrier having a large number of slits arranged between the display screen and the light source. A stereoscopic display device for separating an image on a display screen, wherein N is the number of viewpoints, M is a natural number smaller than the number of viewpoints determined by the position of the parallax barrier, and L is the pixel pitch in the horizontal direction of the display screen. In such a case, the opening pitch of the parallax barrier is slightly smaller than NL / (NM),
The opening pitch of the entrance-side barrier is slightly larger than NL,
A stereoscopic display device, wherein a ratio of a distance between the parallax barrier and a display pixel on a display screen and a distance between the incident side barrier and a display pixel on the display screen is approximately M pair (NM). 3. A light source, a display screen, a parallax barrier installed on the observer side of the display screen, and a lattice-shaped entrance-side barrier having a large number of slits arranged between the display screen and the light source. A stereoscopic display device for separating an image on a display screen, wherein I is the number of viewpoints, J is a natural number smaller than the number of viewpoints determined by the position of the parallax barrier, and L is a horizontal pixel pitch of the display screen. In such a case, the opening pitch of the parallax barrier is slightly smaller than IL, the opening pitch of the incident side barrier is slightly larger than IL / J, the distance between the parallax barrier and the display pixel of the display screen, and the incident side barrier. And the ratio of the distance between the display screen and the display pixel is almost J
A stereoscopic display device characterized by being a pair (I-J). 4. The stereoscopic display device according to claim 1, wherein at least one of the parallax barrier and the entrance-side barrier has a light-shielding portion that is selectable to appear or disappear. . 5. A grid-like structure in which a light source, a display screen, a parallax barrier installed on the observer side of the display screen, and a large number of slits arranged between the display screen and the light source are arranged at substantially equal pitches. A stereoscopic display device comprising an entrance-side barrier and separating images on a display screen, where the number of viewpoints is 2 and the pixel pitch in the horizontal direction of the display screen is L, the aperture pitch of the parallax barrier is 2L or more. The aperture pitch of the incident side barrier is slightly larger than 2L, and the ratio of the distance between the parallax barrier and the display pixel of the display screen and the distance between the incident side barrier and the display pixel of the display screen is approximately 1: 1. A stereoscopic display device characterized in that 6. The pixel aperture ratio in the horizontal direction of the display screen is 50.
% Or more, The stereoscopic display device of Claim 5 characterized by the above-mentioned. 7. The horizontal pixel pitch of the display screen is L,
When the pixel aperture width is 1, both the aperture ratio of the parallax barrier and the aperture ratio of the incident side barrier are (l / L) × 100.
%, And 50% or more. The stereoscopic display device according to claim 5, wherein 8. The horizontal pixel pitch of the display screen is L,
When the pixel aperture width is 1, both the aperture ratio of the parallax barrier and the aperture ratio of the incident side barrier are {(2L + 1) / 4.
The stereoscopic display device according to claim 5, wherein L} × 100%. 9. The stereoscopic display device according to claim 5, wherein the aperture ratio of the parallax barrier and the aperture ratio of the entrance-side barrier are substantially the same. 10. The center of the observer's pupil, the center of each pixel of the display screen, the center of the parallax barrier opening corresponding to each pixel, and the center of the entrance-side barrier opening corresponding to each pixel. 10. The stereoscopic display device according to claim 1, wherein the parallax barrier, the display screen, and the grid-shaped barrier are installed so that and are all aligned. 11. The stereoscopic display device according to claim 1, wherein the light-shielding portion of the parallax barrier is formed of a material having high reflectance. 12. The light source side of the light shielding portion of the entrance side barrier is made of a material having a high reflectance, and the display screen side is made of a material having a low reflectance. 3D display device.