JPH11109286A - Stereoscopic video display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stereoscopic video display device dissolving sense or incongruity when a right eye image on a picture is replaced with a left eye image corresponding to a head position of an observer. SOLUTION: This display device gives a Liquid crystal panel 1 a light source while striping, and makes a stereoscopic view possible, and a back-light part is composed of a linear light source, a lenticular screen 6 arranged forward it and a diffusion plate 7 image forming the image of the linear light source arranged forward it by the lenticular lens of this screen 6. Further, the device is provided with a first light source 5a alternately observing the right eye image and the left eye image displayed with the stripe image of the linear light source image formed on the diffusion plate 7 every other one vertical line of the liquid crystal panel 1 at a pitch of an inter-eye distance E on an optimum observing position of an observer and a second light source 5b supplying the normal right eye image or left eye image to the position horizontally moved from the optimum observing position by E/2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional image display device capable of observing a three-dimensional image without using special glasses, and more particularly to a right-eye image on a screen corresponding to the position of the observer's head. The present invention relates to a three-dimensional image display device capable of eliminating a sense of discomfort when replacing a left-eye image.

[0002]

2. Description of the Related Art Conventionally, as a device for displaying a stereoscopic image without using special glasses, a parallax barrier or a lenticular lens is arranged on a viewer side of a display screen of a display panel such as a liquid crystal panel, and the display screen is displayed. In some cases, light from a right-eye image and a left-eye image alternately displayed for each vertical line is separated so that a stereoscopic image can be viewed.

Further, by separating light for the left eye and light for the right eye into a transmissive display panel such as a liquid crystal panel, a stereoscopic image is displayed without using special glasses. There are also devices.

In the above-described stereoscopic video display device, an optimum observation position is set as shown in FIGS.
That is, the optimal observation position at which the right-eye image and the left-eye image converge is set to a position separated by the optimal observation distance D from the stereoscopic video display device 200. In the optimal observation distance D and a predetermined range before and after the optimal observation distance D, a diamond-shaped region R for observing the right-eye image and a diamond-shaped region L for observing the left-eye image are alternately provided for each inter-eye distance E of the observer. Exists. Then, at the position a where the right eye 2R of the observer 2 is in the region R and the left eye 2L is in the region L, stereoscopic stereopsis is possible. Conversely, at the position b where the right eye 2R of the observer 2 is in the L region and the left eye 2L is in the R region, stereopsis cannot be observed due to reverse vision.

Therefore, in order to widen the area where the stereoscopic image can be observed, for example, as shown in FIGS. 8 and 9, a sensor 201 for detecting the position of the head of the observer 2 is provided. When it is detected that the position of the head is located in the pseudoscopic region, the stereoscopic image display device 2
A stereoscopic image display device provided with an image switching means for exchanging the right-eye image and the left-eye image of the display panel No. 00 has been proposed (for example, see Japanese Patent Application No. 7-253888).

FIG. 8 shows a state in which the head of the observer 2 is in a position where stereoscopic stereoscopic vision is possible. In the region R where the right eye 2R can observe the right eye image, the left eye 2L observes the left eye image. It is located in a region L where it can be formed. FIG. 9 shows a state in which the observer 2's head is located at a position where a reverse vision is performed in the related art. However, the right-eye image and the left-eye image on the display panel of the three-dimensional image display device 200 are replaced with each other, The region R where the eye 2R can observe the right-eye image and the region L where the left-eye image can be observed are exchanged, and as a result, the region R where the right eye 2R can observe the right-eye image
In addition, the left eye 2L is located in the region L where the left eye image can be observed, thereby enabling stereoscopic stereoscopic vision.

[0007]

As described above, in the three-dimensional image display device in which the right-eye image and the left-eye image displayed on the display panel of the three-dimensional image display device 200 are exchanged,
When the observer's eye is shifted to the reverse viewing position, the observer can observe the appropriate video by exchanging the left and right images. However, before moving from the position of normal vision to the position of reverse vision, as shown in FIG. 10, a crosstalk region or a black region between the region R in which the right-eye image can be observed and the region L in which the left-eye image can be observed. There is an area and the observer sees a blurred double image or moiré in this area because the crosstalk area or the black area enters the eyes while the right and left eye images are swapped. There is a problem that the user feels something uncomfortable after watching the video. In the present invention, a region where a crosstalk region or a black region enters an eye and a viewer observes a blurred image or a moiré-like image is collectively referred to as a moiré region.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a three-dimensional image display device capable of eliminating a sense of discomfort when a right-eye image and a left-eye image are interchanged on the screen in accordance with the position of the observer's head. is there.

[0009]

SUMMARY OF THE INVENTION The present invention provides a stereoscopic image display device which enables a stereoscopic view by providing a light source in a stripe form to a liquid crystal panel for alternately displaying pixels for the left eye and pixels for the right eye. The backlight unit is constituted by a linear light source, a lenticular screen disposed in front thereof, and a diffusion plate which forms an image of the linear light source disposed further in front thereof by the lenticular lens, A stripe image of a linear light source formed on the diffusion plate is formed by a right eye image and a left eye image displayed on every other vertical line of the liquid crystal panel at an optimum observation position of the observer at a pitch of the interocular distance E. The first to enable observation alternately at
And a position shifted in the E / 2 horizontal direction from the optimum observation position, that is, a boundary portion between a position where the right light image and the left eye image are supplied to the space at a pitch E by the first light source. The second, which can supply a normal right-eye image or left-eye image,
And a light source.

[0010] By providing two light sources capable of supplying a stereoscopic image to the observer, the supply of the stereoscopic image is geometrically impossible in one system. On the other hand, it is possible to guarantee supply of a stereoscopic image in the other system. By using one system, the stereoscopic view is possible even in the reverse viewing area by switching and displaying the right eye image and the left eye image according to the observer's position, as well as the normal viewing area generated when the light source is striped. But
By preparing two systems of such light sources, turning on the optimal light source according to the position of the observer, and switching the image displayed on the liquid crystal panel, the observer can be moved in all positions with respect to the lateral movement of the observer. Observation of a stereoscopic image becomes possible.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing the principle of stereoscopic vision in an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a liquid crystal panel for displaying an image, and reference numerals 2 and 3 denote a front glass substrate and a rear glass substrate of the liquid crystal panel 1, respectively. On the liquid crystal panel 1, a right-eye image and a left-eye image are displayed every other vertical line. In the figure, R indicates a right-eye image and L indicates a left-eye image.

On the back of the liquid crystal panel 1, two systems of linear light sources 4a and 4b are arranged. In FIG. 1, one line is shown for each, but a plurality of lines may be arranged by design. In the state of FIG. 1, the light source 4a is turned on and the light source 4b is turned off corresponding to the position of the observer 8.

A light-shielding plate 5 is arranged on the front of the linear light sources 4a and 4b in order to increase the accuracy of the line width of the linear light sources 4a and 4b. The light shielding plate 5 is provided with openings 5a and 5b corresponding to the light sources 4a and 4b, respectively. Therefore, the light from the lit linear light source 4a is emitted toward the liquid crystal panel 1 only from the opening 5a of the light shielding plate 5.

In front of the linear light sources 4a and 4b,
A lenticular screen 6 in which lenticular lenses for reducing the images of the light sources 4a and 4b and forming an image at the same pitch are arranged in a horizontal direction is arranged.
A diffusion plate 7 for forming the image is disposed in front of the diffusion plate 7. Therefore, an image of the opening 5 a emitting light, that is, a light-emitting stripe image 7 a is formed on the diffusion plate 7 at a pitch corresponding to the pixel pitch of the liquid crystal panel 1. As shown in FIG. 1, the right-eye image R displayed on the liquid crystal panel 1 is formed by the stripe-shaped light-emitting stripe image 7a.
And the left-eye image L are respectively observed only by the corresponding eyes 9 and 10 of the observer 8, and the observer 8 can recognize the stereoscopic image.

Next, an optical design according to the embodiment of the present invention will be described.

As shown in FIG. 2, the distance between the eyes of the observer 8 is E, the optimal observation distance is D, the pixel pitch of the liquid crystal panel 1 is P, the pixel opening width of the liquid crystal panel 1 is M, and the diffusion between the liquid crystal panel 1 and the liquid crystal panel 1 is M. The distance from the plate 7 to C, the distance between the diffusion plate 7 and the center of the lens of the lenticular screen 6 is B, the pitch of the lens of the lenticular screen 6 is R, the focal length of the lens of the lenticular screen 6 is F, The distance between the center of the lens and the light-shielding plate 5 is A, the width of the opening 5a (5b) of the light-shielding plate 5 is U, and the same image is formed on the diffusion plate 7 by using adjacent lenticular lenses. , The distance between the linear light sources in the first light source 4a (the second light source 4b) is Y, the distance between the first light source 4a and the second light source 4b is W ′, and the first image formed on the diffusion plate 7 is formed. Light source 4a (second light source 4b ) Is Q, the width of the first light source 4a (second light source 4b) formed on the diffusion plate 7 is T,
When the shift amount of the image of the second light source 4b with respect to the image of the first light source 4a formed on the diffusion plate 7 is S, the following equation is established.

[0018]

E: (D + C) = P: C Q: (D + C) = 2P: D 1 / A + 1 / B = 1 / FS S: C = E / 2: D W ': A = (Q + S): B R: A = Q: (A + B) T: B = U: A

From the above equation 1, the following relationship is obtained.

[0020]

D = C (E−P) / P Q = 2EP / (E−P) S = EP / {2 × (E−P)} A = BF / (B−F) R = 2EPA / ｛ (A + B) × (E−P)｝ Y = QA / B = 2 EPA / {(E−P) × B}

The above Y is a case where adjacent lenticular lenses are used, but actually, it is not always necessary to use adjacent lenses. For example, as shown by X in FIG. In some cases, it is necessary to use a lens that is further away by one so that the second light source 4b does not overlap with the second light source 4b. Therefore, generally, the first light source 4a
The pitch X of the opening 5a (light source) in the (or the second light source 4b) is as follows.

[0022]

X = 2n EPA / {(E−P) × B} (where n is an arbitrary integer, n = one when there is one line light source)
0)

Similarly, W 'is as follows in FIG.

[0024]

## EQU4 ## W '= A (Q + S) / B

However, for the same reason as the above X, it is generally expressed as follows.

[0026]

W = A (NQ + S) / B = AEP (4N + 1) / {2B (E−P)} (where N is an arbitrary natural number)

The first light source 4a or the second light source 4
The linear light sources constituting b need to satisfy the above two equations, but cannot be arranged in an overlapping manner.

The light emitting portion ratio T / Q of the stripe light source 7a formed on the diffusion plate 7 is disclosed in Japanese Patent Laid-Open No. 7-287196.
As described in Japanese Patent Application Laid-Open Publication No. H10-209, it is necessary to satisfy the following relationship because it is excellent in property to make the opening ratio of the light shielding plate 5 equal.

[0029]

When P / 2 ≦ M <2P / 3 (PM) / (2P) ≦ T / Q ≦ M / (2P) Therefore, E (PM) / (E−P) ≦ T ≦ EM / (E−P) When M <P / 2 T / Q ≦ (PM) / (2P) Therefore, T ≦ E (PM) / (E−P) 2P / 3 ≦ M < At the time of P (PM) / (2P) <T / Q ≦ (PM) / P Therefore, E (PM) / (EP) <T ≦ 2E (PM) / (E
-P)

Next, a method of switching images displayed on the liquid crystal panel 1 and the light sources 4a and 4b according to the present invention will be described. The lighting of the light source 4a or 4b and the display state of the liquid crystal panel 1 in FIG.

First, as shown in FIG. 4, when the observer 8 moves rightward in the figure from the reference position in FIG. 1 by the distance E between eyes, the observer 8 is in a state of reverse vision with respect to the reference state. What is necessary is just to switch and display the right eye image and the left eye image displayed on the panel 1.

Next, as shown in FIG. 5, when moving from the reference position in FIG.
Since the observer 8 becomes a boundary where the right eye image or the left eye image can be observed with respect to the reference state, the observer 8 cannot observe a normal image in this state. Therefore, the first
The light source 4a is turned off and the second light source 4b is turned on. With this control, a normal image can be observed even in a place where the observer 8 has moved to the right by E / 2. Since the right-eye image and the left-eye image observed by the observer 8 remain the same as the reference state, the display on the liquid crystal panel 1 is continued.

Next, as shown in FIG. 6, when the observer moves leftward in the figure by E / 2 of the interocular distance from the reference state shown in FIG. On the other hand, the first light source 4a is turned off and the second light source 4b is turned on because the boundary is where the right eye image or the left eye image can be observed. With this control, a normal image can be observed even in a place where the observer 8 has moved to the left side of E / 2. However, since the right-eye image and the left-eye image observed by the observer are reversed, it is necessary to switch the right-eye image and the left-eye image displayed on the liquid crystal panel 1 together.

In the embodiment of the present invention shown in FIGS. 1 to 6, when the light sources 4a and 4b are switched on and off, the appearance of the pixel at each center (optimum) position is shown. However, as a region where the light sources 4a and 4b are switched, the observer 8 moves rightward or leftward (however, leftward) with respect to the center of the region where the first light source 4a supplies a stereoscopic image to the observer 8. If the movement is-(minus), the light source is switched to the second light source 4b when the movement is performed by the amount shown in the following equation.

[0035]

(4n-3) E / 4 <X <(4n-1) E / 4
(N; integer)

When moving by the amount shown in the following equation, the first
It is better to return to the lighting of the light source 4a.

[0037]

(4n-1) E / 4 ≦ X ≦ (4n + 1) E / 4
(N; integer)

Further, as described above, in each state, the liquid crystal panel 1 corresponds to the right eye 9 and the left eye 10 of the observer 8 so that an optimal image is supplied to each eye. It is also necessary to display the right-eye image and the left-eye image at the same time. FIG.
Table 1 shows the switching of the light sources 4a and 4b and the display state of the liquid crystal panel 1 in FIGS.

[0039]

[Table 1]

The loop of Table 1 is repeated in the further right and left regions of the table.

[0041]

As described above, according to the present invention,
With a simple configuration, it is possible to always supply a stereoscopic image with respect to the lateral movement of the observer.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the principle of stereoscopic vision in an embodiment of the present invention.

FIG. 2 is a schematic diagram showing design parameters in the embodiment of the present invention.

FIG. 3 is an explanatory diagram of a design method of a light source unit in the embodiment of the present invention.

FIG. 4 is a schematic diagram showing a display state of the stereoscopic video display device when an observer moves rightward by an interocular distance E in the embodiment of the present invention.

FIG. 5 is a schematic diagram showing a display state of the stereoscopic video display device when the observer moves rightward by E / 2 in the embodiment of the present invention.

FIG. 6 is a schematic diagram showing a display state of the stereoscopic video display device when the observer moves leftward by E / 2 in the embodiment of the present invention.

FIG. 7 is a diagram illustrating the principle of stereoscopic viewing in a conventional example.

FIG. 8 is a diagram illustrating the principle of stereoscopic viewing at a standard viewing position in another conventional example.

FIG. 9 is a diagram illustrating the principle of stereoscopic viewing at a reverse viewing position in another conventional example.

FIG. 10 is a principle diagram of observation in a crosstalk region of another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal panel 4a 1st light source 4b 2nd light source 5 Shield plate 6 Lenticular screen 7 Diffusion plate 8 Observer

Claims (15)

[Claims] A liquid crystal panel for alternately displaying pixels for the left eye and pixels for the right eye is provided with a light source in the form of stripes.
A stereoscopic video display device capable of stereoscopic vision, wherein a backlight unit forms an image of a linear light source, a lenticular screen disposed in front thereof, and an image of the linear light source disposed in front thereof. A first light source configured to provide a stereoscopic image to an observer located at a certain position, and a distance between eyes of the observer in the lateral direction from the specific position. A second light source capable of supplying a three-dimensional image to a position approximately one-half apart from the second light source. 2. The three-dimensional image display device according to claim 1, wherein the lighting of the two types of light sources is switched according to the position of the observer. 3. An optimum observation distance D is defined as follows, where E is the distance between the eyes of the observer, P is the pixel pitch of the liquid crystal panel, and C is the distance between the liquid crystal panel and the diffusion plate that forms the stripe image of the linear light source. The stereoscopic video display device according to claim 1, wherein D = C (E−P) / P. 4. A pitch Q of a stripe image of the first linear light source or the second linear light source formed on the diffusion plate, wherein Q = 2EP / (E−P). The three-dimensional image display device according to claim 1. 5. When the stripe image formed on the diffusion plate is switched from that of the first linear light source to that of the second linear light source, the moving amount S is as follows: S = EP / ｛ The stereoscopic image display device according to claim 1, wherein 2 × (E−P)｝. 6. When the pitch of the lens in the lenticular screen disposed below the diffusion plate is R, the focal length of the lens is F, and the distance between the lens and the diffusion plate is B, the distance between the lens and the light source is A. Then, R = AQ / (A + B) = 2 EPA / ｛(A + B) × (E
The stereoscopic video display device according to claim 1, wherein −P)｝ A = BF / (BF). 7. When the pitch of the linear light source in the first linear light source or the second linear light source is X, X = NQA / B = 2NEPA / {(E−P) × B} (where N The stereoscopic image display device according to claim 1, wherein: is an arbitrary natural number. 8. Assuming that the shift amount of the second linear light source with respect to the first linear light source is W, W = A (NG + S) / B = EPA (4N + 1) / {2B × (E−P)}. The three-dimensional image display device according to claim 1, wherein (N: any natural number). 9. The stereoscopic image display device according to claim 1, wherein the first linear light source and the second linear light source are discretely arranged. 10. When the width of a stripe image formed on the diffuser of the first linear light source and the second linear light source is T and the pixel aperture width of the liquid crystal panel is M, the M Is in the range of P / 2 ≦ M <2P / 3, T satisfies E (PM) / (E−P) ≦ T ≦ EM / (E−P). 10. The stereoscopic video display device according to any one of 1 and 9. 11. The first linear light source and a second linear light source.
When the width of the stripe image formed on the diffusion plate of the linear light source is T and the pixel opening width of the liquid panel is M,
The solid according to claim 1, wherein T satisfies T ≦ E (PM) / (E−P) when the M is in the range of M <P / 2. Video display device. 12. When the width of a stripe image formed on the diffuser of the first linear light source and the second linear light source is T and the pixel aperture width of the liquid crystal panel is M, the M Is in the range of 2P / 3 ≦ M <P, T is expressed as E (PM) / (E−P) <T ≦ 2E (PM) / (E
The stereoscopic video display device according to claim 1, wherein -P) is satisfied. 13. The three-dimensional object according to claim 1, wherein when the width of the first linear light source and the second linear light source is U, U = TA / B is satisfied. Video display device. 14. A system comprising means for detecting a lateral movement of a head of an observer, and determining whether the observer can supply an image with a first light source or an image with a second light source. Means for switching the lighting of the light source, and a right-eye image and a left-eye image alternately displayed on a vertical line on the screen of the liquid crystal panel so that a normal stereoscopic image is supplied to the observer's eyes. 14. The three-dimensional image display device according to claim 1, further comprising: means for switching and displaying. 15. The observer moves rightward or leftward with respect to a center point of an area for supplying a stereoscopic image to the observer with the first light source (however, leftward movement is defined as-(minus)). (4n-3) E / 4 <X <(4n-1) E / 4 (n;
The second light source is turned on when it has moved by an amount of (integer), and (4n-1) E / 4 ≦ X ≦ (4n + 1) E / 4 (n;
(Integer), the first light source is switched on, and the vertical line of the liquid crystal panel is provided so as to correspond to the right and left eyes of the observer and to supply an optimal image to each eye. 15. The stereoscopic video display device according to claim 1, wherein the right-eye image and the left-eye image are alternately displayed in a shape.