JP2021105724A - Stereoscopic image display device - Google Patents

Abstract

To provide a stereoscopic image display device that enables an observer to observe a stereoscopic image even when an observation position is shifted.SOLUTION: A stereoscopic image display device comprises: a screen that includes a light collection part and a light diffusion part arranged in a direction in which light passes; a first projector that emits first image light to the screen; a second projector that emits second image light to the screen; a detection part that detects the position of an observer; and a driving part that moves at least the light collection part of the screen on the basis of a result of detection performed by the detection part.SELECTED DRAWING: Figure 1

Description

The present invention relates to a stereoscopic image display device.

Conventionally, there is a stereoscopic image display device that allows an observer to observe a stereoscopic image by projecting two images having left-right parallax on a screen using two projectors (see, for example, Patent Document 1 below). In this stereoscopic image display device, the return position of the reflected light from the screen is controlled according to the viewpoint position of the observer so that the stereoscopic image can be visually recognized even when the viewpoint of the observer moves.

Japanese Unexamined Patent Publication No. 10-115878

However, since the stereoscopic image display device uses a regressive screen having a characteristic of returning the reflected light toward the light source as the screen, the return position of the reflected light cannot be controlled even if the position or orientation of the screen is changed. .. That is, with the above-mentioned conventional stereoscopic image display device, if the observation position of the observer shifts, the stereoscopic image cannot be observed well.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a stereoscopic image display device capable of observing a stereoscopic image even when the observation position is deviated.

According to the first aspect of the present invention, a screen including a condensing portion and a light diffusing portion arranged in a direction through which light passes, a projector for the right eye that emits first image light to the screen, and the screen. On the other hand, a second projector that emits the second image light, a detection unit that detects the position of the observer, and a drive unit that moves at least the condensing unit of the screen based on the detection result of the detection unit. A stereoscopic image display device comprising, is provided.

According to the stereoscopic image display device according to the first aspect, even if the observer's observation position deviates from a predetermined position, the observer can observe the stereoscopic image within an observable range by moving the condensing unit. Can position the eye. Therefore, the observer can stably observe the stereoscopic image even if the observation position is deviated.

In the first aspect, the condensing portion is a Fresnel lens, and in the light diffusing portion, the light diffusing angle in the first direction of the screen is smaller than the light diffusing angle in the second direction intersecting the first direction. It is preferable that the driving unit moves at least the condensing unit in the first direction.

According to this configuration, the size of the observable range in the first direction is narrower than the size of the observable range in the second direction. According to the present invention, the observable range can be moved in the first direction by moving the condensing unit in the first direction. Therefore, even when the observer's observation position is deviated in the first direction, the observer's eyes can be positioned within the observable range. Therefore, the observer can stably observe the stereoscopic image without worrying about the deviation of the observation position in the first direction.

In the first aspect, the condensing portion is a linear Fresnel lens, and in the light diffusing portion, the light diffusion angle in the step direction of the linear Fresnel lens is smaller than the light diffusion angle in the direction intersecting the step direction. It is preferable that the driving unit moves at least the condensing unit in the step direction.

According to this configuration, the size of the observable range in the step direction is narrower than the size of the observable range in the direction intersecting the step direction. If the present invention is adopted, the observable range can be moved in the step direction by moving the condensing portion in the step direction. Therefore, even if the observer's observation position shifts in the step direction, the observer's eyes can be positioned within the observable range. Therefore, the observer can stably observe the stereoscopic image without worrying about the deviation of the observation position in the step direction.

In the first aspect, it is preferable that the condensing portion is a Fresnel lens and the light diffusing characteristic of the light diffusing portion is isotropic.

According to this configuration, the light projected from the projector is condensed around the observer's eyes, so that the light utilization efficiency is improved. Therefore, power saving can be realized by suppressing the optical output of the projector.

In the first aspect, it is preferable that the screen further includes a reflecting member that reflects light transmitted through the condensing portion and the light diffusing portion.

According to this configuration, a reflective screen can be realized. Further, when the reflective screen is used, the observer and the projector are located on one side of the screen, so that the image display device can be used in a smaller space than when the transmissive screen is used.

In the first aspect, the image pickup element that images the observer and the first image light and the second image light emitted from the first projector and the second projector are transmitted or reflected and incident on the screen. The first projector and the second projector further include, and the first image light and the second image light corresponding to the image captured by the image pickup element are projected, and the half mirror is a half mirror. It is preferable that the first image light and the second image light reflected by the screen are reflected or transmitted to guide the observer.

According to this configuration, by moving the position of the observable range following the position of the observer, the observer can always observe his / her face three-dimensionally without worrying about the observation position. ..

The figure which shows the schematic structure of the image display device of 1st Embodiment. A side view showing the positional relationship between the projector, the screen and the observer. A plan view showing the positional relationship between the projector, the screen, and the observer. Sectional drawing which shows the structure of a screen. A front view and a cross-sectional view showing the configuration of a Fresnel lens. The figure which shows the diffusion characteristic of a diffusion sheet. A plan view conceptually explaining how the image for the right eye is viewed by the observer. A plan view conceptually explaining how the image for the left eye is viewed by an observer. A side view that conceptually explains how the image looks in the vertical direction of the observer. The figure which shows the relationship between the movement of a screen and the change of the observation range of an observer. The cross-sectional view which shows the structure of the screen of 2nd Embodiment. A front view and a cross-sectional view showing the configuration of a linear Fresnel lens. A side view that conceptually explains how the image looks in the vertical direction of the observer. The figure which shows the diffusion characteristic of the diffusion sheet used for the screen of 3rd Embodiment. The figure which shows the schematic structure of the image display device of 4th Embodiment. The cross-sectional view which shows the structure of the screen of 4th Embodiment. A plan view conceptually explaining how the image for the right eye is viewed by the observer. A plan view conceptually explaining how the image for the left eye is viewed by an observer. A side view that conceptually explains how the image looks in the vertical direction of the observer. The figure which shows the relationship between the movement of a screen and the change of the observation range of an observer. The figure which shows the schematic structure of the image display device of 5th Embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the drawings used in the following description, in order to make the features easier to understand, the featured parts may be enlarged for convenience, and the dimensional ratios of each component may not be the same as the actual ones. do not have.

(First Embodiment)
The image display device of the present embodiment projects the image light for the right eye and the image light for the left eye corresponding to the binocular disparity onto the screen, and observes the image light for the right eye and the image light for the left eye transmitted through the screen. It is a device that displays a stereoscopic image on the human eye.

FIG. 1 is a diagram showing a schematic configuration of an image display device 100 of the present embodiment. As shown in FIG. 1, the image display device 100 includes a projector 1R, a projector 1L, a screen 10, a drive unit 11, a position detection unit 12, and a control device 15.

FIG. 2 is a side view showing the positional relationship between the projectors 1R and 1L, the screen 10 and the observer, and FIG. 3 is a plan view showing the positional relationship.
As shown in FIGS. 2 and 3, the observer M visually recognizes the stereoscopic image by being located on the opposite side of the screen 10 from the two projectors 1R and 1L and in the center of the two projectors 1R and 1L. do.

The projector 1R and the projector 1L are, for example, suspended and fixed from the ceiling in the room where the image display device 100 is installed. The projector (projector for the right eye) 1R is a projector that projects the image light GR for the right eye onto the screen 10. The projector 1R is arranged on the right side with respect to the central axis 10c of the screen 10 when the light incident surface of the screen 10 is viewed in a plan view. In the present embodiment, the projector 1R corresponds to the "first projector" described in the claims, and the image light GR for the right eye corresponds to the "first image light" described in the claims.

The projector 1L is a projector that projects the image light GL for the left eye onto the screen 10. The projector 1L is arranged on the left side with respect to the central axis 10c of the screen 10 when the light incident surface of the screen 10 is viewed in a plan view. In the present embodiment, the projector 1L corresponds to the "second projector" described in the claims, and the image light GL for the left eye corresponds to the "second image light" described in the claims.

The projectors 1R and 1L have the same configuration, and differ only in that the image signals corresponding to the image light GR for the right eye and the image light GL for the left eye are input. Therefore, when the video signals input to each other are exchanged, the projector 1R can project the image light GL for the left eye on the screen 10, and the projector 1L can project the image light GR for the right eye on the screen 10.

In the present embodiment, the screen 10 is a transmissive screen that transmits light from the projectors 1R and 1L. The planar shape of the screen 10 has a rectangular shape. In the present embodiment, the screen 10 has a shape that is longitudinal along the left-right direction (first direction) of the observer M and is short along the vertical direction (second direction) of the observer M. In this embodiment, the left-right direction and the up-down direction are orthogonal (intersect).

FIG. 4 is a cross-sectional view showing the configuration of the screen 10. FIG. 4 corresponds to a cross section passing through the central axis 10c of the screen 10. As shown in FIG. 4, the screen 10 includes a Fresnel lens (condensing unit) 5 and a diffusing sheet (light diffusing unit) 6 from the light incident direction. The Fresnel lens 5 and the diffusion sheet 6 are integrally held via a frame member (not shown).

FIG. 5 is a front view of the Fresnel lens 5 viewed from the light incident direction and a cross-sectional view passing through the center of the Fresnel lens 5. As shown in FIG. 5, the Fresnel lens 5 is a lens obtained by dividing a plano-convex lens into a plurality of concentric regions, and has a sawtooth-like cross-sectional shape. As a result, the Fresnel lens 5 suppresses the thickness of the entire lens.
Based on such a configuration, the Fresnel lens 5 can be regarded as equivalent to a lens having functions of focusing and imaging like a convex lens. The sawtooth-shaped cross section can also be regarded as a prism.

In the present embodiment, the Fresnel lens 5 is arranged on the light incident surface side with respect to the diffusion sheet 6, but the Fresnel lens 5 may be arranged on the light emitting surface side. That is, as the screen 10, a structure in which the positions of the Fresnel lens 5 and the diffusion sheet 6 are reversed left and right can be adopted.

The diffusion sheet 6 is a member that diffuses the light transmitted through the Fresnel lens 5. In the present embodiment, the diffusion sheet 6 has anisotropy in light diffusion characteristics.

FIG. 6 is a diagram showing the diffusion characteristics of the diffusion sheet 6. In FIG. 6, the horizontal axis is the emission angle based on the incident angle, and the vertical axis is the light transmittance.

As shown in FIG. 6, the diffusion sheet 6 of the present embodiment has an anisotropic characteristic such that the half-width full-width is several degrees in the left-right direction and the half-width full-width is several tens of degrees in the vertical direction. That is, in the diffusion sheet 6, the diffusion angle in the horizontal direction (first direction) is smaller than the diffusion angle in the vertical direction (second direction).

The drive unit 11 makes the screen 10 movable. The drive unit 11 is composed of, for example, an actuator. In the present embodiment, the drive unit 11 is attached to the lower part (frame member (not shown)) of the screen 10. The drive unit 11 can move the entire screen 10 at least in the left-right direction.

In this embodiment, the position detection unit 12 is attached to the upper part of the screen 10. For example, the position detection unit 12 is composed of two ultrasonic sensors or the like installed on both sides of the upper part of the screen 10, and the position of the head of the observer M in the left-right direction, specifically, the observer's eyes (viewpoint). ) Position can be detected. The position detection unit 12 is electrically connected to the control device 15 and transmits the detection result to the control device 15.

The control device 15 controls the driving of each part configuration of the image display device 100. That is, the control device 15 controls the projectors 1R and 1L and the drive unit 11. In the present embodiment, the control device 15 controls the position of the screen 10 by the drive unit 11 based on the result transmitted from the position detection unit 12.

Subsequently, the operation of the image display device 100 of the present embodiment will be described.
First, the appearance of the image by the observer M will be described.
FIG. 7A is a plan view conceptually explaining how the image for the right eye is viewed by the observer M, and FIG. 7B is a plan view conceptually explaining how the image for the left eye is viewed by the observer. FIG. 7C is a side view conceptually explaining how the observer M sees the image in the vertical direction.

As shown in FIG. 7A, the image light GR for the right eye projected from the projector 1R is incident on the screen 10. In FIGS. 7A-C, the image light GR for the right eye shows only three rays, a central ray and left and right rays, in order to make the figure easier to see.

The image light GR for the right eye is refracted by the Fresnel lens 5 when passing through the screen 10. In the present embodiment, since the screen 10 includes the diffusion sheet 6 in addition to the Fresnel lens 5, each ray GR1 constituting the image light GR for the right eye is diffused in the horizontal direction (horizontal direction) by the diffusion sheet 6. The diffused light ray GR1 is shown by a chain double-dashed line.

Since the image light GR for the right eye is diffused by passing through the screen 10 in this way, the light ray GR1 is focused not on one point but on the range Re shown by the hatching in FIG. 7A. This range Re corresponds to the range in which the right eye image G1 can be observed. Hereinafter, the range Re is referred to as an observable range Re. In the present embodiment, the focus of the projector 1R is adjusted so that the image light GR for the right eye is imaged on the diffusion sheet 6.

As shown in FIG. 7B, the image light GL for the left eye projected from the other projector 1L is incident on the screen 10. In FIGS. 7A-C, the image light GL for the left eye shows only three rays, a central ray and left and right rays, in order to make the figure easier to see.

Each ray GL1 constituting the image light GL for the left eye is diffused in the left-right direction by the diffusion sheet 6. The diffused light ray GL1 is shown by a chain double-dashed line. Similarly, the image light GL for the left eye is diffused by passing through the screen 10, and the light ray GL1 is focused on the range Le shown by the hatching in FIG. 7B. This range Le corresponds to the range in which the left eye image can be observed. Hereinafter, the range Le is referred to as an observable range Le. In the present embodiment, the focus of the projector 1L is adjusted so that the image light GL for the left eye is imaged on the diffusion sheet 6.

In the present embodiment, the diffusion sheet 6 has a larger diffusion angle in the vertical direction than in the horizontal direction (see FIG. 6). Therefore, as shown in FIG. 7C, the observable ranges Re1 and Le1 in which the observer M can observe the image in the vertical direction are both wider than in the horizontal direction. The observable ranges Re1 and Le1 correspond to the ranges in which the light rays GR1 and GL1 are focused in the vertical direction, respectively.

Therefore, when the observer M is in the observation position where the right eye overlaps at least a part of the vertically long prismatic range formed by the overlap of the observable range Re and the observable range Re1, the screen 10 The image light GR for the right eye projected on the image G1 can be observed as the image G1 for the right eye.

Further, when the observer M is in the observation position where the left eye overlaps at least a part of the vertically long prismatic range formed by the overlap of the observable range Le and the observable range Le1, the screen 10 The image light GL for the left eye projected on the image G2 can be observed as the image G2 for the left eye.

In the present embodiment, since the right eye image G1 and the left eye image G2 have parallax, the observer M can observe the stereoscopic image with the naked eye.

By the way, while observing a stereoscopic image, for example, if the observation position of the observer M deviates from a predetermined position, the stereoscopic image may not be visible.

On the other hand, in the image display device 100 of the present embodiment, the observation position of the observer M is detected by the position detection unit 12. Then, as will be described later, the control device 15 moves the screen 10 based on the information regarding the observation position of the observer M, and positions the eye position of the observer M within the observable range.

Hereinafter, the relationship between the movement of the screen 10 and the change in the observation range of the observer M will be described with reference to FIG. Note that FIG. 8 will be described by taking the image light GL for the left eye as an example. That is, FIG. 8 is a view corresponding to the plan view of FIG. 7B.

As shown in FIG. 8, when the screen 10 is moved in the direction of the arrow, the center position of the Fresnel lens 5 also moves in the same direction. The observable range Le is located on a straight line passing through the center line of the image light GL for the left eye and the center of the Fresnel lens 5. Therefore, when the Fresnel lens 5 moves together with the screen 10 as described above, the observable range Le also moves in the same direction as the screen 10.

The moving distance D1 of the observable range Le is determined by the ratio of the sum of the distance from the projector 1L to the screen 10 and the distance from the projector 1L to the screen 10 and the distance from the screen 10 to the observer M. That is, when the above two distances are substantially equal, the moving distance D2 of the screen 10 is about half (1/2 times) the moving distance D1 of the observable range Re. That is, the drive unit 11 can move the observable range Le by a large distance (twice the distance) by moving the screen 10 by a small distance.

In the present embodiment, the control device 15 acquires the observation position (eye position) of the observer M in the left-right direction based on the transmission result from the position detection unit 12. Then, the control device 15 moves the screen 10 by the drive unit 11 so that the eyes of the observer M overlap the observable range Re.

Since the same applies to the image G1 for the right eye that can be seen by the right eye of the observer M, the description thereof will be omitted.

As described above, according to the image display device 100 of the present embodiment, even if the observation position of the observer M deviates from a predetermined position in the left-right direction, the screen 10 is appropriately moved in the left-right direction. Therefore, the eyes of the observer M can be positioned in the observable range.
Therefore, the observer M can stably observe the stereoscopic image even when the observation position is deviated.
Further, when the observation position shifts, the observer M automatically moves according to the shift of the observation position, so that it takes time and effort to search for and move the position where the image can be observed. Since there is no such image, you can comfortably observe the stereoscopic image.

The observation position of the observer M may shift in the vertical direction. In the present embodiment, the right eye image observable range is a long prismatic shape in the vertical direction. Therefore, the image display device 100 of the present embodiment allows the observer to observe the stereoscopic image without moving the screen 10 in the vertical direction even when the observation position of the observer M is deviated to some extent in the vertical direction. be able to.

When the observation position of the observer M is significantly deviated in the vertical direction (when the observer's eyes are out of the observable range), the observer M is moved by moving the screen 10 in the vertical direction by the drive unit 11. The observable range may be moved to the position of the eye.

(Second Embodiment)
Subsequently, the image display device according to the second embodiment will be described. The difference between the present embodiment and the first embodiment is the configuration of the screen. The same reference numerals are given to the configurations common to those of the first embodiment, and detailed description thereof will be omitted.

FIG. 9 is a cross-sectional view showing the configuration of the screen 20 of the present embodiment. FIG. 9 corresponds to a cross section passing through the central axis of the screen 20. As shown in FIG. 9, the screen 20 includes a linear Fresnel lens (condensing unit) 5A and a diffusion sheet 6 from the projected light incident direction.

The linear Fresnel lens 5A and the diffusion sheet 6 are integrally held via a frame member (not shown). That is, the screen 20 of the present embodiment has a linear Fresnel lens 5A instead of the Fresnel lens.

FIG. 10 is a front view of the linear Fresnel lens 5A viewed from the light incident direction and a cross-sectional view showing a cross section passing through the central axis of the linear Fresnel lens 5A. As shown in FIG. 10, the cross section of the linear Fresnel lens 5A in the left-right direction has the same shape (step shape) as the Fresnel lens 5 of the first embodiment, and has a planar shape in the vertical direction. That is, the linear Fresnel lens 5A has a condensing function in the left-right direction, but does not have a condensing function in the vertical direction and transmits light.

Also in the present embodiment, the diffusion sheet 6 is provided with respect to the linear Fresnel lens 5A so that the light diffusion angle in the step direction (horizontal direction) of the linear Fresnel lens 5A is smaller than the light diffusion angle in the vertical direction intersecting the step direction. Is placed. In the present embodiment, the drive unit 11 can move at least the linear Fresnel lens 5A in the step direction (left-right direction).

In the present embodiment, the linear Fresnel lens 5A is arranged on the light incident surface side with respect to the diffusion sheet 6, but the linear Fresnel lens 5A may be arranged on the light emitting surface side. That is, as the screen 20, a structure in which the positions of the linear Fresnel lens 5A and the diffusion sheet 6 are reversed left and right can be adopted.

Since the linear Fresnel lens 5A does not have a stepped shape in the vertical direction as described above, it has a planar shape in the vertical direction. Therefore, the linear Fresnel lens 5A is designed to specularly reflect external light from a ceiling lighting device or the like in the vertical direction. Therefore, the screen 20 having the linear Fresnel lens 5A is unlikely to be deteriorated in visibility due to the influence of the reflected light due to the external light.

Subsequently, the appearance of the image by the observer M when the screen 20 of the present embodiment is used will be described.
The diffusion characteristics in the left-right direction of the screen 20 are the same as those of the screen 10 of the first embodiment. Therefore, in the left-right direction, the observable range Re in which the right-eye image G1 can be seen and the observable range Le in which the left-eye image G2 can be seen have the same shape. Therefore, when the observation position moves in the left-right direction, the appearance of the right-eye image G1 and the left-eye image G2 by the observer M is the same (see FIGS. 7A and 7B).

On the other hand, in the present embodiment, since the condensing function by the linear Fresnel lens 5A does not work in the vertical direction of the screen 20, light is basically transmitted as it is without being condensed. Therefore, in the vertical direction, the observable ranges Re2 and Le2 as shown in FIG. 11 are formed by the light rays GR1 constituting the image light GR for the right eye and the light rays GL1 constituting the image light GL for the left eye.

That is, the size of the observable ranges Re2 and Le2 expands according to the size of the diffusion angle in the vertical direction of the diffusion sheet 6. Therefore, it is desirable that the diffusion sheet 6 of the present embodiment has a larger diffusion angle than that of the screen 10 of the first embodiment.

Even when the screen 20 of the present embodiment is used, even if the observation position of the observer M deviates from a predetermined position in the left-right direction, the screen 20 is appropriately moved in the left-right direction as in the first embodiment. By moving to, the eyes of the observer M can be positioned in the observable range. Therefore, the observer M can stably observe the stereoscopic image even when the observation position is deviated.

(Third Embodiment)
Subsequently, the image display device according to the third embodiment will be described. The difference between the present embodiment and the first embodiment is the configuration of the screen. Specifically, the screen of the present embodiment has a diffusion sheet having different diffusion characteristics from the screen 10 of the first embodiment. The same reference numerals are given to the configurations common to those of the first embodiment, and detailed description thereof will be omitted.

The screen of the present embodiment has a Fresnel lens and a diffusion sheet like the screen of the first embodiment. That is, the basic configuration of the screen of the present embodiment is the same as that of the screen 10 of the first embodiment.

FIG. 12 is a diagram showing the diffusion characteristics of the diffusion sheet used for the screen of the present embodiment. In FIG. 12, the horizontal axis is the emission angle with respect to the incident angle, and the vertical axis is the transmission characteristic. That is, it is a figure corresponding to FIG.

As shown in FIG. 12, the diffusion sheet of the present embodiment has substantially the same diffusion angle in the horizontal direction (first direction) and the vertical direction (second direction). That is, the light diffusion characteristics of the diffusion sheet of the present embodiment are isotropic.

In the screen of the present embodiment having such an isotropic diffusion characteristic, the size of the observable range in the vertical direction is as narrow as the observable range in the horizontal direction (see FIGS. 7A and 7B). Therefore, in the present embodiment, the drive unit 11 adds the screen in the left-right direction and allows the screen to move in the up-down direction as well.

In the present embodiment, the ultrasonic sensor constituting the position detection unit 12 described in the first embodiment is also installed in the lower part of the screen. As a result, the position of the observer's head, specifically the position of the observer's eyes (viewpoint), can be detected in the vertical direction in addition to the horizontal direction.

According to the present embodiment, the eyes of the observer M can be positioned within the observable range even when the observation position of the observer M deviates from a predetermined position in any of the up, down, left, and right directions. Therefore, the observer can stably observe the stereoscopic image without worrying about the deviation of the observation position in any of the top, bottom, left, and right.

Further, according to the configuration of the present embodiment, the light projected from the projectors 1R and 1L (the image light GR for the right eye and the image light GL for the left eye) is collected around the eyes of the observer M, so that the projector 1R, High light utilization efficiency can be realized by efficiently using the light emitted from 1L. Therefore, since the light output of the projectors 1R and 1L can be suppressed, the power saving of the entire image display device can be achieved.

(Fourth Embodiment)
Subsequently, the image display device according to the fourth embodiment will be described. The difference between the present embodiment and the first embodiment is the configuration of the screen. The same reference numerals are given to the configurations common to the above embodiments, and detailed description thereof will be omitted.

FIG. 13 is a diagram showing a schematic configuration of the image display device 101 of the present embodiment. As shown in FIG. 13, the image display device 101 includes a projector 1R, a projector 1L, a screen 30, a drive unit 11, a position detection unit 12, and a control device 15.

Since the screen 30 of the present embodiment is a reflective screen, the observer M faces the screen 30 and observes the image directly under the projectors 1R and 1L. That is, in the present embodiment, the direction of observing the screen 30 is opposite to that of the transmissive screen 10 shown in the first embodiment. Therefore, the arrangement of the projectors 1R and 1L with respect to the screen 30 is reversed.

Further, in the present embodiment, since the projected images of the projectors 1R and 1L are also reflected, the left and right sides are reversed. Therefore, it is necessary to invert the left and right of the image signal input to each of the projectors 1R and 1L. As a method of inverting the left and right of such an image signal, it is possible to cope with it by using a conventionally known inversion function built in the projectors 1R and 1L.

Specifically, the projector 1R is located on the left side with respect to the center of the screen 30 when the light incident surface of the screen 30 is viewed in a plane. The projector 1L is located on the right side with respect to the center of the screen 30 when the light incident surface of the screen 10 is viewed in a plane.

FIG. 14 is a cross-sectional view showing the configuration of the screen 30 of the present embodiment. FIG. 14 corresponds to a cross section passing through the central axis of the screen 30. As shown in FIG. 14, the screen 30 includes a Fresnel lens 5, a diffusion sheet 6, and a reflection mirror (reflection member) 7 from the projected light incident direction.

The Fresnel lens 5, the diffusion sheet 6, and the reflection mirror 7 are integrally held via a frame member (not shown). That is, the screen 30 of the present embodiment has the same configuration as the screen 10 of the first embodiment except that the reflection mirror 7 is included.

The reflection mirror 7 is a flat surface that reflects visible light, and is formed, for example, by depositing a reflective film on the surface of glass. By providing the reflection mirror 7, the screen 30 of the present embodiment functions as a front screen that reflects the projected light (image light GR for the right eye and image light GL for the left eye) from the projectors 1R and 1L.

In the present embodiment, the screen 30 is movable at least in the left-right direction by the drive unit 11. The drive unit 11 moves the screen 30 based on the detection result of the position detection unit 12, as in the first embodiment.

Subsequently, the appearance of the image by the observer M in the present embodiment will be described.
FIG. 15A is a plan view conceptually explaining how the image for the right eye is viewed by the observer M, and FIG. 15B is a plan view conceptually explaining how the image for the left eye is viewed by the observer M. FIG. 15C is a side view conceptually explaining how the observer M sees the image in the vertical direction. That is, FIGS. 15A, 15B, and 15C are diagrams corresponding to FIGS. 7A, 7B, and 7C, respectively.

As shown in FIG. 15A, when the image light GR for the right eye projected from the projector 1R is reflected by the screen 30, it is diffused by passing through the diffusion sheet 6 and condensed at a predetermined position by the Fresnel lens 5. NS. In FIGS. 15A-C, as in FIGS. 7A-7C, the image light GR for the right eye and the image light GL for the left eye show only three rays, the central ray and the left and right rays, in order to make the figure easier to see, and after diffusion. The light rays GR1 and GL1 are shown by a alternate long and short dash line.

As shown in FIG. 15A, since the image light GR for the right eye reflected by the screen 30 is diffused, each ray GR1 constituting the image light GR for the right eye is not a single point but is in the observable range Re in the left-right direction. Condensing.

Further, as shown in FIG. 15B, each ray GL1 constituting the image light GL for the left eye reflected by the screen 30 is focused in the observable range Le in the left-right direction.
Further, as shown in FIG. 15C, each ray GR1 constituting the image light GR for the right eye is focused on the observable range Re3 in the vertical direction, and each ray GL1 constituting the image light GL for the left eye is focused in the vertical direction. Focus on the observable range Le3.

In the present embodiment, since the light reflected by the screen 30 is transmitted through the diffusion sheet 6 twice, the diffusion angle is different from that of the transmission type screen 10 which transmits the diffusion sheet 6 only once, but the diffusion sheet 6 is diffused. If the angle is adjusted, the observable ranges Re3 and Le3 described above can be set to the same size as the observable ranges Re1 and Le1 of the first embodiment even in the reflective screen 30.

Here, the relationship between the movement of the screen 30 and the change in the observation range of the observer M will be described with reference to FIG. Note that FIG. 16 will be described by taking the image light GR for the right eye as an example.

As shown in FIG. 16, when the screen 30 is moved in the direction indicated by the arrow, the center position of the Fresnel lens 5 also moves in the same direction, so that the observable range Re of the image light GR for the right eye also moves in the same direction as the screen 10. Moving.

Further, the relationship between the observable range Re and the moving distance of the screen 30 is the same as that of the transmissive screen 10. That is, the moving distance D2 of the screen 30 is about half (1/2 times) the moving distance D1 of the observable range Re. That is, the drive unit 11 can move the observable range Re by a large distance (twice the distance) by moving the screen 30 by a small distance.

According to the image display device 101 of the present embodiment, even when the observation position of the observer M deviates from a predetermined position in the left-right direction, the reflective screen 30 is moved in the left-right direction to perform the first embodiment. Similar to the morphology, the observer M's eyes can be positioned within the observable range. Therefore, the observer M can stably observe the stereoscopic image even when the observation position is deviated.

Further, in the present embodiment, since the reflective screen 30 is used, the observer M and the projectors 1R and 1L are on the same side of the screen 30, so that the space is smaller than that when the transmissive screen is used. The image display device 101 can be used.

(Fifth Embodiment)
Subsequently, the image display device according to the fifth embodiment will be described. The same reference numerals are given to the configurations common to the above embodiments, and detailed description thereof will be omitted.

FIG. 17 is a diagram showing a schematic configuration of the image display device 102 of the present embodiment. As shown in FIG. 17, the image display device 101 of the present embodiment includes a projector 1R, a projector 1L, a screen 30, a drive unit 11, a position detection unit 16, a control device 17, a half mirror 18, and the like. It includes image pickup devices 19a and 19b and a housing 25. The housing 25 houses the projector 1R, the projector 1L, the screen 10, the drive unit 11, the position detection unit 16, and the half mirror 18.

In the present embodiment, the position detection unit 16 is attached to the housing 25. For example, the position detection unit 16 is composed of two ultrasonic sensors or the like installed at the left and right ends of the housing 25, and the position of the head of the observer M in the left-right direction, specifically, the observer's eyes (viewpoint). ) Position can be detected. The position detection unit 16 is electrically connected to the control device 17 and transmits the detection result to the control device 17.

The control device 17 controls the drive of each configuration of the image display device 102. That is, the control device 17 controls the projectors 1R and 1L and the drive unit 11. In the present embodiment, the control device 17 controls the position of the screen 30 by the drive unit 11 based on the result transmitted from the position detection unit 16.

The projector 1R, the projector 1L, and the screen 30 have the same positional relationship as the image display device 100 of the first embodiment. In the present embodiment, the projector 1R and the projector 1L are located below the screen 30 and are arranged so as to project the image light GR for the right eye and the image light GL for the left eye from the bottom to the top.

In the present embodiment, the half mirror 18 is arranged in the middle of the path toward the screen 30 for the image light GR for the right eye and the image light GL for the left eye projected from the projector 1R and the projector 1L.

In the present embodiment, the observer M observes the image at a position facing the half mirror 18. The image pickup devices 19a and 19b are composed of, for example, a CCD camera. The image pickup devices 19a and 19b and the observer M are arranged in a relationship similar to the arrangement of the projectors 1R and 1L and the screen 30 (see FIG. 13) in the fourth embodiment, and each camera has a horizontal optical axis. The observer M is imaged from different directions through the half mirror 18. Therefore, the image captured by the image pickup device 19a and the image captured by the image pickup device 19b are images corresponding to the difference between the two visual points.

The image pickup devices 19a and 19b are electrically connected to the control device 17. The control device 17 converts the image data transmitted from the image pickup devices 19a and 19b (each CCD camera) into an image signal, and transmits the image data to the projectors 1R and 1L, respectively.

In the present embodiment, the projector 1R projects the image light GR for the right eye toward the screen 30 based on the image signal (image captured by the image pickup device 19a) transmitted from the control device 17. Further, the projector 1L projects the image light GL for the left eye toward the screen 30 based on the image signal (image captured by the image pickup device 19b) transmitted from the control device 17. In the present embodiment, the image light GR for the right eye and the image light GL for the left eye pass through the half mirror 18 and enter the screen 30.

The image light GR for the right eye and the image light GL for the left eye reflected by the screen 30 are reflected toward the observer M by the half mirror 18. In the present embodiment, since the image light GR for the right eye and the image light GL for the left eye correspond to the binocular parallax, a stereoscopic image Z is generated on the screen 30. Therefore, the observer M observes the stereoscopic image Z1 through the half mirror 18.

The three-dimensional image virtual image Z1 may be inverted in the left-right direction so as to look at a normal mirror. Alternatively, the three-dimensional image virtual image Z1 may not be inverted in the left-right direction as seen by others. Such a method of determining the left-right direction can be supported by existing techniques such as left-right reversal of projectors 1R and 1L.

According to the image display device 102 of the present embodiment, by automatically following the position of the observer M and moving the observable range, the observer M always has his / her face without worrying about the observation position. Can be observed three-dimensionally.

In the present embodiment, the position of the observer M is acquired by using the position detection unit 16, but the position of the observer M may be detected from the images taken by the image pickup devices 19a and 19b. By doing so, since the position detection unit 16 becomes unnecessary, the cost of the image display device 101 can be reduced by reducing the number of parts.

The image display device 102 of the present embodiment can be used as a two-way communication means by installing another one in a remote place, for example. For example, the output signals of the image pickup devices 19a and 19b of the image display device 101 installed in the first place are transmitted as input signals to the projectors 1R and 1L of the image display device 101 installed in the second place, and the second The output signals of the image pickup devices 19a and 19b of the image display device 101 installed at the first location may be connected so as to be transmitted as input signals to the projectors 1R and 1L of the image display device 101 installed at the first location.

In this way, a three-dimensional bidirectional communication environment can be constructed. Even in this case, since the observable range moves following the observer M, the observer M can visually recognize the face of the other party at a remote location three-dimensionally without paying attention to the seating position. It is possible to perform two-way communication that is comfortable and has a sense of presence.

In the present embodiment, the positions of the screen 30 and the image pickup devices 19a and 19b with respect to the half mirror 18 may be interchanged.
In this case, the image light GR for the right eye and the image light GL for the left eye projected from the projectors 1R and 1L are reflected by the half mirror 18 and projected on the screen 30. The image light GR for the right eye and the image light GL for the left eye reflected by the screen 30 pass through the half mirror 18 and head toward the observer M. Further, the image pickup devices 19a and 19b will capture the image of the observer M reflected by the half mirror 18.
According to this configuration, since the surface of the screen 30 is arranged along the vertical direction, the holding structure of the screen 30 can be simplified as compared with the case where the screen 30 is held horizontally as shown in FIG.

The present invention is not limited to the contents of the above-described embodiment, and can be appropriately modified as long as the gist of the invention is not deviated.

For example, in the first embodiment, the case where the screen 10 is composed of one Fresnel lens 5 and the diffusion sheet 6 has been described as an example, but a configuration in which the diffusion sheet 6 is sandwiched between the two Fresnel lenses 5 is adopted. You may. In the case of this configuration, when two Fresnel lenses of the same lens are stacked, the focal length becomes about 1/2 of the focal length of the Fresnel lens alone (the configuration of the first embodiment).

Further, in the second embodiment, the case where the screen 10 is composed of one linear Fresnel lens 5A and the diffusion sheet 6 has been described as an example, but the configuration in which the diffusion sheet 6 is sandwiched between the two linear Fresnel lenses 5A. May be adopted.

Further, in the above embodiment, the case where the entire screen 10 is moved by the drive unit 11 has been described as an example, but the present invention is not limited to this, and the drive unit 11 is at least a Fresnel lens among the components of the screen 10. Any configuration may be used as long as only 5 is moved.

Further, in the above embodiment, the case where the screens 10, 20 and 30 are moved in the left-right direction or the up-down direction is taken as an example, but the screens 10, 20 are along the diagonal directions intersecting the left-right direction and the up-down direction. , 30 may be moved to move the observable range of the observer M. Further, when the observation position of the observer M moves in the front-rear direction, the observable range may be moved by moving the screens 10, 20, and 30 in the front-rear direction (thickness direction of the screen).

1L ... Projector (2nd projector), 1R ... Projector (1st projector), 5 ... Frenel lens (condensing part), 5A ... Linear Frenel lens (condensing part), 6 ... Diffusing sheet (diffusing part), 7 ... Reflective mirrors 10, 20, 30 ... Screen, 11 ... Drive unit, 12, 16 ... Position detection unit, 18 ... Half mirror, 19a, 19b ... Imaging device, 100, 101, 102 ... Image display device, EL ... Left eye , ER ... right eye, GL ... left eye image light (second image light), GR ... right eye image light (first image light), M ... observer.

Claims (6)

A screen including a condensing part and a light diffusing part arranged in the direction in which light passes, and
A first projector that emits first image light to the screen,
A second projector that emits second image light to the screen,
A detector that detects the position of the observer and
A stereoscopic image display device including a drive unit for moving at least the light collecting unit of the screen based on the detection result of the detection unit. The condensing unit is a Fresnel lens.
In the light diffusing portion, the light diffusing angle in the first direction of the screen is smaller than the light diffusing angle in the second direction intersecting with the first direction.
The stereoscopic image display device according to claim 1, wherein the driving unit moves at least the condensing unit in the first direction. The condensing unit is a linear Fresnel lens.
In the light diffusing portion, the light diffusing angle in the step direction of the linear Fresnel lens is smaller than the light diffusing angle in the direction intersecting the step direction.
The stereoscopic image display device according to claim 1, wherein the driving unit moves at least the condensing unit in the step direction. The condensing unit is a Fresnel lens.
The stereoscopic image display device according to claim 1, wherein the light diffusing characteristic of the light diffusing portion is isotropic. The stereoscopic image display device according to any one of claims 1 to 4, wherein the screen further includes a light collecting portion and a reflecting member that reflects light transmitted through the light diffusing portion. An image sensor that captures the observer and
A half mirror that transmits or reflects the first image light and the second image light emitted from the first projector and the second projector and causes them to enter the screen is further provided.
The first projector and the second projector project the first image light and the second image light corresponding to the image captured by the image sensor.
The stereoscopic image display device according to claim 5, wherein the half mirror reflects or transmits the first image light and the second image light reflected by the screen and guides the observer.

Images