JP2024011111A - display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device that can reduce degradation of a display element due to strong light incident from an eyepiece aperture when not in use, without increasing its size in an optical axis direction.

SOLUTION: A display device has a pair of optical systems, each of which guides an image from a display element to an observer and an eye-width adjustment mechanism for moving the pair of optical systems. The pair of optical systems are changeable between a first state in which an optically effective range of the pair of optical systems is not covered by a member different from the pair of optical systems when viewed from the optical axis direction of the pair of optical systems and a second state in which at least part of the optically effective range is covered by a member different from the pair of optical systems when viewed from the optical axis direction.

SELECTED DRAWING: Figure 5

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention mainly relates to a display device that is placed over the viewer's head or face and displays an image in front of the viewer's eyes.

In a head-mounted display (HMD), when not in use, strong light such as sunlight enters the eyepiece opening and is concentrated on the surface of the display element, which may cause the display element to burn and deteriorate. This phenomenon is also considered a problem in cameras equipped with electronic viewfinders, and countermeasures have been taken in the past. Patent Document 1 discloses a configuration in which an eyepiece is moved in the optical axis direction so that sunlight that enters the display element is not focused on the display element when the eyepiece is not in use.

Japanese Patent Application Publication No. 2003-153048

However, in the configuration of Patent Document 1, since the lens needs to be moved in the optical axis direction, the main body becomes larger in the optical axis direction.

An object of the present invention is to provide a display device that can reduce deterioration of a display element due to strong light incident from an eyepiece opening when not in use, without increasing the size in the optical axis direction.

A display device according to one aspect of the present invention includes a pair of optical systems, each of which guides an image from a display element to a viewer, and an interpupillary distance adjustment mechanism that moves the pair of optical systems. , the first state in which the effective optical range of the pair of optical systems is not covered by a member different from the pair of optical systems when viewed from the optical axis direction of the pair of optical systems, and the optical effective range when viewed from the optical axis direction is characterized in that it can change to a second state in which at least a portion of the pair of optical systems is covered with a member different from the pair of optical systems.

According to the present invention, it is possible to provide a display device that can reduce deterioration of a display element due to strong light incident from an eyepiece opening when not in use, without increasing the size in the optical axis direction.

FIG. 1 is a front perspective view of an image display device according to an embodiment of the present invention. FIG. 1 is a rear perspective view of an image display device according to an embodiment of the present invention. FIG. 3 is a rear view of the image display device. FIG. 3 is a sectional view taken along line AA in FIG. 2 of the image display device. FIG. 1 is a cross-sectional view of an image display device according to a first embodiment. FIG. 3 is a cross-sectional view of an image display device according to a second embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same reference numerals are given to the same members, and duplicate explanations will be omitted.

1 and 2 are a front perspective view and a back perspective view, respectively, of a head mounted display (hereinafter referred to as HMD) 100, which is an example of an image display device (display device) according to an embodiment of the present invention. The Z-axis direction is a direction parallel to the respective optical axes of the pair of eyepiece optical systems. The X-axis direction is a direction that connects the two optical axis centers of the pair of eyepiece optical systems. The Y-axis direction is a direction perpendicular to the X-axis direction and the Z-axis direction.

The HMD 100 is a video see-through head-mounted display that seamlessly fuses real space and virtual space in real time to provide mixed reality and augmented reality. The HMD 100 uses an image sensor to capture an external world image (optical image) that an observer observes through an imaging optical system, and displays a display image on the display element in which a computer graphics (CG) image is superimposed on the captured image. . An observer can observe the displayed image through the eyepiece optical system. When the optical axis of the eyepiece optical system and the optical axis of the imaging optical system are misaligned in the HMD 100, the viewer feels uncomfortable with the displayed image. When the HMD 100 increases in size in the optical axis direction, the viewer tends to feel uncomfortable with the displayed image or feel uncomfortable when wearing the HMD 100. In order to suppress misalignment between the optical axis of the eyepiece optical system and the optical axis of the imaging optical system, it is important to make the HMD 100 thinner. Furthermore, by making the HMD 100 thinner, it is possible to improve the usability when it is worn. The HMD 100 can be worn on the observer's head or placed over his or her face using a band-shaped or glasses-shaped attachment part.

The HMD 100 has a pair of eyepiece optical systems (a pair of optical systems) 10L and 10R corresponding to the left eye and right eye of an observer. The eyepiece optical systems 10L and 10R are covered with an exterior member 20. Images with parallax for the left eye and right eye are projected onto the eyepiece optical systems 10L and 10R, respectively, allowing the viewer to view a stereoscopic image. An operating member 30 operated by an observer is mounted on the upper surface of the HMD 100. The operating member 30 is used to turn on/off the device power, select items, change parameters, and the like. Two types of camera units, each with a different purpose, are mounted on the front of the HMD 100. Objective camera units 40L and 40R as imaging optical systems correspond to eyepiece optical systems 10L and 10R, respectively, and acquire images for the left eye and right eye. It is desirable that the objective camera units 40L and 40R are cameras that can take high-resolution color images. The position detection camera units 41L and 41R detect the position and orientation of the HMD 100 in real space. When using a CG image superimposed on images acquired by the objective camera units 40L and 40R, it is necessary to quickly switch the projected image in response to the movement of the observer's body. Therefore, it is desirable that the position detection camera unit 41 be a camera that can obtain images with a high frame rate and little distortion.

As shown in FIG. 2, the HMD 100 may include eyecups 50L and 50R that cover the side surfaces of the eyepiece optical systems 10L and 10R. The eyecups 50L, 50R are placed closer to the viewer than the eyepiece optical systems 10L, 10R, and the light incident from the side of the observer's face is reflected on the surface of the eyepiece optical systems 10L, 10R to allow viewing of images. Reduces inhibition. The HMD 100 is connected to an external communication device such as a PC and a battery via a communication cable 70, and is supplied with data and power regarding images to be projected on display panels (display elements) of the eyepiece optical systems 10L and 10R.

The HMD 100 includes an interpupillary distance adjustment mechanism (not shown) for adjusting the distance between the optical axes in the direction (X-axis direction) connecting the two optical axis centers of the eyepiece optical systems 10L and 10R in accordance with the interpupillary distance of the observer. ). 3(a) and 3(b) are rear views of the HMD 100 when the distance between the optical axes of the eyepiece optical systems 10L and 10R is minimized and maximized using the interpupillary distance adjustment mechanism, respectively, when the HMD 100 is used. It is. As shown in FIG. 3, the eyecups 50L, 50R move along the X-axis direction together with the eyepiece optical systems 10L, 10R.

Hereinafter, with reference to FIG. 4, the internal structures of the HMD 100 and the eyepiece optical systems 10L and 10R will be described. FIG. 4 is a cross-sectional view of the HMD 100 taken along line AA in FIG. In FIG. 4, the eyecups 50L, 50R, objective camera units 40L, 40R, and position detection camera units 41L, 41R are omitted.

The eyepiece optical systems 10L and 10R focus the image projected on the display panel 101 onto the observer's eyes 60 via the eyepiece lens 102 and the protective glass 105. The display panel 101, the eyepiece lens 102, and the protective glass 105 are held by a holding frame 104. The eyepiece optical systems 10L and 10R are connected to an interpupillary distance adjustment mechanism 106. The interpupillary distance adjustment mechanism 106 is used to move the eyepiece optical systems 10L, 10R in the left-right direction (X-axis direction) in the figure so that the eyepiece optical systems 10L, 10R are located in front of the observer's eyes 60L, 60R. used. The light ray 103 is a light ray that passes through the effective optical range of the eyepiece optical systems 10L and 10R until the image projected on the display panel 101 is focused on the observer's eye 60. Here, the optically effective range is the range through which light rays that contribute to image formation among the light rays that pass through the lens surface pass. Openings 201L and 201R corresponding to the eyepiece optical systems 10L and 10R are formed on the back side of the HMD 100 of the exterior member 20. The openings 201L and 201R are formed in a shape that does not block the light beam 103 when the HMD 100 is used.
(First embodiment)
With reference to FIG. 5, a method for reducing deterioration of the display panel 101 in the HMD 100 without an eyecup will be described. Figures 5(a) to 5(c) show that when the interpupillary distance adjustment mechanism minimizes the distance between the optical axes of the eyepiece optical systems 10R and 10L in the normally used area, and when it maximizes it, it expands to the non-used area. It is a sectional view of HMD100 in case.

As explained in FIG. 3, the HMD 100 can change the distance between the optical axes of the eyepiece optical systems 10L and 10R in the X-axis direction in accordance with the interpupillary distance of the observer. The area in which the eyepiece optical systems 10R and 10L can move between FIG. 5(a) and FIG. 5(b) is defined as a normal use area (first movement range) 210. The state of the eyepiece optical systems 10L and 10R when located within the normal use area 210 is defined as a first state. In the normal use area 210, the light beam 103 is focused on the observer's eye 60 without being interrupted. At this time, the observer can visually recognize the entire area of the image projected on the display panel 101.

The area where the eyepiece optical systems 10L and 10R can move between FIG. 5(b) and FIG. 5(c) is defined as a non-use area (second movement range) 220. The state of the eyepiece optical systems 10L and 10R when located within the non-use area 220 is defined as a second state. In the non-use area 220, a portion of the light ray 103 is blocked by light shielding parts 202R and 202L provided on the exterior member 20, which are members different from the eyepiece optical systems 10L and 10R. Thereby, when the HMD 100 is not in use, it is possible to prevent external light from being irradiated inside the eyepiece optical systems 10L, 10R. Therefore, the amount of light focused on the display panel 101 can be reduced, and deterioration of the display panel 101 can be reduced.

In this embodiment, the eyepiece optical system 10L has a first state in which the optically effective range of the eyepiece optical system 10L is not covered when viewed from the Z-axis direction, and a first state in which the optically effective range of the eyepiece optical system 10L is not covered when viewed from the Z-axis direction. and a second state in which at least a portion of the range is covered. Similarly, the eyepiece optical system 10R has two states: a first state in which the optically effective range of the eyepiece optical system 10R is not covered when viewed from the Z-axis direction, and a first state in which the optically effective range of the eyepiece optical system 10R is not covered when viewed from the Z-axis direction. and a second state in which at least a portion is covered. With such a configuration, it is possible to realize the HMD 100 that can reduce deterioration of the display panel 101 due to strong light incident from the eyepiece opening when not in use, without increasing the size in the optical axis direction.

Note that in the present embodiment, the eyepiece optical systems 10R and 10L move so as to widen the distance between the optical axes of the eyepiece optical systems 10R and 10L in the non-use area 220, but the present invention is not limited to this. As shown in FIG. 5(d), rotation around an arbitrary rotation axis parallel to the Y-axis direction (direction perpendicular to the Z-axis direction and the direction of movement of the eyepiece optical systems 10R and 10L in the normal use area 210) You may. Even in the case of FIG. 5(d), a portion of the light ray 103 is blocked by the light blocking portions 202R and 202L. Thereby, when the HMD 100 is not in use, it is possible to prevent external light from being irradiated inside the eyepiece optical systems 10L, 10R. Therefore, the amount of light focused on the display panel 101 can be reduced, and deterioration of the display panel 101 can be reduced.
(Second embodiment)
With reference to FIG. 6, a method for reducing deterioration of the display panel 101 in the HMD 100 having the eyecups 50L and 50R will be described. Figures 6(a) to 6(c) show that when the interpupillary distance adjustment mechanism minimizes the distance between the optical axes of the eyepiece optical systems 10R and 10L in the normally used area, and when it maximizes it, it expands to the non-used area. It is a sectional view of HMD100 in case.

The area in which the eyepiece optical systems 10R and 10L can move between FIG. 6(a) and FIG. 6(b) is defined as a normal use area 510 (first movement range). In the normal use area 510, the eyepiece optical system 10L and the eyecup 50L move as one. Similarly, the eyepiece optical system 10R and the eyecup 50R are driven as one. In the normal use area 510, the light beam 103 is focused on the observer's eye 60 without being interrupted. At this time, the observer can visually recognize the entire area of the image projected on the display panel 101.

The area in which the eyepiece optical systems 10R and 10L can move between FIG. 6(b) and FIG. 6(c) is defined as a non-use area (second movement range) 520. In the non-use area 520, the eyecups 50L and 50R are fixed to the exterior member 20 and are immovable. That is, only the eyepiece optical systems 10L and 10R move so as to widen the distance between the optical axes of the eyepiece optical systems 10R and 10L. In the non-use area 520, a portion of the light ray 103 is blocked by light shielding parts 502R and 502L provided on the eyecups 50L and 50R, respectively, which are members different from the eyepiece optical systems 10L and 10R. Thereby, when the HMD 100 is not in use, it is possible to prevent external light from being irradiated inside the eyepiece optical systems 10L, 10R. Therefore, the amount of light focused on the display panel 101 can be reduced, and deterioration of the display panel 101 can be reduced.

In this embodiment, the eyepiece optical system 10L has a first state in which the optically effective range of the eyepiece optical system 10L is not covered when viewed from the Z-axis direction, and a first state in which the optically effective range of the eyepiece optical system 10L is not covered when viewed from the Z-axis direction. and a second state in which at least a portion of the range is covered. Similarly, the eyepiece optical system 10R has two states: a first state in which the optically effective range of the eyepiece optical system 10R is not covered when viewed from the Z-axis direction, and a first state in which the optically effective range of the eyepiece optical system 10R is not covered when viewed from the Z-axis direction. and a second state in which at least a portion is covered. With such a configuration, it is possible to realize the HMD 100 that can reduce deterioration of the display panel 101 due to strong light incident from the eyepiece opening when not in use, without increasing the size in the optical axis direction.

In each embodiment, the interpupillary distance adjustment mechanism may be configured to be driven by the observer, or may be configured to be electrically driven using a driving device such as a motor. The drive device is controlled by a control board and is configured to switch the movement range of the eyepiece optical systems 10L and 10R between a normally used area and a non-used area in conjunction with the state of the HMD 100 (power ON/OFF, sleep mode, etc.). may be done. Further, if each eyepiece optical system is in the first state and the attitude of the HMD 100 is maintained in a state where the direction from the display panel 101 toward the viewer is vertically upward for a predetermined time or more, each eyepiece optical system is in the first state. It may be moved to the second state. Note that the direction from the display panel 101 toward the viewer does not necessarily have to be strictly vertically upward, as long as it is substantially vertically upward.

Further, by providing a locking mechanism between the normally used area and the non-used area, the movement range of the eyepiece optical systems 10L and 10R may be limited. For example, the locking mechanism is such that the eyepiece optical systems 10L and 10R change from the first state to the second state when the power is turned on, and the eyepiece optical systems 10L and 10R change from the second state to the first state when the power is turned off. may be restricted.

In addition, as examples of members that cover at least part of the effective optical range of the eyepiece optical system, the exterior member 20 and the eyecups 50L and 50R, which are members different from the eyepiece optical system, have been described. Any other member may be used as long as it is placed at a position on the side of .

The disclosure of this embodiment includes the following configurations.

(Configuration 1)
a pair of optical systems, each of which guides images from a display element to an observer;
and an interpupillary distance adjustment mechanism that moves the pair of optical systems,
The pair of optical systems has a first state in which the effective optical range of the pair of optical systems is not covered by a member different from the pair of optical systems when viewed from the optical axis direction of the pair of optical systems, and a first state in which the optical A display device characterized in that it can change to a second state in which at least a portion of the optically effective range is covered by a member different from the pair of optical systems when viewed from the axial direction.
(Configuration 2)
The display device according to configuration 1, wherein the pair of optical systems is movable between a first movement range in which the first state is set and a second movement range in which the second state is set.
(Configuration 3)
3. The display device according to configuration 1 or 2, wherein the pair of optical systems moves so that the distance between the optical axes of the pair of optical systems changes.
(Configuration 4)
In the first movement range, the pair of optical systems move such that the distance between the optical axes of the pair of optical systems changes, and in the second movement range, the distance between the optical axis direction and the first movement range is changed. The display device according to configuration 2, wherein the display device rotates around an axis parallel to a direction perpendicular to the movement direction.
(Configuration 5)
further comprising an exterior member that covers the optical system and the interpupillary distance adjustment mechanism,
5. The display device according to any one of configurations 1 to 4, wherein the exterior member covers at least a portion of the optically effective range when the pair of optical systems are in the second state.
(Configuration 6)
further comprising an eyecup located closer to the observer than the pair of optical systems,
5. The display device according to any one of configurations 1 to 4, wherein the eyecup covers at least a portion of the optically effective range when the pair of optical systems are in the second state.
(Configuration 7)
The eyecup moves together with the pair of optical systems when the pair of optical systems moves in the first state, and moves with the pair of optical systems when the pair of optical systems moves in the second state. The display device according to configuration 6, wherein the display device is immobile with respect to the display device.
(Configuration 8)
According to any one of configurations 1 to 7, the pair of optical systems moves to the first state or the second state depending on the state of the image display device. Display device.
(Configuration 9)
Configurations 1 to 1, characterized in that the pair of optical systems moves to the first state when the display device is powered on, and moves to the second state when the display device is powered off. 9. The display device according to any one of 9.
(Configuration 10)
When the pair of optical systems are in the first state and the attitude of the display device is maintained for a predetermined time or longer in a state where the direction from the display element side to the viewer side is vertically upward, the 10. The display device according to any one of configurations 1 to 9, wherein the pair of optical systems moves so as to be in the second state.
(Configuration 11)
The pair of optical systems change from the first state to the second state when the display device is powered on, and the pair of optical systems change from the second state to the first state when the display device is powered off. 11. The display device according to any one of configurations 1 to 10, further comprising a locking mechanism that restricts the display device from changing.
(Configuration 12)
The display device according to any one of configurations 1 to 11, characterized in that it can be mounted on the head of an observer.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the invention.

100 Image display device (display device)
10L, 10R Eyepiece optical system (optical system)
101 Display panel (display element)
106 Interpupillary distance adjustment mechanism

Claims (12)

a pair of optical systems, each of which guides images from a display element to an observer;
and an interpupillary distance adjustment mechanism that moves the pair of optical systems,
The pair of optical systems has a first state in which the effective optical range of the pair of optical systems is not covered by a member different from the pair of optical systems when viewed from the optical axis direction of the pair of optical systems, and a first state in which the optical A display device characterized in that it can change to a second state in which at least a portion of the optically effective range is covered by a member different from the pair of optical systems when viewed from the axial direction. 2. The display device according to claim 1, wherein the pair of optical systems are movable between a first movement range in which the first state is achieved and a second movement range in which the second state is achieved. 3. The display device according to claim 1, wherein the pair of optical systems move so that the distance between the optical axes of the pair of optical systems changes. In the first movement range, the pair of optical systems move such that the distance between the optical axes of the pair of optical systems changes, and in the second movement range, the distance between the optical axis direction and the first movement range is changed. The display device according to claim 2, wherein the display device rotates around an axis parallel to a direction perpendicular to the direction of movement. further comprising an exterior member that covers the optical system and the interpupillary distance adjustment mechanism,
3. The display device according to claim 1, wherein the exterior member covers at least a portion of the optically effective range when the pair of optical systems are in the second state. further comprising an eyecup located closer to the observer than the pair of optical systems,
3. The display device according to claim 1, wherein the eyecup covers at least a portion of the optically effective range when the pair of optical systems are in the second state. The eye cup is characterized in that it moves together with the pair of optical systems when the pair of optical systems moves in the first state, and remains stationary when the pair of optical systems moves in the second state. The display device according to claim 6. 3. The display device according to claim 1, wherein the pair of optical systems moves to the first state or the second state depending on the state of the display device. 2. The pair of optical systems move to the first state when the display device is powered on, and move to the second state when the display device is powered off. Or the display device according to 2. When the pair of optical systems are in the first state and the attitude of the display device is maintained for a predetermined time or longer in a state where the direction from the display element side to the viewer side is vertically upward, the 3. The display device according to claim 1, wherein the pair of optical systems moves to the second state. The pair of optical systems change from the first state to the second state when the display device is powered on, and the pair of optical systems change from the second state to the first state when the display device is powered off. 3. The display device according to claim 1, further comprising a locking mechanism that restricts the display device from changing. The display device according to claim 1 or 2, wherein the display device can be mounted on the head of an observer.