Video display device

Abstract

To provide a video display device with reduced thickness and size in a direction perpendicular to an optical axis.SOLUTION: A video display device is provided, comprising displays for displaying images to a user, ocular optical systems for guiding the images displayed on the displays to the user, and guiding mechanisms for moving the displays in an optical axis direction of the ocular optical systems. The guiding mechanisms are located on both sides of the displays in a direction perpendicular to the optical axis of the ocular optical systems so as to overlap the ocular optical systems when viewed from the optical axis direction.SELECTED DRAWING: Figure 2

Description

Technical Field

[0002] ,

[0001] The present invention relates to a video display device provided with a mechanism for adjusting visibility.

Background Art

[0002] Conventionally, a video display device provided with a mechanism for adjusting visibility by moving either the display or the eyepiece optical system in the direction of the optical axis of the eyepiece optical system according to the visibility of the user or the subject distance of the displayed image has been proposed (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003] [[ID=2)]]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a conventional video display device, when a bending optical system or the like is used to reduce the thickness, the size in the direction orthogonal to the optical axis of the eyepiece optical system may increase. In this case, in the conventional video display device, since a part of the mechanism for adjusting visibility is arranged at a position farther from the optical axis than the eyepiece optical system, the size in the direction orthogonal to the optical axis of the video display device also increases.

[0005] An object of the present invention is to provide a video display device that achieves both thinning and downsizing in the direction orthogonal to the optical axis.

Means for Solving the Problems

[0006] One aspect of the present invention is an image display device comprising a display unit that displays an image to the user, an eyepiece optical system that guides the image displayed on the display unit to the user, and a guide mechanism that moves the display unit in the direction of the optical axis of the eyepiece optical system, wherein the guide mechanism is arranged on both sides of the display unit in a direction perpendicular to the optical axis of the eyepiece optical system, and is arranged so as to overlap with the eyepiece optical system when viewed from the direction of the optical axis. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an image display device that achieves both thinning and miniaturization in the direction perpendicular to the optical axis. [Brief explanation of the drawing]

[0008] [Figure 1] This is an external view of a head-mounted display, which is an example of an image display device according to an embodiment of the present invention. [Figure 2] This is a diagram showing the configuration of a head-mounted display according to the first embodiment. [Figure 3] This diagram illustrates the positional relationship between the guide mechanism and the imaging unit in the first embodiment. [Figure 4] This is a diagram illustrating the arrangement of the drive unit in the first embodiment. [Figure 5] This diagram illustrates the arrangement of the drive unit in the comparative example. [Figure 6] This is a diagram showing the configuration of a head-mounted display according to a second embodiment. [Figure 7] This is a diagram illustrating the configuration of a head-mounted display according to the third embodiment. [Figure 8] This is a diagram illustrating the configuration of a head-mounted display according to the fourth embodiment. [Figure 9] This diagram illustrates a case where the configuration of the guidance mechanism in the comparative example is different. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described in detail below with reference to the drawings. In each drawing, the same reference numeral is used for identical components, and redundant descriptions are omitted.

[0010] Figure 1 is an external view of a head-mounted display (hereinafter referred to as HMD) 30, which is an example of an image display device according to an embodiment of the present invention. In the following description, the direction parallel to the optical axis of the eyepiece optical system mounted on the HMD 30 (optical axis direction) is defined as the Z-axis direction, the direction in which the user's (observer's) right eye 10R and left eye 10L are aligned (direction of binocular alignment) is defined as the X-axis direction, and the direction perpendicular to the X-axis direction and the Z-axis direction is defined as the Y-axis direction. In the X-axis direction, the direction from the left eye 10L side toward the right eye 10R side is defined as the +X direction, and the direction from the right eye 10R side toward the left eye 10L side is defined as the -X direction. In the Y-axis direction, the direction from the user's chin side toward the user's head crown side is defined as the +Y direction, and the direction from the head crown side toward the chin side is defined as the -Y direction. In the Z-axis direction, the direction from the user's eye side toward the display unit mounted on the HMD 30 that displays images to the user is defined as the +Z direction, and the direction from the display unit side toward the user's eye side is defined as the -Z direction.

[0011] The HMD30 has a belt portion 30a for attachment to the user's head 10. The HMD30 also has a structure for the left eye 10L and a structure for the right eye 10R. The structures for the left eye 10L and the right eye 10R are approximately symmetrical with respect to the Z-axis. The user can observe the displayed image from the HMD30 with both the right eye 10R and the left eye 10L.

[0012] In the following explanation, components included in the structure for the left eye (10L) are denoted by L, and components included in the structure for the right eye (10R) are denoted by R. For example, with respect to display unit 1 described later, the display unit included in the structure for the left eye (10L) is denoted by 1L, and the display unit included in the structure for the right eye (10R) is denoted by 1R. Note that if there is no distinction between the structure for the left eye and the structure for the right eye, L and R will be omitted in the explanation. [First Embodiment] Figure 2 is a diagram of the HMD30 in this embodiment. Figure 2(a) is a schematic diagram of the HMD30 as viewed from the +Y direction. Figure 2(b) is a schematic diagram of the HMD30 as viewed from the -Z direction. In this embodiment, the structure 9L for the left eye 10L will be mainly described, but the structure 9R for the right eye 10R is similar.

[0013] Structure 9L comprises an image display unit 3L, a holding member 4L, shaft members 5L, 6L, a drive unit 7L, and an imaging unit 8L. The image display unit 3L includes a display unit 1L and an eyepiece optical system 2L. The holding member 4L includes a first guide part 4La and a second guide part 4Lb, and is provided on a movable part (not shown) that is movable in the Z-axis direction. The first guide part 4La consists of two fitting holes in the Z-axis direction, which is parallel to the optical axis 2La of the eyepiece optical system 2L. The shaft member 5L is provided on a fixed part (not shown) that is fixed in the Z-axis direction and engages with the two fitting holes of the first guide part 4La. The Z-axis positional relationship between the first guide part 4La and the shaft member 5L is changeable. The second guide part 4Lb consists of one fitting hole in the Z-axis direction. The shaft member 6L is provided on the fixed part and engages with the one fitting hole of the second guide part 4Lb. The Z-axis positional relationship between the second guide portion 4Lb and the shaft member 6L is changeable. The play between the shaft member 5L and the two fitting holes of the first guide portion 4La, and the play between the shaft member 6L and the one fitting hole of the second guide portion 4Lb, is reduced by a play-reducing mechanism such as a spring (not shown). As a result, the holding member 4L and the shaft members 5L and 6L are positioned in a stable orientation. The first guide portion 4La, the second guide portion 4Lb, and the shaft members 5L and 6L constitute a guide mechanism for moving the display unit 1L in the Z-axis direction. Note that the first guide portion 4La and the shaft member 5L may be fitted at multiple locations, and the second guide portion 4Lb and the shaft member 6L may be fitted at fewer locations; the number of fitting locations is not limited.

[0014] In this embodiment, the first guide part 4La is arranged outside the structures 9L and 9R in the X-axis direction (the side where one of the displays 1L and 1R is arranged with respect to the other). Also, the second guide part 4Lb is arranged inside the structures 9L and 9R in the X-axis direction (the side opposite to the side where one of the displays 1L and 1R is arranged with respect to the other). Specifically, the first guide part 4La is arranged on the -X direction side with respect to the display 1L (the side opposite to the side where the display 1R is arranged), and the second guide part 4Lb is arranged on the +X direction side with respect to the display 1L. Also, the first guide part 4Ra provided on the holding member 4R is arranged on the +X direction side with respect to the display 1R (the side opposite to the side where the display 1L is arranged), and the second guide part 4Rb provided on the holding member 4R is arranged on the -X direction side with respect to the display 1R.

[0015] In this embodiment, the holding member 4L includes the first guide part 4La and the second guide part 4Lb, but may also include the shaft members 5 and 6. In this case, the first guide part 4La and the second guide part 4Lb are provided on the fixing part.

[0016] The drive part 7L is an actuator such as an ultrasonic motor or a voice coil motor, for example, and is connected to the holding member 4L and drives the guide mechanism to move the display 1L in the Z-axis direction. The guide mechanism and the drive part 7L constitute the diopter adjustment part.

[0017] The display light beam of the video displayed on the display 1L passes through the eyepiece optical system 2L and reaches the left eye 10L. The diopter adjustment part performs diopter adjustment by moving the display 1L in the Z-axis direction to change the optical positional relationship between the display 1L and the eyepiece optical system 2L. For example, when changing the diopter of the video display part 3L in the infinite distance direction, the display 1L is moved in the +Z direction, and when changing it in the nearest direction, the display 1L may be moved in the -Z direction.

[0018] In this embodiment, the video display units 3L and 3R each include a diopter adjustment unit. Therefore, it is possible to perform diopter adjustment with the structures 9L and 9R, and it is possible to perform appropriate diopter adjustment even for a user with a difference in visual acuity between the left and right eyes.

[0019] The imaging unit 8L includes an imaging sensor and an imaging optical system, and is disposed on the +Z direction side of the display 1L. The imaging unit 8L captures images on the +Z direction side, and the acquired images can be displayed on the display 1L.

[0020] The structures 9L and 9R are guided in the X-axis direction by an interpupillary distance adjustment unit (not shown) provided in each of them. With such a configuration, it is possible to perform an interpupillary distance adjustment for adjusting the distance between the structures 9L and 9R in accordance with the interpupillary distance corresponding to the distance between the left eye 10L and the right eye 10R. The interpupillary distance may be acquired by a detection unit (not shown) or may be acquired by a manual operation based on the user's input.

[0021] In this embodiment, the ocular optical system 2 uses one that is large in size in the X-axis direction and the Y-axis direction. Thereby, for example, by using an optical system that utilizes polarization and reflection, the dimension in the Z-axis direction can be suppressed to be small, and the HMD 30 can be made thinner.

[0022] In this embodiment, as shown in FIG. 2(b), when viewed from the -Z direction side (the side of the user's eyes), the guiding mechanism is disposed so as to overlap with the ocular optical system 2 (within the projection of the ocular optical system 2). Thereby, it is possible to avoid disposing the guiding mechanism on the side away from the optical axis 2a (the side surface of the ocular optical system) of the ocular optical system 2 in the direction orthogonal to the optical axis (the X-axis direction or the Y-axis direction), and thus it is possible to suppress the increase in size of the HMD 30 in the direction orthogonal to the optical axis. <000,0109> Figure 3 shows the positional relationship between the guide mechanism and the imaging unit 8L. The position range D1 of the guide mechanism in the Z-axis direction and the position range D2 of the imaging unit 8L in the Z-axis direction overlap in the Z-axis direction, but do not overlap in the X-axis direction. In other words, in this embodiment, the size in the Z-axis direction is reduced by utilizing the space in the X-axis direction.

[0024] As shown in Figure 2(b), the guide mechanism is positioned on both sides of the display unit 1 in the X-axis direction, flanking the display unit 1. Furthermore, as shown in Figure 2(b), the guide mechanism is positioned in the Y-axis direction on the +Y side with respect to the optical axis 2a of the eyepiece optical system 2. This suppresses the generation of tilting moments with the first guide section 4a, the second guide section 4b, and the two axial members 5 and 6 as pivot points, thereby suppressing twisting between the guide sections and the axial members. Alternatively, the guide mechanism may be positioned in the Y-axis direction on the -Y side with respect to the optical axis 2a of the eyepiece optical system 2.

[0025] Figure 4 is a diagram illustrating the arrangement of the drive unit 7. Figure 4(a) shows the HMD 30 when the distance between the image display units 3L and 3R, which corresponds to the interpupillary distance, is W1. Figure 4(b) shows the HMD 30 when the distance between the image display units 3L and 3R is the shortest, W2. The drive unit 7 includes a connecting part 7a that is connected to the holding member 4. The drive unit 7 and the holding member 4 are connected in the X-axis direction on the side where the first guide part 4a and the shaft member 5 are located. This makes it possible to avoid interference between the drive units 7L and 7R even when the interpupillary distance is adjusted so that the distance between the image display units 3L and 3R is as close as possible (to the state shown in Figure 4(b)). If the drive unit 7 and the holding member 4 are connected in the X-axis direction on the side where the second guide part 4b and the shaft member 6 are located, as shown in Figure 5, then the drive units 7L and 7R will interfere with each other when the interpupillary distance is adjusted from the state shown in Figure 5(a) to the state shown in Figure 5(b). Furthermore, since the first guide portion 4a consists of two fitting holes in the Z-axis direction, by bringing the point where the driving force from the drive unit 7 is transmitted closer to the first guide portion 4a, twisting between the first guide portion 4 and the shaft member 5 when the driving force is transmitted can be suppressed.

[0026] As described above, the configuration of this embodiment makes it possible to realize an image display device that achieves both thinning and miniaturization in the direction perpendicular to the optical axis. [Second Embodiment] Figure 6 is a diagram showing the configuration of the HMD30 in this embodiment. In this embodiment, everything is the same as in the first embodiment except for the shape of the retaining member 4. In this embodiment, only the parts that differ from the first embodiment will be described.

[0027] The retaining members 4L and 4R have different shapes. The second guide portions 4Lb and 4Rb are provided at different positions in the Z-axis direction. Specifically, the second guide portion 4Lb is provided on the +Z side of the second guide portion 4Rb. Also, the shaft member 6L that fits into the second guide portion 4Lb is provided on the +Z side of the shaft member 6R that fits into the second guide portion 4Rb. Since the second guide portion 4Lb consists of one fitting hole in the Z-axis direction, the size of the second guide portion 4Lb in the Z-axis direction can be made smaller than that of the first guide portion 4La. Similarly, the size of the shaft member 6 in the Z-axis direction can be made smaller than that of the shaft member 5. Therefore, even when the interpupillary distance is adjusted so that the distance between the image display units 3L and 3R is as close as possible, the configuration including the second guide portion 4Lb and shaft member 6L does not interfere with each other. This configuration makes it possible to suppress an increase in the size of the HMD30 in the X-axis direction.

[0028] It should be noted that the effects of this embodiment are obtained when, when viewed from the -Z direction, at least a part of the peripheral structure of the second guide portion 4b is positioned outside the projection of the eyepiece optical system 2 due to reasons such as rigidity. Since the second guide portion 4b and the shaft member 6 are positioned to overlap with the eyepiece optical system 2, these members in the structure of the left and right eyes are configured not to interfere with other members in the first place.

[0029] As described above, the configuration of this embodiment makes it possible to realize an image display device that achieves both thinning and miniaturization in the direction perpendicular to the optical axis. [Third Embodiment] Figure 7 is a diagram showing the configuration of the HMD30 in this embodiment. In this embodiment, everything is the same as in the first embodiment except for the shape of the retaining member 4. In this embodiment, only the parts that differ from the first embodiment will be described.

[0030] The retaining members 4L and 4R have different shapes. The second guide portions 4Lb and 4Rb are located at different positions in the Y-axis direction. Specifically, the second guide portion 4Lb is located on the +Y side of the second guide portion 4Rb. Therefore, even when the interpupillary distance is adjusted so that the distance between the image display units 3L and 3R is minimized, the configuration including the second guide portion 4Lb and axis member 6L does not interfere with each other. This makes it possible to suppress an increase in the size of the HMD 30 in the X-axis direction.

[0031] Since the second guide portion 4Rb and the shaft member 6R are positioned on the -Y direction side with respect to the optical axis 2Ra of the eyepiece optical system 2, in this embodiment, a tilting moment occurs with the first guide portion 4a, the second guide portion 4b, and the shaft members 5 and 6 as pivot points. However, since the shape of the retaining member 4R is the same as the retaining member 4L rotated 180 degrees around the optical axis 2La, it becomes possible to assemble a configuration in which identical parts are reversed. This eliminates the need to create parts of different shapes for the left and right eye structures.

[0032] As described above, the configuration of this embodiment makes it possible to realize an image display device that achieves both thinning and miniaturization in the direction perpendicular to the optical axis. [Fourth Embodiment] Figure 8 is a diagram showing the configuration of the HMD30 in this embodiment. In this embodiment, it is the same as the first embodiment except for the arrangement of the imaging unit 8. In this embodiment, only the parts that differ from the first embodiment will be described.

[0033] In the HMD30, the user's line of sight may be tilted relative to the optical axis 2a of the eyepiece optical system 2. For example, in order to allow the user to observe the object displayed on the display unit 1 at an angle, as if the user were viewing an object in real space, the line of sight 10La of the left eye 10L and the line of sight 10Ra of the right eye 10R may be tilted inward with respect to the optical axes 2La and 2Ra, as shown in Figure 8. In this case, in order to acquire the optimal image, the imaging units 8L and 8R should be positioned so that their imaging directions 8La and 8Ra are inward, in line with the lines of sight 10La and 10Ra. In this embodiment, the HMD30 is configured to have a line of sight detection unit (not shown) consisting of a light-emitting element and a camera that detect the lines of sight 10La and 10Ra, and an angle changing unit (not shown) consisting of a guide mechanism and actuators that change the angle of the imaging units 8L and 8R, thereby allowing the imaging direction to be varied.

[0034] The second guide portion 4Lb and the shaft member 6L are positioned on the +X side of the video display unit 3L, and the second guide portion 4Rb and the shaft member 6R are positioned on the -X side of the video display unit 3R. In this embodiment, even if the shooting directions 8La and 8Ra are tilted inward (towards the second guide portion 4b with respect to the Z-axis direction), the second guide portion 4L and the shaft member 6 do not obstruct the shooting angles 8Lb and 8Rb of the shooting units 8L and 8R, as shown in Figure 8. The case in which the first guide portion 4La and the shaft member 5 are positioned on the +X side of the video display unit 3L, and the first guide portion 4Ra and the shaft member 5R are positioned on the -X side of the video display unit 3R, as shown in Figure 9, will be described. In this case, if the shooting directions 8La and 8Ra are tilted inward, the ranges AL and AR of the shooting angles 8Lb and 8Rb will be obstructed.

[0035] As described above, the configuration of this embodiment makes it possible to realize an image display device that achieves both thinning and miniaturization in the direction perpendicular to the optical axis.

[0036] 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 are possible within the scope of its gist. [Explanation of Symbols]

[0037] 1 Display 2 Eyepiece optical system 2a optical axis 4a First Information Section 4b Second Information Section 5 Shaft member 6 Shaft member 30. Head-mounted display (image display device)

Claims

1. a display for displaying an image to a user; an eyepiece optical system for guiding the image displayed on the display to the user; a guide mechanism for moving the display in the optical axis direction of the eyepiece optical system, The image display device according to claim 1, wherein the guide mechanism is disposed so as to overlap the eyepiece optical system when viewed from the optical axis direction.

2. An image display device as described in Claim 1, characterized in that the guide mechanism is arranged on both sides of the display in a direction perpendicular to the optical axis perpendicular to the optical axis of the eyepiece optical system.

3. the display includes a first display for displaying an image for the left eye and a second display for displaying an image for the right eye; the eyepiece optical system includes a first eyepiece optical system that guides the image displayed on the first display to the left eye of the user, and a second eyepiece optical system that guides the image displayed on the second display to the right eye of the user, the guide mechanism includes a first guide mechanism that moves the first indicator in the optical axis direction and a second guide mechanism that moves the second indicator in the optical axis direction, the first guide mechanisms are disposed on both sides of the first display in an arrangement direction of the first display and the second display, and are disposed so as to overlap with the first eyepiece optical system when viewed from the optical axis direction, The image display device according to claim 2, characterized in that the second guide mechanism is arranged on both sides of the second display in the arrangement direction and is arranged so as to overlap with the second eyepiece optical system when viewed from the optical axis direction.

4. The guide mechanism further includes a drive unit that drives the guide mechanism, The image display device according to claim 3, characterized in that the drive unit is connected to the guide mechanism on the side opposite to the side on which the other of the first display unit and the second display unit is arranged, relative to one of the first display unit and the second display unit in the arrangement direction.

5. each of the first guide mechanism and the second guide mechanism includes a first shaft member, a second shaft member, a first guide portion that is engaged with the first shaft member at a plurality of locations, and a second guide portion that is engaged with the second shaft member at fewer locations than the first guide portion that is engaged with the first shaft member; a positional relationship between the first guide portion and the first shaft member in the optical axis direction and a positional relationship between the second guide portion and the second shaft member in the optical axis direction are changeable, the first guide portion is disposed on an opposite side of one of the first display device and the second display device from a side on which the other of the first display device and the second display device is disposed in the arrangement direction, The image display device according to claim 3 or 4, characterized in that the second guide portion is arranged on the side of one of the first display and the second display on which the other of the first display and the second display is arranged in the arrangement direction.

6. The imaging unit further includes an imaging unit that has a variable imaging direction and acquires an image to be displayed on the display device, 6. The image display device according to claim 5, wherein when the shooting direction is inclined toward the second guide portion with respect to the optical axis direction, the second guide portion does not block the angle of view of the shooting portion.

7. 7. The image display device according to claim 3, wherein the first guide mechanism and the second guide mechanism are arranged on only one side of the optical axis in a direction perpendicular to the optical axis direction and the arrangement direction.

8. 7. The image display device according to claim 5, wherein the positions of the second guide portion provided on the first guide mechanism and the second guide portion provided on the second guide mechanism in the optical axis direction are different from each other.

9. The image display device according to claim 5 or 6, characterized in that the positions of the second guide portion provided in the first guide mechanism and the second guide portion provided in the second guide mechanism in a direction perpendicular to the optical axis direction and the arrangement direction are different from each other.

10. an adjustment unit that changes a distance between the first display unit and the second display unit in the arrangement direction, The image display device according to claim 8 or 9, characterized in that when the adjustment unit changes the gap to be the shortest, a configuration including the second guide portion provided on the first guide mechanism and a configuration including the second guide portion provided on the second guide mechanism do not interfere with each other.

11. Further, a photographing unit is provided for acquiring an image to be displayed on the display device, 6. The image display device according to claim 1, wherein the guide mechanism is disposed so as to overlap the image capturing unit in the optical axis direction.

Images