Video display device

Abstract

To provide a video display device that can prevent a reduction of immersive feel due to a drive sound generated when a part of a mechanism for showing a 3D video to a user is moved by using a motor.SOLUTION: A video display device can be used when worn on the head of a user, and has: a first optical unit that outputs one of a video for the left eye and a video for the right eye; a second optical unit that outputs the other of the video for the left eye and the video for the right eye; and a motor that has a vibrator that vibrates upon application of voltage and a contact member that is brought into contact with a projection provided on the vibrator, and in which the vibrator vibrates to generate a driving force for moving an optical member included in the first optical unit. When seen from an optical axis direction of the optical member, the motor is arranged on the opposite side of the side where the second optical unit is arranged with respect to an optical axis of the optical member, and the contact member is arranged at a position more distant from the optical member than the vibrator.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an image display device that can be worn on a user's head. [Background technology]

[0002] Head-mounted displays (HMDs), which can be worn on a user's head, provide images to the user using an optical system equipped with optical components such as a display and lenses. Recently, many of these display devices provide three-dimensional (3D) images by displaying images rendered with binocular parallax on a display unit for the left and right eyes. 3D imaging techniques that utilize binocular parallax can place a strain on the user due to a convergence-accommodation conflict caused by a mismatch between the convergence and accommodation distances of the two eyes. To solve this problem, variable-focus mechanisms that change the accommodation distance (or focal length) of optical systems equipped with displays and lenses are being investigated.

[0003] Patent Document 1 discloses a virtual reality (VR) headset in which an actuator drives any of the optical members included in an optical system that includes a display, a lens, and the like as a variable focus mechanism. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6502586 Summary of the Invention [Problem to be solved by the invention]

[0005] However, Patent Document 1 does not take into consideration the problem that when a VR headset is worn on a user's head, the driving noise of the actuator may be heard by the user, which may impair the sense of immersion in the video content.

[0006] Therefore, an object of the present invention is to provide an image display device that can suppress a decrease in the sense of immersion caused by the driving noise when part of the mechanism for showing 3D images to the user is moved by a motor. [Means for solving the problem]

[0007] In order to achieve the above object, the image display device of the present invention is an image display device that can be worn on a user's head and used, and has a first optical unit that outputs one of an image for the left eye and an image for the right eye, a second optical unit that outputs the other of the image for the left eye and the image for the right eye, a vibrator that vibrates when a voltage is applied and a contact member that comes into contact with a protrusion provided on the vibrator, and a motor that generates a driving force that moves an optical element included in the first optical unit when the vibrator vibrates, and is characterized in that, when viewed from the optical axis direction of the optical element, the motor is positioned on the opposite side of the optical axis of the optical element from the side on which the second optical unit is positioned, and the contact member is positioned farther from the optical element than the vibrator. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an image display device that can suppress a decrease in the sense of immersion caused by drive noise when a part of a mechanism for showing 3D images to a user is moved by a motor. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram illustrating a configuration of an image display device that can be worn on a user's head according to an embodiment of the present invention. [Figure 2] FIG. 1 is a diagram illustrating the configuration of a variable focus mechanism according to a first embodiment of the present invention. [Figure 3] FIG. 1 is a diagram illustrating the configuration of an actuator used in a variable-focus mechanism according to a first embodiment of the present invention. [Figure 4] FIG. 10 is a diagram showing the influence of the driving noise of an actuator included in a video display device. [Figure 5]FIG. 10 is a diagram showing the influence of driving noise of an actuator included in the image display device according to the first embodiment. [Figure 6] FIG. 10 is a diagram showing the influence of the driving noise of an actuator included in a video display device. [Figure 7] FIG. 10 is a diagram illustrating the configuration of a variable focus mechanism according to a second embodiment of the present invention. [Figure 8] FIG. 10 is a diagram showing the influence of the driving sound of an actuator included in the image display device according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments of the present invention will now be described.

[0011] (First embodiment) First, a head-mounted display (HMD1) according to a first embodiment will be described, which is an image display device that can be worn on a user's head and used. FIG. 1 is a diagram showing the configuration of the HMD 1, and FIG. 1(a) is a perspective view of the HMD 1. The HMD 1 is composed of an HMD main body 11 and a wearing unit 12. The wearing unit 12 is a band-like member that can be worn on the user's head, and the HMD main body 11 is held by the wearing unit 12 and placed in front of the user's eyes when the wearing unit 12 is worn on the user's head. The wearing unit 12 also has a speaker 120 that is placed in a position near the user's ear when the wearing unit 12 is worn on the user's head. The output method of the speaker 120 is not particularly limited and may be air conduction or bone conduction. The speaker 120 outputs sound corresponding to the image content displayed on the HMD main body 11. The speaker 120 may be provided in the HMD main body 11. 1, the Z direction corresponds to the direction in which the user views the image when using the HMD 1, the X direction corresponds to the left-right direction of the image viewed by the user, and the Y direction corresponds to the up-down direction of the image viewed by the user. The HMD 1 of this embodiment is configured as a band-like member worn on the user's head, but it may also be a glasses-shaped image display device.

[0012] FIG. 1(b) is a view of the HMD main body 11 as viewed from the side facing the user when worn. The HMD main body 11 has two optical units 13, 13' that display images to the user's left and right eyes. A display 141 and a movable lens 142, which will be described later, are disposed in the optical units 13, 13' as optical components, and a virtual image of the display 141 can be seen by observing the display 141 through the movable lens 142. In this way, the user can observe 3D images through the optical units 13, 13'. The HMD main body 11 also has various circuits for overall control, such as a display control circuit that controls the image displayed on the display 141 and a drive control circuit that controls an actuator that moves the movable lens 142. The various circuits are configured by a computing device such as at least one CPU (Central Processing Unit), and various controls are performed by the CPU executing control programs stored in internal memory.

[0013] In addition, in FIG. 1(b), the XZ plane passing through the optical axis O1 of the optical unit described later and the optical axis O1' of the optical unit 13' is the horizontal plane P1, and the YZ plane that is perpendicular to the horizontal plane P1 and is equidistant from the two optical axes O1 and O1' is the central plane P2.

[0014] Next, the variable focus mechanism of the HMD 1 will be described with reference to Figure 2. Figure 2 is a diagram showing the configuration of the variable focus mechanism, and Figure 2(a) is an exploded perspective view of the left eye optical unit 13. The configuration of the left eye optical unit 13 will be described below, but the left eye optical unit 13 and the right eye optical unit 13' are mirror symmetrical in the X direction with respect to the central plane P2. In other words, if the X direction and the -X direction of the left eye optical unit 13 are interchanged, it becomes the right eye optical unit 13', so a description of the configuration of the right eye optical unit 13' will be omitted.

[0015] The left-eye optical unit 13 is mainly composed of a display 141, which is a display unit, a movable lens 142, a lens holder 131, a guide bar 132, a vibration motor 15, a front cover 133, a first exterior 134, and a second exterior 135. In the left-eye optical unit 13, the optical axis of the optical system composed of the display 141 and the movable lens 142, which are optical members, is denoted as O1. That is, the optical axis O1 corresponds to the optical axis of the display 141 and the optical axis of the movable lens 142 of the left-eye optical unit 13. A similar optical axis is defined for the right-eye optical unit 13' and is denoted as O1'. In this embodiment, the optical axes O1 and O1' are described as being parallel to the Z direction. As described above, the left-eye optical unit 13 displays an image for the left eye on the display 141 and guides the image displayed on the display 141 to the user using the movable lens 142, thereby outputting the image for the left eye. Similarly, the right-eye optical unit 13' displays an image for the right eye on a display 141 and outputs the image for the right eye by guiding the image displayed on the display 141 to the user using a movable lens 142.

[0016] The display 141 of the left eye optical unit 13 is fixed to the first exterior 134. The movable lens 142 is fixed to the lens holder 131, and the lens holder 131 is held by two guide bars 132 so as to be movable in the driving direction D1 of the vibration type motor 15. The driving direction D1 is approximately parallel to the optical axis O1. The vibration type motor 15 drives the movable lens 142 together with the lens holder 131 in the driving direction D1. The front cover 133 is fixed to the first exterior 134, and the front cover 133 and the first exterior 134 support the two guide bars 132.

[0017] When viewed from the optical axis O1 direction (Z direction), the first exterior 134 and the second exterior 135 are arranged so as to surround almost the entire periphery of the optical members, ie, the display 141 and the movable lens 142. In other words, when viewed from the optical axis O1 direction (Z direction), the display 141 and the movable lens 142, which are optical members, are arranged within an area surrounded by the cover members constituted by the first exterior 134, which is the first cover member, and the second exterior 135, which is the second cover member.

[0018] The first exterior 134 has a through-hole 134a that penetrates in the X direction. The vibration motor 15 is fixed to the first exterior 134 at a position farther from the optical axis O1 in the X direction than the opening 134a, and a part of the vibration motor 15 is connected to the lens holder 131 via the opening 134a. The second exterior 135 is disposed at a position that closes the opening 134a in the X direction, and covers the vibration motor 15 on the side opposite to the optical axis O1 side of the vibration motor 15.

[0019] 2(b) and 2(c) are detailed diagrams of the variable-focus mechanism. FIG. 2(b) is a perspective view of the variable-focus mechanism, and FIG. 2(c) is an exploded perspective view of the variable-focus mechanism. In this embodiment, the variable-focus mechanism mainly includes a movable lens 142, a lens holder 131, and a vibration motor 15. The lens holder 131 that holds the movable lens 142 has a through-hole 131a. A guide bar 132 is inserted into the through-hole 131a, so that the lens holder 131 is movable in direction D1 but is limited in movement in a direction perpendicular to direction D1. The lens holder 131 also has a connecting member 136 and a torsion spring 137. The connecting member 136 is held so that it can rotate in direction D2, which is the circumferential direction about direction D1, relative to the lens holder 131. The torsion spring 137 generates a biasing force that biases the connecting member 136 in direction D2. The connecting member 136 has a spherical protrusion 136a.

[0020] The vibration motor 15 is mainly composed of a movable part 16 and a fixed part 17 that sandwiches the movable part 16 and is fixed to the first exterior casing 134. The movable part 16 has a groove 162a that receives the spherical protrusion 136a, and the fixed part 17 has an opening 175a into which the connecting member 136 is inserted. The spherical protrusion 136a of the connecting member 136 is biased against the groove 162a, thereby connecting the movable part 16 of the vibration motor 15 to the lens holder 131. In this configuration, when the vibration motor 15 is driven, the lens holder 131 and the movable lens 142 are driven in the drive direction D1. This action makes it possible to change the depth of the virtual image on the display 141 as seen by the user.

[0021] The configuration for holding lens holder 131 so that it can move in direction D1 and so that its movement is restricted in a direction perpendicular to direction D1 is not limited to the configuration using guide bar 132. For example, a configuration in which a protrusion provided on lens holder 131 is guided to move in direction D1 by a groove provided on the inner wall of first exterior 134 that is parallel to direction D1, or any other known configuration may be used.

[0022] Furthermore, the configuration for connecting the lens holder 131 and the vibration type motor 15 is not limited to the configuration shown in Fig. 2. For example, the vibration type motor 15 may have a torsion spring 137 and a connecting member 136, or a groove may be provided in the connecting member 136 and a spherical protrusion may be provided on a member that comes into contact with the connecting member 136.

[0023] Next, we will explain the vibration motor 15, which is an actuator used in the variable-focus mechanism. FIG. 3 illustrates the structure of the vibration motor 15, with FIGS. 3(a) and 3(b) each being an exploded perspective view of the vibration motor 15 viewed from a different angle. In the vibration motor 15, the fixed part 17 has a vibrator 171 that vibrates when a voltage is applied, and the movable part 16 has a contact member 161 that comes into contact with a protrusion on the vibrator 171. In addition to the vibrator 171, the fixed part 17 also includes a holding mechanism for the vibrator 171 and a pressure mechanism that presses the vibrator 171 against the contact member 161 with a predetermined pressure force F1. The holding mechanism includes a vibrator holding frame 172, a connection plate 173, a fixed frame 174, and a fixed guide member 175, while the pressure mechanism includes a pressure spring 176, a pressure plate 177, and a buffer plate 178. In addition to the contact member 161, the movable part 16 also includes a movable guide member 162 that serves as a holding mechanism for the contact member 161. The rolling member 18 is disposed between the movable guide member 162 and the fixed guide member 175, and the rolling member 18 is sandwiched between the movable guide member 162 and the fixed guide member 175 using a pressure force F1 generated by the pressure mechanism. The pressure direction by the pressure force F1 of the pressure mechanism is referred to as a pressure direction D3.

[0024] The vibrator 171 is a structure in which, for example, a piezoelectric element 171a and an elastic member 171b having two protrusions 171c are attached. The piezoelectric element 171a is, for example, a PZT (lead zirconate titanate) plate, and the elastic member 171b is a metal plate on which the two protrusions 171c are formed. When an appropriate AC voltage is applied to the piezoelectric element 171a, an elliptical motion can be generated at the tip of the protrusion 171c, and by transmitting this elliptical motion to the contact member 161, a driving force in the driving direction D1 is generated.

[0025] The vibrator holding frame 172 and the fixed frame 174 are frames that hold the vibrator 171, and the connecting plate 173 is a thin metal plate. The vibrator holding frame 172 is directly bonded to the vibrator 171 to hold it. Because the connecting plate 173 is a thin metal plate, it has high rigidity in the planar direction but low rigidity in the bending direction. Therefore, by connecting the vibrator holding frame 172 and the fixed frame 173 with the connecting plate 174, the vibrator 171 and the vibrator holder 172 can move relative to the fixed frame 173 in the pressure direction D3 and are held without any play in the drive direction D1. The fixed guide member 175 is a plate-shaped member that is provided with an opening 175a into which the connecting member 136 is inserted, a guide groove 175b that extends in the drive direction D1, and a hook 175c.

[0026] The contact member 161 is a substantially rectangular parallelepiped member whose sliding surface 161a comes into contact with the protrusion 171c of the vibrator 171. The movable guide member 162 is a member provided with a groove 162a to which the spherical protrusion 136a of the connecting member 136 is biased, a guide groove 162b extending in the driving direction D1, and a guide surface 162c. The contact member 161 is fastened to the movable guide member 162, which is a holding member that holds the contact member 161, with screws to form an integrated unit.

[0027] The pressure spring 176 is a tension coil spring, and the pressure plate 177 is a plate-shaped member having a hook 177a. One end of the pressure spring 176 is hooked onto the hook 175c of the fixed guide member 175, and the other end is hooked onto the hook 177a of the pressure plate 177, causing elastic deformation, thereby generating a pressure force F1 that urges the vibrator 171 against the contact member 161. The buffer plate 178 is a plate-shaped member to which, for example, felt 178a is attached. The pressure force F1 generated by the pressure spring 176 is transmitted to the vibrator 171 via the pressure plate 177 and the buffer plate 178. The vibrator 171 and the vibrator holding frame 172 are held so as to be movable in the pressure direction D3, and therefore the pressure force F1 is not impeded by the vibrator holding mechanism, and the protrusion 171c of the vibrator 171 is pressed against the sliding surface 161a of the contact member 161.

[0028] Guide groove 175b of fixed guide member 175 and guide groove 162b and guide surface 162c of movable guide member 162 are arranged in opposing positions, and balls, which are rolling members 18, are arranged between them. Rolling members 18 are sandwiched between fixed guide member 175 and movable guide member 162 by a reaction force of pressure F1. With the above-mentioned configuration, movable guide member 162 is held so as to be movable in driving direction D1 relative to fixed guide member 175. Note that the configuration of the vibration-type motor described above is one example, and the vibrator holding mechanism and pressure mechanism may have known configurations as long as they are configured to linearly drive a driven body using a driving force generated by vibrating a vibrating body.

[0029] Next, we will explain the influence of the driving noise of the actuators included in the image display device wearable on the user's head. FIG. 4 is a diagram showing the influence of the driving noise of the actuators included in the image display device wearable on the user's head. As shown in FIG. 4(a), two optical units 13 and 13' are arranged side by side in the X direction in the HMD main body 11 to display images to the left and right eyes, respectively. When worn, the area A1 adjacent to the user's nose and the area A2 adjacent to the forehead have limited space for arranging components to avoid interference with the user, making it difficult to arrange the actuators used in the variable-focus mechanism. For this reason, for example, it is preferable to arrange the actuator of the left-eye optical unit 13 in area A3, which is on the opposite side of the optical axis O1 from the optical axis O1' of the other optical unit 13'. Similarly, it is preferable to arrange the actuator of the right-eye optical unit 13' in area A3', which is on the opposite side of the optical axis O1' from the optical axis O1 of the other optical unit 13.

[0030] For this reason, in the HMD 1 according to this embodiment, the vibration type motor 15, which is an actuator, is arranged in the areas indicated by areas A4 and A4' within areas A3 and A3'. Note that, as long as it is within areas A3 and A3', it may be arranged in an area that is offset in the X direction or Y direction from areas A4 and A4' so as not to interfere with the lens holder 131.

[0031] On the other hand, if the actuators are arranged in the areas A3 and A3', the driving sounds of the actuators may travel along the paths S1 and S1' to reach the side surfaces of the HMD main body 11 in the X direction and be heard by the user.

[0032] For example, Fig. 4(b) is a diagram showing the positional relationship between the user 3 and the optical units 13, 13', and as shown in Fig. 4(b), the drive sound that reaches the side of the HMD main body 11 is then diffused along the path indicated by S2, and there is a risk that part of the drive sound may reach the ear 31 of the user 3. If the drive sound of the actuator that drives the movable lens 142 in response to the image is heard while the user 3 is watching video content, there is a risk that the sense of immersion in the video content will be impaired.

[0033] Here, the features of the HMD 1 according to this embodiment will be described. First, the HMD 1 has a vibration-type motor 15 as an actuator for driving a movable lens 142, which is one of the optical members. The vibration-type motor 15 has a vibrator 171 and a contact member 161 that comes into contact with the vibrator 171. Second, when viewed from the optical axis direction of the optical member of the first optical unit, the vibration-type motor 15 of the first optical unit is arranged on the opposite side of the optical axis of the optical member of the first optical unit from the side on which the second optical unit is arranged. Here, the first optical unit corresponds to one of the optical units 13 and 13′, and the second optical unit corresponds to the other of the optical units 13 and 13′. Third, in the vibration-type motor 15 arranged as described above, the contact member 161 is arranged farther from the optical member included in the optical unit to which it belongs than the vibrator 171. That is, in the vibration-type motor 15 arranged as described above, the vibrator 171 and the contact member 161 are arranged in this order in a direction away from the optical axis of the optical unit.

[0034] The influence of the driving noise of the actuator in the HMD 1 according to this embodiment having such a configuration will be described with reference to FIG. 5. FIG. 5 is a diagram showing the influence of the driving noise of the actuator provided in the HMD 1 according to this embodiment. FIG. 5(a) is an XY cross-sectional view of the optical unit 13. A vibration-type motor generally generates a driving force by vibrating a vibrator at a frequency outside the audible range, and is therefore an actuator whose driving noise is difficult for the user to hear. However, there is a risk that vibrations propagating to peripheral components of the vibrator will generate vibrations in the audible range, which may be heard by the user as driving noise. This driving noise is caused by the vibration of the vibrator propagating to peripheral components of the vibrator, and is therefore more likely to be generated on the vibrator side, where the vibration of the vibrator is more easily propagated, than on the contact member side.

[0035] In this embodiment, as shown in FIG. 5(a), in the optical unit 13 of the HMD 1, the vibration motor 15 is disposed in an area A3 that is on the opposite side of the optical axis O1' of the other optical unit 13' with respect to the optical axis O1. Furthermore, in the vibration motor 15, the vibrator 171 and the contact member 161 are layered in this order in a direction away from the optical axis O1. That is, the contact member 161 is disposed on the outside of the HMD 1, and the vibrator 171 is disposed on the inside. With this arrangement, most of the drive sound generated by the vibration motor 15 is directed in the direction of the optical axis O1, as indicated by S3. Therefore, it is possible to reduce the drive sound directed toward the side surface of the HMD main body 11 in the X direction.

[0036] Fig. 5(b) shows how the drive sound that reaches the side of the HMD main body 11 is diffused to the surroundings, similar to Fig. 4(b), but the drive sound that reaches the side of the HMD main body 11 is smaller in Fig. 5(b) than in Fig. 4(b), and the drive sound is less likely to reach the user's ears. This makes it possible to prevent the user from losing their sense of immersion in the video content.

[0037] In the HMD 1 according to this embodiment, the vibration motor 15 is arranged so as to be completely contained within the areas A3 and A3' shown in Fig. 4(a). However, if at least a part of the vibration motor 15 is arranged within the areas A3 and A3', the same effect as this embodiment can be obtained.

[0038] It has been mentioned that one of the features of the HMD 1 is that the vibrator 171 and the contact member 161 are stacked in this order in the direction away from the optical axis O1 in the optical unit 13. This arrangement means that at least a part of the vibrator 171 is included within the area connecting the optical axis O1 and the contact member 161 in the direction perpendicular to the optical axis O1.

[0039] 2(a), the first exterior 134 has a through-hole 134a on the optical axis O1 side of the vibration motor 15. In each of the optical units 13 and 13′, a second exterior 135 is disposed on the side opposite the optical axis O1 side of the vibration motor 15 so as to cover the vibration motor 15.

[0040] In this configuration, the through-hole 134a in the first exterior 134 causes the drive sound passing through the path S3 in Fig. 5(a) to travel in the direction of the optical axis O1 of the optical unit 13 without being reflected by components near the vibrator 171. Furthermore, the drive sound traveling along the path S4 is reflected by the second exterior 135. This makes it possible to suppress the drive sound of the vibration motor 15 from diffusing to the outside from the HMD 1.

[0041] Another possible route through which the driving sound of the vibration motor 15 may be diffused to the outside is shown in Fig. 6. Fig. 6 is a diagram showing the influence of the driving sound of the actuator provided in the HMD 1 according to this embodiment, and the horizontal plane P1 and the central plane P2 in Fig. 6 correspond to the horizontal plane P1 and the central plane P2 in Fig. 1(b). In this embodiment, as shown in Figs. 2(b) and 2(c), the optical unit 13 has a connecting member 136 that connects the vibration motor 15 and the movable lens 142, which is an optical member driven by the vibration motor 15. In this embodiment, the vibration motor 15 has an opening 175a into which the connecting member 136 is inserted.

[0042] Fig. 6(a) is an XY cross-sectional view of the optical unit 13. As shown in Fig. 6(a), part of the drive sound generated from the peripheral parts of the vibrator 171 travels to the outside via a path S5 that passes through the opening 175a. If this path S5 were in the same direction as path S4, the amount of drive sound diffusing to the outside from the side of the HMD main body 11 would increase.

[0043] In contrast, in the HMD 1 of this embodiment, the opening 175a is arranged in a direction substantially perpendicular to the direction in which the vibrator 171 and the contact member 162 are aligned. With this configuration, it is possible to prevent the drive sound passing through the path S5 from diffusing from the side surface of the HMD main body 11 to the outside.

[0044] If the direction in which vibrator 171 and contact member 162 are aligned is inclined with respect to horizontal plane P1, opening 175a should be provided on the side closer to central plane P2 of surfaces 15a and 15b parallel to the direction in which vibrator 171 and contact member 162 are aligned. That is, opening 175a should be provided so that path S5 faces the direction toward central plane P2 of directions D4 and D5 perpendicular to the direction in which vibrator 171 and contact member 162 are aligned.

[0045] Furthermore, when the vibrator 171 is held by the movable part 16, the vibrator 171 moves in the drive direction D1, which changes the distance between the user and the vibrator 171 in the drive direction D1, and this may make the drive sound of the vibration motor 15 more audible to the user depending on the position of the vibrator 171. However, in this embodiment, the vibrator 171 is held by the fixed part 17, so the distance between the user and the vibrator 171 in the drive direction D1 does not change, and it is possible to prevent the drive sound of the vibration motor 15 from becoming more audible to the user.

[0046] (Second embodiment) Next, a head-mounted display (HMD2) according to a second embodiment, which is an image display device that can be worn on the user's head and used, will be described. This embodiment has the same configuration as the first embodiment, except that the optical units 23, 23' of the HMD2 are different from the optical units 13, 13' of the HMD1 of the first embodiment. The differences from the first embodiment will be described in detail below with reference to FIGS. 7 and 8.

[0047] FIG. 7 shows the configuration of the variable-focus mechanism of this embodiment, with FIG. 7(a) being an exploded perspective view of the left-eye optical unit 23. The left-eye optical unit 23 and the right-eye optical unit 23' are mirror-symmetric in the X direction, similar to the optical units 13 and 13', and therefore a description of the right-eye optical unit 23' will be omitted. The optical unit 23 mainly includes a display 241, a movable lens 242, a lens holder 231, a guide bar 232, a vibration motor 25, a front cover 233, a first exterior casing 234, and a second exterior casing 235. The optical unit 23 of this embodiment differs from the optical unit 13 of the first embodiment in that it includes a sound-absorbing material 238 between the vibration motor 25 and the second exterior casing 235. The sound-absorbing material 238 is, for example, a porous sheet material. The display 241, the movable lens 242, the lens holder 231, the guide bar 232, the front cover 233, the first exterior 234, and the second exterior 235 are the same as the components of the HMD 1, and therefore a description thereof will be omitted.

[0048] FIG. 7(b) is an exploded perspective view of the vibration motor 25, seen from the same angle as FIG. 3(b), illustrating the structure of the vibration motor 25. The vibration motor 25 is similar to the vibration motor 15 in that it has a vibrator 271 and a contact member 261. The vibration motor 25 is also similar to the vibration motor 15 in that it has a holding mechanism for the vibrator 271 (vibrator holding frame 272, connection plate 273, fixed frame 274, fixed guide member 275) and a pressure mechanism for pressing the vibrator 271 against the contact member 261 (pressure spring 276, pressure plate 277, buffer plate 278). The vibration motor 25 of this embodiment includes a damping member 263 between the contact member 261 and the movable guide member 262. The damping member 263 is, for example, a rubber sheet, and damps unnecessary vibrations of the contact member 261 by coming into contact with the contact member 261.

[0049] The influence of the driving sound of the actuator in the HMD 2 according to this embodiment having such a configuration will be described with reference to Fig. 8. Fig. 8 is a diagram showing the influence of the driving sound of the actuator provided in the HMD 2 according to this embodiment.

[0050] In the HMD2 of this embodiment, the vibrator 271, contact member 261, and damping member 263 are layered in this order in the direction away from the optical axis O1. In this configuration, when the drive sound emitted from the peripheral components of the vibrator passes through path S4, it passes through the damping member 263. Therefore, the damping effect of the damping member 263 can reduce the drive sound passing through path S4 more than in the first embodiment.

[0051] Furthermore, in the HMD 2 of this embodiment, the vibration motor 25, the sound-absorbing material 238, and the second exterior casing 235 are layered in this order in the direction away from the optical axis O1, and the sound-absorbing material 238 is in contact with both the vibration motor 25 and the second exterior casing 235. In this configuration, the sound-absorbing material 238 is in contact with the vibration motor 25, thereby attenuating the vibration of the vibration motor 25 and reducing the total amount of drive noise generated by the vibration motor 25. Furthermore, when the reduced drive noise passes through path S4, it passes through the sound-absorbing material 238. Therefore, the drive noise passing through path S4 can be reduced more than in the first embodiment. By reducing the drive noise that passes through path S4 and reaches the side of the HMD body of the HMD 2, the drive noise of the vibration motor 25 that diffuses to the outside from the HMD 2 can be suppressed as shown in FIG. 8(b).

[0052] In the present embodiment, the damping member 263 and the sound-absorbing material 238 are provided to suppress the driving noise of the vibration motor 25 that diffuses from the HMD 2 to the outside. However, either the damping member 263 or the sound-absorbing material 238 may be omitted. Alternatively, the sound-absorbing material 238 may be in contact with only one of the vibration motor 25 and the second exterior 235. Alternatively, the sound-absorbing material 238 may be in contact with the second exterior 235 from the outside. Alternatively, the sound-absorbing material 238 may be disposed not only between the vibration motor 25 and the second exterior 235 but also in contact with the inner wall of the first exterior 234. By widening the range in which the sound-absorbing material 238 is disposed in this manner, the driving noise that passes through path S3 can be made less likely to reach the user's ears. Either of these configurations can suppress the driving noise of the vibration motor that diffuses from the HMD to the outside more effectively than the first embodiment.

[0053] As described above, by suppressing the driving noise of the vibration motor that is diffused to the outside from the HMD, it is possible to prevent a decrease in the sense of immersion caused by the motor moving part of the mechanism that shows the 3D image to the user.

[0054] The disclosure of this embodiment includes the following configuration.

[0055] (Configuration 1) An image display device that can be worn on a user's head and used, a first optical unit that outputs one of an image for the left eye and an image for the right eye; a second optical unit that outputs the other of the left-eye image and the right-eye image; a motor having a vibrator that vibrates when a voltage is applied thereto and a contact member that comes into contact with a protrusion provided on the vibrator, and generating a driving force that moves an optical member included in the first optical unit by vibrating the vibrator; When viewed from the optical axis direction of the optical member, the motor is disposed on an opposite side of the optical axis of the optical member from a side on which the second optical unit is disposed, The image display device is characterized in that the contact member is disposed at a position farther from the optical member than the vibrator.

[0056] (Configuration 2) 2. The image display device according to claim 1, wherein the motor generates a driving force that moves the optical member in a direction parallel to the optical axis.

[0057] (Configuration 3) 3. The image display device according to configuration 1 or 2, wherein the optical member and the contact member are moved by the vibration of the vibrator.

[0058] (Configuration 4) 4. The image display device according to any one of configurations 1 to 3, further comprising a damping member in contact with the contact member.

[0059] (Configuration 5) a holding member for holding the contact member, 5. The image display device according to configuration 4, wherein the attenuation member is disposed between the contact member and the holding member.

[0060] (Configuration 6) a cover member surrounding the motor when viewed from the optical axis direction of the optical member; 6. The image display device according to claim 1, further comprising a sound absorbing material disposed between the cover member and the contact member.

[0061] (Configuration 7) 6. The image display device according to claim 1, further comprising: a sound-absorbing material arranged on the opposite side of the contact member from the side on which the vibrator is arranged in the direction in which the vibrator and the contact member are aligned.

[0062] (Configuration 8) 8. The image display device according to any one of configurations 1 to 7, wherein the optical member is a lens that guides an image displayed on a display section included in the first optical unit to a user.

[0063] (Configuration 9) 8. The image display device according to claim 1, wherein the optical member is a display section included in the first optical unit. [Explanation of symbols]

[0064] 1, 2 HMD 11, 21 HMD body 13, 13', 23, 23' Optical Unit 134, 234 First exterior 135, 235 Second exterior 136 Connecting member 141, 241 display 142, 242 movable lens 15, 25 Vibration motor 16 Moving parts 161, 261 Friction members 17 Fixed part 171, 271 vibrator 238 Sound-absorbing material 263 Damping members

Claims

1. An image display device that can be worn on a user's head and used, a first optical unit that outputs one of an image for the left eye and an image for the right eye; a second optical unit that outputs the other of the image for the left eye and the image for the right eye; a motor having a vibrator that vibrates when a voltage is applied thereto and a contact member that comes into contact with a protrusion provided on the vibrator, and generating a driving force that moves an optical element included in the first optical unit by vibrating the vibrator; When viewed from the optical axis direction of the optical member, the motor is disposed on an opposite side to a side on which the second optical unit is disposed with respect to an optical axis of the optical member; The image display device is characterized in that the contact member is disposed at a position farther from the optical member than the vibrator.

2. 2. The image display device according to claim 1, wherein the motor generates a driving force that moves the optical member in a direction parallel to the optical axis.

3. 2. The image display device according to claim 1, wherein the optical member and the contact member are moved by the vibration of the vibrator.

4. 2. The image display device according to claim 1, further comprising a damping member in contact with the contact member.

5. a holding member for holding the contact member, 5. The image display device according to claim 4, wherein the damping member is disposed between the contact member and the holding member.

6. a cover member surrounding the motor when viewed from the optical axis direction of the optical member; 2. The image display device according to claim 1, further comprising a sound absorbing material disposed between the cover member and the contact member.

7. 2. The image display device according to claim 1, further comprising: a sound absorbing material disposed on the side of the contact member opposite to the side on which the vibrator is disposed in the direction in which the vibrator and the contact member are aligned.

8. 2. The image display device according to claim 1, wherein the optical member is a lens that guides an image displayed on a display unit included in the first optical unit to a user.

9. 2. The image display device according to claim 1, wherein the optical member is a display portion included in the first optical unit.

Images