Video display device, control method thereof, and program

Abstract

To provide a video display device configured to suppress a difference in subject distance of an image during video display, the difference being caused when diopter is adjusted on video display means with an inter-pupil distance unadjusted.SOLUTION: A video display device 30 includes a pair of video display sections 14R and 14L each having display units 1R, 1L and eyepiece optical systems 2R, 2L. First driving means (18R, 18L) is configured to modify optical positional relationship between the display units 1R, 1L and the eyepiece optical systems 2R, 2L. Second driving means (21R, 21L) is configured to modify a distance between the pair of video display sections 14R and 14L. An inter-pupil distance adjustment section 33 adjusts a distance between the video display sections 14R and 14L by the second driving means in accordance with results detected by inter-pupil distance detection sections 27R, 27L. After the inter-pupil distance adjustment, diopter adjustment sections 15R, 15L perform diopter adjustment related to the video display sections 14R, 14L by the first driving means.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a technique for adjusting the interpupillary distance and diopter in an image display device. [Background technology]

[0002] Interpupillary distance adjustment in an image display device involves changing the distance between the left and right image display means in accordance with the user's interpupillary distance. Other adjustments include adjustment of the user's diopter and adjustment of diopter in accordance with the subject distance of the displayed image. For example, the power is adjusted in the eyepiece to match the user's visual acuity. Patent Document 1 discloses a configuration in which these adjustments are motorized. By motorizing the adjustments, the user no longer needs to make the adjustments manually, and the adjustment operation is automated as part of the operation of the image display device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-68670 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the image display device disclosed in Patent Document 1 does not clearly disclose the order of interpupillary distance adjustment and diopter adjustment. Therefore, if diopter adjustment is performed before interpupillary distance adjustment, the parallax may shift by the amount of interpupillary distance deviation relative to the image display means, and the subject distance perceived by the user may shift by the amount of parallax deviation. Details of this will be described later using Figure 8. An object of the present invention is to provide an image display device that can prevent a deviation in the subject distance of an image when the image is displayed due to diopter adjustment being performed while the interpupillary distance remains shifted relative to the image display means. [Means for solving the problem]

[0005] An image display device according to an embodiment of the present invention comprises a plurality of image display means, each having a display and a display optical system; a first adjustment means for adjusting the diopter of the image display means by changing the optical positional relationship between the display and the display optical system; a detection means for detecting the interpupillary distance of a user; and a second adjustment means for adjusting the distance between the plurality of image display means according to the detection result of the detection means, thereby adjusting the distance corresponding to the interpupillary distance, and is characterized in that the second adjustment means adjusts the distance corresponding to the interpupillary distance before the first adjustment means adjusts the diopter. [Effects of the Invention]

[0006] According to the image display device of the present invention, it is possible to provide an image display device that can suppress the occurrence of a shift in the subject distance of the image when the image is displayed, which occurs when diopter adjustment is performed while the interpupillary distance remains shifted relative to the image display means. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic diagram showing the appearance of a video display device according to an embodiment of the present invention; [Figure 2] 1 is a diagram illustrating a configuration of a video display device according to a first embodiment. [Figure 3] 1 is a block diagram showing the entire system of a video display device according to an embodiment of the present invention; [Figure 4] 4 is a flowchart illustrating an operation in the present embodiment. [Figure 5] 10 is a flowchart illustrating diopter adjustment for the left and right eyes. [Figure 6] 10 is a flowchart illustrating diopter adjustment for the right eye. [Figure 7] 10 is a flowchart illustrating a video display process. [Figure 8] FIG. 1 is an explanatory diagram of a problem to be solved. [Figure 9] 10A and 10B are diagrams illustrating the effects of the present embodiment. [Figure 10] FIG. 10 is a diagram illustrating the configuration of a video display device according to a second embodiment. [Figure 11] FIG. 10 is a diagram illustrating the configuration of a video display device according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In the embodiment, a head-mounted display that is worn on the user's head and capable of stereoscopic display etc. will be shown as an example of an image display device.

[0009] [First embodiment] A first embodiment of the present invention will be described with reference to Figures 1 to 9. In each figure, the optical axis direction of the display optical system (hereinafter also referred to as the eyepiece optical system) is defined as the Z-axis direction, the direction in which the right eye 5R and left eye 5L of the user, who is the observer, are aligned is defined as the X-axis direction, and the direction perpendicular to the X-axis and Z-axis directions is defined as the Y-axis direction. On the X-axis, the direction of the right eye 5R is defined as the +X direction, and the direction of the left eye 5L is defined as the -X direction. On the Y-axis, the direction of the top of the user's head is defined as the +Y direction, and the direction opposite the top of the head is defined as the -Y direction. On the Z-axis, the direction in which the user views the image is defined as the +Z direction, and the opposite direction is defined as the -Z direction.

[0010] 1 is a schematic diagram showing the appearance of an image display device according to this embodiment. The image display device 30 has a belt part 30a for being worn on a user's head 5. The user observes images displayed by the image display device 30 with their right eye 5R and left eye 5L.

[0011] 2A and 2B are diagrams illustrating the configuration of the image display device 30. FIG. 2A is a schematic diagram of the image display device 30 as viewed from the +Y direction. FIG. 2B is a schematic diagram of the image display device 30 as viewed from the -Z direction, with some of the components indicated by two-dot chain lines. FIG. 2C is a schematic diagram of the image display device 30 as viewed from the +X direction.

[0012] First, the right-eye image display unit 14R will be described. The right-eye image display unit 14R includes a right-eye display 1R, a guide shaft 12R, and a display holder 13R. The right-eye display 1R is held by the display holder 13R and is configured to be movable in the Z-axis direction while being guided by the guide shaft 12R. The right-eye eyepiece optical system 2R is an optical system corresponding to the user's right eye 5R. A display light beam of an image displayed on the right-eye display 1R reaches the user's right eye 5R through the right-eye eyepiece optical system 2R. The right-eye display 1R is configured to be able to adjust the diopter of the display light beam reaching the user's right eye 5R by moving in the Z-axis direction along the guide shaft 12R.

[0013] The right-eye diopter adjustment unit 15R includes a vibrator holding member 16R, a guide shaft 17R, a vibrator 18R, and a friction member 19R. The vibrator 18R, which serves as a vibration member, is a driving source that generates a driving force for, for example, an ultrasonic motor. The vibrator 18R generates a high-frequency elliptical motion at the contact point with the friction member 19R, thereby generating a driving force in the Z-axis direction for the friction member 19R, and is able to move in the Z-axis direction relative to the friction member 19R. The vibrator 18R is held by a vibrator holding member 16R. The vibrator holding member 16R is configured to be movable in the Z-axis direction by being guided by a guide shaft 17R.

[0014] In this embodiment, the vibrator holding member 16R, the guide shaft 17R, the vibrator 18R, and the friction member 19R constitute a right-eye diopter adjusting section 15R. The vibrator 18R constitutes a first driving means together with a vibrator 18L, which will be described later.

[0015] The transducer holding member 16R has a protrusion, and the display holding member 13R has a V-shaped groove corresponding to the protrusion. The protrusion of the transducer holding member 16R engages with the V-shaped groove of the display holding member 13R, allowing the transducer holding member 16R and the display holding member 13R to move together in the Z-axis direction. In other words, the driving force of the transducer 18R in the Z-axis direction can move the right-eye display 1R in the Z-axis direction. This allows the right-eye diopter adjustment unit 15R to have a diopter adjustment function for the right-eye image display unit 14R. For example, when the diopter of the right-eye image display unit 14R is changed toward infinity, the right-eye display 1R moves in the +Z direction, and when it is changed toward near, the right-eye display 1R moves in the -Z direction.

[0016] Diopter adjustment requires frequent and highly accurate reciprocating motion of the diopter adjustment member in response to changes in the subject distance in the displayed image. In the image display device 30, an ultrasonic motor that generates linear thrust through high-frequency vibration of the vibrator 18R is used as the drive source for the right-eye diopter adjustment unit 15R. The ultrasonic motor has strong thrust and can directly drive the right-eye display 1R without a speed reduction mechanism, making it possible to reciprocate the right-eye display 1R frequently and with high accuracy.

[0017] In the image display device 30, the right-eye image display unit 14R and the right-eye diopter adjustment unit 15R are disposed adjacent to each other in the X-axis direction. In the Y-axis direction, the right-eye image display unit 14R is larger than the right-eye diopter adjustment unit 15R, so the device size in the Y-axis direction depends on the size of the right-eye image display unit 14R. Therefore, even if the right-eye diopter adjustment unit 15R is made smaller, the image display device 30 does not become smaller. On the other hand, in the X-axis direction, the image display device 30 can be made smaller by the amount that the right-eye diopter adjustment unit 15R is made smaller. In other words, to make the image display device 30 smaller, the right-eye diopter adjustment unit 15R needs to be made smaller in the X-axis direction than in the Y-axis direction.

[0018] In the right-eye diopter adjustment unit 15R, the vibrator 18R generates a high-frequency elliptical motion at the contact point with the friction member 19R, thereby generating a driving force between the vibrator 18R and the friction member 19R. To achieve this, it is necessary to press the vibrator 18R against the friction member 19R. The right-eye diopter adjustment unit 15R is equipped with a pressing member (not shown). The pressing members are arranged adjacent to both sides of the vibrator 18R in the Y-axis direction, and are arranged to overlap the vibrator 18R in the X-axis direction when viewed from the Y-axis direction. This allows the right-eye diopter adjustment unit 15R to be made thinner in the X-axis direction. Details of the pressing member will be described in the embodiment described later.

[0019] The friction member 19R is disposed so that the normal direction of the friction surface 19R-a is parallel to the X-axis direction. With this arrangement, the direction in which the right-eye diopter adjustment unit 15R is thinnest is the X-axis direction, which contributes to the miniaturization of the image display device 30.

[0020] The left-eye image display unit 14L has a configuration symmetrical to the right-eye image display unit 14R with respect to a plane parallel to the YZ plane. Therefore, the components of the left-eye image display unit 14L will be designated by symbols obtained by replacing the R attached to the symbols of the components of the right-eye image display unit 14R with an L. In the above description of the right-eye image display unit 14R, the terms for the right eye will be read as those for the left eye, and R will be replaced with L, thereby omitting detailed description thereof. This method of omitting description will also be used in the embodiments described below.

[0021] In this embodiment, the vibrator holding member 16L, guide shaft 17L, vibrator 18L, and friction member 19L constitute a left-eye diopter adjustment unit 15L. When the diopter of the left-eye image display unit 14L is changed toward infinity, the left-eye display 1L moves in the +Z direction, and when the diopter is changed toward near, the left-eye display 1L moves in the -Z direction. The image display device 30 has separate right-eye diopter adjustment units 15R and 15L, allowing for individual adjustment for each eye. This allows for appropriate diopter adjustment even for users with different visual acuity between their left and right eyes. In this embodiment, a quiet ultrasonic motor is used as the drive source for the diopter adjustment units 15R and 15L, but the drive method for the drive source is not limited, and a voice coil motor or the like may also be used.

[0022] Next, we will explain the interpupillary distance adjustment unit 33. The interpupillary distance adjustment unit 33 includes motors 21R and 21L, lead screws 22R and 22L, and racks 23R and 23L. The motors 21R and 21L constitute second driving means.

[0023] The fixing member 20 holds a right-eye motor 21R and a left-eye motor 21L. A lead screw 22R is connected to the motor 21R, and a rack 23R is engaged with the lead screw 22R. Rotation of the motor 21R rotates the lead screw 22R, and the right-eye image display unit 14R, which is fixed to the rack 23R, moves in the X-axis direction. The right-eye image display unit 14R also includes a guided portion 25R. An X-axis guide mechanism is formed by the guided portion 25R engaging with a guide shaft 24R fixed to the fixing member 20. The right-eye image display unit 14R can move linearly in the X-axis direction when driven by the motor 21R. The right-eye image display unit 14R and the right-eye diopter adjustment unit 15R are coupled, so when driven by the motor 21R, the right-eye image display unit 14R and the right-eye diopter adjustment unit 15R can move together in the X-axis direction.

[0024] The left-eye side mechanism for adjusting the interpupillary distance can be understood by replacing the symbol R in the above description with the symbol L and reading the right eye as the left eye, and therefore a detailed description thereof will be omitted. The left-eye image display unit 14L can be moved linearly in the X-axis direction by driving the motor 21L. The left-eye image display unit 14L and the left-eye diopter adjustment unit 15L are coupled, so that the left-eye image display unit 14L and the left-eye diopter adjustment unit 15L can be moved integrally in the X-axis direction by driving the motor 21L. Note that, in this embodiment, lead-screw type motors 21R and 21L are used in the mechanism for adjusting the interpupillary distance, but the drive system of the drive source is not limited, and an ultrasonic motor, a voice coil motor, or the like may also be used.

[0025] The interpupillary distance detection unit 27R is located at a position offset in the -Y direction from the optical axis of the right-eye eyepiece optical system 2R at the -Z direction end of the right-eye image display unit 14R. The interpupillary distance detection unit 27R captures an image of the right eye 5R from an oblique direction with respect to the optical axis of the right-eye image display unit 14R. Similarly, the interpupillary distance detection unit 27L is located at a position offset in the -Y direction from the optical axis of the left-eye eyepiece optical system 2L at the -Z direction end of the left-eye image display unit 14L. The left-eye image display unit 14L captures an image of the left eye 5L from an oblique direction with respect to the optical axis of the left-eye image display unit 14L. The interpupillary distance of the user is detected by detecting the positions of the right eye 5R and left eye 5L from information about the multiple images captured by the interpupillary distance detection units 27R and 27L.

[0026] In the interpupillary distance adjustment unit 33, the motors 21R and 21L are driven based on the interpupillary distance detected by the interpupillary distance detection units 27R and 27L. By driving the motors 21R and 21L to change the distance between the right eye image display unit 14R and the left eye image display unit 14L, the interpupillary distance adjustment unit 33 makes an adjustment corresponding to the interpupillary distance.

[0027] Next, the image display device 30 will be described with reference to Fig. 3. Fig. 3 is a block diagram showing the overall system configuration of the image display device 30. The image display device 30 is equipped with an arithmetic processing unit 29 such as a CPU (Central Processing Unit). The arithmetic processing unit 29 is connected to a right eye display 1R, a left eye display 1L, a right eye diopter adjustment unit 15R, a left eye diopter adjustment unit 15L, interpupillary distance detection units 27R and 27L, and an interpupillary distance adjustment unit 33, and the arithmetic processing unit 29 controls each unit.

[0028] Video display device 30 further includes a power supply 31, a wireless unit 32, and speakers 28R and 28L. Each unit is connected to a processing unit 29. By connecting to a network via wireless unit 32, a user can view video content and the like on video display device 30.

[0029] The operation of the video display device 30 will be described with reference to Figures 4 to 7. A program corresponding to the flowcharts of Figures 4 to 7 is stored in a storage unit within the arithmetic processing unit 29. The following processing is realized by the CPU executing the program.

[0030] 4 is a flowchart illustrating the operation of the entire system of image display device 30. First, in S101, a process is performed to detect whether image display device 30 is attached to the user's head 5. Whether or not it is attached to the head 5 is detected based on the detection signals from interpupillary distance detection units 27R and 27L. When image display device 30 is attached to the user's head 5, the process proceeds to S102.

[0031] In S102, the right-eye diopter adjustment unit 15R and the left-eye diopter adjustment unit 15L perform processing to move the diopters of the right-eye image display unit 14R and the left-eye image display unit 14L a predetermined amount toward infinity. The right-eye display unit 1R and the left-eye display unit 1L move in the +Z direction. Each image display unit moves to a position equivalent to infinity, or to a position corresponding to a diopter shifted a predetermined amount from infinity toward the near side according to the user's eyesight.

[0032] In S103, the calculation processing unit 29 performs processing to display an adjustment index for the interpupillary distance (IPD) on the right eye display 1R and the left eye display 1L. IPD is an abbreviation for "Inter Pupilary Distance." An adjustment index is displayed on each display so that the user's eyes are directed toward infinity when the user is in a relaxed state.

[0033] In S104, the positions of the right eye 5R and the left eye 5L are detected from the image information captured by the interpupillary distance detection units 27R and 27L, and processing for detecting the interpupillary distance of the user is performed.

[0034] In S105, the interpupillary distance is adjusted by changing the distance between the right-eye image display unit 14R and the left-eye image display unit 14L based on the interpupillary distance detected in S104. In the image display device 30, the diopter drive (towards infinity) in S102 moves the image display device 30 toward infinity, and then IPD detection in S104 is performed. This makes it possible to detect the interpupillary distance with the user's eyes facing straight in the +Z direction. In other words, it is possible to prevent the interpupillary distance from being detected correctly because the user's eyes are tilted inward.

[0035] In S200, the arithmetic processing unit 29 executes a diopter adjustment process. The diopter adjustment is performed for the right eye image display unit 14R and the left eye image display unit 14L by changing the optical positional relationship between the displays 1R, 1L and the eyepiece optical systems 2R, 2L. Next, in S300, the arithmetic processing unit 29 executes an image display process. The process displays an image that reproduces parallax based on the diopter according to the subject distance.

[0036] Next, the diopter adjustment (FIG. 4: S200) will be described with reference to the flowchart of Fig. 5. First, the diopter adjustment process for the right eye is executed in S210. The diopter for the right eye is adjusted to match the visual acuity of the user's right eye.

[0037] In S220, diopter adjustment for the left eye is performed. The diopter for the left eye is adjusted to match the visual acuity of the user's left eye. Diopter adjustment then ends. In the image display device 30, diopter adjustment is performed separately for the right eye and the left eye. This allows appropriate diopter adjustment to be performed even for users with different visual acuity between their left and right eyes. Note that the order of S210 and S220 may be reversed, or the order of processing may be changed as appropriate depending on the user's dominant eye.

[0038] Next, the diopter adjustment (right eye) shown in S210 of FIG. 5 will be described with reference to the flowchart of FIG. 6. First, in S211, diopter drive processing toward infinity is executed. The right eye diopter adjustment unit 15R changes the diopter of the right eye image display unit 14R toward infinity by a predetermined amount. When driven toward infinity, the right eye display unit 1R and the left eye display unit 1L are moved in the +Z direction. Each display is driven by a movement amount up to a position where the diopter corresponds to infinity. Alternatively, the movement amount may be determined so that the diopter position is shifted a predetermined amount from the position corresponding to infinity according to the user's eyesight.

[0039] In S212, a process for displaying a diopter adjustment index is executed. The diopter adjustment index is displayed on the right eye display 1R. For the adjustment index, for example, an index with an easy-to-see checkerboard pattern is used so that it is easy for the user to see whether the diopter is correct (high contrast, sharp edges). In addition, the right eye display 1R also displays information about the diopter position so that the user can select the position where the diopter is correct in the optimal diopter position selection (right eye) shown in S215, which will be described later.

[0040] In S213, the diopter drive process (one step toward the near side) is executed, and the diopter position is changed by one step toward the near side. The right eye diopter adjustment unit 15R moves the right eye display device 1R in the -Z direction to change the diopter position toward the near side.

[0041] In S214, a determination process is executed as to whether the diopter position has reached the close end. If it is determined that the diopter position has reached the close end, the process proceeds to S215. If it is determined that the diopter position has not reached the close end, the process returns to S212 and the display of the adjustment index continues.

[0042] In S215, a process for selecting the optimal diopter position is executed. The user selects the diopter position when the diopter was most correct. In S216, a diopter drive process is executed according to the selected position. The diopter adjustment unit for the right eye 15R performs diopter adjustment so that the diopter position selected in S215 is reached. Then, the diopter adjustment (right eye) of S210 ends.

[0043] The diopter adjustment (left eye) process shown in S220 in Fig. 5 is the same as the diopter adjustment (right eye) process in S210. In the above description of S210, the right eye can be read as the left eye, so detailed description thereof will be omitted.

[0044] The video display process shown in S300 in Fig. 4 will be described with reference to the flowchart in Fig. 7. First, in S301, a process for acquiring video and subject distance information is executed. Video display device 30 is connected to the network via wireless unit 32. Processing unit 29 acquires a video signal of the video content and distance information corresponding to the subject contained in the video signal.

[0045] The processing of S302 and S303 and the processing of S304 and S305 are executed in parallel. In S302, the calculation processing unit 29 determines the diopter position. Based on the distance information of the subject acquired in S301, the diopter position for the images to be displayed on the right eye image display unit 14R and the left eye image display unit 14L is determined. In S303, the calculation processing unit 29 executes diopter adjustment processing. Based on the diopter position determined in S302, the right eye diopter adjustment unit 15R and the left eye diopter adjustment unit 15L perform diopter adjustment.

[0046] In S304, the calculation processing unit 29 performs a parallax determination process. Based on the distance information of the subject acquired in S301, the parallax of the images to be displayed on the right eye image display unit 14R and the left eye image display unit 14L is determined. In S305, the calculation processing unit 29 executes a display process for the parallax images. The parallax images are a pair of left and right images with different viewpoints. Based on the parallax determined in S304, the right eye image display unit 14R and the left eye image display unit 14L display the parallax images.

[0047] After S303 and S305 are completed, the process proceeds to S306. The calculation processing unit 29 determines whether the video display has been completed. If it is determined that the video display has been completed, the process of S300 is terminated. If it is determined that the video display has not been completed, the process returns to S301 and continues.

[0048] As described above, by repeatedly performing the diopter adjustment (S303) and parallax image display (S305) processes, it is possible to display an image with diopter and parallax that matches the subject distance of the displayed image. In other words, it is possible to present an image to the user that is close to the real world and does not cause discomfort.

[0049] In the image display device 30 of this embodiment, after the IPD adjustment process of S105 in Fig. 4 is performed, the diopter adjustment process of S200 is performed. This makes it possible to display an image with the correct relationship between parallax and subject distance. The problem of performing diopter adjustment before IPD adjustment will be described with reference to Fig. 8.

[0050] FIG. 8 is a schematic diagram showing a conventional image display device. The image display 1 consists of a right-eye display 1R and a left-eye display 1L. The right-eye display 1R displays a right-eye display image 1Ra, and the left-eye display 1L displays a left-eye display image 1La. Distance 7a is the distance between the right-eye display image 1Ra and the left-eye display image 1La. The eyepiece optical system 2 consists of a right-eye eyepiece optical system 2R and a left-eye eyepiece optical system 2L. Distance 8a is the distance between the right-eye eyepiece optical system 2R and the left-eye eyepiece optical system 2L. Distance 9d between the user's right eye 5R and left eye 5L corresponds to the interpupillary distance.

[0051] 8 shows a state in which IPD adjustment (S105 in FIG. 4) has not been performed, and the distance 8a between the right eye ocular optical system 2R and the left eye ocular optical system 2L is different from the interpupillary distance 9d. An example is shown in which the interpupillary distance 9d is larger than the distance 8a.

[0052] When a conventional image display device is used to display a virtual image 4a at a subject distance 11a, it is assumed that the interpupillary distance coincides with the distance 8a between the right eye ocular optical system 2R and the left eye ocular optical system 2L. In other words, the distance 7a between the right eye display image 1Ra and the left eye display image 1La is set based on this assumption.

[0053] If the distance between the right eye 5R and the left eye 5L were the same as the distance 8a between the right eye ocular optical system 2R and the left eye ocular optical system 2L, light beams would reach the user's eyes, as shown by the right eye observation light beam 6Ra and the left eye observation light beam 6La. However, in a conventional image display device, the interpupillary distance 9d is greater than the distance 8a between the right eye ocular optical system 2R and the left eye ocular optical system 2L, so the right eye observation light beam 6Ra and the left eye observation light beam 6La do not reach the user's right eye 5R and left eye 5L. The light beams that reach the user's right eye 5R and left eye 5L, respectively, are the right eye observation light beam 6Rd and the left eye observation light beam 6Ld. In this case, the user sees a virtual image 4d at a position at object distance 11d where the right eye observation light beam 6Rd and the left eye observation light beam 6Ld intersect. Therefore, the object distance 11a corresponding to the position that a conventional image display device attempts to display is different from the object distance 11d perceived by the user.

[0054] If diopter adjustment (FIG. 4: S200) is performed without IPD adjustment (FIG. 4: S105), the distance 8a between the right eye eyepiece optical system 2R and the left eye eyepiece optical system 2L will be misaligned with the interpupillary distance 9d. If diopter adjustment is performed with the distance 8a and the interpupillary distance 9d misaligned, the subject distance 11a corresponding to the position at which the image display device is intended to display and the subject distance 11d perceived by the user will be misaligned by the amount of the misalignment in the interpupillary distance. In other words, with conventional image display devices, diopter adjustment is performed while the interpupillary distance is misaligned with respect to the image display means, resulting in a problem in which the subject distance is misaligned by the amount of the misalignment in the interpupillary distance.

[0055] Next, how this embodiment solves the above problem will be described with reference to Figure 9. Figures 9(A), (B), and (C) are schematic diagrams showing images at subject distances 11a, 11a, and 11c presented to users with interpupillary distances 9a, 9b, and 9c, respectively.

[0056] In FIG. 9A, a user with an interpupillary distance of 9a observes an image at an object distance 11a. In this embodiment, IPD adjustment (FIG. 4: S105) is performed before diopter adjustment (FIG. 4: S200). Therefore, the interpupillary distance 9a coincides with the distance 8a between the right-eye eyepiece optical system 2R and the left-eye eyepiece optical system 2L. The image display device 30 displays a virtual image 4a at the object distance 11a. In this case, assuming that the interpupillary distance coincides with the distance 8a between the right-eye eyepiece optical system 2R and the left-eye eyepiece optical system 2L, the distance 7a between the right-eye display image 1Ra and the left-eye display image 1La is set. The light beams reaching the user's right eye 5R and left eye 5L are a right-eye observation light beam 6Ra and a left-eye observation light beam 6La. To the user, the virtual image 4a appears to exist at the position at the object distance 11a where the right-eye observation light beam 6Ra and the left-eye observation light beam 6La intersect. Therefore, the subject distance corresponding to the image displayed by the image display device 30 and the subject distance actually perceived by the user coincide with the distance 11a.

[0057] Next, referring to FIG. 9B, a case will be described in which a user with an interpupillary distance of 9b (>9a) observes a displayed image on the image display device 30. A user with an interpupillary distance of 9b observes an image at an object distance of 11a. In this embodiment, because the IPD adjustment (FIG. 4: S105) is performed before the diopter adjustment (FIG. 4: S200), the interpupillary distance 9b coincides with the distance 8b between the right-eye ocular optical system 2R and the left-eye ocular optical system 2L. The image display device 30 displays a virtual image 4a at the object distance 11a. In this case, assuming that the interpupillary distance coincides with the distance 8b between the right-eye ocular optical system 2R and the left-eye ocular optical system 2L, the distance 7b between the right-eye display image 1Rb and the left-eye display image 1Lb is set. The light beams reaching the user's right eye 5R and left eye 5L are a right-eye observation light beam 6Rb and a left-eye observation light beam 6Lb. To the user, the virtual image 4a appears to be at a position at subject distance 11a where the right eye observation light beam 6Rb and the left eye observation light beam 6Lb intersect. Therefore, the subject distance corresponding to the image displayed by the image display device 30 and the subject distance actually perceived by the user coincide at distance 11a.

[0058] 9(A) and 9(B), even when a user with a different interpupillary distance wears the image display device 30 on their head, the IPD adjustment is performed before the diopter adjustment, so that the user's interpupillary distance matches the distance between the right eye ocular optical system 2R and the left eye ocular optical system 2L. This makes it possible to match the subject distance of the image displayed by the image display device 30 with the subject distance actually perceived by the user.

[0059] Referring to FIG. 9C, a case will be described in which a user with an interpupillary distance of 9c views an image at an object distance 11c using the image display device 30. In this embodiment, since the IPD adjustment is performed before the diopter adjustment, the interpupillary distance 9c coincides with the distance 8c between the right-eye eyepiece optical system 2R and the left-eye eyepiece optical system 2L. The image display device 30 displays a virtual image 4c at the object distance 11c. In this case, assuming that the interpupillary distance coincides with the distance 8c between the right-eye eyepiece optical system 2R and the left-eye eyepiece optical system 2L, a distance 7c between the right-eye display image 1Rc and the left-eye display image 1Lc is set. The light beams reaching the user's right eye 5R and left eye 5L are a right-eye observation light beam 6Rc and a left-eye observation light beam 6Lc. To the user, the virtual image 4c appears to exist at the position at the object distance 11c where the right-eye observation light beam 6Rc and the left-eye observation light beam 6Lc intersect. Therefore, the subject distance corresponding to the image displayed by the image display device 30 and the subject distance actually perceived by the user match at distance 11c. Even if the subject distance of the displayed image is changed in this way, the subject distance corresponding to the image displayed by the image display device 30 and the subject distance actually perceived by the user can be made to match. In other words, because the IPD adjustment is performed before the diopter adjustment, the interpupillary distance and the distance between the right eye ocular optical system 2R and the left eye ocular optical system 2L match.

[0060] Next, the frequency of adjustments performed by the interpupillary distance adjustment unit 33, the right eye diopter adjustment unit 15R, and the left eye diopter adjustment unit 15L will be described. When wearing of the image display device 30 is detected in the wearing detection (FIG. 4: S101), the interpupillary distance adjustment unit 33 performs IPD adjustment (FIG. 4: S105).

[0061] On the other hand, the right-eye diopter adjustment unit 15R and the left-eye diopter adjustment unit 15L are constantly performing diopter adjustment (S303) while an image is being displayed in FIG. 7. In other words, the right-eye diopter adjustment unit 15R and the left-eye diopter adjustment unit 15L are adjusted, i.e., driven, more frequently than the interpupillary distance adjustment unit 33. In the image display device 30, as described in FIG. 2, the right-eye diopter adjustment unit 15R performs adjustment by moving only the right-eye display unit 1R and the display unit holding member 13R. On the other hand, the interpupillary distance adjustment unit 33 must drive (move) the right-eye image display unit 14R and the right-eye diopter adjustment unit 15R as a set. Therefore, the weight of the movable parts is lighter for adjustment by the right-eye diopter adjustment unit 15R than for interpupillary distance adjustment.

[0062] Similarly, on the left eye side, the left eye diopter adjustment unit 15L adjusts by moving only the left eye display 1L and the display unit holding member 13L. Meanwhile, the interpupillary distance adjustment unit 33 must drive (move) the left eye image display unit 14L and the left eye diopter adjustment unit 15L as a set. Therefore, the weight of the moving parts for adjustment using the left eye diopter adjustment unit 15L is lighter than that for interpupillary distance adjustment. By arranging the image display means and diopter adjustment means in the moving parts of the interpupillary distance adjustment unit, the weight of the moving parts of the diopter adjustment means, which is used frequently, can be reduced, and a configuration that allows for efficient driving can be realized.

[0063] According to this embodiment, it is possible to realize an image display device that can prevent deviations in the subject distance of an image when an image is displayed, which would occur if diopter adjustment were performed while the interpupillary distance remained misaligned with respect to the image display means.

[0064] [Second embodiment] Next, a second embodiment will be described with reference to Fig. 10. This embodiment differs from the first embodiment in the position of the interpupillary distance adjustment unit 33. In the first embodiment, the interpupillary distance adjustment unit 33 is disposed adjacent to the right eye image display unit 14R and the left eye image display unit 14L in the +Z direction.

[0065] In contrast, in this embodiment, the interpupillary distance adjustment unit 33 is arranged adjacent to the right eye image display unit 14R and the left eye image display unit 14L in the +Y direction. This has the advantage of making it possible to reduce the size of the image display device 30 in the Z axis direction compared to the first embodiment. In this embodiment, the same components as those in the first embodiment will be designated by the same reference numerals as those in the first embodiment, and detailed descriptions of these components will be omitted, and only differences from the first embodiment will be described. This method of omitting descriptions will be the same in the embodiments described below.

[0066] Figure 10 is a diagram illustrating the configuration of an image display device 30 according to this embodiment. Figure 10(A) is a schematic diagram of the image display device 30 as viewed from the +Y direction, and Figure 10(B) is a schematic diagram of the image display device 30 as viewed from the -Z direction. Figure 10(C) is a schematic diagram of the image display device 30 as viewed from the +X direction.

[0067] In the first embodiment, as described in Fig. 2(A), the interpupillary distance adjustment unit 33 is disposed at a position adjacent to the right eye image display unit 14R and the left eye image display unit 14L in the +Z direction. In contrast, as shown in Fig. 10(A), in this embodiment, the interpupillary distance adjustment unit 33 is not disposed at a position adjacent to the right eye image display unit 14R and the left eye image display unit 14L in the +Z direction in the image display device 30. In other words, the image display device 30 can be made smaller in size in the Z axis direction accordingly.

[0068] The example in Figure 10 shows a system in which only images in a virtual space are displayed on the right-eye display 1R and the left-eye display 1L. An MR (Mixed Reality) device is equipped with a pair of cameras for capturing real-world images and displays a composite image of the real world and a virtual space. In this case, if the positions of the pair of cameras and the user's eyes are significantly different, parallax and size may differ significantly. If the perceived distance between the image captured by the pair of cameras and the real world actually seen by the user's eyes differs significantly, the user may feel uncomfortable viewing the composite image of the virtual and real world images. To achieve a composite image with minimal discomfort using an MR device, it is necessary to minimize the perceived distance between the real-world image captured by the pair of cameras and the real-world image seen by the user's eyes. To achieve this, it is best to position the pair of cameras as close as possible to the user's eyes. Another advantage of minimizing the size of the image display device 30 in the Z-axis direction is that when this technology is applied to an MR device, it is easier to position the cameras as close as possible to the user's eyes. According to this embodiment, the sense of distance between the real-world image captured using a pair of cameras and the real-world image seen by the user's both eyes can be reduced, thereby realizing a mixed reality image that feels less strange.

[0069] In Figure 10(B), the motors 21R, 21L, lead screws 22R, 22L, and racks 23R, 23L that constitute the interpupillary distance adjustment unit 33 are arranged in adjacent positions in the +Y direction of the right eye image display unit 14R and the left eye image display unit 14L.

[0070] Rotation of a motor 21R fixed to the fixing member 20 rotates a lead screw 22R, and the right-eye image display unit 14R fixed to the rack 23R is configured to be movable in the X-axis direction. The right-eye image display unit 14R also includes a guided portion 25R. The guided portion 25R engages with a guide shaft 24R fixed to the fixing member 20, thereby forming a guide mechanism in the X-axis direction. This allows the right-eye image display unit 14R to be moved linearly in the X-axis direction by the motor 21R.

[0071] The right-eye image display unit 14R and the right-eye diopter adjustment unit 15R are coupled together, so that the right-eye image display unit 14R and the right-eye diopter adjustment unit 15R can be moved together in the X-axis direction by driving the motor 21R. In this embodiment, as in the first embodiment, the drive method for each motor is not limited.

[0072] Regarding the left eye side mechanism for adjusting the interpupillary distance, detailed explanation will be omitted since it is sufficient to replace the symbol R added to the reference numerals in the above explanation with the symbol L and read the right eye as the left eye.

[0073] In addition to the effects of the first embodiment, this embodiment has the effect of contributing to the miniaturization of the image display device 30 in the Z-axis direction.

[0074] [Third embodiment] The third embodiment will be described with reference to FIG. 11. The difference between this embodiment and the second embodiment is that the positions of the vibrator 18R and the friction member 19R are swapped in the X-axis direction. In the second embodiment (see FIG. 10), the vibrator 18R is disposed on a first side closer to the right-eye image display unit 14R, and the friction member 19R is disposed on a second side farther from the right-eye image display unit 14R. In contrast, in this embodiment, the friction member 19R is disposed on the first side, and the vibrator 18R is disposed on the second side. This configuration allows the vibrator 18R, whose characteristics change significantly with temperature compared to the second embodiment, to be located farther away from the right-eye display unit 1R, which is a heat source. Even during prolonged use, the characteristics of the vibrator 18R are less likely to change due to heat from the right-eye display unit 1R, enabling more stable diopter adjustment. Other differences will be described in detail with reference to FIG. 11. In this embodiment, the same components as those in the second embodiment are designated by the same reference numerals already used, and detailed descriptions of these components will be omitted.

[0075] 11(A) is a diagram of the image display device 30 of this embodiment when viewed from the +Y direction. FIG. 11(B) is a diagram of the image display device 30 of this embodiment when viewed from the -Z direction. The right-eye diopter adjustment unit 15R includes a vibrator holding member 16R, a guide shaft 17R, a vibrator 18R, and a friction member 19R. In the second embodiment, the vibrator holding member 16R is guided by the guide shaft 17R, thereby being movable in the Z-axis direction. In this embodiment, the friction member 19R is guided by the guide shaft 17R, thereby being movable in the Z-axis direction.

[0076] The vibrator holding member 16R, the guide shaft 17R, the vibrator 18R, and the friction member 19R constitute a diopter adjusting section for the right eye 15R. The vibrator 18R and the vibrator 18L constitute a first driving means.

[0077] The friction member 19R has a protrusion on the first side, and the display holding member 13R has a V-shaped groove corresponding to the protrusion. The protrusion of the friction member 19R engages with the V-shaped groove of the display holding member 13R, and the friction member 19R and the display holding member 13R move together in the Z-axis direction. This allows the right-eye diopter adjustment unit 15R to have a diopter adjustment function for the right-eye image display unit 14R. For example, when the diopter of the right-eye image display unit 14R is changed toward infinity, the right-eye display unit 1R moves in the +Z direction, and when it is changed toward close range, the right-eye display unit 1R moves in the -Z direction.

[0078] In the right-eye diopter adjustment unit 15R, the vibrator 18R is composed of a piezoelectric element, and therefore its characteristics change relatively greatly with temperature. On the other hand, the friction member 19R is made of metal, and therefore its characteristics change relatively little with temperature. The right-eye display 1R is a component whose temperature rises depending on the amount of heat generated. Assume that the vibrator 18R, whose characteristics change significantly with temperature, is located near a heat source. In this case, the drive characteristics of the right-eye diopter adjustment unit 15R may change over time. Therefore, in this embodiment, the friction member 19R is located near the right-eye display 1R, which is the heat source, in the X-axis direction, and the vibrator 18R is located far from the right-eye display 1R. This makes it possible to prevent changes in the drive characteristics of the right-eye diopter adjustment unit 15R, even over long periods of use.

[0079] In the image display device 30, the right-eye image display unit 14R and the right-eye diopter adjustment unit 15R are disposed adjacent to each other in the X-axis direction. The size relationship between the right-eye image display unit 14R and the right-eye diopter adjustment unit 15R is the same as in the above-described embodiment. In order to reduce the size of the image display device 30, the right-eye diopter adjustment unit 15R needs to be made smaller in the X-axis direction than in the Y-axis direction.

[0080] In the right-eye diopter adjustment unit 15R, when a driving force is generated to the friction member 19R by a high-frequency elliptical motion generated at the contact portion between the vibrator 18R and the friction member 19R, it is necessary to press and urge the vibrator 18R against the friction member 19R. For this reason, as shown in FIG. 11(B), the right-eye diopter adjustment unit 15R includes a pressing member 42R. For example, the pressing member 42R has a urging member such as an elastic body. The pressing members 42R are disposed adjacent to both sides in the Y-axis direction of the vibrator holding member 16R. When viewed from the Y-axis direction, the pressing members 42R are disposed so as to overlap with the vibrator 18R in the X-axis direction. This allows the right-eye diopter adjustment unit 15R to be made thinner in the X-axis direction.

[0081] The friction member 19R is disposed so that the normal direction of the friction surface 19R-a is parallel to the X-axis direction. With this arrangement, the direction in which the right-eye diopter adjustment unit 15R is thinnest is the X-axis direction, which contributes to the miniaturization of the image display device 30.

[0082] In this embodiment, a connecting member 13R-a that connects the right-eye display 1R and the right-eye diopter adjustment unit 15R and an opening 44R for passing through the connecting member 13R-a are provided. The opening 44R is formed on a side surface of the right-eye image display unit 14R in the +X direction. The vibrator 18R contacts the friction surface 19R-a of the friction member 19R at the contact portion 18R-a. During use, the opening 44R is positioned vertically above (in the +Y direction) the contact portion 18R-a in the Y-axis direction. By providing the opening 44R vertically above the contact portion 18R-a, wear debris generated at the contact portion 18R-a during use can be prevented from entering the interior of the right-eye image display unit 14R.

[0083] In the drive mechanism for diopter adjustment (right eye), the driven part is the display device 1R for the right eye, and the movable part is the friction member 19R. A connecting member 13R-a provided on the display device holding member 13R connects the display device 1R for the right eye and the friction member 19R. The connecting member 13R-a transmits the driving force generated between the vibrator 18R and the friction member 19R to the display device 1R for the right eye, and plays a role in moving the friction member 19R and the display device 1R for the right eye together in the Z-axis direction.

[0084] The right-eye image display unit 14R is surrounded by a cover to prevent dust and other particles from entering the interior, and has an opening 44R formed therein corresponding to the location through which the connecting member 13R-a passes. The contact portion 18R-a of the vibrator 18R and the friction member 19R move relative to each other while sliding, and wear debris generated at the contact portion 18R-a may pass through the opening 44R and reach the right-eye display unit 1R. Measures are needed to prevent the wear debris from affecting the display screen of the right-eye display unit 1R, thereby significantly reducing image quality.

[0085] In this embodiment, the opening 44R is positioned vertically above (in the +Y direction) the contact portion 18R-a by a distance D. This prevents wear debris generated at the contact portion 18R-a during use from passing through the opening 44R and reaching the right-eye display device 1R, making it possible to provide a high-quality display image.

[0086] Furthermore, wear debris generated by sliding between the vibrator 18R and the friction member 19R occurs only when the user is wearing the image display device 30 and viewing an image. Therefore, in this embodiment, an adhesive member 45R is disposed at a predetermined position vertically downward (in the -Y direction) from the contact portion 18R-a. The adhesive member 45R has an adhesive surface. Wear debris generated at the contact portion 18R-a during use falls vertically downward (in the -Y direction) from the contact portion 18R-a due to gravity and is adsorbed by the adhesive member 45R. By disposing the adhesive member 45R vertically downward from the contact portion 18R-a during use, the adhesive member 45R adsorbs the fallen wear debris while the user is wearing the image display device 30 and viewing an image. The adhesive member 45R can adsorb the wear debris before it diffuses into the right-eye diopter adjustment portion 15R.

[0087] As described above, wear debris is adsorbed by the adhesive member 45R while the user is wearing the image display device 30 and watching an image. For example, assume that the image display device 30 assumes a position different from the position shown in Fig. 11(B) after the user watches an image. In this case, even if the position of the opening 44R is not vertically above the contact portion 18R-a, the adhesive member 45R has already adsorbed the wear debris, and therefore, it is possible to prevent the wear debris from entering the inside of the right-eye image display unit 14R through the opening 44R.

[0088] In the image display device of the above embodiment, by adjusting the interpupillary distance and then adjusting the diopter, the interpupillary distance and the distance between the left and right eyepiece optical systems can be made to match. This allows the subject distance of the image displayed by the image display device to match the subject distance actually perceived by the user. Therefore, an image display device can be realized that can prevent deviations in the subject distance of the image from occurring when diopter adjustment is performed while the interpupillary distance remains misaligned with respect to the image display means.

[0089] In the above embodiment, an example of a drive mechanism for moving the display when changing the distance between the display and the eyepiece optical system is shown, but the present invention is not limited to this and can be applied to an embodiment having a drive mechanism for moving the eyepiece optical system or a drive mechanism for moving both the display and the eyepiece optical system.

[0090] [Other embodiments] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions. [Explanation of symbols]

[0091] 1R,1L Right eye display, left eye display 2R,2L Eyepiece optical system for right eye, eyepiece optical system for left eye 14R,14L Right eye image display section, left eye image display section 15R,15L Diopter adjustment section for right eye, diopter adjustment section for left eye 27R, 27L Interpupillary distance detection unit 29 Processing unit 30 Video display device 33 Interpupillary distance adjustment section

Claims

1. A plurality of image display means each having a display and a display optical system; a first adjustment means for changing an optical positional relationship between the display and the display optical system; a second adjustment means for changing the interval between the plurality of image display means; After the second adjustment means changes the intervals between the plurality of image display means, the first adjustment means changes the optical positional relationship between the display devices and the display optical system.

13. A video display device comprising:

2. A detection means for detecting a pupillary distance of a user is provided, the first adjustment means performs visibility adjustment for the image display means by changing an optical positional relationship between the display device and the display optical system; the second adjustment means performs an adjustment corresponding to the interpupillary distance by changing an interval between the plurality of image display means in accordance with a detection result of the detection means; The second adjustment means performs an adjustment corresponding to the interpupillary distance, and then the first adjustment means performs a diopter adjustment.

2. The image display device according to claim 1.

3. a first image display means including a first display and a first display optical system; a second image display means including a second display and a second display optical system; a first driving means for changing a distance between the first display and the first display optical system and a distance between the second display and the second display optical system; a second driving means for changing a distance between the first image display means and the second image display means, The first adjustment means adjusts the diopter by the first driving means, The second adjustment means performs an adjustment corresponding to the interpupillary distance by the second driving means.

3. The image display device according to claim 2.

4. a first image display means including a first display and a first display optical system; a second image display means including a second display and a second display optical system; The first adjustment means is composed of an adjustment means for adjusting the visibility of the first image display means and an adjustment means for adjusting the visibility of the second image display means.

3. The image display device according to claim 2.

5. The second adjustment means adjusts the distance between the first image display means and the second image display means by integrally moving the first and second image display means and the first adjustment means.

5. The image display device according to claim 3 or 4.

6. The second adjustment means performs the adjustment after the first adjustment means changes the diopter toward the infinity direction.

6. The image display device according to claim 2, wherein the first and second electrodes are arranged in a first direction.

7. The first adjustment means changes the diopter in the infinity direction and then in the close distance direction, adjusting the distance between the display and the display optical system to a distance corresponding to the selected position.

7. The image display device according to claim 6.

8. The second adjustment means is disposed relative to the image display means in a direction perpendicular to the optical axis direction and in a direction in which the image display means is movable.

8. The image display device according to claim 2, wherein the first and second electrodes are arranged in a first direction.

9. a first image display means having a first display and a first display optical system, and a second image display means having a second display and a second display optical system; a first adjustment means for adjusting visibility of the first and second image display means by changing an optical positional relationship between the first display and the first display optical system and an optical positional relationship between the second display and the second display optical system; A detection means for detecting a user's interpupillary distance; a second adjustment means for adjusting the distance between the first image display means and the second image display means in accordance with a detection result of the detection means, a first direction is a direction in which the first and second display optical systems are arranged, and a second direction is a direction perpendicular to the first direction and the optical axis direction of the display optical system, the first adjustment means is disposed on a side away from the optical axis of the first and second display optical systems in the first direction, and the second adjustment means is disposed on a side vertically upward in use in the second direction, The second adjustment means performs an adjustment corresponding to the interpupillary distance, and then the first adjustment means performs a diopter adjustment.

13. A video display device comprising:

10. The first adjustment means includes a driving means for changing the distance between the display and the display optical system by using a driving source that generates a thrust by vibration.

10. The image display device according to claim 9.

11. The driving means is a vibration member that generates vibration at a contact portion; a friction member having a friction surface that comes into contact with the contact portion; a pressing means for pressing the contact portion against the friction surface, The vibration member and the friction member move relative to each other due to vibration generated at the contact portion.

11. The image display device according to claim 10.

12. The friction surface is a surface whose normal direction is parallel to the first direction.

12. The image display device according to claim 11.

13. When viewed from the second direction, the pressing means and the vibration member are arranged to overlap in the first direction.

13. The image display device according to claim 11 or 12.

14. a driven portion that moves in the optical axis direction of the display optical system; a movable part that moves due to vibration generated at the contact part; A connecting member that connects the movable portion and the driven portion; an opening provided on a surface of the image display means adjacent to the driving means, through which the connecting member passes; 14. The image display device according to claim 11,

15. When in use, the opening is located vertically above the contact portion.

15. The image display device according to claim 14.

16. The friction member is disposed closer to the image display means than the vibration member in the first direction.

16. The image display device according to claim 11,

17. The movable portion includes the friction member.

15. The image display device according to claim 14.

18. The display unit moves in the optical axis direction of the display optical system in accordance with the movement of the driven portion.

15. The image display device according to claim 14.

19. The driving means has an adhesive member, In use, the adhesive member is disposed vertically below the contact portion.

19. The image display device according to claim 11,

20. The detection means detects the interpupillary distance from image information obtained by photographing the user's eyes from an oblique direction relative to the optical axis of the image display means.

20. The image display device according to claim 2, wherein the first and second electrodes are arranged in a first direction.

21. The image display means displays an image having parallax.

21. The image display device according to claim 1,

22. Can be worn on the user's head 22. The image display device according to claim 1,

23. A control method executed in an image display device that displays images using a plurality of image display means each having a display device and a display optical system, comprising: a first step of changing an interval between the plurality of image display means; and a second step of changing an optical positional relationship between the display and the display optical system after the first step.

23. A method for controlling a video display device comprising the steps of:

24. The steps according to claim 23 are executed by a computer of a video display device. A program characterized by:

Images