Image display device

Abstract

To provide an image display device that can suppress influence of interference of a laser beam on image degradation while suppressing the cost of running.SOLUTION: An image display device 10 includes: a laser light source 11 set in a first site (a floor 91) of a mobile body; an optical fiber 12 having an end (a first end part 121) arranged in a position where a laser beam from the laser light source 11 enters; an image display element 14 between another end (a second end part 122) of the optical fiber 12 and a display surface (a half mirror 15); and a middle vibration unit 13 for fixing a second site (a side wall 92) of the mobile body, which is different from the first site of the mobile body, and the middle part of the optical fiber 12 to each other.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an image display device, and more particularly to an image display device that displays image information in front of a user's eyes, such as a head mounted display (HMD: Head Mounted Display, also known as a helmet mounted display) or a head-up display (HUD: Head-Up Display). [Background technology]

[0002] In rotorcraft and aircraft, HMDs are used that display image information in front of the pilot's eyes by projecting an image onto a projection target such as a visor provided on a helmet worn by the pilot (user) on the head, or goggles or glasses worn by the pilot in front of the pilot's eyes. Examples of such HMDs include an HMD having a light source, a display element made of a transmissive liquid crystal panel fixed to the helmet, and an optical fiber arranged to receive light emitted from the light source at one end and irradiate the light from the other end onto the back of the display element. According to this configuration, the light emitted from the light source is irradiated onto the back of the display element through the optical fiber, and the light that has passed through the display element is projected onto the projection target, thereby displaying image information. By using optical fibers in this way, the light source can be provided outside the wearable object such as a helmet worn by the pilot, and the weight of the head-mounted portion of the image display device can be reduced.

[0003] A laser light source is generally used as the light source. A laser light source is superior to other light sources such as an LED (light emitting diode) in that the wavelength shift of the light (laser light) it generates is small and that light can be efficiently introduced from the light source into an optical fiber.

[0004] However, when a laser light source and an optical fiber are used, a problem occurs in that the light that has passed through the optical fiber is irradiated onto the display element in a state in which a spot-like interference pattern (speckle) is generated due to interference, and the speckle is superimposed on the image projected onto the projection target. Such speckle is generated when light of multiple propagation modes that has passed through the optical fiber interferes with each other due to their phase difference (see Patent Document 1).

[0005] Therefore, Patent Document 1 describes that an image display device is provided with a vibration generator that applies vibration to an optical fiber. This causes the position of the optical fiber to fluctuate, which in turn changes the weighting of each propagation mode, causing fluctuations in speckle. If the speckle fluctuates at a frequency too high for a human to perceive, the HMD user cannot perceive the speckle in the image projected onto the projection target after the laser light passes through the optical fiber and the display element, and thus the problem caused by the speckle can be avoided. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent Publication No. 2010 / 0053729 Summary of the Invention [Problem to be solved by the invention]

[0007] When a vibration generator such as that described in Patent Document 1 is used, power is required to operate the vibration generator, which increases running costs.

[0008] So far, the case where the pilot of a rotorcraft or an aircraft uses the image display device has been described as an example, but the same problem occurs when the pilot of a moving body that moves with people on board other than the rotorcraft or aircraft, such as an automobile or a railroad vehicle, or when a person (such as a passenger) other than the pilot on board a moving body (including rotorcraft and aircraft, as well as other things) uses the image display device. In addition, in the above example, the HMD that projects an image onto an attachment such as a helmet worn by the pilot has been described as an example, but the same problem occurs with image display devices such as HUDs that display image information in front of the user's eyes by projecting an image onto an object to be projected other than such attachment, such as the windshield of a rotorcraft or an aircraft or the windshield of an automobile.

[0009] An object of the present invention is to provide an image display device capable of suppressing the influence of laser light interference on image degradation while suppressing running costs. [Means for solving the problem]

[0010] A moving body according to the present invention, which has been made to solve the above problems. mounted image display device Place , A laser light source installed in a first portion of the moving object; an optical fiber having one end disposed at a position where the laser light emitted from the laser light source is incident; an image display element disposed between the other end of the optical fiber and a display surface; A second portion of the movable body, which is different from the first portion, is fixed to an intermediate portion of the optical fiber. Fixed part and Equipped with. Effect of the Invention

[0014] The present invention Mobile mountedIn an image display device for mobile phones, the optical fiber vibrates in the same way as a first portion of the moving object at the end (the one end) on the light source side, and in the same way as a second portion at the middle portion. Since the first portion and the second portion are different portions of the moving object, they vibrate differently when the moving object moves. In this way, since the optical fiber vibrates differently at the end and middle portion, the shape (curvature) of the optical fiber fluctuates, and the weighting of each propagation mode of the laser light propagating within the optical fiber changes. This causes fluctuations in the speckles, and the movement of the moving object mounted Therefore, the user of the image display device will be unable to perceive the speckles. The present invention Mobile mounted According to the image display device for use, since no power is required for applying vibration to the intermediate portion, it is possible to reduce running costs and to suppress the influence of laser light interference on image degradation. [Brief description of the drawings]

[0017] [Figure 1] 1 is a schematic configuration diagram showing a first embodiment of an image display device to be mounted on a moving body according to the present invention. [Figure 2A] A photograph of the image of laser light emitted from an optical fiber when no vibration is being generated in the optical fiber. [Figure 2B] A photograph of the image of laser light emitted from an optical fiber when vibrations are being generated in the optical fiber. [Diagram 3] FIG. 5 is a schematic configuration diagram showing a second embodiment of the image display device to be mounted on a moving body according to the present invention. [Figure 4] FIG. 11 is a schematic configuration diagram showing a modified example of the image display device to be mounted on a moving body according to the second embodiment. [Diagram 5] FIG. 11 is a schematic configuration diagram showing a third embodiment of the image display device to be mounted on a moving body according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] 1 to 5, a moving body according to the present invention will be described. mounted An embodiment of an image display device for use (hereinafter, abbreviated as "image display device") will be described.

[0019] (1) First embodiment (1-1) Configuration of the image display device according to the first embodiment 1 shows a schematic configuration of an image display device 10 according to the first embodiment. The image display device 10 includes a laser light source 11, an optical fiber 12, an intermediate vibration unit 13, an image display element 14, and a half mirror 15.

[0020] The laser light source 11 is housed in a housing 111, and the housing 111 is placed on the floor 91 (corresponding to the first portion) of the moving body. In addition to the laser light source 11, the housing 111 also houses two lenses 112 and 113 that introduce the laser light from the laser light source 11 to one end (referred to as the "first end 121") of the optical fiber 12. The housing 111 is provided with a hole into which a portion of the optical fiber 12 near the first end 121 is inserted, and the optical fiber 12 inserted into the hole is fixed to the housing 111 so that the first end 121 is positioned opposite the lens 113.

[0021] In this embodiment, a multimode fiber is used as the optical fiber 12. In addition to multimode fibers, single-mode fibers are also available as optical fibers, but multimode fibers are superior in that they have a larger core diameter and can transmit a larger amount of light. On the other hand, multimode fibers propagate light of multiple propagation modes, and therefore were the main cause of speckles in conventional image display devices.

[0022] The fixed portion 123 in the middle of the optical fiber 12 is fixed to the side wall 92 (corresponding to the second portion) of the moving body by affixing it with an adhesive. When this adhesive has solidified, it becomes the intermediate excitation portion 13. The intermediate excitation portion 13 transmits vibrations generated in the side wall 92 to the fixed portion 123 of the optical fiber 12, and vibrates the fixed portion 123. Note that a fixing member other than the solidified adhesive, such as a metal fitting, may be used as the intermediate excitation portion 13.

[0023] The image display element 14 is made of a transmissive liquid crystal panel, and is provided on the optical path of the light emitted from the other end (hereinafter referred to as the "second end 122") of the optical fiber 12. Between the second end 122 and the image display element 14, a lens 141 that converts the light emitted from the optical fiber 12 into parallel light, and a diffusion plate 142 that diffuses (scatters) the light that has passed through the lens 141 are disposed. A signal line 143 is connected to the image display element 14 for receiving an image signal for displaying an image from an image display processing device (not shown).

[0024] The half mirror 15 allows the user to view the image displayed on the image display element 14 as a virtual image by projecting light that has passed through the transmissive liquid crystal panel of the image display element 14. In this embodiment, the half mirror 15 is a substantially transparent visor provided on a helmet worn by a user (operator of a moving body). The user views an image obtained by superimposing the image displayed on the image display element 14 as a virtual image on an image seen in a normal field of vision through the half mirror 15. It is also possible to use an opaque mirror instead of the half mirror 15, and further provide a camera that captures an image corresponding to the user's normal field of vision in the image display device 10, and display an image obtained by superimposing an image captured by the camera and an image based on an image signal supplied from an image display processing device on the image display element 14, and project the image on the mirror, thereby allowing the user to view the superimposed image as a virtual image. A display optical system 151 that introduces light from the image display element 14 to the half mirror 15 is provided between the image display element 14 and the half mirror 15.

[0025] The second end 122 of the optical fiber 12, the lens 141, the diffuser 142, the image display element 14 and the display optical system 151, as well as the aforementioned half mirror 15 (each of the components shown surrounded by a dashed line in FIG. 1) are fixed to the helmet.

[0026] Of the optical fiber 12, parts other than the first end 121, the fixed part 123, and the second end 122 described above are not fixed to other objects, and when vibrations are applied from the outside, these parts vibrate and deform in response to the vibrations.

[0027] (1-2) Operation of the Image Display Device of the First Embodiment The operation of the image display device 10 of the first embodiment will be described below. Before operating the image display device 10, the user puts the helmet on his / her head. The user views the outside through the visor (half mirror 15).

[0028] The image display device 10 is used when a moving object is moving. The image display element 14 displays an image on a transmissive liquid crystal panel based on an image signal transmitted from an image display processing device through a signal line 143. At the same time, the laser light source 11 emits a laser beam. The laser beam passes through the lenses 112 and 113, enters the optical fiber 12 from the first end 121, propagates through the optical fiber 12, and then exits from the second end 122, passes through the lens 141 and the diffusion plate 142, and enters the image display element 14. The laser beam then passes through the transmissive liquid crystal panel of the image display element 14 and is reflected by the half mirror 15. This allows the user to view the image displayed on the image display element 14 as a virtual image.

[0029] When the moving body is moving, vibrations are generated in the floor 91 and side wall 92 of the moving body due to vibrations generated by the power source (engine, etc.) of the moving body, vibrations due to air resistance received from the outside of the moving body, or vibrations received from the road surface in the case of an automobile. The vibrations of the floor 91 are transmitted to the first end 121 of the optical fiber 12 via the housing 111. Meanwhile, the vibrations of the side wall 92 are transmitted to the fixed part 123 in the middle part of the optical fiber 12 by the intermediate excitation part 13. Here, since the floor 91 and the side wall 92 are made of different materials and have different thicknesses, they vibrate with different amplitudes, periods, and / or phases. Therefore, the first end 121 and the fixed part 123 vibrate with different amplitudes, periods, and / or phases. This causes the shape (curvature) of the optical fiber 12 to fluctuate, and the weighting of each propagation mode of the laser light propagating through the optical fiber 12 to change. This causes fluctuations in the speckles, making it impossible for the user of the image display device 10 to perceive the speckles in the image.

[0030] According to the image display device 10 of the first embodiment, the vibration generated in the moving body is transmitted to the middle part of the optical fiber 12 by the intermediate vibration unit 13, thereby vibrating the optical fiber 12. Therefore, no power is required to vibrate the optical fiber 12, and it is possible to reduce the impact of image degradation due to interference of laser light while keeping running costs low.

[0031] Next, the results of observing the laser light emitted from the optical fiber 12 are shown for each of the cases where vibration is not generated in the optical fiber 12 and where vibration is generated. In this experiment, the image of the laser light emitted from the second end 122 projected onto a screen (not a component of the image display device 10, but provided opposite the second end 122 for this experiment) was photographed by a camera. Instead of vibration actually generated on the side wall 92 of the moving body, the optical fiber 12 was given a vibration by fixing both ends of the optical fiber 12 and slightly loosening it, and rotating the entire optical fiber 12 so that the middle part of the optical fiber 12 rotates around a straight line connecting the both ends (like a jump rope). The rotation radius of the optical fiber 12 was 6 mm at the maximum position, and the rotation frequency was 2 Hz or less. The exposure time of the camera was 0.033 seconds (period 60 Hz), which corresponds to the period in which a person can recognize a change. Note that the floor 91 of a moving body usually requires strength to support a heavy object, and is therefore made of a material that is less likely to vibrate than the side wall 92. Therefore, in this experiment, the vibration of the first end 121 caused by the vibration of the floor 91 was ignored as it was sufficiently smaller than the vibration of the fixed part 123 caused by the vibration of the side wall 92, and was not applied to the first end 121.

[0032] Photographs of the image projected on the screen are shown in Fig. 2A when no vibration is applied to the optical fiber 12, and in Fig. 2B when vibration is applied to the optical fiber 12. When no vibration is applied to the optical fiber 12, black spots are seen in the image, whereas when vibration is applied to the optical fiber 12, such spots are hardly seen. Therefore, according to the image display device 10 of the first embodiment, vibration is generated in the fixed part 123 based on the vibration of the side wall 92 of the moving body having the same frequency and amplitude as the vibration applied to the optical fiber 12 in this experiment, so that an image without the influence of speckles can be displayed.

[0033] (2) Image display device according to the second embodiment (2-1) Configuration of the image display device according to the second embodiment 3 shows a schematic configuration of an image display device 20 of the second embodiment. This image display device 20 has a laser light source 11, an optical fiber 12, a power generation unit 231, an intermediate vibration unit 232, a rechargeable battery 233, an image display element 14, and a half mirror 15. The configurations of the laser light source 11, the optical fiber 12, the image display element 14, and the half mirror 15 are similar to those in the image display device 10 of the first embodiment, and therefore detailed description thereof will be omitted.

[0034] The power generating unit 231 and the rechargeable battery 233, and the rechargeable battery 233 and the intermediate vibration unit 232 are electrically connected to each other. The power generating unit 231 is fixed to the side wall 92 of the moving body, and has a piezoelectric conversion element that converts mechanical vibrations received from the side wall 92 into AC power. The rechargeable battery 233 is charged with the power generated by the power generating unit 231. The intermediate vibration unit 232 is fixed to the fixed unit 223 at the middle part of the optical fiber 12, and has a power conversion unit that converts DC power supplied from the rechargeable battery 233 into AC power having a predetermined frequency, and a piezoelectric conversion element that converts the AC power into mechanical vibration. This predetermined frequency is set to a high value such that when vibrations of the same frequency are applied to the optical fiber 12, a person cannot see the speckles. The fixed unit 223 of the optical fiber 12 is vibrated by the mechanical vibration of the piezoelectric conversion element of the intermediate vibration unit 232.

[0035] It is also possible to omit the rechargeable battery 233 and directly electrically connect the power generation unit 231 and the intermediate vibration unit 232. In this case, the piezoelectric conversion element of the intermediate vibration unit 232 is mechanically vibrated by the electric power generated by the power generation unit 231.

[0036] (2-2) Operation of the image display device according to the second embodiment The operation of the image display device 20 of the second embodiment will be described. The image display device 20 is used when a moving object is moving. As with the image display device 10 of the first embodiment, an image is displayed on the transmissive liquid crystal panel of the image display element 14, and laser light is emitted from the laser light source 11, so that the image displayed on the transmissive liquid crystal panel is reflected by the screen 15. This allows the image displayed on the image display element 14 to be visually recognized as a virtual image by the user.

[0037] Vibrations occurring on the floor 91 when the moving body moves are transmitted to the first end 121 of the optical fiber 12 via the housing 111. On the other hand, vibrations of the side wall 92 are converted into electricity by the power generation unit 231, and vibrations are applied to the fixed part 223 located in the middle of the optical fiber 12 by the middle vibration unit 232 that operates with this electricity (which is charged in a rechargeable battery 233 and supplied from the rechargeable battery 233 in this embodiment). As a result, the first end 121 and the fixed part 223 Since the laser beams vibrate with different amplitudes, periods, and / or phases, the shape (curvature) of the optical fiber 12 fluctuates, and the weighting of each propagation mode of the laser beam propagating through the optical fiber 12 changes. As a result, the speckle also fluctuates, and the image display device 20 The user will not be able to see the speckles.

[0038] According to the image display device 20 of the second embodiment, like the image display device 10 of the first embodiment, no power is required to vibrate the optical fiber 12, and it is possible to reduce the impact of laser light interference on image degradation while keeping running costs low.

[0039] Furthermore, when the rechargeable battery 233 is provided, the power converted by the power generating unit 231 is temporarily charged in the rechargeable battery 233 and then supplied to the intermediate vibration unit 232, so that stable power can be supplied to the intermediate vibration unit 232 and the intermediate portion of the optical fiber 12 can be vibrated with stable amplitude and frequency. This makes it possible to more reliably suppress the influence of laser light interference on image degradation.

[0040] (3) Image display device according to a modification of the second embodiment 4 shows a schematic configuration of an image display device 30 according to a modified example of the second embodiment. 30 has an intermediate excitation unit (torsional vibration excitation unit) 332 as described below, instead of the intermediate excitation unit 232 in the image display device 20 of the second embodiment. This intermediate excitation unit 332 has a gripping unit that grips a gripped portion 323 that is a part of the intermediate portion of the optical fiber 12, a motor that rotates the optical fiber 12 around an axis that is the direction in which the optical fiber 12 extends in the gripping unit, and a control unit that controls the rotation of the motor. The motor and control unit are operated by power supplied from a rechargeable battery 233. The control unit controls the motor so that the rotation direction is reversed every time the motor rotates by a predetermined angle.

[0041] In the image display device 30 of this modification, the power generated by the power generating unit 231 due to the vibration of the side wall 92 is charged in the rechargeable battery 233, and the motor of the intermediate vibration unit 332 operates in such a way that the rotation direction is reversed every time it rotates by a predetermined angle according to the control of the control unit by the power supplied from the rechargeable battery 233. As a result, the optical fiber 12 rotates about the axis of the direction in which the optical fiber 12 extends in the gripping unit, relative to the first end 121 fixed to the housing 111 and the second end 122 fixed to the helmet. This rotation causes a twist in the optical fiber 12, and the rotation direction is further reversed every time it rotates by a predetermined angle, causing a torsional vibration in the optical fiber 12. This torsional vibration causes the shape (curvature) of the optical fiber 12 to fluctuate, and the weighting of each propagation mode of the laser light propagating through the optical fiber 12 to change. This also causes a fluctuation in the speckle, and the image display device 30The user will not be able to see the speckles.

[0042] According to the image display device 30 of this modification, as with the image display device 20 of the second embodiment, no power is required to vibrate the optical fiber 12, and it is possible to suppress the influence of laser light interference on image degradation while keeping running costs low. Furthermore, the occurrence of torsional vibration in the optical fiber 12 causes a greater change in the shape of the optical fiber 12 than the occurrence of reciprocating vibration, so that it is possible to more reliably prevent the user from perceiving the interference pattern of the laser light.

[0043] In the image display device 30 of this modified example, a torsional vibration other than the reciprocating vibration of the moving body occurs in the middle part of the optical fiber 12. do.

[0044] (4) Third embodiment (4-1) Configuration of the image display device according to the third embodiment 5 shows a schematic configuration of an image display device 40 of the third embodiment. This image display device 40 has a laser light source 11, an optical fiber 12, a vibration damping material 43, an image display element 14, and a half mirror 15. The configurations of the laser light source 11, the optical fiber 12, the image display element 14, and the half mirror 15 are similar to those in the image display device 10 of the first embodiment, and therefore detailed description thereof will be omitted.

[0045] The vibration-damping material 43 is made of a spring, one end of which is fixed to the floor 91 of the moving body, and the other end of which is fixed to a fixed point 423 located in the middle of the optical fiber 12. Note that the vibration-damping material 43 is not limited to a spring, and may be an elastic body such as rubber or urethane foam.

[0046] (4-2) Operation of the image display device according to the third embodiment The operation of the image display device 40 of the third embodiment will be described. The image display device 40 is used when a moving object is moving. As with the image display device 10 of the first embodiment, an image is displayed on the transmissive liquid crystal panel of the image display element 14, and laser light is emitted from the laser light source 11, so that the image displayed on the transmissive liquid crystal panel is reflected by the half mirror 15. This allows the image displayed on the image display element 14 to be visually recognized as a virtual image by the user.

[0047] Vibrations occurring on the floor 91 when the moving object moves are transmitted to the first end 121 of the optical fiber 12 via the housing 111. Meanwhile, since the fixed point 423 in the middle part of the optical fiber 12 is connected to the floor 91 by the vibration-damping material 43, the fixed point 423 of the optical fiber 12 and its surroundings are a free vibration part that can vibrate separately from the floor 91. As a result, the first end 121 and the free vibration part vibrate differently, so that the shape (curvature) of the optical fiber 12 fluctuates, and the weighting of each propagation mode of the laser light propagating through the optical fiber 12 changes. As a result, the speckles also fluctuate, and the user of the image display device 40 cannot see the speckles.

[0048] According to the image display device 40 of the third embodiment, since no power is required for applying vibration, it is possible to reduce running costs and to suppress the influence of laser light interference on image degradation.

[0049] (5) Other modifications The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the present invention.

[0050] For example, in the image display device 10 of the first embodiment, the fixed portion 123 of the middle portion of the optical fiber 12 is fixed to the side wall 92 of the moving body, but instead, it may be fixed to the ceiling of the moving body or to a position on the floor 91 away from the housing 111. Similarly, the image display device of the second embodiment and its modified example 20 , 30 In this case, the power generation unit 231 may be fixed to the ceiling of the moving body or to a position on the floor 91 away from the housing 111.

[0051] In the image display device 40 of the third embodiment, one end of the spring, which is the vibration-damping material 43, is fixed to the floor 91 of the moving body, but it may be fixed to a part of the moving body other than the floor 91, such as a side wall or a ceiling. Alternatively, instead of the vibration-damping material 43, a string may be tied to the middle part of the optical fiber 12, and the end of the string may be fixed to the ceiling of the moving body.

[0052] As a modification of the third embodiment, a combination of a pendulum that undergoes a pendulum motion at a predetermined natural frequency in response to the vibration of a moving body and a mechanism that transmits the pendulum motion of the pendulum to the optical fiber as a torsional vibration can be used instead of the vibration-damping material 43. With this configuration, as with the image display device 30 of the modification of the second embodiment, no power is required to vibrate the optical fiber 12, and the influence of the interference of the laser light on image degradation can be suppressed while keeping running costs low. In addition, the torsional vibration of the optical fiber 12 causes a larger change in the shape of the optical fiber 12 than the case where a reciprocating vibration occurs, so that it is possible to more reliably prevent the user from seeing the interference pattern of the laser light.

[0053] In each of the above embodiments, an HMD in which a visor attached to a helmet worn by a user serves as a half mirror has been described as an example, but something other than a visor, such as goggles, may be used as the half mirror, and the present invention may be applied to a HUD that uses a half mirror installed inside a moving body.

[0054] [Aspects] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0055] (Section 1) One embodiment of the mobile body mounted The image display device for A laser light source installed in a first portion of the moving object; an optical fiber having one end disposed at a position where the laser light emitted from the laser light source is incident; an image display element disposed between the other end of the optical fiber and a display surface; A second portion of the movable body, which is different from the first portion, is fixed to an intermediate portion of the optical fiber. Fixed part and Equipped with.

[0056] The mobile object according to claim 1 mounted In the image display device for mobile phones, the optical fiber vibrates in the same way as a first part of the moving object at the end on the light source side, and in the middle part, vibrates in the same way as a second part different from the first part. Therefore, the end and middle parts vibrate differently, and the shape (curvature) of the optical fiber fluctuates, and the weighting of each propagation mode of the laser light propagating through the optical fiber changes. This causes fluctuations in the speckles, and the movement of the moving object. mounted Therefore, the user of the image display device will be unable to perceive the speckles.

[0057] The mobile object according to claim 1 mounted According to the image display device for use, since no power is required for applying vibration to the intermediate portion, it is possible to reduce running costs and to suppress the influence of laser light interference on image degradation.

[0058] (Section 2) Another aspect of the mobile body mounted The image display device for A laser light source installed at a first position of the moving object; an optical fiber having one end disposed at a position where the laser light emitted from the laser light source is incident; an image display element disposed between the other end of the optical fiber and a display surface; A power generation unit that converts the vibration of the moving body into electric power; an intermediate vibration unit that vibrates an intermediate portion of the optical fiber by electric power from the power generation unit; Equipped with.

[0059] 2. The mobile body according to claim 2 mounted In the image display device for use, the moving object described in the first aspect is mountedFor the same reason as in the image display device for mobile phones, the optical fiber vibrates differently at the end and middle parts, causing the shape (curvature) to fluctuate, and the weighting of each propagation mode of the laser light propagating through the optical fiber changes. This causes fluctuations in the speckle, which can affect the movement of the moving object. mounted Therefore, the user of the image display device will be unable to perceive the speckles.

[0060] 2. The mobile body according to claim 2 mounted According to the image display device for use, since no power is required for applying vibration to the intermediate portion, it is possible to reduce running costs and to suppress the influence of laser light interference on image degradation.

[0061] (Section 3) 2. The mobile body according to claim 2 mounted The image display device further includes a rechargeable battery that is charged with the power converted by the power generating unit and supplies the charged power to the intermediate vibration unit.

[0062] 3. The mobile body according to claim 3 mounted According to the image display device for use, the power converted by the power generating unit is temporarily charged in a rechargeable battery and then supplied to the intermediate excitation unit, so that stable power can be supplied to the intermediate excitation unit and the intermediate portion of the optical fiber can be excited with stable amplitude and frequency. This makes it possible to more reliably suppress the effect of laser light interference on image degradation.

[0063] (Section 4) A mobile object according to claim 2 or 3. mounted In the image display device for use, the intermediate vibration exciting unit is a torsional vibration exciting unit that applies torsional vibration to an intermediate portion of the optical fiber.

[0064] The mobile body according to claim 4 mounted According to the image display device, the torsional vibration generated in the optical fiber causes a greater change in the shape of the optical fiber than when reciprocating vibration is generated, thereby making it possible to more reliably prevent the user from seeing the interference pattern of the laser light.

[0065] (Section 5) Another aspect of the moving body mounted The image display device for A laser light source installed at a first position of the moving object; an optical fiber having one end disposed at a position where the laser light emitted from the laser light source is incident; an image display element disposed between the other end of the optical fiber and a display surface; A moving body comprising: mounted In the image display device for A free vibration portion is provided in the middle portion of the optical fiber.

[0066] The mobile body according to claim 5 mounted In an image display device for mobile phones, the optical fiber vibrates differently at the end on the laser light source side and the free vibration part, so the shape (curvature) of the optical fiber fluctuates, and the weighting of each propagation mode of the laser light propagating through the optical fiber changes. This causes fluctuations in the speckle, which can cause the moving object to move. mounted Therefore, the user of the image display device will be unable to perceive the speckles.

[0067] The mobile body according to claim 5 mounted According to the image display device for use, since no power is required to impart vibration to the free vibration part, it is possible to reduce the running costs and to suppress the influence of laser light interference on image degradation.

[0068] (Section 6) The mobile body according to claim 5 mounted The image display device further includes a torsional vibration excitation section that converts vibration of the moving body into torsional vibration and applies the torsional vibration to the free vibration portion.

[0069] 6. The mobile body according to claim 6 mounted According to the image display device, the torsional vibration generated in the optical fiber causes a greater change in the shape of the optical fiber than when reciprocating vibration is generated, thereby making it possible to more reliably prevent the user from seeing the interference pattern of the laser light. [Explanation of symbols]

[0070] 10, 20, 30, 40...Image display device 11...Laser light source 111…Housing 112, 113, 141…Lens 12...Optical fiber 121...First end 122…Second end 123, 223...Fixed part 13, 232, 332...Intermediate vibration section 14...Image display element 142...Diffusion plate 143…Signal line 15...Half mirror 151...Display optical system 231…Power Generation Division 233…Rechargeable battery 323...Gripped part 423…Fixed point 43...Vibration damping material 91…Floor 92...Side wall

Claims

1. A laser light source installed at a first portion of the moving object; an optical fiber, one end of which is disposed at a position where the laser light emitted from the laser light source is incident; and, an image display element disposed between the other end of the optical fiber and a display surface; The first portion of the moving body is made of a material or has a thickness different from that of the first portion of the moving body, and when the moving body moves, A second portion that vibrates differently from the first portion is arranged so that the vibration of the second portion is transmitted to the intermediate portion of the optical fiber. a fixing portion for fixing the intermediate portion so that a user cannot see speckles in an image as a result of the speckles being transmitted to the intermediate portion; The image display element is a transmissive liquid crystal panel, and the light propagates through the optical fiber and The laser light emitted from the fiber passes through the image display element to generate a virtual image.

4. A mobile-mounted image display device, comprising: a display unit for displaying an image on said display surface;

Images