JP2018165751A - Image display device and head-mounted display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image display device and a head-mounted display that can be reduced in size.SOLUTION: An image display device comprises: a scanning part that scans light emitted from a light source; and a light dimming part that forms at least part of a storage part storing the scanning part, and dims the light emitted from the light source and light scanned by the scanning part. The light dimming part includes a light guide part that guides the light emitted from the light source and transmits the light scanned by the scanning part, and a diffraction element that separates the light emitted from the light source into regular reflection light and diffraction light. One light of the regular reflection light and the diffraction light is guided in the light guide part, and the other light is transmitted through the light guide part and guided to the scanning part; the other light scanned by the scanning part is transmitted through the light guide part.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an image display device and a head mounted display.

  As one of the image display technologies of an image display device, a technology for irradiating a laser directly on the retina of an eye and allowing a user to visually recognize an image has recently attracted attention. For example, Patent Document 1 describes an image display device that includes a laser light source and a scanning unit that scans laser light onto the imaging surface of the retina of the eye. In addition, the image display device of Patent Document 1 is designed to protect the retina from laser light by disposing the ND filter between the laser light source and the scanning unit and dimming the laser light.

JP 2005-55780 A

  However, with such a configuration, an ND filter must be added to reduce the laser light, and it is difficult to reduce the size of the image display device.

  An object of the present invention is to provide an image display device and a head mounted display that can be miniaturized.

  Such an object is achieved by the present invention described below.

An image display device of the present invention includes a scanning unit that scans light emitted from a light source,
A light-attenuating part that constitutes at least a part of the accommodating part that accommodates the scanning part, and that attenuates each of the light emitted from the light source and the light scanned by the scanning part;
The dimming unit guides light emitted from the light source, and transmits light scanned by the scanning unit; and
A diffraction element that separates light emitted from the light source into specularly reflected light and diffracted light,
One of the regular reflection light and the diffracted light is guided in the light guide unit, and the other light is transmitted through the light guide unit and guided to the scanning unit,
The other light scanned by the scanning unit is transmitted through the light guide unit.
According to such a configuration, since a part of the storage part is a dimming part, the number of parts of the image display device is reduced and the size is reduced as compared with the case where the dimming part is arranged separately from the storing part. Can be achieved.

In the image display device of the present invention, the light guide unit includes a first surface located outside the storage unit, and a second surface positioned inside the storage unit,
The diffraction element is disposed on the first surface side,
It is preferable that light emitted from the light source is incident from the second surface side of the light guide unit.
Thereby, it becomes easy to arrange | position a light source in a storage part, and size reduction of an image display apparatus can be achieved.

In the image display device of the present invention, the one light has an incident angle with respect to each of the first surface and the two surfaces larger than a critical angle,
The other light preferably has an incident angle with respect to the second surface smaller than a critical angle.
Thereby, one light is more reliably guided in the light guide unit, and the other light is transmitted through the light guide unit and guided to the scanning unit.

In the image display device of the present invention, the second surface has a first incident region where light emitted from the light source is incident and a second incident region where light scanned by the scanning unit is incident. ,
It is preferable that the first incident region and the second incident region face different directions.
Thereby, the light reflected by the first incident region is less likely to be directed to the scanning unit, and the generation of stray light can be effectively suppressed.

In the image display device according to the aspect of the invention, it is preferable that the dimming unit includes a light absorption unit that is disposed in the light guide unit and absorbs the one light.
Thereby, it can suppress that one light permeate | transmits out of a light guide part. Therefore, generation of stray light can be effectively suppressed.

In the image display device of the present invention, it is preferable that the light guide unit is an ND filter.
Thereby, the structure of a light guide part becomes simple. Further, the light can be effectively reduced by the light guide portion.

The head-mounted display of the present invention includes a scanning unit that scans light emitted from a light source,
A light-attenuating part that constitutes at least a part of the accommodating part that accommodates the scanning part, and that attenuates each of the light emitted from the light source and the light scanned by the scanning part;
The dimming unit guides the light emitted from the light source, and transmits the light scanned by the scanning unit; and
A diffractive element that separates light emitted from the light source and incident on the light guide unit into specularly reflected light and diffracted light, and
One of the regular reflection light and the diffracted light is guided in the light guide unit, and the other light is transmitted through the light guide unit and guided to the scanning unit,
The other light scanned by the scanning unit is transmitted through the light guide unit.
According to such a configuration, since a part of the storage part is a light guide part, the number of parts of the head mounted display is reduced and the size is reduced as compared with the case where the light guide part is arranged separately from the storage part. Can be achieved.

1 is a top view showing an image display device according to a first embodiment of the present invention. It is a perspective view of the image display apparatus shown in FIG. It is sectional drawing which shows the display unit which the image display apparatus shown in FIG. 1 has. It is a figure which shows the structure of the modulated light production | generation part which the display unit shown in FIG. 3 has. It is a top view which shows the scanning part with which the display unit shown in FIG. 3 is provided. It is a top view which shows a deflection | deviation part. It is sectional drawing which shows the display unit which the image display apparatus concerning 2nd Embodiment of this invention has. It is sectional drawing which shows the display unit which the image display apparatus concerning 3rd Embodiment of this invention has.

  Hereinafter, preferred embodiments of an image display device and a head mounted display of the present invention will be described with reference to the accompanying drawings.

<First Embodiment>
FIG. 1 is a top view showing an image display apparatus according to the first embodiment of the present invention. FIG. 2 is a perspective view of the image display apparatus shown in FIG. FIG. 3 is a cross-sectional view showing a display unit included in the image display apparatus shown in FIG. FIG. 4 is a diagram illustrating a configuration of a modulated light generation unit included in the display unit illustrated in FIG. FIG. 5 is a plan view showing a scanning unit included in the display unit shown in FIG. FIG. 6 is a top view showing the deflection unit. In the following, for convenience of explanation, the right side for the observer is also referred to as “right” and the left side is also referred to as “left”.

  An image display device 100 shown in FIG. 1 is a head-mounted display (head-mounted image display device). Such an image display device 100 has an appearance like glasses, is used by being worn on the observer's head H, and allows the observer to visually recognize a virtual image superimposed on an external image.

  As shown in FIG. 1, the image display device 100 includes a frame 200, a display unit 300 supported by the frame 200, and a deflection unit 600. In addition, although the display unit 300 of this embodiment is provided for an observer's right eye, it is not limited to this and may be provided for the left eye. Moreover, you may have the display unit 300 provided for observer's right eyes, and the display unit 300 provided for observer's left eyes. That is, it may be a monocular head mounted display or a binocular head mounted display.

  As shown in FIG. 2, the frame 200 has a shape like a spectacle frame and supports the display unit 300. The frame 200 includes a front part 210 positioned in front of the observer's eye EY, and a pair of temple parts 220 and 230 extending from both left and right ends of the front part 210.

  The front part 210 has a rim part 211, a shade part 212 and a nose pad 213 supported by the rim part 211. Moreover, the shade part 212 has a function of suppressing transmission of external light. The shade unit 212 supports the deflection unit 600. A nose pad 213 is provided at the center of the shade portion 212. When the observer wears the image display device 100 on the head H, the nose pad 213 abuts on the nose NS of the observer and supports the image display device 100 with respect to the head H of the observer.

  The temple parts 220 and 230 are connected to the front part 210. Such temple portions 220 and 230 are configured to come into contact with the ear EA of the viewer when the viewer wears the image display device 100 on the head H. The temple portions 220 and 230 may be foldable with respect to the front portion 210 or may not be foldable.

  Although the frame 200 has been described above, the shape of the frame 200 is not illustrated as long as it can be mounted on the head H of the observer and can support the display unit 300 and the deflection unit 600. It is not limited.

  As illustrated in FIG. 3, the display unit 300 includes a modulated light generation unit 400, a scanning unit 500, a dimming unit 700, and a control unit 800. In such a display unit 300, the modulated light generation unit 400 generates the modulated light L based on the video signal from the control unit 800, the scanning unit 500 scans the modulated light L two-dimensionally, and the deflection unit 600 The modulated light L scanned by the scanning unit 500 is configured to be deflected toward the observer's eye EY. Further, the modulated light L before and after the dimming unit 700 is scanned by the scanning unit 500 is scanned. The light intensity is attenuated (attenuated). By having such a display unit 300, an observer can visually recognize an image (virtual image) corresponding to the video signal. Further, since the modulated light L is attenuated by the dimming unit 700, an image can be displayed with an appropriate brightness.

  The modulated light generation unit 400 is disposed in the temple unit 220. As shown in FIG. 4, the modulated light generation unit 400 includes a light source unit 410 having a plurality of light sources 410R, 410G, and 410B having different wavelengths, and drive circuits 420R, 420G that drive the light sources 410R, 410G, and 410B. 420B, collimator lenses 440R, 440G, and 440B that collimate the light emitted from the light sources 410R, 410G, and 410B, and the light combining unit 430.

  The light source 410R is a laser light source that emits red laser light. The light source 410G is a laser light source that emits green laser light. The light source 410B is a laser light source that emits blue laser light. By using such three colors of light, a full color image can be displayed. Thus, a clear image can be displayed by using a laser light source as the light sources 410R, 410G, and 410B. Although it does not specifically limit as light source 410R, 410G, 410B, For example, a laser diode can be used. However, the light sources 410R, 410G, and 410B are not limited to laser light sources.

  The drive circuit 420R has a function of driving the light source 410R. The drive circuit 420G has a function of driving the light source 410G. In addition, the drive circuit 420B has a function of driving the light source 410B. Further, the drive of these drive circuits 420R, 420G, and 420B is independently controlled by the control unit 800. The three laser beams emitted from the light sources 410R, 410G, and 410B driven by the driving circuits 420R, 420G, and 420B are collimated by the collimator lenses 440R, 440G, and 440B and enter the light combining unit 430, respectively. To do.

  The light combining unit 430 combines the laser beams from the light sources 410R, 410G, and 410B. In the present embodiment, the light combining unit 430 includes two dichroic mirrors 431 and 432. The dichroic mirror 431 has a function of transmitting red light and reflecting green light. The dichroic mirror 432 has a function of transmitting red light and green light and reflecting blue light. By using such dichroic mirrors 431 and 432, the light of three colors of red light, green light and blue light from the light sources 410R, 410G and 410B is synthesized. At this time, the control unit 800 independently modulates the intensity of the laser light from the light sources 410R, 410G, and 410B to obtain the modulated light L of a predetermined color. The configuration of the light combining unit 430 is not particularly limited as long as the laser light from the light sources 410R, 410G, and 410B can be combined.

  The configuration of the modulated light generation unit 400 has been described above, but the configuration of the modulated light generation unit 400 is not particularly limited as long as the modulated light L can be generated. For example, the modulated light generation unit 400 may be disposed in a portion other than the frame 200 as long as it can generate the modulated light L, and guide the modulated light L to the exit position of the temple unit 220 using an optical fiber or the like. For example, the modulated light generation unit 400 may be stored in a housing different from the image display device 100, and the modulated light L may be guided from the housing to the image display device 100 through an optical fiber. Moreover, the modulated light generation part 400 should just have at least 1 light source, and it does not specifically limit about the color of the light radiate | emitted from the light source.

  The scanning unit 500 is disposed in the temple unit 220. The scanning unit 500 is an optical scanner that two-dimensionally scans the modulated light L emitted from the modulated light generation unit 400 toward the deflecting unit 600.

  The scanning unit 500 is an optical scanner that can swing around two axes. As shown in FIG. 5, the scanning unit 500 includes a movable unit 510 having a mirror 511, shaft units 521 and 522 that support the movable unit 510 so that the movable unit 510 can swing (rotate) about the axis J <b> 1, a shaft unit 521, A drive frame portion 530 that supports 522, shaft portions 541 and 542 that support the drive frame portion 530 so as to be swingable (turnable) about an axis J2 orthogonal to the axis J1, and a frame that supports the shaft portions 541 and 542. And a support portion 550 having a shape. Such a scanning unit 500 can be moved by swinging the movable unit 510 about the axis J1 relative to the drive frame unit 530 while swinging the drive frame unit 530 relative to the support unit 550 about the axis J2. Since the portion 510 swings around both the axes J1 and J2, the modulated light L reflected by the mirror 511 can be scanned two-dimensionally. The scanning unit 500 scans the modulated light L in the left-right direction (horizontal direction) of the frame 200 by swinging the movable unit 510 around the axis J1, and the vertical direction of the frame 200 (by swinging around the axis J2). The modulated light L is scanned in the vertical direction).

  In addition, the scanning unit 500 includes a detection unit 560 that detects the orientation of the movable unit 510. The detection unit 560 includes two piezoelectric bodies 561 and 562 provided at the bases of the shaft portions 521 and 541. The detection unit 560 detects the direction of the movable unit 510 by obtaining the tilt angle around the axis J1 and the tilt angle around the axis J2 of the movable unit 510 from the resistance value changes of the piezoelectric bodies 561 and 562. ing. The direction of the movable unit 510 detected by the detection unit 560 is transmitted to the control unit 800, and the control unit 800 emits the modulated light L from the modulated light generation unit 400 in accordance with the direction and timing of the movable unit 510. Thus, the drive of the modulated light generation unit 400 is controlled.

  Thus, by using an optical scanner that can swing around two axes as the scanning unit 500, the configuration and arrangement (particularly alignment) of the scanning unit 500 can be simplified, and the scanning unit 500 can be downsized. Can be achieved.

  The configuration of the scanning unit 500 is not particularly limited as long as the modulated light L can be scanned two-dimensionally. For example, the scanning unit 500 may be configured to include two optical scanners that scan the modulated light L one-dimensionally, or may be configured to use a polygon mirror or a galvanometer mirror instead of the optical scanner. Good.

  The deflecting unit 600 is provided on the front unit 210 and is disposed so as to be positioned in front of the right eye of the observer when in use. As shown in FIG. 6, the deflecting unit 600 is large enough to cover the right eye of the observer, and enters the observer's eye EY as image light with the modulated light L scanned by the scanning unit 500. Has the function of Such a deflection | deviation part 600 is comprised by the hologram element (hologram mirror) which is one of the diffraction gratings, for example. This hologram element is a semi-transmissive film having a property of diffracting light in a specific wavelength band and transmitting light in other wavelength bands. Thereby, the observer can visually recognize the image (virtual image) formed by the image light while visually recognizing the external image. That is, a see-through type head mounted display can be realized. The configuration of the deflection unit 600 is not particularly limited, and for example, a half mirror can be used.

  As shown in FIG. 3, the dimming unit 700 is disposed in the temple unit 220, and is positioned between the scanning unit 500 and the deflecting unit 600 (see FIG. 1) on the optical path. The dimming unit 700 has a function of dimming the modulated light L emitted from the modulated light generation unit 400. Here, since the light sources 410R, 410G, and 410B described above are laser light sources, it is difficult to reduce the intensity (output) of the laser light. Further, when the intensity of the laser beam is weakened, it becomes difficult to generate the modulated light L of a predetermined color. For this reason, if an image formed with the modulated light L having the intensity emitted from the modulated light generation unit 400 is guided to the observer's eye EY, the image becomes too bright and difficult to view. Therefore, in the present embodiment, the intensity of the modulated light L is weakened using the dimming unit 700. Thereby, it becomes an image which is easy to visually recognize with moderate brightness. Further, by reducing the intensity of the modulated light L, the retina can be protected from the modulated light L.

  The modulated light L is preferably attenuated to an intensity of 1 μW or less before entering the eye EY. The modulated light L emitted from the modulated light generation unit 400 may have an intensity of about 100 mW. In this case, the modulated light L needs to be reduced to about 1/100000.

  The light reduction unit 700 attenuates the modulated light L emitted from the modulated light generation unit 400 before (upstream side) and after (downstream side) scanning with the scanning unit 500. In this way, the modulated light L can be reduced more effectively by dimming the modulated light L in a plurality of times. As shown in FIG. 3, such a light reduction unit 700 includes a light guide unit 710, a diffraction element 720 provided in the light guide unit 710, a light absorption unit 730, and an antireflection film 740.

  The light guide unit 710 has a plate shape having an outer surface 711 (first surface) and an inner surface 712 (second surface). Note that the outer surface 711 and the inner surface 712 are substantially parallel. However, the shape of the light guide unit 710 is not particularly limited.

  In addition, the light guide unit 710 has a function of uniformly diminishing the light traveling in the thickness direction (without having wavelength dependency). As such a light guide unit 710, for example, an ND filter including a glass substrate in which a light absorbing material is dispersed can be used. Thereby, the structure of the light guide part 710 becomes simple. However, the configuration of the light guide unit 710 is not particularly limited.

  In addition, the thickness Z of the light guide unit 710 is not particularly limited, but may be, for example, 0.5 mm or more and 5 mm or less. In addition, the length Y of the light guide unit 710 is not particularly limited, but may be, for example, 5 mm or more and 10 mm or less. Thereby, the light guide part 710 can be made sufficiently small while exhibiting the function as the light guide part 710.

  Further, the light transmittance in the thickness direction of the light guide unit 710 varies depending on the intensity of the modulated light L generated by the modulated light generation unit 400, but is preferably 1% or more and 50% or less, for example. % To 20% is more preferable. Thereby, the modulated light L can be effectively reduced by the light guide unit 710.

  In addition, the inner surface 712 of the light guide unit 710 is provided with a first incident region 712a on which the modulated light L generated by the modulated light generation unit 400 is incident, and the light guide unit 710 is modulated from the first incident region 712a. Light L enters. Here, the incident angle of the modulated light L with respect to the first incident region 712a is slightly shifted from 0 ° (for example, about 5 ° to 20 °). Thereby, it is possible to suppress the modulated light L reflected by the first incident region 712a from returning to the light sources 410R, 410G, and 410B. Therefore, the driving of the light sources 410R, 410G, 410B is more stable. However, the incident angle of the modulated light L with respect to the first incident region 712a is not particularly limited, and may be 0 °.

  Further, a light shielding unit 790 is provided between the modulated light generation unit 400 and the scanning unit 500. Accordingly, since the modulated light L reflected by the first incident region 712a is shielded by the light shielding unit 790, it is possible to prevent the modulated light L from being scanned by the scanning unit 500 and becoming stray light. The light-shielding part 790 is not particularly limited, but for example, it is preferable to use a light-absorbing member having a light absorption property such as a light-absorbing part 730 described later. However, the configuration of the light shielding unit 790 is not particularly limited. Further, the light shielding portion 790 may be omitted.

  On the other hand, a reflective diffractive element 720 is provided on the outer surface 711 of the light guide unit 710, and the modulated light L incident on the light guide unit 710 from the first incident region 712a is specularly reflected by the diffractive element 720. The diffraction element 720 is not particularly limited, and a hologram element (hologram mirror) that is one of diffraction gratings can be used.

  Further, the regular reflection light L ′ has an incident angle with respect to the inner surface 712 smaller than the critical angle, and is refracted and transmitted to the outside of the light guide unit 710 through the inner surface 712. The transmitted regular reflection light L ′ is guided to the scanning unit 500 and scanned by the scanning unit 500. On the other hand, the incident angle with respect to the inner surface 712 and the outer surface 711 is larger than the critical angle, and the diffracted light L ″ propagates in the light guide unit 710 while repeating total reflection. Therefore, the diffracted light L ″ is scanned by the scanning unit 500. It will not be done. Thus, by scanning only the regular reflection light L ′ with the scanning unit 500, the modulated light L can be effectively reduced. Further, by decreasing the modulated light L before scanning by the scanning unit 500, the temperature rise of the scanning unit 500 (particularly the mirror 511) can be suppressed, and the scanning unit 500 is driven by the temperature rise. Changes in characteristics can be reduced.

  Here, a light-absorbing unit 730 is provided on the side surface of the light guide unit 710, specifically on the side surface located downstream in the propagation direction of the modulated light L. The light absorption unit 730 absorbs the diffracted light L ″ propagating through the light guide unit 710 to form the end of the diffracted light L ″. Therefore, it is possible to suppress the diffracted light L ″ from passing through the light guide 710 and becoming stray light.

  Since the diffracted light L ″ is also attenuated by propagating through the light guide 710, it is sufficiently attenuated until it reaches the light absorber 730. Therefore, the light diffracted light L ″ is absorbed by the light absorber 730. While absorbing more reliably, the heat_generation | fever of the light absorption part 730 by absorption of light can be reduced effectively. The light absorption unit 730 is not particularly limited as long as it can absorb the diffracted light L ″. For example, the light absorption unit 730 can be composed of a black light-absorbing paint applied to the side surface of the light guide unit 710. The light absorption unit 730 may be omitted.

  In addition, the inner surface 712 of the light guide unit 710 is provided with a second incident region 712b on which the specularly reflected light L ′ (modulated light L) scanned by the scanning unit 500 is incident, and is guided from the second incident region 712b. The specularly reflected light L ′ (modulated light L) enters the light unit 710. Further, the specularly reflected light L ′ incident on the light guide 710 from the second incident region 712 b has a smaller incident angle with respect to the outer surface 711 than the critical angle, and is refracted and transmitted to the outside of the light guide 710 via the outer surface 711. The specularly reflected light L ′ (modulated light L) transmitted through the light guide unit 710 in this way is guided to the deflecting unit 600. In this way, the specularly reflected light L ′ (modulated light L) scanned by the scanning unit 500 is configured to transmit the light guide unit 710, thereby further reducing the specularly reflected light L ′ (modulated light L). be able to.

  Here, an antireflection film 740 is disposed on the inner surface 712 of the light guide 710. This effectively reflects the reflected modulated light L incident on the light guide 710 from the first incident region 712a and reflects the modulated light L (regularly reflected light L ′) incident on the light guide 710 from the second incident region 712b. Can be suppressed. Note that the antireflection film 740 can be formed of, for example, a dielectric multilayer film in which a plurality of high refractive index layers and low refractive index layers are alternately stacked. However, the configuration of the antireflection film 740 is not particularly limited and may be omitted.

  The display unit 300 has been described above. For example, the light transmittance in the thickness direction of the light guide 710 is 5%, and the incident angle of the modulated light L incident on the diffraction element 720 is 30 ° (the optical path length is 1.15 of the thickness of the light guide 710). In the case where 20% of the modulated light L incident on the diffractive element 720 is specularly reflected light L ′ and 80% is diffracted light L ″, the modulated light L is incident from the first incident region 712a. Until it reaches the diffractive element 720, and is dimmed to 3.15%. By being separated into specularly reflected light L ′ by the diffractive element 720, the light is further reduced to 20% and is refracted and transmitted through the inner surface 712. Then, the light is further reduced to 3.15% and further reduced to 5% by being transmitted by the light guide unit 710 after being scanned by the scanning unit 500. That is, the modulated light L before being incident on the eye EY. Can be reduced to about 1 / 100,000. By dimming the modulated light L in a plurality of times, the modulated light L can be sufficiently dimmed in the remaining portion even if the dimming function cannot be exhibited in part due to damage. In addition, since the region where the modulated light L is attenuated is different at each stage, local heat generation of the light guide unit 710 can be suppressed, so that damage to the light guide unit 710 can be suppressed. Thus, the reliability of the image display apparatus 100 is improved, and the modulated light L is reflected by the light guide unit 710 a plurality of times and is attenuated, so that the dimming unit 700 is obtained in order to obtain a desired dimming rate. Therefore, the ND filter can be easily designed.

  In addition, the image display apparatus 100 includes a storage unit 110 that stores the modulated light generation unit 400, the scanning unit 500, the dimming unit 700, and the control unit 800. Accordingly, these parts can be protected from moisture, impact, dust, and the like, and the reliability of the image display apparatus 100 is improved. In addition, although it does not specifically limit, it is preferable that the accommodating part 110 has a dust-proof structure or a drip-proof structure. Thereby, said effect becomes more remarkable.

  Further, the storage unit 110 is fixed to the frame 200. The storage unit 110 includes a base 111 having an opening and a cover 112 arranged so as to close the opening. Further, the cover part 112 is configured by a light guide part 710. As described above, by using the light guide unit 710 as the cover unit 112, the number of components and the size of the image display device 100 can be reduced and downsized as compared with the case where the cover unit 112 and the light guide unit 710 are separately provided. be able to. In the present embodiment, the base 111 is separated from the frame 200 (the temple portion 220), but the base 111 may be integrated with the frame 200. That is, the temple part 220 may also serve as the base part 111. Further, the dimming unit 700 may constitute the entire storage unit 110.

  The image display device 100 (head mounted display) has been described above. As described above, such an image display device 100 (head mounted display) houses the scanning unit 500 that scans the modulated light L (light) emitted from the modulated light generation unit 400 (light source), and the scanning unit 500. Constituting at least a part of the storage unit 110 (the cover unit 112) to reduce the modulated light L (light) emitted from the modulated light generation unit 400 and the modulated light L (light) scanned by the scanning unit 500, respectively. A dimming portion 700 that emits light. The dimming unit 700 guides the modulated light L (light) emitted from the modulated light generation unit 400 (light source) and transmits the modulated light L (light) scanned by the scanning unit 500. 710 and a diffractive element 720 that separates the modulated light L (light) emitted from the modulated light generator 400 (light source) and incident on the light guide 710 into specularly reflected light L ′ and diffracted light L ″. Then, one of the regularly reflected light L ′ and the diffracted light L ″ (diffracted light L ″ in this embodiment) is guided in the light guide 710 and the other light (this embodiment). In the embodiment, the regular reflection light L ′) is transmitted through the light guide unit 710 and guided to the scanning unit 500, and the regular reflection light L ′ (the other light) scanned by the scanning unit 500 is transmitted through the light guide unit 710. .

  According to such a configuration, since part of the storage unit 110 is the dimming unit 700, the number of parts of the image display device 100 is larger than when the dimming unit 700 is arranged separately from the storage unit 110. Reduction and downsizing can be achieved. The dimming unit 700 dims the modulated light L emitted from the modulated light generation unit 400 before (upstream) and after (downstream) the scanning unit 500 scans. In this way, the modulated light L can be reduced more effectively by dimming the modulated light L in a plurality of times.

  In addition, as described above, the light guide unit 710 includes the outer surface 711 (first surface) positioned outside the storage unit 110 and the inner surface 712 (second surface) positioned inside the storage unit 110. ing. The diffractive element 720 is disposed on the outer surface 711 side, and the modulated light L (light) emitted from the modulated light generation unit 400 (light source) enters from the inner surface 712 side of the light guide unit 710. Thereby, it becomes easy to arrange the modulated light generation unit 400 in the storage unit 110, and the image display device 100 can be downsized.

  Further, as described above, the diffracted light L ″ (one light) has an incident angle with respect to each of the outer surface 711 (first surface) and the inner surface 712 (second surface) larger than the critical angle, and the regular reflected light L ′. (Another light) has an incident angle with respect to the inner surface 712 (second surface) smaller than the critical angle. Thereby, the diffracted light L ″ is more reliably guided in the light guide unit 710, and the regular reflection light L 'Is transmitted through the light guide 710 and guided to the scanning unit 500.

  Further, as described above, the dimming unit 700 includes the light absorption unit 730 that is disposed in the light guide unit 710 and absorbs the diffracted light L ″ (one light). Transmission through the outside of the light guide unit 710 can be suppressed. Therefore, generation of stray light can be effectively suppressed.

  As described above, the light guide unit 710 is an ND filter. Thereby, the structure of the light guide part 710 becomes simple. Further, the modulated light L can be effectively reduced by the light guide unit 710.

Second Embodiment
FIG. 7 is a cross-sectional view showing a display unit included in the image display apparatus according to the second embodiment of the present invention.

  Hereinafter, the second embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

  The image display apparatus 100 according to the second embodiment is substantially the same as the first embodiment described above except that the configuration of the dimming unit 700 (particularly, the light guide unit 710) is different. In FIG. 7, the same reference numerals are given to the same components as those in the above-described embodiment.

  As shown in FIG. 7, the light guide unit 710 of the present embodiment has two surfaces 712 </ b> A and 712 </ b> B whose inner surfaces 712 have different directions. Further, the surface 712A is non-parallel to the outer surface 711, and the surface 712B is substantially parallel to the outer surface 711. The angle θ formed by the surfaces 712A and 712B is 180 ° or more and 270 ° or less. In addition, a first incident region 712a is provided on the surface 712A, and a second incident region 712b is provided on the surface 712B. That is, the inner surface 712 is incident with the first incident region 712a where the modulated light L (light) emitted from the modulated light generation unit 400 (light source) is incident and the modulated light L (light) scanned by the scanning unit 500. A second incident region 712b, and the first incident region 712a and the second incident region 712b are directed in different directions. With such a configuration, the modulated light L reflected by the first incident region 712a is less likely to be directed to the scanning unit 500, and stray light is generated without providing the light shielding unit 790 as in the first embodiment described above. Can be effectively suppressed. Therefore, the number of parts can be reduced and the size can be reduced as compared with the first embodiment described above.

  Also according to the second embodiment, the same effects as those of the first embodiment described above can be exhibited.

<Third Embodiment>
FIG. 8 is a cross-sectional view showing a display unit included in the image display apparatus according to the third embodiment of the present invention.

  Hereinafter, the third embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

  The image display apparatus 100 according to the third embodiment is substantially the same as the first embodiment described above except that the configuration of the dimming unit 700 is different. In FIG. 8, the same reference numerals are given to the same components as those in the above-described embodiment.

  As shown in FIG. 8, in the dimming unit 700 of this embodiment, the diffraction element 720 is disposed to be inclined with respect to the inner surface 712. Then, the regular reflection light L ′ separated by the diffraction element 720 guides the light guide part 710. On the other hand, the diffracted light L ″ is transmitted through the light guide 710 and guided to the scanning unit 500, and the diffracted light L ″ scanned by the scanning unit 500 is transmitted through the light guide 710 and guided to the deflecting unit 600.

  Also according to the third embodiment, the same effects as those of the first embodiment described above can be exhibited.

  While the image display device and the head mounted display of the present invention have been described based on the illustrated embodiment, the present invention is not limited to this. For example, in the image display device of the present invention, the configuration of each unit can be replaced with an arbitrary configuration having the same function, and other arbitrary configurations can be added. Moreover, you may combine each embodiment suitably.

  Further, the image display device of the present invention is not limited to being applied to a glasses-type head mounted display as long as it forms a virtual image as an image visually recognized by an observer. For example, a helmet type or a headset type The present invention can also be applied to a head-mounted display, an image display device that is supported by a body such as an observer's neck and shoulder, and the like. Further, in the above-described embodiment, the case where the entire image display apparatus is mounted on the observer's head has been described as an example. However, the image display apparatus includes a portion mounted on the observer's head and an observer's head. You may have a part with which a part other than a head is mounted | worn or carried.

  In the above-described embodiments, the configuration of the binocular transmissive head mounted display has been representatively described. For example, a non-transmissive head mount in which an outside scene is blocked when the observer wears the head mounted display is used. It may be a display configuration. Further, the image display device of the present invention may include a device for outputting sound such as a speaker or a headphone.

  DESCRIPTION OF SYMBOLS 100 ... Image display apparatus 110 ... Storage part, 111 ... Base part, 112 ... Cover part, 200 ... Frame, 210 ... Front part, 211 ... Rim part, 212 ... Shade part, 213 ... Nose pad, 220, 230 ... Temple part , 300 ... display unit, 400 ... modulated light generation unit, 410 ... light source unit, 410B, 410G, 410R ... light source, 420B ... drive circuit, 420G ... drive circuit, 420R ... drive circuit, 430 ... light synthesis unit, 431, 432 ... Dichroic mirror, 440B, 440G, 440R ... collimator lens, 500 ... scanning part, 510 ... movable part, 511 ... mirror, 521, 522 ... shaft part, 530 ... drive frame part, 541, 542 ... shaft part, 550 ... support part 560 ... detection unit, 561, 562 ... piezoelectric body, 600 ... deflection unit, 700 ... darkening unit, 710 ... light guide unit 711 ... outer surface, 712 ... inner surface, 712A, 712B ... surface, 712a ... first incident region, 712b ... second incident region, 720 ... diffractive element, 730 ... light-absorbing part, 740 ... antireflection film, 790 ... light shielding part, 800 ... control unit, EA ... ear, EY ... eye, H ... head, J1, J2 ... axis, L ... modulated light, L '... regularly reflected light, L "... diffracted light, NS ... nose

Claims (7)

A scanning unit that scans light emitted from the light source;
A light-attenuating part that constitutes at least a part of the accommodating part that accommodates the scanning part, and that attenuates each of the light emitted from the light source and the light scanned by the scanning part;
The dimming unit guides light emitted from the light source, and transmits light scanned by the scanning unit; and
A diffraction element that separates light emitted from the light source into specularly reflected light and diffracted light,
One of the regular reflection light and the diffracted light is guided in the light guide unit, and the other light is transmitted through the light guide unit and guided to the scanning unit,
The image display device characterized in that the other light scanned by the scanning section passes through the light guide section. The light guide unit has a first surface located outside the storage unit, and a second surface located inside the storage unit,
The diffraction element is disposed on the first surface side,
The image display apparatus according to claim 1, wherein light emitted from the light source enters from the second surface side of the light guide unit. The one light has an incident angle with respect to each of the first surface and the two surfaces larger than a critical angle,
The image display apparatus according to claim 2, wherein an incident angle of the other light with respect to the second surface is smaller than a critical angle. The second surface has a first incident region where light emitted from the light source is incident and a second incident region where light scanned by the scanning unit is incident,
The image display apparatus according to claim 2, wherein the first incident area and the second incident area are directed in different directions.   5. The image display device according to claim 1, wherein the light reduction unit includes a light absorption unit that is disposed in the light guide unit and absorbs the one light. 6.   The image display device according to claim 1, wherein the light guide unit is an ND filter. A scanning unit that scans light emitted from the light source;
A light-attenuating part that constitutes at least a part of the accommodating part that accommodates the scanning part, and that attenuates each of the light emitted from the light source and the light scanned by the scanning part;
The dimming unit guides the light emitted from the light source, and transmits the light scanned by the scanning unit; and
A diffractive element that separates light emitted from the light source and incident on the light guide unit into specularly reflected light and diffracted light, and
One of the regular reflection light and the diffracted light is guided in the light guide unit, and the other light is transmitted through the light guide unit and guided to the scanning unit,
The head-mounted display, wherein the other light scanned by the scanning unit is transmitted through the light guide unit.

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