WO2022181346A1 - 画像投影装置 - Google Patents
画像投影装置 Download PDFInfo
- Publication number
- WO2022181346A1 WO2022181346A1 PCT/JP2022/005196 JP2022005196W WO2022181346A1 WO 2022181346 A1 WO2022181346 A1 WO 2022181346A1 JP 2022005196 W JP2022005196 W JP 2022005196W WO 2022181346 A1 WO2022181346 A1 WO 2022181346A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- light
- section
- image
- image projection
- projection device
- Prior art date
Links
- 230000003287 optical effect Effects 0.000 claims abstract description 265
- 230000005540 biological transmission Effects 0.000 claims description 6
- 239000004973 liquid crystal related substance Substances 0.000 claims description 6
- 230000000903 blocking effect Effects 0.000 claims description 5
- 238000006243 chemical reaction Methods 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 38
- 238000003384 imaging method Methods 0.000 description 26
- 239000000463 material Substances 0.000 description 22
- 230000004048 modification Effects 0.000 description 17
- 238000012986 modification Methods 0.000 description 17
- 230000000644 propagated effect Effects 0.000 description 8
- 239000011325 microbead Substances 0.000 description 7
- 239000013078 crystal Substances 0.000 description 6
- 238000000034 method Methods 0.000 description 5
- 230000001902 propagating effect Effects 0.000 description 5
- 230000000007 visual effect Effects 0.000 description 5
- 230000001678 irradiating effect Effects 0.000 description 4
- 230000000737 periodic effect Effects 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 238000000151 deposition Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000010408 film Substances 0.000 description 3
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- 229910010413 TiO 2 Inorganic materials 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000000609 electron-beam lithography Methods 0.000 description 2
- 239000000284 extract Substances 0.000 description 2
- 210000003128 head Anatomy 0.000 description 2
- 238000005286 illumination Methods 0.000 description 2
- 238000000206 photolithography Methods 0.000 description 2
- 238000001020 plasma etching Methods 0.000 description 2
- 230000010287 polarization Effects 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000013585 weight reducing agent Substances 0.000 description 2
- 230000003190 augmentative effect Effects 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 210000001525 retina Anatomy 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/01—Head-up displays
- G02B27/0101—Head-up displays characterised by optical features
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/02—Viewing or reading apparatus
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0013—Means for improving the coupling-in of light from the light source into the light guide
- G02B6/0015—Means for improving the coupling-in of light from the light source into the light guide provided on the surface of the light guide or in the bulk of it
- G02B6/0016—Grooves, prisms, gratings, scattering particles or rough surfaces
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0033—Means for improving the coupling-out of light from the light guide
- G02B6/0035—Means for improving the coupling-out of light from the light guide provided on the surface of the light guide or in the bulk of it
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0066—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form characterised by the light source being coupled to the light guide
- G02B6/0068—Arrangements of plural sources, e.g. multi-colour light sources
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0075—Arrangements of multiple light guides
- G02B6/0078—Side-by-side arrangements, e.g. for large area displays
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0081—Mechanical or electrical aspects of the light guide and light source in the lighting device peculiar to the adaptation to planar light guides, e.g. concerning packaging
- G02B6/0086—Positioning aspects
- G02B6/0088—Positioning aspects of the light guide or other optical sheets in the package
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/64—Constructional details of receivers, e.g. cabinets or dust covers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/74—Projection arrangements for image reproduction, e.g. using eidophor
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/12—Picture reproducers
- H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
Definitions
- the present disclosure relates to an image projection device, and more particularly to an image projection device using a diffraction grating.
- instrument panels that light up icons have been used as devices for displaying various types of information in vehicles.
- image display device it has been proposed to embed an image display device in the instrument panel or to configure the entire instrument panel with an image display device.
- HUD Head Up Display
- a wearable HUD that allows light to enter from one end of a light guide plate and extracts light from the other end in the direction of the viewpoint is known (for example, patent See Reference 2).
- a wearable HUD projects an image onto the viewer's retina by directly irradiating the viewer's eye with light emitted from a light source.
- Such a wearable HUD uses a diffraction grating or a half mirror to irradiate the viewer with light from the light source.
- Wearable HUDs project images from the user's point of view when worn on the head, so they can be used in highly immersive virtual reality (VR) and augmented reality (AR). Used.
- VR virtual reality
- AR augmented reality
- an object of the present disclosure is to project a plurality of images at positions with different distances from the viewpoint, and to provide a smaller and lighter image projection device.
- a further object of the present disclosure is to provide a compact and lightweight image projection apparatus by simplifying optical members required for image projection using light of multiple wavelengths.
- the image projection device of the present disclosure is a first image irradiation unit that emits the first light; a first light incident portion into which the first light is incident; an optical waveguide portion that guides a portion of the first light as guided light while totally reflecting the portion; and a portion of the guided light that is emitted in a viewing direction.
- a light guide plate portion having a first light emitting portion; and a diffraction grating section provided in the first light incidence section
- the first light emitting section includes a beam splitter provided inside the optical waveguide, and a retroreflective section provided at an end of the optical waveguide.
- the beam splitter splits the first light to project an image on the screen, and the retroreflecting part retroreflects the first light at the end of the optical waveguide, and can be projected to form an aerial image. This makes it possible to project a plurality of images at positions at different distances from the viewpoint, and to reduce the size and weight of the image projection device.
- the image projection device of the present disclosure is a third image irradiation unit that emits the first light; a fourth image irradiation unit that emits the second light; a third light incident portion into which the first light and the second light are incident; and a portion of the first light and a portion of the second light that are guided as first guided light and second guided light, respectively.
- a light guide plate portion having an optical waveguide portion and a third light emitting portion for emitting the first guided light and the second guided light;
- a first diffraction grating section provided in the third light entrance section, the angles of incidence of the first light and the second light with respect to the first diffraction grating section are different;
- a portion of the first light and a portion of the second light diffracted by the first diffraction grating satisfy the total reflection condition of the optical waveguide.
- the first light and the second light are incident on the first diffraction grating section at different angles of incidence, the first light and the second light are totally reflected by the optical waveguide section, and the third light is generated. Since the light is guided up to the emitting part, it is possible to simplify the optical member and achieve reduction in size and weight.
- FIG. 1 is a schematic cross-sectional view showing the structure of the diffraction grating section 10 in the first embodiment.
- FIG. 2 is a schematic diagram showing the structure of the image projection device according to the first embodiment.
- FIG. 3 is a schematic cross-sectional view showing an enlarged first light emitting portion of the image projection device according to the first embodiment.
- FIG. 4A is a photograph of an image EX projected on the external screen 30 and an aerial image A1 formed in the air by installing a camera at the position of the viewpoint 60.
- the photograph is a photograph in which the camera is focused on the external screen 30.
- FIG. 4B is a photograph of an image EX projected onto the external screen 30 and an aerial image A1 formed in the air by a camera installed at the position of the viewpoint 60.
- FIG. 6A is a photograph of an image EX and an image V1 projected on the external screen 30 and an aerial image A1 formed in the air by installing a camera at the position of the viewpoint 60.
- the focus of the camera on the external screen 30 is shown in FIG.
- FIG. 6B is a photograph of an image EX and an image V1 projected onto the external screen 30 and an aerial image A1 formed in the air by installing a camera at the position of the viewpoint 60.
- the imaging position of the aerial image A1 is shown in FIG.
- FIG. 7 is a schematic diagram showing the structure of an image projection device according to the third embodiment.
- FIG. 8 is a schematic cross-sectional view showing an enlarged first light emitting portion of the image projection device according to the third embodiment.
- FIG. 9A is a photograph of an image EX and an image V1 projected onto the external screen 30 by installing a camera at the position of the viewpoint 60, and aerial images A1 and A2 formed in the air. It is a photograph in which the camera is focused on the image position.
- FIG. 9B is a photograph of an image EX and an image V1 projected on the external screen 30 and aerial images A1 and A2 formed in the air by installing a camera at the position of the viewpoint 60, and the result of the aerial image A2.
- FIG. 10A is a diagram showing beam profiles of aerial images A1 and A2, and is a photograph focused from the viewpoint 60 position.
- FIG. 10B is a diagram showing the beam profiles of the aerial images A1 and A2, showing the three-dimensional brightness profile at the imaging position.
- FIG. 10C is a diagram showing the beam profiles of the aerial images A1 and A2, showing the three-dimensional brightness profile at the imaging position.
- FIG. 10D is a diagram showing beam profiles of aerial images A1 and A2, which are luminance profiles in the x direction.
- FIG. 10E is a diagram showing beam profiles of aerial images A1 and A2, which are luminance profiles in the y direction.
- FIG. 11 is a schematic diagram showing the structure of the image projection device according to the fourth embodiment.
- FIG. 12 is a schematic diagram showing the structure of an image projection device according to a modification of the fourth embodiment.
- FIG. 13 is a schematic diagram showing the structure of the image projection device according to the fifth embodiment.
- FIG. 14 is a schematic diagram showing the structure of an image projection device according to a modification of the fifth embodiment.
- FIG. 15A is a schematic diagram showing a structural example of the retroreflective portion 24 in the sixth embodiment.
- FIG. 15B is a schematic diagram showing a structural example of the retroreflective portion 24 in the sixth embodiment.
- FIG. 15C is a schematic diagram showing a structural example of the retroreflective portion 24 in the sixth embodiment.
- FIG. 16 is a schematic diagram showing the structure of the image projection device according to the ninth embodiment.
- FIG. 17 is a schematic perspective view showing an enlarged light incident portion 22 of the image projection device according to the ninth embodiment.
- FIG. 18A is a photograph showing the path of light when laser light is incident on the light guide plate portion 20, and shows the path of red light.
- FIG. 18B is a photograph showing the path of light when laser light is incident on the light guide plate portion 20, and shows the path of green light.
- FIG. 18C is a photograph showing the path of light when laser light is incident on the light guide plate portion 20, and shows the path when red light and green light are simultaneously incident.
- FIG. 19 is a schematic diagram showing the structure of the image projection device according to the tenth embodiment.
- FIG. 20 is a schematic diagram showing the structure of an image projection device according to a modification of the tenth embodiment.
- FIG. 21 is a schematic diagram showing the structure of the image projection device according to the eleventh embodiment.
- FIG. 22 is a schematic diagram showing the structure of the image projection device according to the twelfth embodiment.
- FIG. 23 is a schematic perspective view showing an enlarged light emitting section 123 of the image projection device according to the twelfth embodiment.
- FIG. 24 is a schematic diagram showing the structure of an image projection device according to the thirteenth embodiment.
- FIG. 25 is a schematic diagram showing the structure of an image projection device according to a modification of the thirteenth embodiment.
- FIG. 26A is a schematic perspective view showing the arrangement of the diffraction grating section 10 and the diffraction grating section 80 in the fourteenth embodiment, showing the diffraction grating section 10.
- FIG. 26B is a schematic perspective view showing the arrangement of the diffraction grating section 10 and the diffraction grating section 80 in the fourteenth embodiment, showing the diffraction grating section 80.
- FIG. FIG. 27 is a schematic diagram showing a structural example of the image irradiation unit 40 of the image projection device according to the fourteenth embodiment.
- FIG. 1 is a schematic cross-sectional view showing the structure of the diffraction grating section 10 in this embodiment.
- the diffraction grating section 10 includes a plate-like portion 11, a plurality of convex portions 12 and a plurality of concave portions 13.
- the flat plate-like portion 11 constitutes a light incident surface.
- the convex portions 12 and the concave portions 13 form periodic repetitions of the refractive index in the in-plane direction in the diffraction grating portion 10 and correspond to the uneven portion in the present disclosure.
- the plate-like portion 11 and the convex portion 12 are integrally formed of the same material. 1 schematically shows the structure of the diffraction grating section 10, and the dimensions and angles in the drawing do not represent the actual dimensions of the diffraction grating section 10.
- the convex portions 12 and the concave portions 13 of the diffraction grating portion 10 are each formed to extend in a stripe shape in the depth direction of the paper surface.
- the convex portion 12 is formed to be inclined by a predetermined angle ⁇ with respect to the main surface of the flat plate portion 11, and constitutes a slant grating.
- the convex portion 12 and the concave portion 13 are covered with a covering portion made of a material having a different refractive index from that of the flat plate portion 11 .
- the material forming the diffraction grating section 10 is not limited, an example of the material forming the plate-shaped section 11 and the convex section 12 is a dielectric having a refractive index of about 2.5 and containing TiO 2 as a main component. Glass or polymer containing SiO 2 as a main component can be used as the covering portion that covers the convex portion 12 and the concave portion 13 .
- the uneven portions of the diffraction grating section 10 can be formed by, for example, photolithography technology, nanoimprint technology, EBL (Electron Beam Lithography) technology, or the like. Further, by holding the covering portion in a tilted state and using a reactive ion etching (RIE) method or the like, the projections 12 and the recesses 13 can be formed by tilting at an angle ⁇ . At this time, the inclination angle ⁇ of the protrusions 12 and the recesses 13 is the angle formed between the main surface of the diffraction grating section 10 and the line connecting the center of the upper end and the lower end of the protrusions 12 .
- FIG. 1 shows a slant grating in which the convex portions 12 and the concave portions 13 are inclined as the uneven portion of the diffraction grating portion 10, it may be a pillar grating perpendicular to the main surface.
- FIG. 1 schematically shows the progress of light in the diffraction grating section 10 using arrows, it does not reflect the exact incident position, travel path, and exit position of the light.
- a laser beam is irradiated toward the diffraction grating section 10 from a light source section (not shown).
- the laser light is coherent light with the same phase, and is irradiated as collimated light by a collimating lens or the like.
- Incident light emitted from the light source portion enters the flat portion 11 at a predetermined inclination angle from the interface of the diffraction grating portion 10 .
- FIG. 1 shows an example in which the inclination angle of incident light and the inclination direction ⁇ of the convex portions 12 and the concave portions 13 in the diffraction grating section 10 are the same direction, but they may be opposite directions.
- a portion of the light incident on the diffraction grating portion 10 travels outward as diffracted light at a predetermined angle due to the periodic refractive index difference between the convex portions 12 and the concave portions 13, and a portion of the light propagates through the plate-like portion as propagating light. 11 as leak propagation light. Leakage light propagating in the flat plate portion 11 is reflected at the interface with the air, reaches the uneven portion again, and is diffracted by the convex portions 12 and the concave portions 13 .
- the 0th order light T1 is transmitted through the covering section and irradiated to the outside.
- the first-order light (-1st-order light T2) diffracted in the direction in which the convex portion 12 is inclined also passes through the covering portion and is irradiated to the outside. This is because the 0th-order light T1 and the -1st-order light T2 are diffracted at an angle nearly perpendicular to the main surface of the diffraction grating section 10, and therefore do not satisfy the conditions for total reflection at the interface between the covering section and the air layer. is.
- the first-order light (+1st-order light I1) diffracted in the direction opposite to the inclination of the convex portion 12 is totally reflected by the interface between the covering portion and the air layer and propagates through the covering portion.
- the secondary light (-2nd order light I2) diffracted in the direction in which the convex portion 12 is inclined is also totally reflected by the interface between the covering portion and the air layer and propagates through the covering portion.
- the conditions for total reflection at the interface between the covering portion and the air layer are determined by the refractive index of the material forming the covering portion.
- the +1st-order light I1 and the ⁇ 2nd-order light I2 that have propagated through total reflection within the covering portion are irradiated to the outside from the ends of the covering portion.
- the 0th-order light T1, ⁇ 1st-order light T2, +1st-order light I1, and ⁇ 2nd-order light I2 are light beams diffracted by the convex portion 12 and the concave portion 13, and therefore travel while the light diameter is slightly expanded. .
- FIG. 2 is a schematic diagram showing the structure of the image projection device according to this embodiment.
- the image projection apparatus includes a diffraction grating section 10, a light guide plate section 20, an external screen 30, and image irradiation sections 40 and 50.
- FIG. 1 A viewer wearing the image projection device views the direction of the light guide plate 20 and the external screen 30 from the position of the viewpoint 60 .
- the diffraction grating section 10 is an optical element including a flat plate portion 11, convex portions 12, concave portions 13, and a covering portion, and is formed separately from the light guide plate portion 20.
- the light guide plate portion 20 is a plate-like member made of a translucent material, and includes an optical waveguide portion 21 , a light incidence portion 22 , a beam splitter 23 and a retroreflection portion 24 .
- the optical waveguide part 21 is a plate-like member made of a translucent material, and light is guided from one end side to the other end side by repeating total reflection of light at the interface with the air. Since light is transmitted from one surface side to the other surface side of the optical waveguide portion 21 , the viewer can visually recognize the direction of the external screen 30 from the viewpoint 60 through the optical waveguide portion 21 .
- the optical waveguide portion 21 has a flat plate shape, but it may have a curved surface shape as long as the light can be propagated by total internal reflection.
- the light incident portion 22 is an inclined surface formed at one end of the optical waveguide portion 21, is arranged adjacent to the diffraction grating portion 10, and corresponds to the first light incident portion in the present disclosure.
- the light entrance section 22 may be provided with an antireflection film or a refractive index adjustment section in order to increase the optical coupling ratio with the diffraction grating section 10 .
- the beam splitter 23 is an optical element that reflects part of the light incident from one surface and transmits the rest. In the example shown in FIG. is formed as A specific configuration of the beam splitter 23 is not limited, and a normal structure and design method can be used.
- the retroreflector 24 is an optical member that reflects incident light while maintaining convergence in the direction of incidence. may have. When the light propagated through the optical waveguide portion 21 is incident on the retroreflecting portion 24, the light is reflected in the direction in which the light is incident. reflected as
- the area between the position where the beam splitter 23 is provided and the end portion where the retroreflecting section 24 is provided in the optical waveguide section 21 is a region where the light propagating in the optical waveguide section 21 is irradiated to the outside. and configures the first light emitting portion in the present disclosure.
- the external screen 30 displays an image by projecting the light emitted from the light guide plate portion 20 as will be described later.
- the material constituting the external screen 30 is not limited, and a translucent material that transmits light may be used, or a white material that blocks and reflects light may be used. When a translucent material is used, images can be superimposed and projected using the external environment of the image projection apparatus as a background.
- the external screen 30 and the arm portion are integrally formed, and the arm portion is fixed to the light guide plate portion 20, thereby maintaining the relative positional relationship between the external screen 30 and the light guide plate portion 20.
- the external screen 30 may be provided separately from the image projection device.
- the image irradiation unit 40 is a device that irradiates the diffraction grating unit 10 with the first light for projecting the first image, and corresponds to the first image irradiation unit in the present disclosure.
- the image irradiation unit 40 irradiates the diffraction grating unit 10 with light through mirrors 45 , 46 , 47 and a bandpass filter 48 .
- the light source unit 41 preferably uses a laser light source, and irradiates an image forming unit (not shown) with laser light emitted from the light source unit 41 to include the first image in the first light.
- a liquid crystal display element, a digital mirror device, or the like can be used as the image forming section, and it may be provided inside the image irradiation section 40 or may be arranged on the optical path to the diffraction grating section 10 .
- the image irradiation unit 40 By providing the image irradiation unit 40 with a liquid crystal display element or a digital mirror device, which is an image forming unit, it is possible to change the content of the first image included in the first light over time and project a moving image. .
- the image irradiation unit 50 is a device that irradiates the diffraction grating unit 10 with the second light for projecting the second image, and corresponds to the second image irradiation unit in the present disclosure.
- the image irradiation section 50 is provided separately from the image irradiation section 40 , and the incident angle of the second light with respect to the diffraction grating section 10 is different from the incident angle of the first light irradiated by the image irradiation section 40 .
- the specific configuration of the image irradiation unit 50 is not limited, and the same configuration as that of the image irradiation unit 40 can be used, but the wavelengths of the first light and the second light are different.
- FIG. 3 is a schematic cross-sectional view showing an enlarged first light emitting portion of the image projection device according to the present embodiment. Solid-line arrows and dashed-line arrows shown in the figure schematically indicate paths of light.
- the first light emitted from the image irradiation unit 40 is reflected by mirrors 45 , 46 and 47 and reaches the diffraction grating unit 10 via the bandpass filter 48 .
- 0th-order light T 1 and +1st-order light I 1 are extracted as diffracted light according to the incident angle of the first light, and enter the light incident section 22 .
- the first light incident on the light incident portion 22 from the diffraction grating portion 10 is totally reflected in the optical waveguide portion 21 and propagates as guided light.
- the incident angle of the first light incident on the light incident portion 22 from the diffraction grating section 10 to the light incident portion 22 is determined by diffraction conditions.
- the light incident portion 22 is inclined so that any one of the 0th order light T1, the ⁇ 1st order light T2, the +1st order light I1 and the ⁇ 2nd order light I2 satisfies the total reflection condition on both surfaces of the optical waveguide portion 21 . angle is set.
- Part of the first light propagated as guided light while being totally reflected in the optical waveguide section 21 is reflected by one surface of the beam splitter 23 and the rest is transmitted through the beam splitter 23 .
- the guided light reflected by the beam splitter 23 is taken out in the direction of the external screen 30 as the irradiation light LE, and the image EX is projected onto the external screen 30 .
- the reflectance of one surface of the beam splitter 23 to be low, it is possible to suppress the intensity of the irradiation light LE and make the image EX invisible.
- the guided light transmitted through the beam splitter 23 is totally reflected again by the optical waveguide section 21, reaches the retroreflective section 24, and is retroreflected.
- the guided light retroreflected by the retroreflection portion 24 travels in the opposite direction in the optical waveguide portion 21, is totally reflected, reaches the beam splitter 23, is reflected, and is reflected as the imaging light L1 in the direction of the viewpoint 60. taken out.
- the guided light propagated through the optical waveguide section 21 has an enlarged light diameter, but the guided light reflected by the retroreflective section 24 travels with a reduced light diameter.
- the light diameter reaches the beam splitter 23 while being further reduced.
- the imaging light L1 that is reflected by the beam splitter 23 and travels in the direction of the viewpoint 60 is focused at a predetermined position, and an aerial image A1 is formed in the air.
- the retroreflection portion 24 is formed with a flat surface, the optical path length from the diffraction grating portion 10 to the retroreflection portion 24 is the same as the optical path length from the retroreflection portion 24 to the aerial image A1.
- the imaging light L1 is incident on the viewpoint 60 while its light diameter is expanding.
- the viewer can view the aerial image A1 formed in the air and the image EX projected on the external screen 30 at the same time by viewing the optical waveguide 21 and the external screen 30 from the viewpoint 60. .
- the other end of the optical waveguide portion 21 is formed in a convex shape and the retroreflective portion 24 is formed in a concave shape, but the other end is formed in a flat plate shape or a concave shape.
- the retroreflective portion 24 may be flat or convex.
- the guided light propagating in the optical waveguide section 21 needs to be totally reflected at the interface with air at least once before reaching the retroreflective section 24 from the beam splitter 23 .
- the irradiation light LV is taken out as irradiation light LV.
- the region of the optical waveguide section 21 from which the irradiation light LV is extracted corresponds to the second light emitting section in the present disclosure.
- the irradiation light LV extracted from the second light emitting portion reaches the external screen 30 and projects an image V1 (not shown).
- the viewpoint direction, which is the traveling direction of the imaging light L1 and the external screen direction, which is the traveling direction of the illumination light LV are substantially parallel. Accordingly, even if the distance between the external screen 30 and the optical waveguide section 21 is changed, the projected position of the image V1 on the external screen 30 does not change. Therefore, when the viewer views the direction of the external screen 30 from the viewpoint 60, the position where the aerial image A1 is formed and the position where the image V1 is projected do not overlap, and the aerial image A1 and the image V1 are projected within the same visual field. It becomes possible to visually recognize V1 side by side.
- the direction of the viewpoint and the direction of the external screen are parallel is shown, but they may be in a direction in which the two intersect at a predetermined angle.
- the projection position of the image V1 on the external screen 30 can be adjusted. Visual recognition at the viewpoint 60 becomes possible.
- Part of the light diffracted by the diffraction grating 10 of the second light emitted from the image irradiation unit 50 also satisfies the condition of total reflection in the optical waveguide 21, so that the image EX is projected similarly to the first light. and aerial image A1 can be formed.
- the second light diffracted by the diffraction grating section 10 that does not satisfy the condition of total reflection in the optical waveguide section 21 can be used to project the image V1.
- the second light diffracted by the diffraction grating section 10 may not satisfy the total reflection condition at the optical waveguide section 21, and only the image V1 may be projected onto the external screen 30 with the second light. .
- the area through which the irradiation light LV for projecting the image V1 is transmitted corresponds to the second light emitting portion of the optical waveguide portion 21 .
- FIG. 4A, 4B, 4C, and 4D are photographs of an image EX projected onto the external screen 30 and an aerial image A1 formed in the air by installing a camera at the viewpoint 60 position.
- FIG. 4A is a photograph in which the camera is focused on the external screen 30, and
- FIG. 4B is a photograph in which the camera is focused on the imaging position of the aerial image A1.
- the photographs on the left show how it looks in a bright state with the room light turned on, and the photographs on the right show how it looks in a dark state with the room light turned off.
- the image EX and the aerial image A1 are shown at positions indicated by white-lined ellipses in the photograph. As shown in FIG.
- the image EX is difficult to see in a bright environment and visible in a dark environment. Also, as shown in FIG. 4B, the aerial image A1 is visible in both bright and dark environments. In addition, the aerial image A1 and the image EX can be viewed closely in the same field of view, and the viewer can select an object to be viewed simply by adjusting the visual focal length.
- the first light is split by the beam splitter 23 to project the image EX on the external screen 30, and the retroreflection section 24 at the end of the optical waveguide section 21 projects the first light.
- the first light is retroreflected, and the beam splitter 23 reflects the first light in the direction of the viewpoint to form an aerial image A1.
- the diffraction grating section 10 is provided in the light incident section 22 of the light guide plate section 20, and the beam splitter 23 and the retroreflecting section 24 are provided to form the first light emitting section, complicated optical design and an increase in the number of parts are required. It is unnecessary, and it becomes possible to achieve miniaturization and weight reduction.
- FIG. 5 is a schematic cross-sectional view showing an enlarged first light emitting portion of the image projection device according to the present embodiment.
- the solid-line arrows and broken-line arrows shown in FIG. 5 schematically show paths of light.
- the area hatched with oblique lines in FIG. 5 indicates the area irradiated with the irradiation light LV.
- the image projection apparatus of this embodiment differs from that of the first embodiment only in the projection position of the image V1, and the rest of the configuration is the same as that of the first embodiment described with reference to FIG.
- the second light emitted from the image irradiation unit 50 is used as the irradiation light LV, and the external screen direction, which is the traveling direction of the irradiation light LV, intersects the viewpoint direction, and the image EX and the image V1 are formed in the same area. is projected onto
- the light that propagates after being totally reflected inside the optical waveguide section 21 is split by the beam splitter 23 to project the image EX onto the external screen 30 as the irradiation light LE. Further, the light transmitted through the beam splitter 23 is totally reflected again by the optical waveguide section 21 and reaches the retroreflection section 24. After being retroreflected, the light is reflected by the beam splitter 23 to form an aerial image A1 as the imaging light L1. image.
- the traveling direction of the irradiation light LV projected onto the external screen 30 from the second light emitting portion is a direction that intersects with the viewpoint direction, which is the traveling direction of the imaging light L1.
- the second light emitted from the image irradiation unit 50 does not enter the diffraction grating unit 10 and is directly irradiated as the irradiation light LV onto the external screen 30 via the optical waveguide unit 21.
- An image V1 is projected onto the external screen 30 .
- 6A and 6B are photographs of an image EX and an image V1 projected on the external screen 30 and an aerial image A1 formed in the air by installing a camera at the viewpoint 60 position.
- 6A shows the camera focused on the external screen 30, and
- FIG. 6B shows the camera focused on the imaging position of the aerial image A1.
- the image EX and the aerial image A1 are captured at the positions indicated by white-lined ellipses in the photograph, and the image V1 is captured in a larger range than the image EX.
- the image EX is superimposed on the image V1 and displayed, and both can be visually recognized at the same time. Also, the viewer can select an object to visually recognize only by adjusting the focal length of vision.
- the image V1 is projected over a wide range of the external screen 30 using the second light as the irradiation light LV, so it is possible to perform image projection in which the image V1 is used as a background image and superimposed on the aerial image A1.
- the projection positions of the image V1, which is the background image, and the image EX have the same distance from the viewpoint 60, so that the viewer can view two different images V1 and A1 at the same time.
- the image EX can be visually recognized.
- FIG. 7 is a schematic diagram showing the structure of the image projection device according to this embodiment.
- the image projection device includes a diffraction grating section 10, a light guide plate section 20, an external screen 30, and image irradiation sections 40 and 50.
- a viewer wearing the image projection device views the direction of the light guide plate 20 and the external screen 30 from the position of the viewpoint 60 .
- the diffraction grating section 10 is an optical element including a flat plate portion 11, convex portions 12, concave portions 13, and a covering portion, and is formed separately from the light guide plate portion 20.
- the light guide plate portion 20 is a plate-like member made of a translucent material, and includes an optical waveguide portion 21 , a light incident portion 22 , a beam splitter 23 , a retroreflection portion 24 , and a partial reflection portion 25 . I have.
- the partial reflection section 25 is an optical element that reflects part of the light with a predetermined reflectance and transmits the rest of the light, and is provided on the optical path between the beam splitter 23 and the retroreflection section 24 .
- a partial reflection portion 25 is formed between the end portion of the optical waveguide portion 21 and the retroreflection portion 24 .
- 7 shows an example in which the end portion of the optical waveguide portion 21, the retroreflecting portion 24, and the partial reflecting portion 25 are formed in a flat shape. and a convex mirror. Alternatively, a combination of three-dimensional parabolic concave-convex shapes may be used.
- FIG. 8 is a schematic cross-sectional view showing an enlarged first light emitting portion of the image projection device according to this embodiment.
- Solid-line arrows and broken-line arrows shown in FIG. 8 schematically indicate paths of light.
- the area hatched with oblique lines in FIG. 8 indicates the area irradiated with the irradiation light LV.
- the first light emitted from the image irradiation section 40 or the second light emitted from the image irradiation section 50 enters the optical waveguide section 21 from the light incident section 22 and is guided as guided light. The light is guided while being totally reflected by the wave portion 21 .
- the guided light reflected by the beam splitter 23 is taken out as irradiation light LE to the external screen 30 and projects an image EX on the external screen 30 .
- the guided light that has passed through the beam splitter 23 is reflected by the partial reflection portion 25 and the retroreflection portion 24, then re-enters the beam splitter 23 and is reflected, and is taken out in the direction of the viewpoint 60 as the imaging light beams L1 and L2.
- the light reflected by the partial reflection portion 25 is specular reflection
- the guided light propagated while expanding the light diameter in the optical waveguide portion 21 is reflected by the beam splitter 23 and reaches the viewpoint 60. It progresses while the light diameter expands.
- the aerial image A2 appears to be formed in the space between the optical waveguide section 21 and the external screen 30.
- the light transmitted through the partial reflection portion 25 is incident on the retroreflection portion 24, where the guided light is retroreflected and reflected by the beam splitter 23 until it reaches the viewpoint 60 while the light diameter is reduced. proceed.
- the aerial image A1 is visually recognized as if it were formed in the space between the optical waveguide section 21 and the viewpoint 60.
- the traveling direction of the irradiation light LV projected onto the external screen 30 from the second light emitting portion is a direction that intersects with the viewing direction, which is the traveling direction of the imaging lights L1 and L2. projected on top.
- 9A, 9B, and 9C are photographs of an image EX and an image V1 projected on the external screen 30 and aerial images A1 and A2 formed in the air by installing a camera at the position of the viewpoint 60.
- 9A focuses the camera on the imaging position of the aerial image A1
- FIG. 9B focuses the camera on the imaging position of the aerial image A2
- FIG. 9C focuses the camera on the external screen 30.
- Aerial images A1 and A2 and image EX are shown at positions indicated by white-lined ellipses in the photograph, and image V1 is shown in a larger range than image EX.
- the aerial image A1 can be clearly captured.
- FIG. 9B by focusing between the optical waveguide section 21 and the external screen 30, the aerial image A2 can be clearly captured.
- the image EX and the image V1 can be clearly captured.
- the aerial images A1 and A2 the image EX and the image V1 can be closely viewed in the same field of view, and the viewer can select an object to be viewed simply by adjusting the visual focal length.
- FIGS. 10A, 10B, 10C, 10D, and 10E are diagrams showing beam profiles of aerial images A1 and A2.
- FIG. 10A is a photograph focused from the viewpoint 60 position.
- 10B and 10C show three-dimensional luminance profiles at imaging positions.
- FIG. 10D is the luminance profile in the x direction.
- FIG. 10E is the luminance profile in the y direction.
- FIGS. 10A and 10B show enlarged regions surrounded by white lines in FIGS. 9A and 9B, respectively.
- FIGS. 10C to 10E show the measurement results of brightness at the imaging positions of the aerial images A1 and A2, respectively.
- "x direction” and "y direction” shown in FIGS. 10A, 10B, 10C, 10D, and 10E indicate the x-axis direction and y-axis direction shown in FIG. 9C.
- the aerial image A1 is formed as an elliptical shape elongated in the x-axis direction
- the aerial image A2 is formed as an elliptical shape elongated in the y-axis direction.
- the half-value width in the x-axis direction of the aerial image A1 was about 31 pixels
- the half-value width in the y-axis direction was about 10 pixels.
- the half-value width in the x-axis direction of the aerial image A2 was about 20 pixels
- the half-value width in the y-axis direction was about 25 pixels. Therefore, the aerial images A1 and A2 are formed into different shapes, and the shape visually recognized when the viewer changes the visual focal length changes between the aerial images A1 and A2.
- guided light specularly reflected by the partial reflection portion 25 at the end of the optical waveguide portion 21 forms an aerial image A2, and is retroreflected by the retroreflection portion 24 to form the aerial image A2.
- An aerial image A1 is formed by wave light.
- the image EX and the image V1 are projected onto the external screen 30 . This makes it possible to project and visually recognize a plurality of images at positions at different distances from the viewpoint.
- the diffraction grating section 10 is provided in the light entrance section 22 of the light guide plate section 20, and the beam splitter 23, the partial reflection section 25, and the retroreflection section 24 are provided to constitute the first light emission section, complicated optical design and There is no need to increase the number of parts, and it is possible to reduce the size and weight.
- FIG. 11 is a schematic diagram showing the structure of the image projection device according to this embodiment.
- two light guide plate portions 20 are provided, and a common diffraction grating portion 10 is arranged to face the light incident portion 22 provided in each light guide plate portion 20 .
- the image projection device includes one diffraction grating section 10, two light guide plate sections 20, an external screen 30, and image irradiation sections 40 and 50.
- a viewer wearing the image projection device views the direction of the light guide plate 20 and the external screen 30 with both eyes from two viewpoints 60 .
- the diffraction grating section 10 is an optical element including a flat plate portion 11, convex portions 12, concave portions 13, and a covering portion, and is formed separately from the light guide plate portion 20.
- the light guide plate portion 20 is a plate-like member made of a translucent material, and includes an optical waveguide portion 21, a light incident portion 22, a beam splitter 23, and a retroreflection portion 24, respectively.
- the two light guide plate portions 20 are arranged so that the light incident portions 22 are adjacent to each other, and the common diffraction grating portion 10 is arranged across the two light incident portions 22 so as to face each other. Further, the first light is incident on the diffraction grating section 10 from one image irradiation section 40 , and the first light diffracted by the diffraction grating section 10 is transmitted from the light incident section 22 of each light guide plate section 20 into the optical waveguide section 21 . incident on Each of the two light guide plate portions 20 has a flat plate shape and is arranged in a V shape.
- the first light is diffracted by the concave and convex portions formed by the convex portions 12 and the concave portions 13, and the 0th order light T1 and the +1st order light I1 travel rightward in the drawing.
- the -1st order light T2 and the -2nd order light I2 travel leftward in the drawing. Therefore, the 0th-order light T1 and the +1st-order light I1 are incident on the optical waveguide section 21 arranged to face the right half of the diffraction grating section 10, and the optical waveguide section 21 arranged to face the left half of the diffraction grating section 10.
- the -1st order light T2 and the -2nd order light I2 are incident on the wave portion 21 .
- the first light (guided light) guided through the two light guide plate portions 20 is reflected by the beam splitter 23 and the retroreflecting portion 24 provided on the other end side, respectively, and is taken out in the direction of the viewpoint 60 to be aerial light.
- Image A1 is formed.
- an aerial image A2 can also be formed.
- the image irradiation unit 50 can directly irradiate the external screen 30 with the irradiation light LV via the light guide plate unit 20, and project the image V1 over a wide area on the external screen 30.
- FIG. 11 shows a state in which the irradiation light LV emitted from the image irradiation unit 50 is projected on the left half of the external screen 30, but by using an optical member such as a separate lens, the entire external screen 30 can be irradiated. It is also possible to illuminate the light LV and project the image V1 over the entire external screen 30 so as to cover the entire field of view.
- the image projection apparatus of the present embodiment by providing the diffraction grating unit 10 common to the two light guide plate units 20, the formation of the aerial images A1 and A2 is visually recognized by both eyes of the viewer. be able to. Further, by projecting the image V1, which is a background image, onto the external screen 30 with the irradiation light LV emitted by the image irradiation unit 50, the aerial images A1 and A2 can be superimposed and projected on the image V1. Also, the image projection apparatus of this embodiment does not require complicated optical design or an increase in the number of parts, and can be reduced in size and weight.
- FIG. 12 is a schematic diagram showing the structure of an image projection device according to a modification of the fourth embodiment. This modified example differs from the fourth embodiment in that the light guide plate portion 20 has a curved shape.
- the inclination angle of the light incident portion 22 and the shape of the optical waveguide portion 21 so that the zero-order light T1 satisfies the total reflection condition of the optical waveguide portion 21 arranged on the right side, The zero-order light T1 is guided as guided light.
- the inclination angle of the light incident part 22 and the shape of the optical waveguide part 21 so that the -1st order light T2 satisfies the total reflection condition of the optical waveguide part 21 arranged on the left side, the -1st order light T2 is guided as guided light.
- the aerial images A1 and A2 formed in the air from two viewpoints 60 and the image V1 projected on the external screen 30 can be viewed.
- the two light guide plate portions 20 have a curved surface shape along the direction of the viewpoint 60, but the incident angle of the first light from the diffraction grating portion 10 to the light incident portion 22 is Since it is determined by the diffraction conditions, it is possible to design the light guide plate section 20 so as to repeat total reflection along the curved surface.
- the left and right light guide plate portions 20 are drawn in a line-symmetrical shape. 22 may be different on the left and right.
- the optical waveguide part 21 has a curved surface shape, the degree of freedom in designing the image projection device is improved, and it is possible to improve the design and the comfort when wearing it.
- FIG. 13 is a schematic diagram showing the structure of the image projection device according to this embodiment.
- the image projection device includes a diffraction grating section 10, a light guide plate section 20, an external screen 30, and image irradiation sections 40 and 50.
- FIG. A viewer wearing the image projection device views the direction of the light guide plate 20 and the external screen 30 from the position of the viewpoint 60 .
- the diffraction grating section 10 is an optical element that includes a flat plate portion 11, convex portions 12, concave portions 13, and a covering portion, and is formed separately from the light guide plate portion 20.
- the light guide plate portion 20 is a plate-shaped member made of a translucent material, and includes an optical waveguide portion 21 , a light incident portion 22 , a beam splitter 23 , a retroreflection portion 24 , and a partial reflection portion 25 . , with an optical filter 26 .
- a second light emitting portion from which the second light emitted from the image irradiating portion 50 is extracted is provided with an optical filter 61, an optical shutter portion 62, and a projection lens 63. As shown in FIG.
- the optical filters 26 and 61 are optical members that transmit light in a predetermined wavelength range and block light in other wavelengths.
- the optical filter 26 a bandpass filter that blocks the wavelength of the second light and transmits the wavelength of the first light, or an optical filter equivalent thereto is used.
- the optical filter 61 a band-pass filter that blocks the wavelength of the first light and transmits the wavelength of the second light, or an optical filter corresponding thereto is used.
- the first light emitted by the image irradiation unit 40 is red light
- the second light emitted by the image irradiation unit 50 is green light. Therefore, the optical filter 26 may use a long-pass filter and the optical filter 61 may use a short-pass filter.
- the optical shutter section 62 is an optical member driven and controlled by a control section (not shown) to switch between transmission and blocking of light.
- a specific configuration of the optical shutter unit 62 is not limited, and a liquid crystal shutter or the like can be used.
- the projection lens 63 is an optical member that enlarges the light diameter of the irradiation light LV extracted from the second light emitting portion and projects it onto the external screen 30 . Although one lens is shown as the projection lens 63 in FIG. 13, the projection lens 63 may be configured by combining a plurality of lenses.
- the first light emitted from the image irradiation unit 40 part of the light diffracted by the diffraction grating unit 10 enters from the light incidence unit 22, is totally reflected in the optical waveguide unit 21, and is guided as guided light. be.
- the guided light of the first light reaches the beam splitter 23 while being totally reflected, and is partially reflected to project the image EX on the external screen 30 .
- the light that has passed through the beam splitter 23 is totally reflected again and reaches the end of the optical waveguide section 21 .
- the guided light of the first light that has reached the end of the optical waveguide section 21 passes through the optical filter 26 and enters the partial reflection section 25 . to reach The guided light is retroreflected by the retroreflector 24 .
- the first light retroreflected by the retroreflector 24 forms an aerial image A1 in the air between the viewpoint 60 and the optical waveguide 21 as described in the first embodiment.
- the light specularly reflected by the partial reflection portion 25 forms an aerial image A2 in the air between the optical waveguide portion 21 and the external screen 30 .
- Light that does not satisfy the condition of total reflection in the optical waveguide section 21 in the first light is extracted from the second light emitting section toward the external screen 30 , and the second light emitting section is provided with an optical filter 61 . Therefore, the first light is blocked by the optical filter 61 and is not projected onto the external screen 30 .
- the incident angle of the second light with respect to the diffraction grating section 10 is made different from the incident angle of the first light, and by selecting the incident angle that satisfies the appropriate diffraction conditions, the first light and the second light are guided.
- the angles of incidence on wave section 21 can be set to be the same. Further, if the incident positions of the first light and the second light to the diffraction grating section 10 are the same, the paths of the first light and the second light guided by total reflection in the optical waveguide section 21 should be the same. can be done.
- the guided light of the second light also reaches the beam splitter 23 while being totally reflected, and is partially reflected to project the image EX on the external screen 30 .
- the light that has passed through the beam splitter 23 is totally reflected again and reaches the end of the optical waveguide section 21 .
- the guided light of the second light that has reached the end of the optical waveguide portion 21 is blocked by the optical filter 26 and does not reach the partial reflection portion 25 and the retroreflection portion 24 . Therefore, the second light reflected back to the beam splitter 23 disappears, and the aerial images A1 and A2 are not formed by the second light.
- the light that does not satisfy the condition of total reflection in the optical waveguide section 21 is extracted from the second light emitting section toward the external screen 30, and when the optical shutter section 62 is in the transmission state, the projection lens 63 is used.
- the external screen 30 is irradiated with the irradiation light LV through the projection screen 30, and the image V1 is projected.
- the light shutter section 62 is in the blocking state, the irradiation light LV of the second light is blocked and the image V1 is not projected.
- the optical filter 26 is provided between the beam splitter 23 and the retroreflector 24, so that the aerial images A1 and A2 can be formed using only the first light. Further, by providing the optical filter 61 in the second light emitting portion, it is possible to project the image V1 on the external screen 30 only with the second light. Therefore, the contents of the aerial images A1 and A2 formed by the first light emitted from the image irradiation section 40 and the contents of the image V1 projected by the second light emitted from the image irradiation section 50 can be made different. It is possible to realize various image projections.
- the imaging efficiency of the aerial images A1 and A2 can be improved by including a lens optical unit with a variable focal length in the image irradiation unit 40 and adjusting the divergence angle of the first light incident on the diffraction grating unit 10. It can also be changed.
- FIG. 14 is a schematic diagram showing the structure of an image projection device according to a modification of the fifth embodiment.
- the image projection device includes a diffraction grating section 10, a light guide plate section 20, an external screen 30, and image irradiation sections 40a, 40b and 50.
- FIG. 14 is a schematic diagram showing the structure of an image projection device according to a modification of the fifth embodiment.
- the image projection device includes a diffraction grating section 10, a light guide plate section 20, an external screen 30, and image irradiation sections 40a, 40b and 50.
- the image irradiation unit 40a irradiates the first light of the first wavelength containing the first image
- the image irradiation unit 40b irradiates the second light of the second wavelength containing the second image.
- the image irradiation unit 50 irradiates the third light of the third wavelength containing the third image.
- the first wavelength is red light
- the second wavelength is blue light
- the third wavelength is green light.
- a notch filter that blocks the third wavelength and transmits the first and second wavelengths is used as the optical filter 26
- a band filter that blocks the first and second wavelengths and transmits the third wavelength is used as the optical filter 61.
- a dichroic mirror selective reflection section that reflects the first wavelength and transmits the second wavelength is used as the partial reflection section 25 .
- the incident angles of the first light, the second light, and the third light irradiated onto the diffraction grating section 10 from the image irradiation sections 40a, 40b, and 50 are selected so as to satisfy appropriate diffraction conditions, and the diffraction grating section 10
- the light incident on the optical waveguide portion 21 from the optical waveguide portion 21 is totally reflected along the same path and propagates through the optical waveguide portion 21 .
- Part of the light diffracted by the diffraction grating section 10 enters from the light incident section 22 and is totally reflected inside the optical waveguide section 21 of the first light and the second light emitted from the image irradiating sections 40a and 40b. Waveguided as guided light.
- the guided light of the first light and the second light reaches the beam splitter 23 while being totally reflected, and is partially reflected to project the image EX on the external screen 30 .
- the light that has passed through the beam splitter 23 is totally reflected again and reaches the end of the optical waveguide section 21 .
- the guided light of the first light that has reached the end of the optical waveguide portion 21 is transmitted through the optical filter 26, enters the partial reflection portion 25, and is specularly reflected.
- the first light specularly reflected by the partial reflection portion 25 forms an aerial image A2 in the air between the optical waveguide portion 21 and the external screen 30 .
- the guided light of the second light that has reached the end of the optical waveguide section 21 passes through the optical filter 26 and the partial reflection section 25, enters the retroreflection section 24, and is retroreflected.
- the second light retroreflected by the retroreflector 24 forms an aerial image A1 in the air between the viewpoint 60 and the optical waveguide 21 as described in the first embodiment.
- the light that does not satisfy the condition of total reflection in the optical waveguide section 21 is extracted from the second light emitting section toward the external screen 30, and the second light emitting section includes an optical filter 61. Therefore, the first light and the second light are blocked by the optical filter 61 and are not projected onto the external screen 30 .
- the guided light of the third light also reaches the beam splitter 23 while being totally reflected, and is partially reflected to project the image EX on the external screen 30 .
- the light that has passed through the beam splitter 23 is totally reflected again and reaches the end of the optical waveguide section 21 .
- the guided light of the third light that has reached the end of the optical waveguide section 21 is blocked by the optical filter 26 and does not reach the partial reflection section 25 and the retroreflection section 24 . Therefore, there is no third light reflected back to the beam splitter 23, and the aerial images A1 and A2 are not formed by the third light.
- the light that does not satisfy the condition of total reflection in the optical waveguide section 21 is extracted from the second light emitting section toward the external screen 30, and when the optical shutter section 62 is in the transmission state, the projection lens 63
- the external screen 30 is irradiated with the irradiation light LV through the projection screen 30, and the image V1 is projected.
- the light shutter section 62 is in the blocking state, the irradiation light LV of the second light is blocked and the image V1 is not projected.
- the optical filter 26 between the beam splitter 23 and the retroreflector 24, it is possible to form the aerial images A1 and A2 with the first light and the second light, respectively. can. Further, by providing the optical filter 61 in the second light emitting portion, it is possible to project the image V1 on the external screen 30 only with the third light. Therefore, the contents of the aerial images A1 and A2 formed by the first light and the second light emitted from the image irradiation section 40 and the contents of the image V1 projected by the third light emitted from the image irradiation section 50 By changing , various image projections can be realized.
- FIGS. 15A, 15B, and 15C are schematic diagrams showing structural examples of the retroreflective portion 24 in this embodiment. As shown in FIGS. 15A, 15B, and 15C, the retroreflective portion 24 has microbeads selectively formed on a sheet portion 24a. A regular reflection region 24c in which is exposed is mixedly formed.
- the sheet portion 24a is a thin plate-like member whose surface is formed as a reflective surface. It is preferable that the sheet portion 24a has flexibility.
- the sheet portion 24a is flexible, so that it can be formed into the flat plate shape shown in FIG. 15A, the concave mirror shown in FIG. 15B, or the convex mirror shown in FIG. 15C. can take the form of
- the retroreflective area 24b is an area in which microbeads are formed on the surface of the sheet portion 24a.
- the light incident on the retroreflective area 24b is retroreflected in the incident direction by being reflected within the microbeads.
- Microbeads are not formed in the specular reflection region 24c, and the reflective surface of the sheet portion 24a is exposed. Therefore, light incident on the specular reflection region 24c is specularly reflected by the reflecting surface of the sheet portion 24a.
- the retroreflective portion 24 of this embodiment is formed by forming a mask on the specular reflection region 24c of the sheet portion 24a using a photolithography technique, and depositing microbeads on the region where the mask is not formed to form the retroreflective region 24b.
- part of the light incident on the retroreflective portion 24 while increasing in light diameter is retroreflected as imaging light L1 in the retroreflective region 24b, and the light diameter is reduced. and reflected.
- the light is retroreflected as the imaging light L2, and the light diameter is enlarged and reflected.
- the retroreflector 24 is a flat plate, a concave mirror, or a convex mirror, the light diameters of the imaging lights L1 and L2 are enlarged or reduced. can be adjusted.
- the retroreflective portion 24 of the present embodiment By using the retroreflective portion 24 of the present embodiment, the guided light that has reached the end portion of the optical waveguide portion 21 is partially re-reflected and the rest is specularly reflected, as shown in FIG. 8 in the third embodiment.
- Aerial images A1 and A2 can be formed in the same manner as the object.
- the sheet portion 24a is a thin plate-like member and has flexibility as described above.
- the retroreflection efficiency can be designed by adjusting the arrangement and purity of the microbeads on the surface of the sheet portion 24a.
- the sheet portion 24a by depositing a metal thin film on the surface of the sheet portion 24a, it is possible to construct a reflective retroreflective element or a retroreflective optical filter in which reflection and retroreflection are mixed. By using these structures for the seat portion 24a, it is possible to improve the degree of freedom in optical design and the design.
- the wavelength of the first light emitted from the image irradiation unit 40 is used as it is for the projection of the image EX and the image V1 and the formation of the aerial images A1 and A2.
- the image EX and the image V1 can be projected in a color different from that of the light emitted from the image irradiation unit 40. and aerial images A1 and A2 may be formed.
- the concave-convex portion of the diffraction grating section 10 does not need to have a periodic structure, and may have a holographic grating structure as long as it can diffract light in at least two directions.
- the diffraction grating section 10 may be formed inside the optical waveguide section 21 or on the surface of the light incident section 22 .
- FIG. 16 is a schematic diagram showing the structure of the image projection device according to this embodiment.
- the image projection device includes a diffraction grating section 10, a light guide plate section 20, and image irradiation sections 40a, 40b, and 40c.
- the light guide plate section 20 includes an optical waveguide section 21 , a light entrance section 22 , a light exit section 123 , an optical filter 31 and an optical shutter section 32 .
- the diffraction grating section 10 corresponds to the first diffraction grating section in the present disclosure.
- the light incident portion 22 is an inclined surface formed at one end of the optical waveguide portion 21, is arranged adjacent to the diffraction grating portion 10, and corresponds to the third light incident portion in the present disclosure.
- the light entrance section 22 may be provided with an antireflection film or a refractive index adjustment section in order to increase the optical coupling ratio with the diffraction grating section 10 .
- the light emitting portion 123 is an inclined surface formed at the other end of the optical waveguide portion 21 (the end portion opposite to the light incident portion 22), and corresponds to the third light emitting portion in the present disclosure.
- the inclined surface of the light emitting portion 123 is set at an angle such that the light propagating through the optical waveguide portion 21 is not totally reflected at the light emitting portion 123 .
- the surface of the light emitting section 123 may be provided with an antireflection film or an antireflection structure.
- the optical filter 31 is an optical member that transmits light in a predetermined wavelength range and blocks light in other wavelengths.
- a band-pass filter is used that blocks light of a predetermined wavelength and transmits light of other wavelengths.
- the optical shutter section 32 is an optical member driven and controlled by a control section (not shown) to switch between transmission and blocking of light.
- a specific configuration of the optical shutter unit 32 is not limited, and a liquid crystal shutter or the like can be used.
- the image irradiation units 40a, 40b, and 40c are devices for irradiating the diffraction grating unit 10 with the first light, the second light, and the third light for projecting the first image, the second image, and the third image, respectively. be.
- the image irradiation units 40a and 40b respectively correspond to a third image irradiation unit and a fourth image irradiation unit in the present disclosure.
- the image irradiation units 40a, 40b, and 40c are provided as separate structures, and the incident angles of the first light, the second light, and the third light with respect to the diffraction grating unit 10 are different.
- the wavelengths of the first light, the second light, and the third light are different. For example, the first light is red light, the second light is green light, and the third light is blue light.
- the image irradiation units 40a, 40b, and 40c irradiate the diffraction grating unit 10 with light through mirrors, bandpass filters, and the like.
- the light source unit preferably uses a laser light source, and an image forming unit (not shown) is irradiated with laser light emitted from the light source unit to form the first image, the second image, and the third image into the first light, the second light, and the third image. Include in the third light.
- a liquid crystal display element, a digital mirror device, or the like can be used as the image forming section, and it may be provided inside the image irradiation sections 40 a , 40 b , and 40 c , or may be arranged on the optical path to the diffraction grating section 10 .
- FIG. 17 is a schematic perspective view showing an enlarged light incident portion 22 of the image projection device according to this embodiment.
- a dashed arrow shown in FIG. 17 indicates the path of the first light LR, a two-dot chain line indicates the path of the second light LG, and a one-dot chain line indicates the path of the third light LB.
- the first light LR, the second light LG, and the third light LB emitted from the image irradiation units 40a, 40b, and 40c reach the diffraction grating unit 10 at different incident angles.
- 0th-order light T1, ⁇ 1st-order light T2, +1st-order light I1, and ⁇ 2nd-order light I2 are taken out as diffracted light according to the incident angles of the first light, the second light, and the third light. , enter the light entrance portion 22 .
- the incident angle of the diffracted light incident on the light incident portion 22 from the diffraction grating portion 10 to the light incident portion 22 is determined by the diffraction conditions, the 0th order light T1, ⁇ 1st order light T2, +1st order light I1 and The inclination angle of the light incident portion 22 is set so that any one of the -secondary light I2 satisfies the total reflection condition on both surfaces of the optical waveguide portion 21 .
- the first light LR and the second light LG are arranged so that the +1st order light I1 of each of the first light LR, the second light LG and the third light LB is incident on the light incident portion 22 at the same angle.
- the incident angle of the third light LB to the diffraction grating section 10 is set.
- the diffracted lights of the first light LR, the second light LG, and the third light LB diffracted by the diffraction grating section 10 those that satisfy the total reflection condition of the optical waveguide section 21 are totally reflected within the optical waveguide section 21 . propagates as guided light.
- the first guided light, the second guided light, and the third guided light enter the optical waveguide section 21 from the same position of the light incident section 22, travel at the same angle, and travel at the same position. Since the total reflection is repeated at the position, the light reaches the same position of the light emitting section 123 along the same path.
- the incident position of the first guided light at the light incident portion 22, the incident position of the second guided light at the light incident portion 22, and the incident position of the third guided light at the light incident portion 22 are substantially the same.
- the reflection position in the optical waveguide section 21 of the first guided light, the reflection position in the optical waveguide section 21 of the second guided light, and the reflection position in the optical waveguide section 21 of the third guided light are substantially the same.
- the output position of the first guided light in the light output section 123, the output position of the second guided light in the light output section 123, and the output position of the third guided light in the light output section 123 are substantially the same.
- the first guided light, the second guided light, and the third guided light that have reached the light emitting portion 123 are irradiated from the light emitting portion 123 to the outside, and project the first image, the second image, and the third image, respectively.
- the first guided light, the second guided light, and the third guided light reach the light emitting section 123 along the same path and angle in the optical waveguide section 21, and the first image and the third guided light are obtained.
- the second image and the third image are irradiated from the light emitting section 123 at the same angle. Therefore, the first image, the second image, and the third image are superimposed and projected on the same position on the screen, and a color image using red light, green light, and blue light can be projected.
- the image of the display content indicating a warning is projected in red
- the image of the display content to give a calm atmosphere or a refreshing feeling is projected in blue or green. It is also possible to obtain a color psychology effect, such as by projecting with
- the diffracted light that does not satisfy the total reflection condition in the optical waveguide section 21 is emitted from the fourth light emitting section of the optical waveguide section 21.
- the fourth light emitting portion is provided with the optical filter 31
- only the light of the wavelength selected from the first light LR, the second light LG, and the third light LB is transmitted through the optical filter 31. is removed to the outside.
- the optical shutter section 32 is in the transmission state, the light transmitted through the optical filter 31 is irradiated to the outside and an image is projected.
- the optical shutter section 32 is in the blocked state, the light transmitted through the optical filter 31 is blocked by the optical shutter section 32 and no image is projected.
- the fourth light emitting portion is provided with the optical filter 31 and the optical shutter portion 32 to select the light emitted from the fourth light emitting portion to the outside. All of the first light LR, the second light LG, and the third light LB may be emitted to the outside from the fourth light emitting section without providing the shutter section 32 .
- FIG. 16 shows an example in which the light emitting portion 123 has a flat surface, the light emitting portion 123 is formed in a concave shape or a convex shape to function as a lens so that the first light LR, the second light LG, The spread angle of the third light LB may be adjusted.
- FIGS. 18A and 18B are photographs showing paths of light when laser light is incident on the light guide plate portion 20.
- FIG. FIG. 18A shows the path of red light.
- FIG. 18B shows the path of green light.
- FIG. 18C shows paths when red light and green light are incident simultaneously.
- the bright lines in FIGS. 18A and 18B indicate the path of the light, and the laser light reaches from the light entrance portion 22 to the light exit portion 123 by repeating total reflection at the interface of the optical waveguide portion 21 .
- the incident positions and incident angles of the red light and the green light in the light incident portion 22 are the same, and the paths in the optical waveguide portion 21 are also overlapped.
- the first light LR, the second light LG, and the third light LB are made incident on the diffraction grating section 10 at different angles of incidence, and the first light LR and the second light LG Since the third light LB is totally reflected by the optical waveguide section 21 and guided to the light emitting section 123, the optical members can be simplified, and the size and weight can be reduced. In addition, since the light emitted from the light emitting portion 123 is emitted from the same position and at the same angle, it is not necessary to align the optical axes of the optical members even when light beams of a plurality of wavelengths are superimposed.
- the emission position of each light in the light emission section 123 may shift.
- the optical path of each light may be adjusted according to the shape and size of the light guide plate section 20 . Also, the optical paths may be adjusted in consideration of the possibility that the lights may optically interfere with each other. Further, it is also possible to irradiate the light that does not satisfy the total reflection condition in the optical waveguide section 21 to the outside from the fourth light emitting section to perform various image projections.
- FIG. 19 is a schematic diagram showing the structure of the image projection device according to this embodiment.
- the solid-line arrows and broken-line arrows shown in FIG. 19 schematically show paths of light.
- the area hatched with oblique lines in FIG. 19 indicates the area irradiated with the irradiation light LW.
- two light guide plate portions 20 are provided, and a common diffraction grating portion 10 is arranged to face the light incident portion 22 provided in each light guide plate portion 20 .
- the image projection device includes one diffraction grating section 10, two light guide plate sections 20, an image irradiation section 40, and an external screen 160.
- a viewer wearing the image projection device views the direction of the light guide plate 20 and the external screen 160 with both eyes from two viewpoints 70 .
- the diffraction grating section 10 is an optical element including a flat plate portion 11, convex portions 12, concave portions 13, and a covering portion, and is formed separately from the light guide plate portion 20.
- the light guide plate portion 20 is a plate-like member made of a translucent material, and includes an optical waveguide portion 21, a light incident portion 22, and a light emitting portion 123, respectively.
- the external screen 160 displays an image by projecting the light emitted from the light guide plate section 20 .
- the material constituting the external screen 160 is not limited, and a translucent material that transmits light may be used, or a white material that blocks and reflects light may be used. When a translucent material is used, images can be superimposed and projected using the external environment of the image projection apparatus as a background.
- FIG. 19 shows an example in which the external screen 160 is provided separately from the image projection device. By fixing, the relative positional relationship between the external screen 160 and the light guide plate section 20 may be maintained.
- the two light guide plate portions 20 are arranged so that the light incident portions 22 are adjacent to each other, and the common diffraction grating portion 10 is arranged across the two light incident portions 22 so as to face each other. Also, the two light guide plate portions 20 are flat plates and arranged in a V shape.
- the image irradiation units 40a, 40b, and 40c of the ninth embodiment are collectively shown as the image irradiation unit 40.
- the diffraction grating section 10 is irradiated at an angle.
- the plurality of image irradiation units included in the image irradiation unit 40 respectively correspond to the third image irradiation unit and the fourth image irradiation unit in the present disclosure.
- the first light LR, the second light LG, and the third light LB are incident on the diffraction grating section 10 from the image irradiation section 40, and the first light LR, the third light, and The diffracted lights of the second light LG and the third light LB enter the optical waveguide section 21 from the light incident section 22 of each light guide plate section 20 .
- the first light is diffracted by the concave and convex portions formed by the convex portions 12 and the concave portions 13, and the 0th order light T1 and the +1st order light I1 travel rightward in the figure.
- the -1st order light T2 and the -2nd order light I2 travel leftward in the drawing. Therefore, the 0th-order light T1 and the +1st-order light I1 are incident on the optical waveguide section 21 arranged to face the right half of the diffraction grating section 10, and the optical waveguide section 21 arranged to face the left half of the diffraction grating section 10.
- the -1st order light T2 and the -2nd order light I2 are incident on the wave portion 21 .
- the inclination angle of the light incident portion 22 and the shape of the optical waveguide portion 21 so that the zero-order light T1 satisfies the total reflection condition of the optical waveguide portion 21 arranged on the right side, The zero-order light T1 is guided as guided light.
- the inclination angle of the light incident part 22 and the shape of the optical waveguide part 21 so that the -1st order light T2 satisfies the total reflection condition of the optical waveguide part 21 arranged on the left side, the -1st order light T2 is guided as guided light.
- the first guided light, the second guided light, and the third guided light guided in the two light guide plate portions 20 are irradiated as the irradiation light LW from the respective light emitting portions 123, and the first image, the second image, and the A projection image is displayed by superimposing the third image on the external screen 160 .
- the projection image can be visually recognized with both eyes of the viewer. Further, in the image projection apparatus of this embodiment as well, it is possible to simplify the optical members and reduce the size and weight.
- FIG. 20 is a schematic diagram showing the structure of an image projection device according to a modification of the tenth embodiment.
- the solid-line arrows and broken-line arrows shown in FIG. 20 schematically indicate paths of light.
- This modification differs from the tenth embodiment in that two light guide plate portions 20 have curved surfaces.
- the two light guide plate portions 20 have curved surfaces along the direction of the viewpoint 70, but the incident angle of the first light from the diffraction grating portion 10 to the light incident portion 22 is the diffraction condition , it is possible to design the light guide plate portion 20 so as to repeat total reflection along the curved surface.
- the left and right light guide plate portions 20 are drawn in a shape close to line symmetry. Depending on whether the diffracted light is guided light or not, the inclination angle of the light incident part 22 may be different between the left and right sides.
- FIG. 21 is a schematic diagram showing the structure of the image projection device according to this embodiment. Solid-line arrows and broken-line arrows shown in FIG. 21 schematically indicate paths of light.
- the image projection apparatus of this embodiment includes a diffraction grating section 10, a light guide plate section 20, an image irradiation section 40, a digital mirror device 71, and a reflection mirror section 72.
- FIG. A viewer wearing the image projection device visually recognizes the direction of the reflecting mirror section 72 from the viewpoint position.
- the image projection device of this embodiment is a wearable HUD in the shape of eyeglasses, and uses the light guide plate section 20 as a temple of the eyeglasses and the reflecting mirror section 72 as a lens. Although only the left half is shown in FIG. 21, images can be projected to both eyes by providing a similar structure symmetrically.
- the digital mirror device 71 has a plurality of micromirrors, and each micromirror can individually change the angle of reflection. It is a member that reflects light.
- the reflecting mirror section 72 is a member that guides the light including the image reflected by the digital mirror device 71 and reflects the light in the viewing direction.
- FIG. 21 shows a part of the spectacle lens as the reflecting mirror section 72, but the shape and position are not limited as long as the light from the digital mirror device 71 can be reflected toward the viewpoint.
- the image irradiation unit 40 includes a laser light source that irradiates the first light LR, the second light LG, and the third light LB, and makes each light incident on the diffraction grating unit 10 at different incident angles.
- a digital mirror device 71 which is an image forming unit, is provided separately from the image irradiation unit 40, and an image is included in the light emitted from the light guide plate unit 20.
- An image forming unit may be provided.
- the plurality of laser light sources included in the image irradiation section 40 respectively correspond to the third image irradiation section and the fourth image irradiation section in the present disclosure.
- the first light LR, the second light LG, and the third light LB emitted from the image irradiation unit 40 are incident on the diffraction grating unit 10 at different incident angles, and part of the diffracted light is incident on the diffraction grating unit 10. They enter the optical waveguide section 21 at the same angle from the same position on the section 22 . Moreover, the diffracted lights of the first light LR, the second light LG, and the third light LB satisfy the total reflection condition of the optical waveguide section 21 , and are repeatedly totally reflected within the optical waveguide section 21 to reach the light emitting section 123 . reach.
- the guided light reaching the light emitting portion 123 is emitted from the light guide plate portion 20 and reflected by the digital mirror device 71 .
- the minute mirrors included in the digital mirror device 71 have their reflection angles controlled based on the image information, and the light reflected by the digital mirror device 71 includes an image.
- the light reflected by the digital mirror device 71 is re-reflected in the direction of the viewpoint by the reflecting mirror section 72, and an image is projected onto the viewpoint.
- the first light LR, the second light LG, and the third light LB are totally reflected in the light guide plate portion 20 at the same position and angle, and thus emitted from the light emitting portion 123.
- the irradiation light is reflected by the digital mirror device 71 and the reflection mirror section 72 and reaches the viewpoint along the same path. Therefore, the first image, the second image, and the third image included in the first light LR, the second light LG, and the third light LB are superimposed and incident on the viewpoint, and a color image can be visually recognized.
- time-division driving for image display by the digital mirror device 71
- the timing of light irradiation and image formation of each color is synchronized, and the contents of the first image, the second image, and the third image are made different. be able to.
- PWM Pulth Width Modulation
- the first light LR, the second light LG, and the third light LB are made incident on the diffraction grating section 10 at different angles of incidence, and the first light LR, the second light LG, Since the third light LB is totally reflected by the optical waveguide section 21 and guided to the light emitting section 123, it is possible to simplify the optical members and reduce the size and weight.
- the light emitted from the light emitting portion 123 is emitted from the same position and at the same angle, it is not necessary to align the optical axes of the optical members even when light beams of a plurality of wavelengths are superimposed.
- FIG. 22 is a schematic diagram showing the structure of the image projection device according to this embodiment.
- the image projection device includes a diffraction grating section 10, a light guide plate section 20, image irradiation sections 40a and 40b, an image irradiation section 50, an external screen 160, and a diffraction grating section 80.
- a viewer wearing the image projection device visually recognizes the direction of the light guide plate 20 and the external screen 160 from the position of the viewpoint.
- the diffraction grating section 80 corresponds to the second diffraction grating section in the present disclosure.
- the diffraction grating sections 10 and 80 are optical elements having a plate-like portion 11, convex portions 12, concave portions 13, and covering portions, and are formed separately from the light guide plate portion 20.
- the light guide plate portion 20 is a plate-like member made of a translucent material, and includes an optical waveguide portion 21, a light incident portion 22, a light emitting portion 123, an optical filter 31, and an optical shutter portion 32. , a projection lens 33 .
- the image irradiation unit 50 is a device that irradiates the diffraction grating unit 10 with light for projecting an image, and is provided as a separate structure from the image irradiation units 40a and 40b.
- the wavelengths of the first light and second light emitted by the image irradiation units 40a and 40b and the third light emitted by the image irradiation unit 50 are different.
- the first light is red light and the second light is blue light.
- the light, the third light is green light.
- the diffracted light diffracted by the diffraction grating section 10 of the third light emitted by the image irradiation section 50 does not satisfy the total reflection condition of the light guide plate section 20 .
- Part of the light diffracted by the diffraction grating section 10 among the first light and the second light emitted by the image irradiation sections 40 a and 40 b satisfies the total reflection condition of the light guide plate section 20
- the third light irradiated from the image irradiation unit 50 is diffracted by the diffraction grating unit 10, passes through the optical waveguide unit 21, is irradiated onto the external screen 160 as irradiation light LV, and projects a projected image onto the external screen 160.
- the projection lens 33 is an optical member for enlarging the light diameter of the irradiation light LV extracted from the second light emitting section and projecting it onto the external screen 160 . Although one lens is shown as the projection lens 33 in FIG. 22, the projection lens 33 may be configured by combining a plurality of lenses.
- the 22 shows a state in which the irradiation light LV emitted from the image irradiation unit 50 is projected on the left half of the external screen 160, but by using an optical member such as a separate lens, the light can be projected onto the entire external screen 160. It is also possible to illuminate the illumination light LV and project the image across the external screen 160 so as to cover the entire field of view.
- FIG. 23 is a schematic perspective view showing an enlarged light emitting section 123 of the image projection device according to this embodiment.
- the diffraction grating section 80 is arranged in the light emitting section 123, and is an optical member that opens the waveguided light emitted from the light emitting section 123 and extracts it to the outside.
- the convex portions 12 and concave portions 13 of the diffraction grating portion 80 have the same shape as that of the diffraction grating portion 10, and the uneven portions of the diffraction grating portion 10 and the diffraction grating portion 80 are parallel to each other.
- the projections 12 and the recesses 13 are placed in In the diffraction grating section 10, the projections 12 and the recesses 13 are arranged so as to face the light entrance section 22, but in the diffraction grating section 80, the flat plate portion 11 is arranged so as to face the light exit section 123. .
- the first light and the second light that have entered the optical waveguide section 21 are totally reflected at the same position in the optical waveguide section 21 at the same angle and reach the light emitting section 123 .
- a diffraction grating section 80 is provided in the light emitting section 123, and the first light and the second light are diffracted by the diffraction grating section 80 to form third and fourth output diffracted lights at different diffraction angles. taken out in the viewing direction.
- the guided light that has propagated through the optical waveguide section 21 is diffracted by the diffraction grating section 80 and is taken out as imaging light in the direction of the viewpoint while the light diameter increases.
- the diffracted lights of the first light and the second light diffracted by the diffraction grating section 80 travel with their light diameters increasing until they reach the viewpoint.
- the aerial images A1 and A2 appear to be formed in the space between the diffraction grating section 80 and the external screen 160 .
- the planes forming the aerial images A1 and A2 are tilted and non-parallel to each other according to the angles of the first and second outgoing diffracted lights, as shown in FIG.
- the aerial images A1 and A2 are formed circumferentially around the diffraction grating section 80, and a plurality of aerial images A1 and A2 can be arranged and displayed in a dome shape.
- the image V1 projected on the external screen 160 by the irradiation light LV from the second light emitting section and the image formed by the imaging lights L1 and L2 are formed.
- the aerial images A1 and A2 can be visually recognized at the same time.
- the structures of the diffraction grating section 10 and the diffraction grating section 80 are the same.
- the imaging direction and imaging position may be set to appropriate positions.
- part of the first light and part of the second light are respectively diffracted by the diffraction grating section 80 provided in the light emitting section 123 to produce third and fourth emitted diffracted light and fourth emitted diffracted light.
- the light is irradiated in the viewing direction at different emission angles.
- the aerial images A1 and A2 can be formed at different angles and positions with the third and fourth emitted diffracted lights.
- the third light from the image irradiation section 50 can be projected from the fourth light emission section onto the external screen 160, and the image V1 and the aerial images A1 and A2 can be superimposed and visually recognized.
- the first light and the second light are made incident on the diffraction grating section 10 at different angles of incidence, and the first light and the second light are totally reflected by the optical waveguide section 21. Since the light is guided up to the light emitting portion 123, it is possible to simplify the optical member and reduce the size and weight.
- FIG. 24 is a schematic diagram showing the structure of the image projection device according to this embodiment. Solid-line arrows and broken-line arrows shown in FIG. 24 schematically indicate paths of light. In addition, the area hatched with oblique lines in FIG. 24 indicates the area irradiated with the irradiation light LV.
- two curved light guide plate portions 20 are provided, and a common diffraction grating portion 10 is arranged facing the light incident portion 22 provided in each of the light guide plate portions 20 .
- the image projection device includes one diffraction grating section 10, two light guide plate sections 20, an image irradiation section 40, an image irradiation section 50, an external screen 160, and a diffraction grating section 80. ing. A viewer wearing the image projection device views the direction of the light guide plate 20 and the external screen 160 with both eyes from two viewpoints 70 .
- the inclination angle of the light incident portion 22 and the shape of the optical waveguide portion 21 so that the +1st-order light I1 satisfies the total reflection condition of the optical waveguide portion 21 arranged on the right side, The +1st order light I1 is guided as guided light.
- the inclination angle of the light incident part 22 and the shape of the optical waveguide part 21 so that the -2nd order light I2 satisfies the total reflection condition of the optical waveguide part 21 arranged on the left side, the -2nd order light I2 is guided as guided light.
- the first light and the second light guided in the two light guide plate portions 20 are diffracted by the diffraction grating portions 80 provided in the respective light emitting portions 123, and the third emitted diffracted light and the fourth emitted diffracted light , and form aerial images A1 and A2.
- the third light emitted from the image irradiation unit 50 is emitted to the external screen 160 as irradiation light LV to project an image.
- the two light guide plate portions 20 are provided with the common diffraction grating portion 10, and the light exit portion 123 is provided with the diffraction grating portion 80.
- the aerial images A1 and A2 can be visually recognized by pressing. Further, in the image projection apparatus of this embodiment as well, it is possible to simplify the optical members and reduce the size and weight.
- FIG. 25 is a schematic diagram showing the structure of an image projection device according to a modification of the thirteenth embodiment.
- the solid-line arrows and broken-line arrows shown in FIG. 25 schematically show paths of light.
- the hatched area in FIG. 25 indicates the area irradiated with the irradiation light LV.
- two flat plate-shaped light guide plate portions 20 are provided, and a common diffraction grating portion 10 is arranged so as to face the light incident portion 22 provided in each of the light guide plate portions 20 .
- the image projection device includes one diffraction grating section 10, two light guide plate sections 20, an image irradiation section 40, an image irradiation section 50, an external screen 160, and a diffraction grating section 80. ing. A viewer wearing the image projection device views the direction of the light guide plate 20 and the external screen 160 with both eyes from two viewpoints 70 .
- the inclination angle of the light incident portion 22 and the shape of the optical waveguide portion 21 so that the zero-order light T1 satisfies the total reflection condition of the optical waveguide portion 21 arranged on the right side, The zero-order light T1 is guided as guided light.
- the inclination angle of the light incident part 22 and the shape of the optical waveguide part 21 so that the -1st order light T2 satisfies the total reflection condition of the optical waveguide part 21 arranged on the left side, the -1st order light T2 is guided as guided light.
- the first light and the second light guided in the two light guide plate portions 20 are diffracted by the diffraction grating portions 80 provided in the respective light emitting portions 123, and the first emitted diffracted light and the second emitted diffracted light , and form aerial images A1 and A2.
- the third light emitted from the image irradiation unit 50 is emitted to the external screen 160 as irradiation light LV to project an image.
- the two light guide plate portions 20 are provided with a common diffraction grating portion 10, and the light exit portion 123 is provided with a diffraction grating portion 80, so that both eyes of the viewer can
- the aerial images A1 and A2 can be visually recognized by pressing.
- FIGS. 26A and 26B are schematic perspective views showing the arrangement of the diffraction grating section 10 and the diffraction grating section 80 in the embodiment.
- FIG. 26A shows the diffraction grating section 10.
- FIG. 26B shows the diffraction grating section 80.
- FIG. FIG. 27 is a schematic diagram showing a structural example of the image irradiation unit 40 of the image projection device according to this embodiment.
- the uneven portions of the diffraction grating portion 10 are along the x-axis direction (the vertical direction in the drawing), and the uneven portions of the diffraction grating portion 80 are along the y-axis direction (the horizontal direction in the drawing). , and are arranged such that the uneven portions are orthogonal to each other.
- the first light LR and the second light LB incident on the diffraction grating section 10 have different angles with respect to the z-axis in the yz plane, and are incident on the diffraction grating section 10 at different incident angles.
- the diffracted lights of the first light LR and the second light LB in the diffraction grating section 10 are diffracted in the same direction, and the first light LR and the second light LB are diffracted in the optical waveguide section 21.
- LB propagates through total internal reflection on the same path.
- the guided lights of the first light LR and the second light LB that have propagated through the optical waveguide section 21 are incident on the same position of the diffraction grating section 80 provided in the light emitting section 123 at the same angle. Since the response portion of the diffraction grating section 80 extends along the y-axis direction, the first light LR and the second light LB diffracted by the diffraction grating section 80 are separated in the xz plane and travel in the viewing direction. Aerial images A1 and A2 are separately formed in the vertical direction.
- the image irradiation unit 40 includes a light source unit 41, a second beam splitter 142, polarizers 43a and 43b, a chopper 144, lenses 145 and 147, an aperture 146, mirrors M1 and M2. , M3. It is preferable that the light source unit 41 uses a laser light source.
- the laser light emitted from the light source unit 41 is split by the second beam splitter 142, one enters the polarizer 43a, the other is reflected by the mirror M1 and enters the polarizer 43b, and the changing directions are orthogonal to each other. adjusted to The laser light incident on the polarizers 43 a and 43 b passes through the chopper 144 .
- the chopper 144 By passing the laser light through the chopper 144, when one laser light passes, the other laser light is blocked, and the light is switched on/off complementarily. That is, the polarization direction of each laser beam is maintained even after passing through the chopper 144 .
- the two laser beams are coaxially overlapped in the multiplexing section, the beam diameter and the spread angle are adjusted through the lens 145, the aperture 146, and the lens 147, and the beam is reflected by the mirror M3 and emitted to the outside. .
- the aerial images A1 and A2 are vertically divided and formed. be able to.
Abstract
Description
第1光を照射する第1画像照射部と、
前記第1光が入射される第1光入射部と、前記第1光の一部を全反射しながら導波光として導波する光導波部と、前記導波光の一部を視点方向に出射する第1光出射部を有する導光板部と、
前記第1光入射部に設けられた回折格子部と、を備え、
前記第1光出射部は、前記光導波部内に設けられたビームスプリッターと、前記光導波部の端部に設けられた再帰反射部を備える。
第1光を照射する第3画像照射部と、
第2光を照射する第4画像照射部と、
前記第1光および前記第2光が入射される第3光入射部と、前記第1光の一部および前記第2光の一部をそれぞれ第1導波光および第2導波光として導波する光導波部と、前記第1導波光および前記第2導波光を出射する第3光出射部を有する導光板部と、
前記第3光入射部に設けられた第1回折格子部を備え、
前記第1回折格子部に対する前記第1光と前記第2光の入射角度が異なっており、
前記第1回折格子部で回折された前記第1光の一部および前記第2光の一部が前記光導波部の全反射条件を満たす。
以下、本開示の実施の形態について、図面を参照して詳細に説明する。各図面に示される同一または同等の構成要素、部材、処理には、同一の符号を付すものとし、適宜重複した説明は省略する。図1は、本実施形態における回折格子部10の構造を示す模式断面図である。図1に示すように回折格子部10は、平板状部分11と、複数の凸部12と複数の凹部13を備えている。平板状部分11は、光入射面を構成する。凸部12および凹部13は、回折格子部10において面内方向において周期的な屈折率の繰り返しを構成し、本開示における凹凸部分に相当している。平板状部分11と凸部12は同一の材料で一体に形成されている。なお図1は、回折格子部10の構造を模式的に示したものであり、図中の寸法や角度は回折格子部10における実寸を示すものではない。
次に、本開示の第2実施形態について図5、図6を用いて説明する。第1実施形態と重複する内容は説明を省略する。図5は、本実施形態に係る画像投影装置の第1光出射部を拡大して示す模式断面図である。図5中に示した実線矢印および破線矢印は、光の経路を模式的に示すものである。また、図5中に斜線でハッチングを施した領域は照射光LVが照射される領域を示している。本実施形態の画像投影装置は、画像V1の投影位置のみが第1実施形態と異なっており、他の構成は第1実施形態で図1を用いて説明したものと同様である。本実施形態では、画像照射部50から照射される第2光を照射光LVとして、照射光LVの進行方向である外部スクリーン方向を視点方向と交差させて、画像EXと画像V1とを同じ領域に投影するものである。
次に、本開示の第3実施形態について図7から図10を用いて説明する。第1実施形態と重複する内容は説明を省略する。本実施形態では、第1光出射部を構成するビームスプリッター23と再帰反射部24の間に、所定の反射率で導波光の一部を反射して残りを透過する部分反射部を設けた点が第1実施形態と異なっている。図7は、本実施形態に係る画像投影装置の構造を示す模式図である。
次に、本開示の第4実施形態について図11を用いて説明する。第1実施形態と重複する内容は説明を省略する。図11は、本実施形態に係る画像投影装置の構造を示す模式図である。本実施形態では、導光板部20を二つ備えて、それぞれの導光板部20に設けられた光入射部22に対向して共通の回折格子部10が配置されている。
次に、本開示の第4実施形態の変形例について図12を用いて説明する。第1実施形態と重複する内容は説明を省略する。図12は、第4実施形態の変形例に係る画像投影装置の構造を示す模式図である。本変形例では、導光板部20が曲面形状を有している点が第4実施形態と異なっている。
次に、本開示の第5実施形態について図13、図14を用いて説明する。第1実施形態と重複する内容は説明を省略する。図13は、本実施形態に係る画像投影装置の構造を示す模式図である。図13に示すように、画像投影装置は回折格子部10と、導光板部20と、外部スクリーン30と、画像照射部40,50とを備えている。画像投影装置を装着する視聴者は、視点60の位置から導光板部20および外部スクリーン30方向を視認する。
次に、本開示の第5実施形態の変形例について図14を用いて説明する。第1実施形態と重複する内容は説明を省略する。図14は、第5実施形態の変形例に係る画像投影装置の構造を示す模式図である。図14に示すように、画像投影装置は回折格子部10と、導光板部20と、外部スクリーン30と、画像照射部40a,40b,50とを備えている。
次に、本開示の第6実施形態について図15A、図15B、図15Cを用いて説明する。第1実施形態と重複する内容は説明を省略する。図15A、図15B、図15Cは、本実施形態における再帰反射部24の構造例を示す模式図である。図15A、図15B、図15Cに示すように、再帰反射部24は、シート部24a上に選択的にマイクロビーズが形成されており、マイクロビーズが形成された再帰反射領域24bと、シート部24aが露出した正反射領域24cが混在して形成されている。
次に、本開示の第7実施形態について説明する。第1実施形態と重複する内容は説明を省略する。第1実施形態から第6実施形態までは、画像照射部40から照射された第1光をそのままの波長で画像EX、画像V1の投影およびエアリアルイメージA1,A2の結像に用いていた。しかし、第1光出射部または第2光出射部に第1光の波長を変換する波長変換部を設けることで、画像照射部40から照射された光と異なる色で画像EX、画像V1の投影およびエアリアルイメージA1,A2の結像を行うとしてもよい。
次に、本開示の第8実施形態について説明する。第1実施形態と重複する内容は説明を省略する。第1実施形態から第7実施形態までは、回折格子部10として周期的な凹凸部を備えたグレーティングを用いていた。しかし、回折格子部10の凹凸部が周期構造である必要はなく、少なくとも二つの方向に光を回折することができれば、ホログラフィックグレーティング構造であってもよい。また、回折格子部10を導光板部20と別体に形成した例を示したが、光導波部21内部や光入射部22の表面に回折格子部10を形成するとしてもよい。
図16は、本実施形態に係る画像投影装置の構造を示す模式図である。図16に示すように画像投影装置は、回折格子部10と、導光板部20と、画像照射部40a,40b,40cを備えている。導光板部20は、光導波部21と、光入射部22と、光出射部123と、光フィルター31と、光シャッター部32を備えている。回折格子部10は、本開示のおける第1回折格子部に相当する。
次に、本開示の第10実施形態について図19を用いて説明する。第9実施形態と重複する内容は説明を省略する。図19は、本実施形態に係る画像投影装置の構造を示す模式図である。図19中に示した実線矢印および破線矢印は、光の経路を模式的に示すものである。また、図19中に斜線でハッチングを施した領域は照射光LWが照射される領域を示している。本実施形態では、導光板部20を二つ備えて、それぞれの導光板部20に設けられた光入射部22に対向して共通の回折格子部10が配置されている。
次に、本開示の第10実施形態の変形例について図20を用いて説明する。第9実施形態と重複する内容は説明を省略する。図20は、第10実施形態の変形例に係る画像投影装置の構造を示す模式図である。図20中に示した実線矢印および破線矢印は、光の経路を模式的に示すものである。本変形例では、二つの導光板部20が曲面形状を有している点が第10実施形態と異なっている。
次に、本開示の第11実施形態について図21を用いて説明する。第9実施形態と重複する内容は説明を省略する。図21は、本実施形態に係る画像投影装置の構造を示す模式図である。図21中に示した実線矢印および破線矢印は、光の経路を模式的に示すものである。図21に示すように、本実施形態の画像投影装置は、回折格子部10と、導光板部20と、画像照射部40と、デジタルミラーデバイス71と、反射ミラー部72を備えている。画像投影装置を装着する視聴者は、視点位置から反射ミラー部72方向を視認する。本実施形態の画像投影装置は眼鏡形状のウェアラブル型HUDであり、導光板部20を眼鏡のテンプルとして用い、反射ミラー部72をレンズとしている。図21では左半分のみを示しているが、左右対称に同様の構造を備えることで、両眼に対して画像を投影することができる。
次に、本開示の第12実施形態について図22,図23を用いて説明する。第9実施形態と重複する内容は説明を省略する。図22は、本実施形態に係る画像投影装置の構造を示す模式図である。図22に示すように画像投影装置は、回折格子部10と、導光板部20と、画像照射部40a,40bと、画像照射部50と、外部スクリーン160と、回折格子部80を備えている。画像投影装置を装着する視聴者は、視点の位置から導光板部20および外部スクリーン160方向を視認する。回折格子部80は、本開示における第2回折格子部に相当する。
次に、本開示の第13実施形態について図24を用いて説明する。第9実施形態と重複する内容は説明を省略する。図24は、本実施形態に係る画像投影装置の構造を示す模式図である。図24中に示した実線矢印および破線矢印は、光の経路を模式的に示すものである。また、図24中に斜線でハッチングを施した領域は照射光LVが照射される領域を示している。本実施形態では、曲面形状の導光板部20を二つ備えて、それぞれの導光板部20に設けられた光入射部22に対向して共通の回折格子部10が配置されている。
次に、本開示の第13実施形態の変形例について図25を用いて説明する。第9実施形態と重複する内容は説明を省略する。図25は、第13実施形態の変形例に係る画像投影装置の構造を示す模式図である。図25中に示した実線矢印および破線矢印は、光の経路を模式的に示すものである。また、図25中に斜線でハッチングを施した領域は照射光LVが照射される領域を示している。本実施形態では、平板状の導光板部20を二つ備えて、それぞれの導光板部20に設けられた光入射部22に対向して共通の回折格子部10が配置されている。
次に、本開示の第14実施形態について図26A、図26Bを用いて説明する。本実施形態は、回折格子部80の配置が第12実施形態と異なっており、第12実施形態と重複する内容は説明を省略する。図26A、26Bは、実施形態における回折格子部10と回折格子部80の配置を示す模式斜視図である。図26Aは回折格子部10を示している。図26Bは回折格子部80を示している。図27は、本実施形態に係る画像投影装置の画像照射部40の構造例を示す模式図である。
次に、本開示の第15実施形態について説明する。第9実施形態と重複する内容は説明を省略する。第9実施形態から第14実施形態では、回折格子部10,80を構成する材料としてTiO2とSiO2を挙げたが、非線形光学結晶を用いて第二次高調波発生素子(SHG:Second harmonic generation)等の波長変換素子を構成するとしてもよい。非線形光学結晶の材料としては、例えばKTP結晶、LBO結晶、CLBO結晶等が挙げられる。
Claims (24)
- 第1光を照射する第1画像照射部と、
前記第1光が入射される第1光入射部と、前記第1光の一部を全反射しながら導波光として導波する光導波部と、前記導波光の一部を視点方向に出射する第1光出射部を有する導光板部と、
前記第1光入射部に設けられた回折格子部と、を備え、
前記第1光出射部は、前記光導波部内に設けられたビームスプリッターと、前記光導波部の端部に設けられた再帰反射部を備える画像投影装置。 - 請求項1に記載の画像投影装置であって、
前記導光板部は、前記回折格子部で分岐された光の一つを透過して前記視点方向とは異なる外部スクリーン方向に出射する第2光出射部を備える画像投影装置。 - 請求項2に記載の画像投影装置であって、
前記視点方向と前記外部スクリーン方向とは、略平行である画像投影装置。 - 請求項2または3に記載の画像投影装置であって、
光の透過と遮断を切り替える光シャッター部が、前記第1光出射部または前記第2光出射部に設けられている画像投影装置。 - 請求項2から4の何れか一項に記載の画像投影装置であって、
前記第1光の波長を変換する波長変換部が、前記第1光出射部または前記第2光出射部に設けられている画像投影装置。 - 請求項1から5の何れか一項に記載の画像投影装置であって、
前記再帰反射部は、光を正反射する正反射領域と再帰反射する再帰反射領域が混在して形成されている画像投影装置。 - 請求項1から5の何れか一項に記載の画像投影装置であって、
前記導波光の一部を反射して残りを透過する部分反射部が、前記ビームスプリッターと前記再帰反射部の間に設けられている画像投影装置。 - 請求項1から7の何れか一項に記載の画像投影装置であって、
第2光を前記回折格子部に対して照射する第2画像照射部を備え、
前記回折格子部に対する前記第1光と前記第2光の入射角度が異なっており、
前記光導波部は、前記第2光の一部を全反射しながら導波光として導波する画像投影装置。 - 請求項8に記載の画像投影装置であって、
前記第1光の波長を反射し前記第2光の波長を透過する選択反射部が、前記ビームスプリッターと前記再帰反射部の間に設けられている画像投影装置。 - 請求項8または9に記載の画像投影装置であって、
前記第1光の波長または前記第2光の波長を選択的に遮断する光フィルターが、第2光出射部に設けられている画像投影装置。 - 請求項1から10の何れか一項に記載の画像投影装置であって、
二つの前記導光板部を備え、
前記導光板部のそれぞれの前記第1光入射部に、一つの前記回折格子部が共通に設けられている画像投影装置。 - 請求項1から11の何れか一項に記載の画像投影装置であって、
前記光導波部が曲面形状を有する画像投影装置。 - 請求項1から12の何れか一項に記載の画像投影装置であって、
前記第1画像照射部は、液晶表示素子またはデジタルミラーデバイスを備え、前記第1光に含まれる第1画像の内容を経時的に変化させる画像投影装置。 - 請求項1から13の何れか一項に記載の画像投影装置であって、
前記回折格子部は、光入射面を構成する平板状部分と、前記平板状部分と一体に構成された凹凸部分を備え、前記導光板部とは別体に形成されている画像投影装置。 - 請求項1から13の何れか一項に記載の画像投影装置であって、
前記回折格子部は、少なくとも二つの方向に光を回折するホログラフィックグレーティングを有する画像投影装置。 - 第1光を照射する第3画像照射部と、
第2光を照射する第4画像照射部と、
前記第1光および前記第2光が入射される第3光入射部と、前記第1光の一部および前記第2光の一部をそれぞれ第1導波光および第2導波光として導波する光導波部と、前記第1導波光および前記第2導波光を出射する第3光出射部を有する導光板部と、
前記第3光入射部に設けられた第1回折格子部を備え、
前記第1回折格子部に対する前記第1光と前記第2光の入射角度が異なっており、
前記第1回折格子部で回折された前記第1光の一部および前記第2光の一部が前記光導波部の全反射条件を満たす画像投影装置。 - 請求項16に記載の画像投影装置であって、
前記第1導波光および前記第2導波光は、前記第3光入射部における入射位置、前記光導波部における反射位置および前記第3光出射部における出射位置がそれぞれ略同一である画像投影装置。 - 請求項16または17に記載の画像投影装置であって、
前記導光板部は、前記第1回折格子部で分岐された光の一つを透過して外部スクリーン方向に出射する第4光出射部を備え、
前記第3光出射部は、前記外部スクリーン方向に対して前記第1導波光および前記第2導波光を出射する画像投影装置。 - 請求項16または17に記載の画像投影装置であって、
画像情報に基づいて制御される微小なミラーを複数有するデジタルミラーデバイスを備え、
前記第3光出射部から出射された前記第1導波光および前記第2導波光は、前記デジタルミラーデバイスを介して視点方向に反射される画像投影装置。 - 請求項16または17に記載の画像投影装置であって、
前記第3光出射部に設けられた第2回折格子部を備え、
前記第2回折格子部は、前記第1導波光の一部および前記第2導波光の一部をそれぞれ回折して第1出射回折光および第2出射回折光として異なる出射角度で視点方向に照射する画像投影装置。 - 請求項20に記載の画像投影装置であって、
前記第1回折格子部と前記第2回折格子部は互いに平行または直交して配置されている画像投影装置。 - 請求項16から21の何れか一項に記載の画像投影装置であって、
二つの前記導光板部を備え、
前記導光板部のそれぞれの前記第3光入射部に、一つの前記第1回折格子部が共通に設けられている画像投影装置。 - 請求項16から22の何れか一項に記載の画像投影装置であって、
前記第1回折格子部は、光入射面を構成する平板状部分と、前記平板状部分と一体に構成された凹凸部分を備え、前記導光板部とは別体に形成されている画像投影装置。 - 請求項16から23の何れか一項に記載の画像投影装置であって、
前記第1回折格子部は、波長変換素子を構成する画像投影装置。
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202280017149.3A CN116917793A (zh) | 2021-02-25 | 2022-02-09 | 图像投影装置 |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2021-028221 | 2021-02-25 | ||
JP2021028219A JP2022129523A (ja) | 2021-02-25 | 2021-02-25 | 画像投影装置 |
JP2021-028219 | 2021-02-25 | ||
JP2021028221A JP2022129525A (ja) | 2021-02-25 | 2021-02-25 | 画像投影装置 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2022181346A1 true WO2022181346A1 (ja) | 2022-09-01 |
Family
ID=83049228
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2022/005196 WO2022181346A1 (ja) | 2021-02-25 | 2022-02-09 | 画像投影装置 |
Country Status (1)
Country | Link |
---|---|
WO (1) | WO2022181346A1 (ja) |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010033026A (ja) * | 2008-06-30 | 2010-02-12 | Hoya Corp | 光伝搬光学素子、映像表示装置、およびヘッドマウントディスプレイ |
JP2014063173A (ja) * | 2004-03-29 | 2014-04-10 | Sony Corp | 画像表示装置 |
JP2018028703A (ja) * | 2013-11-27 | 2018-02-22 | マジック リープ, インコーポレイテッドMagic Leap,Inc. | 仮想現実および拡張現実のシステムおよび方法 |
US20190056593A1 (en) * | 2017-08-18 | 2019-02-21 | Tipd, Llc | Waveguide Image Combiner for Augmented Reality Displays |
WO2020246516A1 (ja) * | 2019-06-05 | 2020-12-10 | 株式会社小糸製作所 | 画像表示装置 |
-
2022
- 2022-02-09 WO PCT/JP2022/005196 patent/WO2022181346A1/ja active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2014063173A (ja) * | 2004-03-29 | 2014-04-10 | Sony Corp | 画像表示装置 |
JP2010033026A (ja) * | 2008-06-30 | 2010-02-12 | Hoya Corp | 光伝搬光学素子、映像表示装置、およびヘッドマウントディスプレイ |
JP2018028703A (ja) * | 2013-11-27 | 2018-02-22 | マジック リープ, インコーポレイテッドMagic Leap,Inc. | 仮想現実および拡張現実のシステムおよび方法 |
US20190056593A1 (en) * | 2017-08-18 | 2019-02-21 | Tipd, Llc | Waveguide Image Combiner for Augmented Reality Displays |
WO2020246516A1 (ja) * | 2019-06-05 | 2020-12-10 | 株式会社小糸製作所 | 画像表示装置 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6867999B2 (ja) | 反射型転換アレイを有する結像光ガイド | |
CA3124368C (en) | Methods and systems for generating virtual content display with a virtual or augmented reality apparatus | |
JP5060704B2 (ja) | 平面型投影ディスプレイ | |
CN110082926B (zh) | 显示装置 | |
CN110221430B (zh) | Hud系统和多屏拼接式衍射显示系统 | |
JP6720315B2 (ja) | 反射型転換アレイを有する結像光ガイド | |
WO2016002138A1 (ja) | 画像表示装置 | |
KR20030088217A (ko) | 배율 조정이 가능한 착용형 디스플레이 시스템 | |
CN110221428B (zh) | 近眼显示系统 | |
CN113167946B (zh) | 集成有扫描镜的投影仪 | |
JP6707934B2 (ja) | 光学素子および表示装置 | |
JP2019191313A (ja) | ヘッドアップディスプレイ装置 | |
JP2023502879A (ja) | 中心窩投影を備えるライトフィールド仮想及び複合現実システム | |
JP2023526018A (ja) | 回折接眼レンズ導波管ディスプレイにおける瞳分離のための方法およびシステム | |
EP4016166A2 (en) | Augmented reality device for providing 3d augmented reality and operating method of the same | |
JP7183981B2 (ja) | 虚像表示装置 | |
JP2022129525A (ja) | 画像投影装置 | |
CN114127611A (zh) | 虚像显示装置 | |
WO2022181346A1 (ja) | 画像投影装置 | |
CN112601587A (zh) | 成像系统中的动态入耦合光栅 | |
US20210382309A1 (en) | Image display device | |
US20240134190A1 (en) | Image projection apparatus | |
JP2022129523A (ja) | 画像投影装置 | |
JP2022530250A (ja) | ホログラフィック導光板 | |
WO2017077965A1 (ja) | 映像表示装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 22759385 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 18278945 Country of ref document: US Ref document number: 202280017149.3 Country of ref document: CN |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 22759385 Country of ref document: EP Kind code of ref document: A1 |