WO2022190751A1 - Aerial display apparatus - Google Patents

Aerial display apparatus Download PDF

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Publication number
WO2022190751A1
WO2022190751A1 PCT/JP2022/005108 JP2022005108W WO2022190751A1 WO 2022190751 A1 WO2022190751 A1 WO 2022190751A1 JP 2022005108 W JP2022005108 W JP 2022005108W WO 2022190751 A1 WO2022190751 A1 WO 2022190751A1
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WO
WIPO (PCT)
Prior art keywords
light
guide plate
display device
light guide
aerial display
Prior art date
Application number
PCT/JP2022/005108
Other languages
French (fr)
Japanese (ja)
Inventor
勝平 浜田
敦 山田
知子 大原
Original Assignee
ミネベアミツミ株式会社
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Application filed by ミネベアミツミ株式会社 filed Critical ミネベアミツミ株式会社
Publication of WO2022190751A1 publication Critical patent/WO2022190751A1/en

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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B30/00—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images
    • G02B30/50—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images the image being built up from image elements distributed over a 3D volume, e.g. voxels
    • G02B30/56—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images the image being built up from image elements distributed over a 3D volume, e.g. voxels by projecting aerial or floating images
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B30/00—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images
    • G02B30/60—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images involving reflecting prisms and mirrors only
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
    • G09F13/00—Illuminated signs; Luminous advertising
    • G09F13/18—Edge-illuminated signs
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N13/00—Stereoscopic video systems; Multi-view video systems; Details thereof
    • H04N13/10—Processing, recording or transmission of stereoscopic or multi-view image signals
    • H04N13/106—Processing image signals
    • H04N13/122—Improving the 3D impression of stereoscopic images by modifying image signal contents, e.g. by filtering or adding monoscopic depth cues
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N13/00—Stereoscopic video systems; Multi-view video systems; Details thereof
    • H04N13/30—Image reproducers
    • H04N13/302—Image reproducers for viewing without the aid of special glasses, i.e. using autostereoscopic displays

Definitions

  • the present invention relates to an aerial display device.
  • an aerial display device includes a retroreflective sheet, a plurality of planar light emitters, and a half mirror.
  • the retroreflective sheet has a plurality of through holes representing figures to be displayed in the air.
  • the plurality of planar light emitters are arranged on the back side of the retroreflective sheet for each light emission pattern formed by the through holes of the retroreflective sheet.
  • the half mirror is arranged on the exit surface side of the retroreflective sheet.
  • An aerial display device is suitable for displaying a fixed light emission pattern in the air, and can change brightness and color for each light emission pattern.
  • FIG. 1 is a diagram of an example of an aerial display device according to an embodiment, viewed from the display surface side.
  • FIG. 2 is a cross-sectional view taken along the line XX in FIG.
  • FIG. 3 is an exploded perspective view of the main parts of the aerial display device.
  • FIG. 4 is a diagram showing an arrangement example of an operation panel in a private toilet room.
  • FIG. 5A is a diagram showing an example of vertical and horizontal light distribution for an aerial display.
  • FIG. 5B is a diagram showing an example of light distribution in the vertical direction and the horizontal direction of a planar light emitter composed of a light guide plate or the like.
  • FIG. 6 is a diagram showing a configuration example of a light source and a light guide plate that constitute a planar light emitter.
  • FIG. 1 is a diagram of an example of an aerial display device according to an embodiment, viewed from the display surface side.
  • FIG. 2 is a cross-sectional view taken along the line XX in FIG.
  • FIG. 7 is a diagram showing another configuration example of the light source and the light guide plate that constitute the planar light emitter.
  • FIG. 8 is a diagram showing an example of changes in emitted light flux with respect to the thickness of the end of the light guide plate for Type-1 and Type-2 in FIG.
  • FIG. 9 is a diagram showing an example of luminance with respect to a light distribution angle in a light guiding direction in a single light guide plate constituting a planar light emitter.
  • FIG. 10 is a diagram showing a configuration example of a light source, a light guide plate, and a prism sheet that constitute a planar light emitter.
  • FIG. 11 is a diagram showing an example of refraction and total reflection of light by the Type-3 prism sheet of FIG. FIG.
  • FIG. 12 is a diagram showing a more specific optimized example of the V-prism optical element provided on the exit surface side of the light guide plate.
  • FIG. 13 is a diagram showing a more specific optimized example of the dot optical elements provided on the reflective emission surface side of the light guide plate and the prism optical elements provided on the reflective emission surface side of the prism sheet.
  • FIG. 14 is a diagram showing an example of light distribution of a planar light emitter composed of an optimized light guide plate or the like.
  • FIG. 15 is a diagram showing an example of luminance with respect to the light distribution angle in the light guiding direction of a planar light emitter composed of an optimized light guide plate or the like.
  • FIG. 16 is a diagram showing an example of an aerial display device serving as a comparative example, viewed from the display surface side. 17 is a cross-sectional view taken along the line XX in FIG. 16.
  • FIG. 16 is a diagram showing an example of an aerial display device serving as a comparative example, viewed from the display surface side.
  • FIG. 1 is a diagram showing an example of an aerial display device 1 according to one embodiment, viewed from the display surface side.
  • FIG. 2 is a cross-sectional view taken along the line XX in FIG.
  • FIG. 3 is an exploded perspective view of the main part of the aerial display device 1.
  • FIG. The aerial display device 1 shown in FIGS. 1 to 3 is assumed to be used as an operation panel installed on the wall surface of a private restroom or the like, and the display surface faces the horizontal direction.
  • the aerial display device 1 has a reflective sheet 8 fixed to a portion of the inner bottom surface 2b of the frame 2 in which a substantially rectangular opening 2a is formed.
  • a planar light emitter composed of a substrate 31, a light source 32, a light guide plate 4, a prism sheet 15, and a louver sheet 10 is provided for each light emission pattern.
  • Each light guide plate 4 is arranged to face the reflecting surface of the reflecting sheet 8 .
  • a common light source control board 16 is provided for a plurality of planar light emitters, and one end of the board 31 is connected to the light source control board 16 .
  • the light source control board 16 is fixed to the non-emission surface side of the sensor electrode 14A, which will be described later.
  • each light guide plate 4 on the light incident side surface 4 a side is fixed to the substrate 31 , and the light incident side surface 4 a faces the light emitting portion of the light source 32 arranged on the substrate 31 .
  • a predetermined range on the side of the light incident side surface 4a of the light guide plate 4 is a color mixing area for color mixing, and the main surface on the terminal side thereof is an exit surface.
  • Sheets 10 are arranged one on top of the other. Note that the louver sheet 10 may be omitted.
  • a retroreflective sheet 5 having a plurality of through holes 5a representing figures to be displayed in the air is provided.
  • the reflecting surface is directed toward the exit surface side (the side opposite to the light guide plate 4).
  • the reflective sheet 8 is for increasing light efficiency and brightness by returning light leaking from the light guide plate 4 to the back side to the light guide plate 4 .
  • the substrate 31 is configured by a flexible substrate or the like, and includes wiring for supplying power to the light source 32 .
  • the light source 32 is, for example, a side-view type (a type that emits light from the side surface of the package) RGB-LED having red, green, and blue light emitting elements inside. are provided. By using RGB-LEDs, it becomes easier to control the emission color. In addition, since the RGB-LED is small, it is possible to reduce the thickness of the planar light emitter. By making the RGB-LED a side-view type, the substrate can be arranged parallel to the emission surface, and further reduction in thickness can be achieved.
  • the light source 32 can be a top-view type (a type that emits light from the top surface of the package) RGB-LED, although the advantage of thinning is lost.
  • the light source control board 16 is mounted with control circuit components for controlling the amount and color of light emitted from the light source 32 .
  • the light guide plate 4 is made of a transparent material such as polycarbonate or acryl, guides the light incident from the light incident side surface 4a to the end side, and diffuses the light by dot optical elements provided on the back surface (non-display surface) side.
  • the V-prism optical element (a lenticular lens is also possible) provided on the exit surface side controls the light distribution in the arrangement pitch direction of the light sources 32 .
  • a prism sheet 15 is provided to control the light distribution in the light guiding direction.
  • the prism sheet 15 is a sheet in which prisms extending in one direction (the X-axis direction in the drawing) are formed on the surface of a transparent sheet. These are realized by the light guide plate 4 and the prism sheet 15 by not using the linear light source in the comparative examples (FIGS. 16 and 17) to be described later, and controlling the light distribution that the linear light source was responsible for. .
  • the louver sheet 10 is a sheet that functions to pass light in a predetermined direction (light directed downward to the left in FIG. 2) and suppress light in other directions. Details of functions of the dot optical element of the light guide plate 4, the V-prism optical element, and the prism sheet 15 will be described later.
  • the portion of the retroreflective sheet 5 on the exit surface side where the through holes 5a are not provided has the property of emitting the incident light through the same path (the incident angle and the emitting angle are the same).
  • the retroreflective sheet 5 has, for example, transparent microscopic glass bead spheres or the like arranged on the surface without gaps.
  • the retroreflective sheet 5 utilizes the inner surfaces of the vertexes of a cube called a corner cube, in which three surfaces having the property of reflecting light are combined at right angles to each other. can also be used. In this case, although the cost is slightly higher, there is an advantage that the light utilization efficiency is high and the blurring of the aerial display (aerial image) is reduced.
  • a half mirror 6 is arranged on the display surface side of the frame 2 so as to cover the opening 2a, and a top cover 7 is superimposed on the half mirror 6 on the outside.
  • the top cover 7 can be omitted by applying a hard coat treatment to the outer side (viewing side) of the half mirror 6, but since the half mirror 6 is in the form of a film, a transparent resin plate for support is required. Become.
  • the hard coat treatment is performed for the purpose of scratch prevention, antifouling, antibacterial, etc. Even when the top cover 7 is arranged on the outside, it is preferable to apply the hard coat treatment to the top cover 7 .
  • the half mirror 6 is an optical member that has the property of reflecting about half of the incident light and transmitting about the remaining half.
  • the top cover 7 is made of transparent material and serves to protect the half mirror 6 . By reducing the transmittance of the top cover 7, it becomes difficult to see the inside of the aerial display device 1 from the outside, and only the aerial display can be seen easily. Also, the retroreflective sheet 5 and the half mirror 6 may be arranged with a slight inclination to each other.
  • a pair of sensor electrodes 14A and 14B are provided vertically (in the Y-axis direction) for each light emission pattern.
  • a voltage between the sensor electrodes 14A and 14B electric lines of force are generated between the sensor electrodes 14A and 14B.
  • a touch on the aerial display I can be detected from the change. Since the user's finger F only touches the aerial display I and does not touch an actual button or the like, it is desirable from a sanitary point of view.
  • an IR (infrared) sensor or the like may be used to detect the contact of the finger F with the aerial display I and control the on/off of the corresponding function.
  • light emitted from the light source 32 through the light guide plate 4, the prism sheet 15 and the louver sheet 10 passes through the through holes 5a of the retroreflective sheet 5 and exits along the path L1.
  • the dot optical element of the light guide plate 4, the V prism optical element, and the prism sheet 15, the light is emitted in a direction where the eye point EP on the display surface side does not exist (lower left side in FIG. 2), and the eye point EP is The existing light emitted in a predetermined direction (light emitted through the path L0) is suppressed.
  • the eyepoint EP is a position that is assumed to be viewed by the user.
  • FIG. 4 is a diagram showing an arrangement example of the operation panel 100 in the private toilet room.
  • An aerial display device 1 is arranged in front of the operation panel 100 .
  • the operation panel 100 is provided at a position on the wall W within easy reach of the user M sitting on the toilet seat T.
  • the height of the operation panel 100 from the floor surface is, for example, 1 m, and the horizontal position is equivalent to the position of the user M's knees.
  • the vertical viewing range of the aerial display I is, for example, 10 degrees to 35 degrees above the horizontal direction.
  • the horizontal viewing range of the aerial display I is, for example, ⁇ 40 degrees.
  • FIG. 5A is a diagram showing an example of vertical and horizontal light distribution of the aerial display device 1, where the vertical axis is the vertical light distribution angle (0° at the front) and the horizontal axis is the horizontal light distribution angle. (0° to the front).
  • the light distribution is defined more strictly in consideration of the ratio of the luminance of each point to the central luminance.
  • the central luminance is the luminance at the point where the vertical direction is 23° and the horizontal direction is 0°
  • the points where the ratio of luminance to the central luminance should be 50% or more are indicated by black circles, and the ratio is 30% or more.
  • the black squares indicate the points where .
  • FIG. 5B is a diagram showing an example of light distribution in the vertical and horizontal directions of a planar light emitter composed of the light guide plate 4 and the like.
  • the horizontal direction is the same as in FIG. It's reversed. This is because, as described above, due to the reflection by the half mirror 6 and the retroreflection by the retroreflection sheet 5, the emission direction from the planar light emitter has a symmetrical relationship with the direction in which the aerial display is performed.
  • FIG. 6 is a diagram showing a configuration example of the light source 32 and the light guide plate 4 that constitute the planar light emitter.
  • the left side is a view seen from the front of the display surface
  • the right side is a view seen from the side.
  • the light entrance side of the light guide plate 4 (the side where the light entrance side surface 4a is provided) is provided with a color mixing area of 10 mm with respect to the overall length of 37 mm for color mixing of the light source 32 by the RGB-LEDs.
  • the dot optical element 4d for emission is not provided in this mixed color area, and the dot optical element 4d is provided in the effective area below the mixed color area. This is because the red, green, and blue light-emitting elements are arranged at small intervals in the RGB-LED package. This is because parting will occur.
  • an optical element such as a lenticular lens or a prism for diffusing light on the light incident side surface 4a of the light guide plate 4
  • color mixing can be completed in a short distance, and the length of the light guide direction of the color mixing area can be shortened. can be done.
  • a V-prism optical element (a lenticular lens is also possible) for controlling the light distribution in the pitch direction of the light source 32 is provided on the light emitting surface side of the light guide plate 4, which will be described later.
  • FIG. 7 is a diagram showing another configuration example of the light source 32 and the light guide plate 4 that constitute the planar light emitter.
  • two types having a wedge-shaped cross section with different thicknesses of the light guide plate 4 are shown in the right side view.
  • Type-1 the thickness is reduced in the mixed color area from the incident side surface 4a having a thickness (1 mm) to match the size of the light source 32, and the thickness is constant in the effective area.
  • Type-2 has a thickness (1 mm) to match the size of the light source 32, and the thickness is reduced from the incident side surface 4a to the terminal end side.
  • the back side on which the dot optical element 4d is provided is an inclined surface.
  • FIG. 8 is a diagram showing an example of changes in emitted light flux with respect to the thickness of the terminal end of the light guide plate 4 according to Type-1 and Type-2 in FIG.
  • Type-2 is preferable in the area where the thickness of the terminal end of the light guide plate 4 is thin, because the emitted light flux is larger. This is because, in Type-1, the angle of light reflection changes in the portion from the light incident side surface 4a until the thickness decreases and becomes constant, and light whose light distribution cannot be controlled is generated.
  • FIG. 9 is a diagram showing an example of the luminance with respect to the light distribution angle in the light guide direction of the light guide plate 4 alone constituting the planar light emitter, and is based on the Type-2 light guide plate 4 in FIG.
  • the four curves correspond to the contact angle of the dot optical element 4d provided on the back surface of the light guide plate 4 (the angle formed by the tangent to the edge of the spherical surface forming the dots and the plane on which the dots are provided). ing.
  • the solid line is for a contact angle of 10°
  • the dashed line is for a contact angle of 20°
  • the one-dot-two chain line is for a contact angle of 30°
  • the two-dot chain line is for a contact angle of 40°.
  • the rectangular broken line area shown near the center of FIG. 9 corresponds to the vertical light distribution range (FIG. 5B) required for the planar light emitter, and the dot optical element 4d alone is sufficient. It can be seen that the light distribution in the vertical direction cannot be controlled. Therefore, the prism sheet 15 is provided.
  • FIG. 10 is a diagram showing a configuration example of the light source 32, the light guide plate 4, and the prism sheet 15 that constitute the planar light emitter.
  • a V-prism optical element 4e is provided for controlling the light distribution in the pitch direction of the arrangement of the light sources 32 when viewed from the front of the display surface on the left side.
  • the V-prism optical element 4e has a triangular concavo-convex surface as shown in a partially enlarged view.
  • the V-prism optical element 4e can be replaced by a lenticular lens having an arc-shaped cross section.
  • FIG. 10 is a diagram showing an example of refraction and total reflection of light by the Type-3 prism sheet 15 of FIG.
  • incident light L11 is refracted to become light L12, and further refracted to emerge as light L13.
  • the light L21 enters the inside, becomes light L22 by total reflection, is further refracted, and is emitted as light L23.
  • Type-4 has a wider light distribution than Type-3, and more light is emitted in the direction of the eye point, which is not preferable. Therefore, Type-3 is more preferable.
  • FIG. 12 is a diagram showing a more specific optimized example of the V-prism optical element 4e provided on the exit surface side of the light guide plate 4.
  • the length of the base of the triangular cross section of the V-prism optical element 4e is 100 ⁇ m
  • the base angle of both ends is 10°
  • the apex angle is 160°.
  • FIG. 13 is a diagram showing a more specific optimized example of the dot optical element 4d provided on the reflective emission surface side of the light guide plate 4 and the prism optical element 15a provided on the reflective emission surface side of the prism sheet 15.
  • the dot optical element 4d of the light guide plate 4 has a contact angle of 29.6°, a bottom diameter of 40 ⁇ m, and a height of 5.2 ⁇ m.
  • the base angle of the upper side of the prism optical element 15a of the prism sheet 15 is 74.4°, the apex angle is 75°, and the pitch is 50 ⁇ m.
  • FIG. 14 is a diagram showing an example of the light distribution of a planar light emitter composed of the optimized light guide plate 4 and the like. It is a horizontal light distribution angle (0° at the front). A rectangular area surrounded by a dashed line in the figure corresponds to the area where the ratio is 30% in FIG. 5B.
  • the luminance at each light distribution angle ([cd/m 2 ]) and the ratio of luminance to the central luminance ([%]) are shown in Table 1 below. It is assumed that the louver sheet 10 is not provided. As can be seen from Table 1, the requirements for the light distribution of Figure 5B are met.
  • FIG. 15 is a diagram showing an example of luminance with respect to the light distribution angle in the light guiding direction of a planar light emitter composed of the optimized light guide plate 4 and the like. It is assumed that the louver sheet 10 is not provided.
  • the solid-line curve indicates the case of the above-mentioned optimized Type-3, and the broken-line curve indicates the case of Type-4 with the prism surface on the output side for comparison.
  • a rectangular area surrounded by a dashed line near -30° in the figure corresponds to the area (target area) where the ratio is 30% in FIG. 5B.
  • a rectangular area surrounded by dashed lines of 0° or more is light that is directly emitted in the direction of the eyepoint, and is light that should be suppressed as small as possible.
  • the brightness of Type-4 is higher in the target area, but the amount of light directly emitted in the direction of the eye point is also increased, which is not preferable.
  • the light emitted directly in the direction of the eyepoint is sufficiently suppressed.
  • the louver sheet 10 is used when that portion needs to be removed. The louver sheet 10 passes light in the direction of the target area and suppresses light in other directions.
  • FIG. 16 is a view from the display surface side showing an example of an aerial display device 1' serving as a comparative example.
  • 17 is a cross-sectional view taken along the line XX in FIG. 16.
  • an aerial display device 1' has a linear light source 3' and a light guide plate 4' which constitute a planar light emitter in a frame 2' having a substantially rectangular opening 2a'. are placed.
  • the linear light source 3' is a light source that emits linear light along the longitudinal direction (X-axis direction) of the light incident side surface 4a' of the light guide plate 4'. It includes a light bar and a prism bar molded out of transparent material.
  • the light guide plate 4' is similarly formed of a transparent material such as polycarbonate or acrylic, guides the light incident from the light incident side surface 4a' to the end side, and is provided on the rear surface (non-display surface) side. Light is reflected by the light-emitting portion 4b' formed by. By adjusting the optical element of the light emitting unit 4b', the light is emitted in a direction where the eye point EP' on the display surface side does not exist (lower left side in FIG. 17), and is emitted in a predetermined direction where the eye point EP' exists. I try to keep the light out.
  • the light-emitting portion 4b' of the light guide plate 4' covers the positions of a plurality of through-holes 5a' that may be used to represent a figure to be displayed in the air in the retroreflective sheet 5' described later.
  • a reflective sheet 8' is arranged so as to cover the opening 2a'. , which increases light efficiency and brightness.
  • a retroreflective sheet 5′ having a plurality of through-holes 5a′ representing figures to be displayed in the air at positions corresponding to the light emitting parts 4b′ is provided so that the reflection surface is on the exit surface side. It is arranged toward (the side opposite to the light guide plate 4').
  • a half mirror 6' is arranged on the display surface side of the frame 2' so as to cover the opening 2a', and a top cover 7' is superimposed on the outside of the half mirror 6'.
  • the light emitted from the light emitting portion 4b' of the light guide plate 4' which constitutes the planar light emitter, passes through the through hole 5a' of the retroreflective sheet 5' and emerges along the path L1'. About half of this light is reflected by the half mirror 6' and strikes the retroreflective sheet 5' along the path L2'. The light striking the retroreflective sheet 5' returns to the half mirror 6' along the path L3' at the same exit angle as the incident angle, and about half of the light is transmitted. Even if the angle of the path L1' changes, the light emitted from a certain point of the light emitting part 4b' passes through the same position outside the aerial display device 1' due to the geometric relationship.
  • An aerial display I' by an aerial image is performed on the outside of ', can be visually recognized from the user's eye point EP', and can cause the user to perform a touching action with the finger F'.
  • the floating display device 1' of the comparative example shown in FIGS. 16 and 17 light is supplied from the light emitting portion 4b' of one light guide plate 4' for all the light emission patterns of the through holes 5a' of the retroreflective sheet 5'. Therefore, it was difficult to change the brightness and color for each light emission pattern.
  • the aerial display device 1 of the embodiments of FIGS. 1 to 15 since the planar light emitter is provided for each light emission pattern, it becomes easy to change the brightness and color for each light emission pattern.
  • the planar light emitter is composed of a linear light source 3' and a light guide plate 4', and the linear light source 3' is composed of a light bar and a prism bar. Since there are many types of molded products and many types of molds, it is difficult to reduce costs. In this respect, according to the aerial display device 1 of the embodiment of FIGS. 1 to 15, the molded product is only the light guide plate 4, so even if there are a plurality of light guide plates 4, it can be manufactured from one mold. , cost reduction can be achieved by reducing the number of types of molds. Further, according to the aerial display device 1 of the embodiment, since the RGB-LED is used for the light source 32, it is possible to easily control the color of the aerial display and to achieve a thin device.
  • the aerial display device includes a retroreflective sheet having a plurality of through-holes representing figures to be displayed in mid-air, and light emitting patterns formed by the through-holes of the retroreflective sheet. and a half-mirror arranged on the exit surface side of the retroreflective sheet. This makes it suitable for displaying a fixed light emission pattern in the air, and allows the brightness and color to be changed for each light emission pattern.
  • the planar light emitter includes a plurality of point-like light sources, a light guide plate having a light incident side surface facing the plurality of point-like light sources and having dot optical elements provided on one main surface, and a light guide plate. and a prism sheet that is arranged on the exit surface side and controls the light distribution in the light guide direction.
  • the light guide plate which can be manufactured with one type of mold, is enough for the molded product, so that the cost can be reduced.
  • even without using a linear light source it is possible to achieve uniformity in brightness and control the light distribution to a desired level.
  • the light guide plate is provided with an optical element consisting of a V-prism or a lenticular lens for controlling the light distribution in the pitch direction of the plurality of point-like light sources on the other principal surface.
  • an optical element consisting of a V-prism or a lenticular lens for controlling the light distribution in the pitch direction of the plurality of point-like light sources on the other principal surface.
  • the plurality of point-like light sources are RGB-LEDs each having red, green, and blue light-emitting elements inside. As a result, it is possible to easily control the color of the aerial display and to reduce the thickness of the device.
  • the light guide plate has, on the light incident side, a color mixing area in which dot optical elements are not provided for color mixing. Thereby, sufficient color mixing is performed, and color separation can be prevented.
  • another optical element for diffusing light is provided on the light incident side surface of the light guide plate.
  • the length of the color mixing area for color mixing in the light guiding direction can be shortened.
  • the light guide plate has a wedge-shaped cross section in which the thickness on the terminal side is thinner than the thickness on the light incident side.
  • the prism surface of the prism sheet is provided on the light guide plate side surface or the exit surface side surface.
  • the prism surface is provided on the light guide plate side, the light distribution can be narrowed compared to when the prism surface is provided on the exit surface side, and the emitted light in the direction of the eye point can be reduced. can.
  • the prism surface is provided on the surface on the output surface side, the performance is slightly degraded, but it can be sufficiently put into practical use.
  • planar light emitter includes a louver sheet arranged on the exit surface side. As a result, the emitted light in the eyepoint direction can be further reduced.
  • the present invention is not limited by the above-described embodiment.
  • the present invention also includes those configured by appropriately combining the respective constituent elements described above. Further effects and modifications can be easily derived by those skilled in the art. Therefore, broader aspects of the present invention are not limited to the above-described embodiments, and various modifications are possible.
  • 1 aerial display device 2 frame, 2a aperture, 2b bottom surface, 31 substrate, 32 light source, 4 light guide plate, 4a light incident side surface, 4d dot optical element, 4e V prism optical element, 5 retroreflective sheet, 5a through hole, 6 Half mirror, 7 Top cover, 8 Reflection sheet, 10 Louver sheet, 14A, 14B Sensor electrode, 15 Prism sheet, 15a Prism optical element, 16 Light source control board, EP Eye point, I Air display, F Finger

Abstract

An aerial display apparatus (1) according to an embodiment comprises a retroreflection sheet (5), a plurality of planar light-emitting bodies (32, 4), and a half mirror (6). The retroreflection sheet (5) has a plurality of through-holes (5a) representing a figure to be aerially displayed. The plurality of planar light-emitting bodies (32, 4) are disposed on the back surface side of the retroreflection sheet with respect to each light emission pattern formed by the through-holes (5a) of the retroreflection sheet (5). The half mirror (6) is disposed on the emission surface side of the retroreflection sheet (5).

Description

空中表示装置aerial display
　本発明は、空中表示装置に関する。 The present invention relates to an aerial display device.
　従来から、再帰反射シートやハーフミラーが用いられ、空中に画像を結像させる空中表示装置が提案されている（例えば、特許文献１、２等を参照）。 Conventionally, an aerial display device that forms an image in the air using a retroreflective sheet or a half mirror has been proposed (see, for example, Patent Documents 1 and 2).
特開２０１８－８１１３８号公報Japanese Patent Application Laid-Open No. 2018-81138 特開２０１７－１０７１６５号公報JP 2017-107165 A
　しかしながら、従来の技術では、画像出力装置やディスプレイを光源として使用しており、固定的な発光パターンを空中表示するのには適していなかった。また、固定的な発光パターンを空中表示する場合、単一の固定的な光源が用いられることが多く、発光パターンごとに明るさや色を変えることは困難となる。 However, conventional technology uses an image output device or display as a light source, and is not suitable for displaying a fixed light emission pattern in the air. Moreover, when a fixed light emission pattern is displayed in the air, a single fixed light source is often used, and it is difficult to change the brightness and color for each light emission pattern.
　本発明は、上記に鑑みてなされたものであって、固定的な発光パターンを空中表示するのに適し、発光パターンごとに明るさや色を変えることのできる空中表示装置を提供することを目的とする。 SUMMARY OF THE INVENTION It is an object of the present invention to provide an aerial display device suitable for displaying a fixed light emission pattern in the air and capable of changing the brightness and color for each light emission pattern. do.
　上述した課題を解決し、目的を達成するために、本発明の一態様に係る空中表示装置は、再帰反射シートと、複数の面状発光体と、ハーフミラーとを備える。前記再帰反射シートは、空中表示する図形を表した複数の貫通孔を有する。前記複数の面状発光体は、前記再帰反射シートの前記貫通孔による発光パターンごとに、前記再帰反射シートの裏面側に配置される。前記ハーフミラーは、前記再帰反射シートの出射面側に配置される。 In order to solve the above problems and achieve the object, an aerial display device according to one aspect of the present invention includes a retroreflective sheet, a plurality of planar light emitters, and a half mirror. The retroreflective sheet has a plurality of through holes representing figures to be displayed in the air. The plurality of planar light emitters are arranged on the back side of the retroreflective sheet for each light emission pattern formed by the through holes of the retroreflective sheet. The half mirror is arranged on the exit surface side of the retroreflective sheet.
　本発明の一態様に係る空中表示装置は、固定的な発光パターンを空中表示するのに適し、発光パターンごとに明るさや色を変えることができる。 An aerial display device according to one aspect of the present invention is suitable for displaying a fixed light emission pattern in the air, and can change brightness and color for each light emission pattern.
図１は、一実施形態にかかる空中表示装置の例を示す表示面側から見た図である。FIG. 1 is a diagram of an example of an aerial display device according to an embodiment, viewed from the display surface side. 図２は、図１におけるＸ－Ｘ断面図である。FIG. 2 is a cross-sectional view taken along the line XX in FIG. 図３は、空中表示装置の主要部の分解斜視図である。FIG. 3 is an exploded perspective view of the main parts of the aerial display device. 図４は、トイレ個室内における操作パネルの配置例を示す図である。FIG. 4 is a diagram showing an arrangement example of an operation panel in a private toilet room. 図５Ａは、空中表示装置の垂直方向および水平方向の配光の例を示す図である。FIG. 5A is a diagram showing an example of vertical and horizontal light distribution for an aerial display. 図５Ｂは、導光板等から構成される面状発光体の垂直方向および水平方向の配光の例を示す図である。FIG. 5B is a diagram showing an example of light distribution in the vertical direction and the horizontal direction of a planar light emitter composed of a light guide plate or the like. 図６は、面状発光体を構成する光源と導光板の構成例を示す図である。FIG. 6 is a diagram showing a configuration example of a light source and a light guide plate that constitute a planar light emitter. 図７は、面状発光体を構成する光源と導光板の他の構成例を示す図である。FIG. 7 is a diagram showing another configuration example of the light source and the light guide plate that constitute the planar light emitter. 図８は、図７のType-1とType-2とによる、導光板の終端の厚さに対する出射光束の変化の例を示す図である。FIG. 8 is a diagram showing an example of changes in emitted light flux with respect to the thickness of the end of the light guide plate for Type-1 and Type-2 in FIG. 図９は、面状発光体を構成する導光板単体での導光方向の配光角度に対する輝度の例を示す図である。FIG. 9 is a diagram showing an example of luminance with respect to a light distribution angle in a light guiding direction in a single light guide plate constituting a planar light emitter. 図１０は、面状発光体を構成する光源と導光板とプリズムシートの構成例を示す図である。FIG. 10 is a diagram showing a configuration example of a light source, a light guide plate, and a prism sheet that constitute a planar light emitter. 図１１は、図１０のType-3のプリズムシートによる光の屈折と全反射の例を示す図である。FIG. 11 is a diagram showing an example of refraction and total reflection of light by the Type-3 prism sheet of FIG. 図１２は、導光板の出射面側に設けられるＶプリズム光学素子の最適化されたより具体的な例を示す図である。FIG. 12 is a diagram showing a more specific optimized example of the V-prism optical element provided on the exit surface side of the light guide plate. 図１３は、導光板の反出射面側に設けられるドット光学素子とプリズムシートの反出射面側に設けられるプリズム光学素子の最適化されたより具体的な例を示す図である。FIG. 13 is a diagram showing a more specific optimized example of the dot optical elements provided on the reflective emission surface side of the light guide plate and the prism optical elements provided on the reflective emission surface side of the prism sheet. 図１４は、最適化された導光板等から構成される面状発光体の配光の例を示す図である。FIG. 14 is a diagram showing an example of light distribution of a planar light emitter composed of an optimized light guide plate or the like. 図１５は、最適化された導光板等から構成される面状発光体の導光方向の配光角度に対する輝度の例を示す図である。FIG. 15 is a diagram showing an example of luminance with respect to the light distribution angle in the light guiding direction of a planar light emitter composed of an optimized light guide plate or the like. 図１６は、比較例となる空中表示装置の例を示す表示面側から見た図である。FIG. 16 is a diagram showing an example of an aerial display device serving as a comparative example, viewed from the display surface side. 図１７は、図１６におけるＸ－Ｘ断面図である。17 is a cross-sectional view taken along the line XX in FIG. 16. FIG.
　以下、実施形態に係る空中表示装置について図面を参照して説明する。なお、この実施形態によりこの発明が限定されるものではない。また、図面における各要素の寸法の関係、各要素の比率などは、現実と異なる場合がある。図面の相互間においても、互いの寸法の関係や比率が異なる部分が含まれている場合がある。また、１つの実施形態や変形例に記載された内容は、原則として他の実施形態や変形例にも同様に適用される。 An aerial display device according to an embodiment will be described below with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, the dimensional relationship of each element in the drawings, the ratio of each element, and the like may differ from reality. Even between the drawings, there are cases where portions with different dimensional relationships and ratios are included. In principle, the contents described in one embodiment and modification are similarly applied to other embodiments and modifications.
　図１は、一実施形態にかかる空中表示装置１の例を示す表示面側から見た図である。図２は、図１におけるＸ－Ｘ断面図である。図３は、空中表示装置１の主要部の分解斜視図である。なお、図１～図３における空中表示装置１は、個室トイレ内の壁面等に設置される操作パネルに採用されることが想定されており、表示面が水平方向を向いている。 FIG. 1 is a diagram showing an example of an aerial display device 1 according to one embodiment, viewed from the display surface side. FIG. 2 is a cross-sectional view taken along the line XX in FIG. FIG. 3 is an exploded perspective view of the main part of the aerial display device 1. FIG. The aerial display device 1 shown in FIGS. 1 to 3 is assumed to be used as an operation panel installed on the wall surface of a private restroom or the like, and the display surface faces the horizontal direction.
　図１～図３において、空中表示装置１は、略矩形状の開口２ａが形成されたフレーム２の内側の底面２ｂの一部に反射シート８が固定されている。また、基板３１、光源３２、導光板４、プリズムシート１５およびルーバーシート１０から構成される面状発光体が発光パターンごとに設けられており、それぞれの基板３１が反射シート８と並んでフレーム２の底面２ｂに固定されており、それぞれの導光板４は反射シート８の反射面に対向するように配置されている。また、複数の面状発光体に共通の光源制御基板１６が設けられ、基板３１の一端が光源制御基板１６に接続されている。光源制御基板１６は、後述するセンサ電極１４Ａの非出射面側に固定されている。 1 to 3, the aerial display device 1 has a reflective sheet 8 fixed to a portion of the inner bottom surface 2b of the frame 2 in which a substantially rectangular opening 2a is formed. A planar light emitter composed of a substrate 31, a light source 32, a light guide plate 4, a prism sheet 15, and a louver sheet 10 is provided for each light emission pattern. Each light guide plate 4 is arranged to face the reflecting surface of the reflecting sheet 8 . A common light source control board 16 is provided for a plurality of planar light emitters, and one end of the board 31 is connected to the light source control board 16 . The light source control board 16 is fixed to the non-emission surface side of the sensor electrode 14A, which will be described later.
　それぞれの導光板４の裏側の主面の入光側面４ａ側の端部は基板３１に固定され、入光側面４ａは基板３１上に配置された光源３２の発光部に対向するようになっている。導光板４の入光側面４ａ側の所定の範囲は混色のための混色エリアとなっており、それよりも終端側の主面が出射面となっており、この出射面にプリズムシート１５およびルーバーシート１０が重ねて配置されている。なお、ルーバーシート１０は省略される場合もある。 The end portion of the main surface on the back side of each light guide plate 4 on the light incident side surface 4 a side is fixed to the substrate 31 , and the light incident side surface 4 a faces the light emitting portion of the light source 32 arranged on the substrate 31 . there is A predetermined range on the side of the light incident side surface 4a of the light guide plate 4 is a color mixing area for color mixing, and the main surface on the terminal side thereof is an exit surface. Sheets 10 are arranged one on top of the other. Note that the louver sheet 10 may be omitted.
　更に、ルーバーシート１０の出射面側（ルーバーシート１０が省略される場合にはプリズムシート１５の出射面側）には、空中表示する図形を表した複数の貫通孔５ａを有する再帰反射シート５が、反射面を出射面側（導光板４とは反対側）に向けて配置されている。 Further, on the exit surface side of the louver sheet 10 (the exit surface side of the prism sheet 15 when the louver sheet 10 is omitted), a retroreflective sheet 5 having a plurality of through holes 5a representing figures to be displayed in the air is provided. , the reflecting surface is directed toward the exit surface side (the side opposite to the light guide plate 4).
　反射シート８は、導光板４から背面側へ漏れる光を導光板４に戻すことで、光効率を高め、輝度を高めるためのものである。基板３１は、フレキシブル基板等により構成され、光源３２への給電のための配線を含む。光源３２は、例えば、赤・緑・青の発光素子を内部に有するサイドビュー型（パッケージの側面から発光するタイプ）のＲＧＢ－ＬＥＤであり、図示の例では１つの導光板４に対して３個が設けられている。ＲＧＢ－ＬＥＤとすることで、発光色の制御が容易になる。また、ＲＧＢ－ＬＥＤは小型であるため面状発光体の薄型化が図れる。ＲＧＢ－ＬＥＤをサイドビュー型とすることで、基板を出射面に平行に配置することができ、更なる薄型化が図れる。なお、薄型化の利点は薄れるが、基板３１の配置を変更し、光源３２としてトップビュー型（パッケージの天面から発光するタイプ）のＲＧＢ－ＬＥＤとすることもできる。光源制御基板１６には、光源３２の発光量や発光色を制御するための制御回路部品が搭載されている。 The reflective sheet 8 is for increasing light efficiency and brightness by returning light leaking from the light guide plate 4 to the back side to the light guide plate 4 . The substrate 31 is configured by a flexible substrate or the like, and includes wiring for supplying power to the light source 32 . The light source 32 is, for example, a side-view type (a type that emits light from the side surface of the package) RGB-LED having red, green, and blue light emitting elements inside. are provided. By using RGB-LEDs, it becomes easier to control the emission color. In addition, since the RGB-LED is small, it is possible to reduce the thickness of the planar light emitter. By making the RGB-LED a side-view type, the substrate can be arranged parallel to the emission surface, and further reduction in thickness can be achieved. By changing the layout of the substrate 31, the light source 32 can be a top-view type (a type that emits light from the top surface of the package) RGB-LED, although the advantage of thinning is lost. The light source control board 16 is mounted with control circuit components for controlling the amount and color of light emitted from the light source 32 .
　導光板４は、ポリカーボネートやアクリル等の透明材料により形成され、入光側面４ａから入射された光を終端側まで導き、裏面（非表示面）側に設けられたドット光学素子により光の拡散を行って輝度均一性を維持するとともに、出射面側に設けられたＶプリズム光学素子（レンチキュラーレンズも可）により光源３２の配列ピッチ方向の配光を制御するようにしている。また、導光方向の配光を制御するために、プリズムシート１５が設けられている。 The light guide plate 4 is made of a transparent material such as polycarbonate or acryl, guides the light incident from the light incident side surface 4a to the end side, and diffuses the light by dot optical elements provided on the back surface (non-display surface) side. In addition, the V-prism optical element (a lenticular lens is also possible) provided on the exit surface side controls the light distribution in the arrangement pitch direction of the light sources 32 . A prism sheet 15 is provided to control the light distribution in the light guiding direction.
　プリズムシート１５は、透明シートの表面に一方向（図におけるＸ軸方向）に延びるプリズムが形成されたシートである。これらは、後述する比較例（図１６、図１７）における線状光源を用いないことで、線状光源が担っていた配光の制御を導光板４とプリズムシート１５とによって実現したものである。ルーバーシート１０は、所定の方向の光（図２では左下向きの光）を通し、その他の方向の光を抑制するように機能するシートである。導光板４のドット光学素子、Ｖプリズム光学素子およびプリズムシート１５の働きの詳細については後述する。 The prism sheet 15 is a sheet in which prisms extending in one direction (the X-axis direction in the drawing) are formed on the surface of a transparent sheet. These are realized by the light guide plate 4 and the prism sheet 15 by not using the linear light source in the comparative examples (FIGS. 16 and 17) to be described later, and controlling the light distribution that the linear light source was responsible for. . The louver sheet 10 is a sheet that functions to pass light in a predetermined direction (light directed downward to the left in FIG. 2) and suppress light in other directions. Details of functions of the dot optical element of the light guide plate 4, the V-prism optical element, and the prism sheet 15 will be described later.
　再帰反射シート５の出射面側の貫通孔５ａが設けられていない部分は、入射された光を同じ経路で出射（入射角と出射角が同じ）する性質を有している。再帰反射シート５は、例えば、透明の微小なガラスビーズ球などが表面に隙間なく配置されたものである。また、再帰反射シート５としては、ガラスビーズ球の他に、コーナーキューブと呼ばれる、光を反射する性質を持った３枚の面が互いに直角に組み合わされた、立方体の頂点の内面を利用したものも使用することができる。この場合、コストは若干高くなるが、光利用効率が高く、空中表示（空中像）のボケが少なくなるという利点がある。 The portion of the retroreflective sheet 5 on the exit surface side where the through holes 5a are not provided has the property of emitting the incident light through the same path (the incident angle and the emitting angle are the same). The retroreflective sheet 5 has, for example, transparent microscopic glass bead spheres or the like arranged on the surface without gaps. In addition to the glass bead spheres, the retroreflective sheet 5 utilizes the inner surfaces of the vertexes of a cube called a corner cube, in which three surfaces having the property of reflecting light are combined at right angles to each other. can also be used. In this case, although the cost is slightly higher, there is an advantage that the light utilization efficiency is high and the blurring of the aerial display (aerial image) is reduced.
　一方、フレーム２の表示面側には、開口２ａを覆うようにハーフミラー６が配置され、ハーフミラー６にはトップカバー７が外側に重ねられている。なお、ハーフミラー６の外側（視認側）にハードコート処理を施すことにより、トップカバー７を省略することもできるが、ハーフミラー６はフィルム状であるため、支持用の透明樹脂板が必要となる。なお、ハードコート処理は、傷防止や汚れ防止、抗菌などを目的として施されるものであり、トップカバー７が外側に配置される場合でも、トップカバー７にハードコート処理を施すのが好ましい。 On the other hand, a half mirror 6 is arranged on the display surface side of the frame 2 so as to cover the opening 2a, and a top cover 7 is superimposed on the half mirror 6 on the outside. The top cover 7 can be omitted by applying a hard coat treatment to the outer side (viewing side) of the half mirror 6, but since the half mirror 6 is in the form of a film, a transparent resin plate for support is required. Become. The hard coat treatment is performed for the purpose of scratch prevention, antifouling, antibacterial, etc. Even when the top cover 7 is arranged on the outside, it is preferable to apply the hard coat treatment to the top cover 7 .
　ハーフミラー６は、入射された光の半分程度を反射し、残りの半分程度を透過させる性質を有した光学部材である。トップカバー７は、透明材料により形成され、ハーフミラー６を保護するためのものである。なお、トップカバー７の透過度を下げることにより、外部から空中表示装置１の内部が見えづらくなり、空中表示だけを見やすくすることができる。また、再帰反射シート５とハーフミラー６とは、互いに少し傾けて配置されるものであってもよい。 The half mirror 6 is an optical member that has the property of reflecting about half of the incident light and transmitting about the remaining half. The top cover 7 is made of transparent material and serves to protect the half mirror 6 . By reducing the transmittance of the top cover 7, it becomes difficult to see the inside of the aerial display device 1 from the outside, and only the aerial display can be seen easily. Also, the retroreflective sheet 5 and the half mirror 6 may be arranged with a slight inclination to each other.
　また、ハーフミラー６の裏側には、発光パターンごとに、上下（Ｙ軸方向）に一対のセンサ電極１４Ａ、１４Ｂが設けられている。センサ電極１４Ａ、１４Ｂ間に電圧を印加することで、センサ電極１４Ａ、１４Ｂ間に電気力線が生じ、ユーザが指Ｆで空中表示Ｉを触れる過程で、接地レベルにある指Ｆにより電気力線に変化を生じさせ、その変化から空中表示Ｉへのタッチを検出することができる。ユーザの指Ｆは空中表示Ｉに触れるだけで、実在のボタン等に触れるわけではないので、衛生面において望ましいものとすることができる。なお、ＩＲ（赤外線）センサ等により指Ｆの空中表示Ｉへの接触が検出され、対応する機能のオン・オフ等が制御されるようにしてもよい。 Also, on the back side of the half mirror 6, a pair of sensor electrodes 14A and 14B are provided vertically (in the Y-axis direction) for each light emission pattern. By applying a voltage between the sensor electrodes 14A and 14B, electric lines of force are generated between the sensor electrodes 14A and 14B. , and a touch on the aerial display I can be detected from the change. Since the user's finger F only touches the aerial display I and does not touch an actual button or the like, it is desirable from a sanitary point of view. Note that an IR (infrared) sensor or the like may be used to detect the contact of the finger F with the aerial display I and control the on/off of the corresponding function.
　図２において、光源３２から導光板４、プリズムシート１５およびルーバーシート１０を介して出た光は再帰反射シート５の貫通孔５ａを通って経路Ｌ１で出る。なお、導光板４のドット光学素子、Ｖプリズム光学素子およびプリズムシート１５の調整により、表示面側のアイポイントＥＰが存在しない方向（図２における左下側）に光を出射し、アイポイントＥＰが存在する所定方向に出射する光（経路Ｌ０で出る光）を抑制するようにしている。アイポイントＥＰは、ユーザが目視することが想定される位置である。 In FIG. 2, light emitted from the light source 32 through the light guide plate 4, the prism sheet 15 and the louver sheet 10 passes through the through holes 5a of the retroreflective sheet 5 and exits along the path L1. By adjusting the dot optical element of the light guide plate 4, the V prism optical element, and the prism sheet 15, the light is emitted in a direction where the eye point EP on the display surface side does not exist (lower left side in FIG. 2), and the eye point EP is The existing light emitted in a predetermined direction (light emitted through the path L0) is suppressed. The eyepoint EP is a position that is assumed to be viewed by the user.
　再帰反射シート５の貫通孔５ａから経路Ｌ１で出た光は、半分程度がハーフミラー６で反射され、経路Ｌ２により再帰反射シート５に当たる。再帰反射シート５に当たった光は、入射角と同じ出射角で経路Ｌ３によりハーフミラー６に戻り、半分程度が透過する。再帰反射シート５のある貫通孔５ａから出た光は、経路Ｌ１の角度が変わっても幾何学的な関係から空中表示装置１外の同じ位置を通過するため、ハーフミラー６およびトップカバー７の外側に空中像による空中表示Ｉが行われ、ユーザのアイポイントＥＰから視認することができ、ユーザに指Ｆにより触れる動作を行わせることができる。 About half of the light emitted from the through hole 5a of the retroreflective sheet 5 along the path L1 is reflected by the half mirror 6 and hits the retroreflective sheet 5 along the path L2. The light that hits the retroreflective sheet 5 returns to the half mirror 6 along the path L3 at the same exit angle as the incident angle, and about half of the light is transmitted. Even if the angle of the path L1 changes, the light emitted from the through hole 5a of the retroreflective sheet 5 passes through the same position outside the aerial display device 1 because of the geometric relationship. An aerial display I by an aerial image is performed on the outside, and can be visually recognized from the user's eye point EP, and the user can be made to perform a touching action with the finger F.
　図４は、トイレ個室内における操作パネル１００の配置例を示す図である。操作パネル１００の前面には空中表示装置１が配置されている。図４においては、便座Ｔに腰かけた利用者Ｍが容易に手の届く壁Ｗ上の位置に操作パネル１００が設けられている。操作パネル１００の床面からの高さは例えば１ｍ、水平位置は利用者Ｍの膝の位置と同等である。このような操作パネル１００の配置に対し、日本人の平均座高を考慮すると、空中表示Ｉの垂直方向の視野範囲は、例えば、水平方向を基準として、上方向に１０deg～３５degとなる。空中表示Ｉの水平方向の視野範囲は、例えば±４０degとなる。 FIG. 4 is a diagram showing an arrangement example of the operation panel 100 in the private toilet room. An aerial display device 1 is arranged in front of the operation panel 100 . In FIG. 4, the operation panel 100 is provided at a position on the wall W within easy reach of the user M sitting on the toilet seat T. As shown in FIG. The height of the operation panel 100 from the floor surface is, for example, 1 m, and the horizontal position is equivalent to the position of the user M's knees. Considering the average sitting height of Japanese people with respect to such an arrangement of the operation panel 100, the vertical viewing range of the aerial display I is, for example, 10 degrees to 35 degrees above the horizontal direction. The horizontal viewing range of the aerial display I is, for example, ±40 degrees.
　図５Ａは、空中表示装置１の垂直方向および水平方向の配光の例を示す図であり、縦軸は垂直方向の配光角度（正面を０°）、横軸は水平方向の配光角度（正面を０°）である。図４の説明において配光について言及したが、中心輝度に対する各点の輝度の割合を考慮して、より厳密に配光を定めている。図５Ａにおいて、中心輝度は垂直方向が２３°、水平方向が０°の点における輝度であり、その中心輝度に対する輝度の割合が５０％以上となるべき点を黒丸で示し、割合が３０％以上となるべき点を黒四角で示している。 FIG. 5A is a diagram showing an example of vertical and horizontal light distribution of the aerial display device 1, where the vertical axis is the vertical light distribution angle (0° at the front) and the horizontal axis is the horizontal light distribution angle. (0° to the front). Although light distribution was mentioned in the description of FIG. 4, the light distribution is defined more strictly in consideration of the ratio of the luminance of each point to the central luminance. In FIG. 5A, the central luminance is the luminance at the point where the vertical direction is 23° and the horizontal direction is 0°, and the points where the ratio of luminance to the central luminance should be 50% or more are indicated by black circles, and the ratio is 30% or more. The black squares indicate the points where .
　図５Ｂは、導光板４等から構成される面状発光体の垂直方向および水平方向の配光の例を示す図であり、図５Ａと水平方向については同じで、垂直方向について角度の正負が逆になっている。これは、前述したとおり、ハーフミラー６による反射と再帰反射シート５による再帰反射とにより、面状発光体からの出射方向は空中表示が行われる方向とは対称的な関係になるからである。 FIG. 5B is a diagram showing an example of light distribution in the vertical and horizontal directions of a planar light emitter composed of the light guide plate 4 and the like. The horizontal direction is the same as in FIG. It's reversed. This is because, as described above, due to the reflection by the half mirror 6 and the retroreflection by the retroreflection sheet 5, the emission direction from the planar light emitter has a symmetrical relationship with the direction in which the aerial display is performed.
　図６は、面状発光体を構成する光源３２と導光板４の構成例を示す図である。図６において、左側は表示面の正面となる方向から見た図であり、右側は側面方向から見た図である。導光板４の入光側（入光側面４ａが設けられた側）は、ＲＧＢ－ＬＥＤによる光源３２の混色のために、例えば、全長３７ｍｍに対して、１０ｍｍの混色エリアが設けられている。この混色エリアには、出射のためのドット光学素子４ｄは設けられておらず、混色エリアの下の有効エリアにドット光学素子４ｄが設けられている。これは、ＲＧＢ－ＬＥＤのパッケージ内には赤・緑・青の発光素子が若干の間隔をおいて配置されているため、入光側面４ａに入光した直後に主面に出射させると、色別れが生じてしまうためである。 FIG. 6 is a diagram showing a configuration example of the light source 32 and the light guide plate 4 that constitute the planar light emitter. In FIG. 6, the left side is a view seen from the front of the display surface, and the right side is a view seen from the side. The light entrance side of the light guide plate 4 (the side where the light entrance side surface 4a is provided) is provided with a color mixing area of 10 mm with respect to the overall length of 37 mm for color mixing of the light source 32 by the RGB-LEDs. The dot optical element 4d for emission is not provided in this mixed color area, and the dot optical element 4d is provided in the effective area below the mixed color area. This is because the red, green, and blue light-emitting elements are arranged at small intervals in the RGB-LED package. This is because parting will occur.
　なお、導光板４の入光側面４ａに、光を拡散させるレンチキュラーレンズやプリズム等の光学素子が設けられることで、混色を短距離で済ませ、混色エリアの導光方向の長さを短くすることができる。また、導光板４の出射面側には、光源３２のピッチ方向の配光を制御するＶプリズム光学素子（レンチキュラーレンズも可）が設けられるが、これについては後述する。 By providing an optical element such as a lenticular lens or a prism for diffusing light on the light incident side surface 4a of the light guide plate 4, color mixing can be completed in a short distance, and the length of the light guide direction of the color mixing area can be shortened. can be done. A V-prism optical element (a lenticular lens is also possible) for controlling the light distribution in the pitch direction of the light source 32 is provided on the light emitting surface side of the light guide plate 4, which will be described later.
　図７は、面状発光体を構成する光源３２と導光板４の他の構成例を示す図である。図７において、右側の側面方向から見た図において、導光板４の厚さを変えた、楔形状の断面を有する２つのタイプを示している。Type-1は、光源３２のサイズに合わせるための厚さ（１ｍｍ）の入光側面４ａから混色エリアにおいて厚さを減少させ、有効エリアにおいて厚さを一定にしたものである。Type-2は、光源３２のサイズに合わせるための厚さ（１ｍｍ）の入光側面４ａから終端側まで厚さを減少させたものである。なお、Type-2において、ドット光学素子４ｄが設けられる裏面側が傾斜面となっている。 FIG. 7 is a diagram showing another configuration example of the light source 32 and the light guide plate 4 that constitute the planar light emitter. In FIG. 7, two types having a wedge-shaped cross section with different thicknesses of the light guide plate 4 are shown in the right side view. In Type-1, the thickness is reduced in the mixed color area from the incident side surface 4a having a thickness (1 mm) to match the size of the light source 32, and the thickness is constant in the effective area. Type-2 has a thickness (1 mm) to match the size of the light source 32, and the thickness is reduced from the incident side surface 4a to the terminal end side. In Type-2, the back side on which the dot optical element 4d is provided is an inclined surface.
　図８は、図７のType-1とType-2とによる、導光板４の終端の厚さに対する出射光束の変化の例を示す図である。図８において、導光板４の終端の厚さが薄い領域では、Type-2の方が出射光束が大きく、好ましい。これは、Type-1では、入光側面４ａから厚さが減少して一定になるまでの部分で光の反射の角度が変わってしまい、配光制御できない光が発生してしまうことによる。 FIG. 8 is a diagram showing an example of changes in emitted light flux with respect to the thickness of the terminal end of the light guide plate 4 according to Type-1 and Type-2 in FIG. In FIG. 8, Type-2 is preferable in the area where the thickness of the terminal end of the light guide plate 4 is thin, because the emitted light flux is larger. This is because, in Type-1, the angle of light reflection changes in the portion from the light incident side surface 4a until the thickness decreases and becomes constant, and light whose light distribution cannot be controlled is generated.
　図９は、面状発光体を構成する導光板４単体での導光方向の配光角度に対する輝度の例を示す図であり、図７におけるType-2の導光板４によるものである。図９において、４つの曲線は、導光板４の裏面に設けられるドット光学素子４ｄの接触角（ドットを形成する球面の端部の接線と、ドットが設けられる平面とのなす角度）に対応している。実線は接触角が１０°、破線は接触角が２０°、一点二短鎖線は接触角が３０°、二点鎖線は接触角が４０°の場合である。図９の中央付近に示された矩形状の破線のエリアは、面状発光体に要求される垂直方向の配光の範囲（図５Ｂ）に対応するものであり、ドット光学素子４ｄだけでは十分に垂直方向の配光が制御できていないことがわかる。そのため、プリズムシート１５が設けられることになる。 FIG. 9 is a diagram showing an example of the luminance with respect to the light distribution angle in the light guide direction of the light guide plate 4 alone constituting the planar light emitter, and is based on the Type-2 light guide plate 4 in FIG. In FIG. 9, the four curves correspond to the contact angle of the dot optical element 4d provided on the back surface of the light guide plate 4 (the angle formed by the tangent to the edge of the spherical surface forming the dots and the plane on which the dots are provided). ing. The solid line is for a contact angle of 10°, the dashed line is for a contact angle of 20°, the one-dot-two chain line is for a contact angle of 30°, and the two-dot chain line is for a contact angle of 40°. The rectangular broken line area shown near the center of FIG. 9 corresponds to the vertical light distribution range (FIG. 5B) required for the planar light emitter, and the dot optical element 4d alone is sufficient. It can be seen that the light distribution in the vertical direction cannot be controlled. Therefore, the prism sheet 15 is provided.
　図１０は、面状発光体を構成する光源３２と導光板４とプリズムシート１５の構成例を示す図である。図１０において、左側の表示面の正面となる方向から見た図では、光源３２の配列ピッチ方向の配光を制御するＶプリズム光学素子４ｅが設けられている。Ｖプリズム光学素子４ｅは、部分的な拡大図に示されるように、三角形状の凹凸面を有している。なお、前述のように、Ｖプリズム光学素子４ｅは円弧形状の断面を有するレンチキュラーレンズに代替が可能である。 FIG. 10 is a diagram showing a configuration example of the light source 32, the light guide plate 4, and the prism sheet 15 that constitute the planar light emitter. In FIG. 10, a V-prism optical element 4e is provided for controlling the light distribution in the pitch direction of the arrangement of the light sources 32 when viewed from the front of the display surface on the left side. The V-prism optical element 4e has a triangular concavo-convex surface as shown in a partially enlarged view. As described above, the V-prism optical element 4e can be replaced by a lenticular lens having an arc-shaped cross section.
　また、図１０において、右側の側面方向から見た図において、プリズムシート１５として、プリズム光学素子１５ａの設けられた面を導光板４側にしたType-3と、プリズム光学素子１５ａの設けられた面を出射面側にしたType-4とが示されている。図１１は、図１０のType-3のプリズムシート１５による光の屈折と全反射の例を示す図である。図１１において、入射した光Ｌ１１は屈折して光Ｌ１２となり、更に屈折して光Ｌ１３として出射する。また、光Ｌ２１は内部に入射した後に全反射により光Ｌ２２となり、更に屈折して光Ｌ２３として出射する。図１０のType-3とType-4とを比べると、Type-4ではType-3よりも配光が広くなり、アイポイント方向へ出射する光が多くなって、好ましくない。よって、Type-3がより好ましい。 In FIG. 10, as seen from the right side direction, as the prism sheet 15, Type-3 with the surface provided with the prism optical element 15a facing the light guide plate 4, and Type-4 is shown with the surface on the exit surface side. FIG. 11 is a diagram showing an example of refraction and total reflection of light by the Type-3 prism sheet 15 of FIG. In FIG. 11, incident light L11 is refracted to become light L12, and further refracted to emerge as light L13. Further, the light L21 enters the inside, becomes light L22 by total reflection, is further refracted, and is emitted as light L23. Comparing Type-3 and Type-4 in FIG. 10, Type-4 has a wider light distribution than Type-3, and more light is emitted in the direction of the eye point, which is not preferable. Therefore, Type-3 is more preferable.
　図１２は、導光板４の出射面側に設けられるＶプリズム光学素子４ｅの最適化されたより具体的な例を示す図である。図１２において、Ｖプリズム光学素子４ｅの断面形状の三角形の底辺の長さは１００μｍ、両端の底角は１０°、頂角は１６０°としている。 FIG. 12 is a diagram showing a more specific optimized example of the V-prism optical element 4e provided on the exit surface side of the light guide plate 4. FIG. In FIG. 12, the length of the base of the triangular cross section of the V-prism optical element 4e is 100 μm, the base angle of both ends is 10°, and the apex angle is 160°.
　図１３は、導光板４の反出射面側に設けられるドット光学素子４ｄとプリズムシート１５の反出射面側に設けられるプリズム光学素子１５ａの最適化されたより具体的な例を示す図である。図１３において、導光板４のドット光学素子４ｄの接触角は２９．６°、底部の直径は４０μｍ、高さは５．２μｍとなっている。また、プリズムシート１５のプリズム光学素子１５ａの上側の底角は７４．４°、頂角は７５°、ピッチは５０μｍとなっている。 FIG. 13 is a diagram showing a more specific optimized example of the dot optical element 4d provided on the reflective emission surface side of the light guide plate 4 and the prism optical element 15a provided on the reflective emission surface side of the prism sheet 15. In FIG. 13, the dot optical element 4d of the light guide plate 4 has a contact angle of 29.6°, a bottom diameter of 40 μm, and a height of 5.2 μm. The base angle of the upper side of the prism optical element 15a of the prism sheet 15 is 74.4°, the apex angle is 75°, and the pitch is 50 μm.
　図１４は、最適化された導光板４等から構成される面状発光体の配光の例を示す図であり、縦軸は垂直方向の配光角度（正面を０°）、横軸は水平方向の配光角度（正面を０°）である。図中の破線で囲まれた矩形の領域は、図５Ｂにおける割合が３０％になる領域に対応している。各配光角度における輝度（［ｃｄ／ｍ２］）と、中心輝度に対する輝度の割合（［％］）は、次の表１のようになる。なお、ルーバーシート１０は設けられていないものとしている。表１から明らかなように、図５Ｂの配光の要件は満たされている。 FIG. 14 is a diagram showing an example of the light distribution of a planar light emitter composed of the optimized light guide plate 4 and the like. It is a horizontal light distribution angle (0° at the front). A rectangular area surrounded by a dashed line in the figure corresponds to the area where the ratio is 30% in FIG. 5B. The luminance at each light distribution angle ([cd/m 2 ]) and the ratio of luminance to the central luminance ([%]) are shown in Table 1 below. It is assumed that the louver sheet 10 is not provided. As can be seen from Table 1, the requirements for the light distribution of Figure 5B are met.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　図１５は、最適化された導光板４等から構成される面状発光体の導光方向の配光角度に対する輝度の例を示す図である。なお、ルーバーシート１０は設けられていないものとしている。図１５において、実線の曲線は最適化された前述のType-3の場合を示しており、破線の曲線は比較のためにプリズム面を出射側にしたType-4の場合を示している。図中の－３０°付近の破線で囲まれた矩形の領域は、図５Ｂの割合が３０％になる領域（ターゲットエリア）に対応している。また、０°以上の破線で囲まれた矩形の領域は、アイポイント方向に直接に出射される光であり、できるだけ小さく抑えたい光である。 FIG. 15 is a diagram showing an example of luminance with respect to the light distribution angle in the light guiding direction of a planar light emitter composed of the optimized light guide plate 4 and the like. It is assumed that the louver sheet 10 is not provided. In FIG. 15, the solid-line curve indicates the case of the above-mentioned optimized Type-3, and the broken-line curve indicates the case of Type-4 with the prism surface on the output side for comparison. A rectangular area surrounded by a dashed line near -30° in the figure corresponds to the area (target area) where the ratio is 30% in FIG. 5B. A rectangular area surrounded by dashed lines of 0° or more is light that is directly emitted in the direction of the eyepoint, and is light that should be suppressed as small as possible.
　図１５から明らかなように、ターゲットエリアではType-4の方が輝度が高くなるが、アイポイント方向に直接に出射される光も大きくなり、好ましくない。この点、実線で示されたType-3の場合、アイポイント方向に直接に出射される光は、充分に抑制されたものとなっている。なお、Type-3の場合でもアイポイント方向に直接に出射される光は若干残るため、その部分の除去が要求される場合、ルーバーシート１０が用いられる。ルーバーシート１０は、ターゲットエリアの方向の光を通過させ、それ以外の方向の光を抑制する。 As is clear from FIG. 15, the brightness of Type-4 is higher in the target area, but the amount of light directly emitted in the direction of the eye point is also increased, which is not preferable. In this regard, in the case of Type-3 indicated by the solid line, the light emitted directly in the direction of the eyepoint is sufficiently suppressed. Even in the case of Type-3, since some light directly emitted in the direction of the eyepoint remains, the louver sheet 10 is used when that portion needs to be removed. The louver sheet 10 passes light in the direction of the target area and suppresses light in other directions.
　図１６は、比較例となる空中表示装置１’の例を示す表示面側から見た図である。図１７は、図１６におけるＸ－Ｘ断面図である。図１６および図１７において、空中表示装置１’は、略矩形状の開口２ａ’が形成されたフレーム２’内に、面状発光体を構成する線状光源３’と導光板４’とが配置されている。線状光源３’は、導光板４’の入光側面４ａ’の長手方向（Ｘ軸方向）に沿って線状に発光する光源であり、ＬＥＤ等の光源の他に、ポリカーボネートやアクリル等の透明材料による成形品のライトバーとプリズムバーとを含んでいる。導光板４’は、同様に、ポリカーボネートやアクリル等の透明材料により形成され、入光側面４ａ’から入射された光を終端側まで導き、裏面（非表示面）側に設けられた、光学素子により形成される発光部４ｂ’により光を反射する。なお、発光部４ｂ’の光学素子の調整により、表示面側のアイポイントＥＰ’が存在しない方向（図１７における左下側）に光を出射し、アイポイントＥＰ’が存在する所定方向に出射する光を抑制するようにしている。 FIG. 16 is a view from the display surface side showing an example of an aerial display device 1' serving as a comparative example. 17 is a cross-sectional view taken along the line XX in FIG. 16. FIG. In FIGS. 16 and 17, an aerial display device 1' has a linear light source 3' and a light guide plate 4' which constitute a planar light emitter in a frame 2' having a substantially rectangular opening 2a'. are placed. The linear light source 3' is a light source that emits linear light along the longitudinal direction (X-axis direction) of the light incident side surface 4a' of the light guide plate 4'. It includes a light bar and a prism bar molded out of transparent material. The light guide plate 4' is similarly formed of a transparent material such as polycarbonate or acrylic, guides the light incident from the light incident side surface 4a' to the end side, and is provided on the rear surface (non-display surface) side. Light is reflected by the light-emitting portion 4b' formed by. By adjusting the optical element of the light emitting unit 4b', the light is emitted in a direction where the eye point EP' on the display surface side does not exist (lower left side in FIG. 17), and is emitted in a predetermined direction where the eye point EP' exists. I try to keep the light out.
　また、導光板４’の発光部４ｂ’は、後述する再帰反射シート５’における、空中表示する図形を表すのに用いられる可能性のある複数の貫通孔５ａ’の位置を余裕をもってカバー（貫通孔５ａ’の周囲の所定範囲もカバー）する略矩形状の領域（表示面側から見た形状）を発光するか、または、再帰反射シート５’の１または複数の貫通孔５ａ’に対応する位置を余裕をもってカバー（貫通孔５ａ’の周囲の所定範囲もカバー）する領域を発光するものとする。また、フレーム２’の非表示面側には、開口２ａ’を覆うように、反射シート８’が配置されており、導光板４’から背面側へ漏れる光を導光板４’に戻すことで、光効率を高め、輝度を高めている。 In addition, the light-emitting portion 4b' of the light guide plate 4' covers the positions of a plurality of through-holes 5a' that may be used to represent a figure to be displayed in the air in the retroreflective sheet 5' described later. A substantially rectangular area (shape viewed from the display surface side) that also covers a predetermined range around the hole 5a' or corresponds to one or more through holes 5a' of the retroreflective sheet 5'. It is assumed that light is emitted in an area that covers the position with a margin (a predetermined range around the through hole 5a' is also covered). Further, on the non-display surface side of the frame 2', a reflective sheet 8' is arranged so as to cover the opening 2a'. , which increases light efficiency and brightness.
　また、導光板４’の出射面側には、発光部４ｂ’に対応する位置に空中表示する図形を表した複数の貫通孔５ａ’を有する再帰反射シート５’が、反射面を出射面側（導光板４’とは反対側）に向けて配置されている。また、フレーム２’の表示面側には、開口２ａ’を覆うようにハーフミラー６’が配置され、ハーフミラー６’にはトップカバー７’が外側に重ねられている。 Further, on the exit surface side of the light guide plate 4′, a retroreflective sheet 5′ having a plurality of through-holes 5a′ representing figures to be displayed in the air at positions corresponding to the light emitting parts 4b′ is provided so that the reflection surface is on the exit surface side. It is arranged toward (the side opposite to the light guide plate 4'). A half mirror 6' is arranged on the display surface side of the frame 2' so as to cover the opening 2a', and a top cover 7' is superimposed on the outside of the half mirror 6'.
　図１７において、面状発光体を構成する導光板４’の発光部４ｂ’から出た光は再帰反射シート５’の貫通孔５ａ’を通って経路Ｌ１’で出る。この光は、半分程度がハーフミラー６’で反射され、経路Ｌ２’により再帰反射シート５’に当たる。再帰反射シート５’に当たった光は、入射角と同じ出射角で経路Ｌ３’によりハーフミラー６’に戻り、半分程度が透過する。発光部４ｂ’のある点から出た光は、経路Ｌ１’の角度が変わっても幾何学的な関係から空中表示装置１’外の同じ位置を通過するため、ハーフミラー６’およびトップカバー７’の外側に空中像による空中表示Ｉ’が行われ、ユーザのアイポイントＥＰ’から視認することができ、ユーザに指Ｆ’により触れる動作を行わせることができる。 In FIG. 17, the light emitted from the light emitting portion 4b' of the light guide plate 4', which constitutes the planar light emitter, passes through the through hole 5a' of the retroreflective sheet 5' and emerges along the path L1'. About half of this light is reflected by the half mirror 6' and strikes the retroreflective sheet 5' along the path L2'. The light striking the retroreflective sheet 5' returns to the half mirror 6' along the path L3' at the same exit angle as the incident angle, and about half of the light is transmitted. Even if the angle of the path L1' changes, the light emitted from a certain point of the light emitting part 4b' passes through the same position outside the aerial display device 1' due to the geometric relationship. An aerial display I' by an aerial image is performed on the outside of ', can be visually recognized from the user's eye point EP', and can cause the user to perform a touching action with the finger F'.
　図１６および図１７の比較例の空中表示装置１’では、再帰反射シート５’の貫通孔５ａ’による全ての発光パターンについて１つの導光板４’の発光部４ｂ’により光を供給するものであるため、発光パターンごとに明るさや色を変えることは困難であった。この点、図１～図１５の実施形態の空中表示装置１によれば、発光パターンごとに面状発光体が設けられるため、発光パターンごとに明るさや色を変えることが容易になる。 In the floating display device 1' of the comparative example shown in FIGS. 16 and 17, light is supplied from the light emitting portion 4b' of one light guide plate 4' for all the light emission patterns of the through holes 5a' of the retroreflective sheet 5'. Therefore, it was difficult to change the brightness and color for each light emission pattern. In this respect, according to the aerial display device 1 of the embodiments of FIGS. 1 to 15, since the planar light emitter is provided for each light emission pattern, it becomes easy to change the brightness and color for each light emission pattern.
　また、図１６および図１７の比較例の空中表示装置１’では、面状発光体が線状光源３’と導光板４’とから構成され、線状光源３’は、ライトバーとプリズムバーとを含んでいるため、成形品の種類が多く、金型の種類が多くなるため、コストダウンが困難となる。この点、図１～図１５の実施形態の空中表示装置１によれば、成形品は導光板４だけとなるため、導光板４が複数であっても１つの金型から製造が可能であり、金型の種類の減少によりコストダウンを図ることができる。また、実施形態の空中表示装置１によれば、光源３２にＲＧＢ－ＬＥＤを用いているため、空中表示の色の制御が容易となるとともに薄型化を図ることができる。 16 and 17, the planar light emitter is composed of a linear light source 3' and a light guide plate 4', and the linear light source 3' is composed of a light bar and a prism bar. Since there are many types of molded products and many types of molds, it is difficult to reduce costs. In this respect, according to the aerial display device 1 of the embodiment of FIGS. 1 to 15, the molded product is only the light guide plate 4, so even if there are a plurality of light guide plates 4, it can be manufactured from one mold. , cost reduction can be achieved by reducing the number of types of molds. Further, according to the aerial display device 1 of the embodiment, since the RGB-LED is used for the light source 32, it is possible to easily control the color of the aerial display and to achieve a thin device.
　以上、本発明の実施形態について説明したが、本発明は上記実施形態に限定されるものではなく、その趣旨を逸脱しない限りにおいて種々の変更が可能である。 Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications are possible without departing from the spirit of the present invention.
　以上のように、実施形態に係る空中表示装置は、空中表示する図形を表した複数の貫通孔を有する再帰反射シートと、再帰反射シートの貫通孔による発光パターンごとに、再帰反射シートの裏面側に配置される複数の面状発光体と、再帰反射シートの出射面側に配置されたハーフミラーとを備える。これにより、固定的な発光パターンを空中表示するのに適し、発光パターンごとに明るさや色を変えることができる。 As described above, the aerial display device according to the embodiment includes a retroreflective sheet having a plurality of through-holes representing figures to be displayed in mid-air, and light emitting patterns formed by the through-holes of the retroreflective sheet. and a half-mirror arranged on the exit surface side of the retroreflective sheet. This makes it suitable for displaying a fixed light emission pattern in the air, and allows the brightness and color to be changed for each light emission pattern.
　また、面状発光体は、複数の点状の光源と、入光側面が前記複数の点状の光源に対向し、一方の主面にドット光学素子が設けられた導光板と、導光板の出射面側に配置され、導光方向の配光を制御するプリズムシートとを備える。これにより、成形品が１種類の金型で製造できる導光板だけで済むため、コストダウンを図ることができる。また、線状光源を用いなくても、輝度の均一性が図れ、所望の配光に制御することができる。 Further, the planar light emitter includes a plurality of point-like light sources, a light guide plate having a light incident side surface facing the plurality of point-like light sources and having dot optical elements provided on one main surface, and a light guide plate. and a prism sheet that is arranged on the exit surface side and controls the light distribution in the light guide direction. As a result, only the light guide plate, which can be manufactured with one type of mold, is enough for the molded product, so that the cost can be reduced. In addition, even without using a linear light source, it is possible to achieve uniformity in brightness and control the light distribution to a desired level.
　また、導光板は、他方の主面に複数の点状の光源のピッチ方向の配光を制御するＶプリズムまたはレンチキュラーレンズからなる光学素子が設けられる。これにより、光源に依存せずにピッチ方向の配光を制御することができる。 Also, the light guide plate is provided with an optical element consisting of a V-prism or a lenticular lens for controlling the light distribution in the pitch direction of the plurality of point-like light sources on the other principal surface. Thereby, the light distribution in the pitch direction can be controlled independently of the light source.
　また、複数の点状の光源は、それぞれ、赤・緑・青の発光素子を内部に有するＲＧＢ－ＬＥＤである。これにより、空中表示の色の制御が容易となるとともに薄型化を図ることができる。 Also, the plurality of point-like light sources are RGB-LEDs each having red, green, and blue light-emitting elements inside. As a result, it is possible to easily control the color of the aerial display and to reduce the thickness of the device.
　また、導光板は、入光側に、混色のための、ドット光学素子が設けられない混色エリアを有する。これにより、充分な混色が行われ、色別れを防止することができる。 In addition, the light guide plate has, on the light incident side, a color mixing area in which dot optical elements are not provided for color mixing. Thereby, sufficient color mixing is performed, and color separation can be prevented.
　また、導光板の入光側面には、光を拡散させる他の光学素子が設けられる。これにより、混色のための混色エリアの導光方向の長さを短くすることができる。 In addition, another optical element for diffusing light is provided on the light incident side surface of the light guide plate. As a result, the length of the color mixing area for color mixing in the light guiding direction can be shortened.
　また、導光板は、入光側の厚さよりも終端側の厚さが薄い楔形状の断面を有する。これにより、光源のサイズに応じた入光側の厚さを確保しつつ無駄な厚さを削減することができ、出射効率を向上させることができる。 In addition, the light guide plate has a wedge-shaped cross section in which the thickness on the terminal side is thinner than the thickness on the light incident side. As a result, it is possible to reduce unnecessary thickness while ensuring the thickness on the light incident side according to the size of the light source, and to improve the output efficiency.
　また、プリズムシートのプリズム面は、導光板側の面または出射面側の面に設けられる。これにより、プリズム面が導光板側の面に設けられる場合は、出射面側にプリズム面が設けられる場合に比べて配光を狭くすることができ、アイポイント方向への出射光を減らすことができる。また、プリズム面が出射面側の面に設けられる場合は、若干の性能低下はあるが、充分に実用に耐えるものとすることができる。 Also, the prism surface of the prism sheet is provided on the light guide plate side surface or the exit surface side surface. As a result, when the prism surface is provided on the light guide plate side, the light distribution can be narrowed compared to when the prism surface is provided on the exit surface side, and the emitted light in the direction of the eye point can be reduced. can. Further, when the prism surface is provided on the surface on the output surface side, the performance is slightly degraded, but it can be sufficiently put into practical use.
　また、面状発光体は、出射面側に配置されたルーバーシートを備える。これにより、アイポイント方向への出射光をよりいっそう減らすことができる。 In addition, the planar light emitter includes a louver sheet arranged on the exit surface side. As a result, the emitted light in the eyepoint direction can be further reduced.
　また、上記実施の形態により本発明が限定されるものではない。上述した各構成要素を適宜組み合わせて構成したものも本発明に含まれる。また、さらなる効果や変形例は、当業者によって容易に導き出すことができる。よって、本発明のより広範な態様は、上記の実施の形態に限定されるものではなく、様々な変更が可能である。 In addition, the present invention is not limited by the above-described embodiment. The present invention also includes those configured by appropriately combining the respective constituent elements described above. Further effects and modifications can be easily derived by those skilled in the art. Therefore, broader aspects of the present invention are not limited to the above-described embodiments, and various modifications are possible.
　１　空中表示装置，２　フレーム，２ａ　開口，２ｂ　底面，３１　基板，３２　光源，４　導光板，４ａ　入光側面，４ｄ　ドット光学素子，４ｅ　Ｖプリズム光学素子，５　再帰反射シート，５ａ　貫通孔，６　ハーフミラー，７　トップカバー，８　反射シート，１０　ルーバーシート，１４Ａ、１４Ｂ　センサ電極，１５　プリズムシート，１５ａ　プリズム光学素子，１６　光源制御基板，ＥＰ　アイポイント，Ｉ　空中表示，Ｆ　指 1 aerial display device, 2 frame, 2a aperture, 2b bottom surface, 31 substrate, 32 light source, 4 light guide plate, 4a light incident side surface, 4d dot optical element, 4e V prism optical element, 5 retroreflective sheet, 5a through hole, 6 Half mirror, 7 Top cover, 8 Reflection sheet, 10 Louver sheet, 14A, 14B Sensor electrode, 15 Prism sheet, 15a Prism optical element, 16 Light source control board, EP Eye point, I Air display, F Finger

Claims (9)

  1. 　空中表示する図形を表した複数の貫通孔を有する再帰反射シートと、
    　前記再帰反射シートの前記貫通孔による発光パターンごとに、前記再帰反射シートの裏面側に配置される複数の面状発光体と、
    　前記再帰反射シートの出射面側に配置されたハーフミラーと、
    を備える空中表示装置。     a retroreflective sheet having a plurality of through-holes representing figures to be displayed in the air;
    a plurality of planar light emitters arranged on the back side of the retroreflective sheet for each light emission pattern formed by the through holes of the retroreflective sheet;
    a half mirror disposed on the exit surface side of the retroreflective sheet;
    An aerial display device comprising:
  2. 　前記面状発光体は、
    　複数の点状の光源と、
    　入光側面が前記複数の点状の光源に対向し、一方の主面にドット光学素子が設けられた導光板と、
    　前記導光板の出射面側に配置され、導光方向の配光を制御するプリズムシートと、
    を備える請求項１に記載の空中表示装置。     The planar light emitter is
    a plurality of point light sources;
    a light guide plate having a light incident side surface facing the plurality of point light sources and having a dot optical element provided on one principal surface;
    a prism sheet arranged on the light emitting surface side of the light guide plate for controlling light distribution in the light guide direction;
    The aerial display device of claim 1, comprising:
  3. 　前記導光板は、他方の主面に前記複数の点状の光源のピッチ方向の配光を制御するＶプリズムまたはレンチキュラーレンズからなる光学素子が設けられる、
    請求項２に記載の空中表示装置。     The light guide plate is provided with an optical element consisting of a V prism or a lenticular lens for controlling light distribution in the pitch direction of the plurality of point light sources on the other principal surface.
    3. The aerial display device according to claim 2.
  4. 　前記複数の点状の光源は、それぞれ、赤・緑・青の発光素子を内部に有するＲＧＢ－ＬＥＤである、
    請求項２または３に記載の空中表示装置。     The plurality of point-like light sources are RGB-LEDs each having red, green, and blue light emitting elements inside,
    4. An aerial display device according to claim 2 or 3.
  5. 　前記導光板は、入光側に、混色のための、前記ドット光学素子が設けられない混色エリアを有する、
    請求項４に記載の空中表示装置。     The light guide plate has a color mixing area on the light entrance side for color mixing in which the dot optical element is not provided.
    An aerial display device according to claim 4.
  6. 　前記導光板の入光側面には、光を拡散させる他の光学素子が設けられる、
    請求項５に記載の空中表示装置。     Another optical element for diffusing light is provided on the light entrance side of the light guide plate.
    An aerial display device according to claim 5 .
  7. 　前記導光板は、入光側の厚さよりも終端側の厚さが薄い楔形状の断面を有する、
    請求項２～６のいずれか一つに記載の空中表示装置。     The light guide plate has a wedge-shaped cross section in which the thickness on the terminal side is thinner than the thickness on the light incident side.
    An aerial display device according to any one of claims 2 to 6.
  8. 　前記プリズムシートのプリズム面は、前記導光板側の面または出射面側の面に設けられる、
    請求項２～７のいずれか一つに記載の空中表示装置。     The prism surface of the prism sheet is provided on the light guide plate side surface or the exit surface side surface.
    An aerial display device according to any one of claims 2 to 7.
  9. 　前記面状発光体は、出射面側に配置されたルーバーシートを備える、
    請求項１～８のいずれか一つに記載の空中表示装置。     The planar light emitter comprises a louver sheet arranged on the output surface side,
    An aerial display device according to any one of claims 1 to 8.
PCT/JP2022/005108 2021-03-12 2022-02-09 Aerial display apparatus WO2022190751A1 (en)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08272326A (en) * 1995-02-08 1996-10-18 Asutei Kk Signal mirror
US20140226212A1 (en) * 2011-08-02 2014-08-14 De La Rue International Limited Security devices
KR101663757B1 (en) * 2015-11-27 2016-10-17 (주)이케이엘이디 Solar-powered self luminous traffic signs
JP2017107165A (en) * 2015-12-07 2017-06-15 国立大学法人宇都宮大学 Display device and display method of aerial image
JP2018081138A (en) * 2016-11-14 2018-05-24 日本カーバイド工業株式会社 Image display unit
JP2021144071A (en) * 2020-03-10 2021-09-24 ミネベアミツミ株式会社 Aerial display device

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08272326A (en) * 1995-02-08 1996-10-18 Asutei Kk Signal mirror
US20140226212A1 (en) * 2011-08-02 2014-08-14 De La Rue International Limited Security devices
KR101663757B1 (en) * 2015-11-27 2016-10-17 (주)이케이엘이디 Solar-powered self luminous traffic signs
JP2017107165A (en) * 2015-12-07 2017-06-15 国立大学法人宇都宮大学 Display device and display method of aerial image
JP2018081138A (en) * 2016-11-14 2018-05-24 日本カーバイド工業株式会社 Image display unit
JP2021144071A (en) * 2020-03-10 2021-09-24 ミネベアミツミ株式会社 Aerial display device

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