JP2022139533A - Aerial display device - Google Patents

Abstract

To provide an aerial display device that can perform an appropriate aerial display.SOLUTION: An aerial display device according to an embodiment includes a retroreflection sheet, a transparent display device, and a half mirror. The transmission display device is arranged on a retroreflection surface side of the retroreflection sheet. The half mirror is arranged on a light exit surface side of the transparent display device. The transparent display device has a light guide plate with a light emitting unit for an aerially displayed drawing. The light emitting unit is formed of a recessed optical element of which cross-sectional shape is a V-shape, a polygon, or a top-flat arc shape.SELECTED DRAWING: Figure 2

Description

The present invention relates to an aerial display device.

An aerial display device in which a half mirror and a retroreflective sheet are arranged at an angle of 45° has been disclosed (see Patent Documents 1 to 5, for example). Further, an aerial display device is disclosed that includes a transparent light source, a retroreflective sheet, and a half mirror, which are arranged parallel to each other (see, for example, Patent Document 6, etc.). Further, an aerial display device is disclosed in which a light source having an inclined light-emitting surface that emits light obliquely between a half mirror and a retroreflective sheet that are arranged parallel to each other is arranged (see, for example, Patent Document 7, etc.).

JP 2019-129378 A JP-A-4-339488 Japanese Patent Publication No. 7-501161 Japanese Patent Publication No. 2001-511915 Japanese Patent Publication No. 2002-517779 WO2017/099116 JP 2019-200313 A

However, conventionally, the light distribution and luminance distribution of the aerial display have not been particularly considered, and the aerial display has not been sufficiently optimized.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an aerial display device capable of achieving appropriate aerial display.

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 transparent display device, and a half mirror. The transparent display device is arranged on the retroreflective surface side of the retroreflective sheet. The half mirror is arranged on the light exit surface side of the transparent display device. The transparent display device includes a light guide plate having a light-emitting portion corresponding to a figure to be displayed in the air, and the light-emitting portion is composed of a concave optical element having a V-shaped, polygonal, or top-flat arc-shaped cross section. be done.

An aerial display device according to an aspect of the present invention can optimize aerial display.

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 a diagram showing an example of display and operation of an operation panel using an aerial display device. FIG. 4 is a diagram showing an arrangement example of an operation panel in a private toilet room. FIG. 5 is a diagram showing an example of light distribution required for an aerial display device. FIG. 6 is a diagram (1) showing an example of the shape of the optical element of the light guide plate in the enlarged area of FIG. 7 is a diagram (2) showing an example of the shape of the optical element of the light guide plate in the enlarged area of FIG. 5. FIG. 8 is a diagram (3) showing an example of the shape of the optical element of the light guide plate in the enlarged area of FIG. 5. FIG. FIG. 9 is a diagram showing values defining a concave optical element (FIG. 6) having a V-shaped cross section as an example of the optical element. FIG. 10 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the angle A in FIG. 9 is changed. FIG. 11 is a diagram (1) showing values defining a concave optical element (FIG. 7) having a polygonal cross section as an example of the optical element. FIG. 12 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the angle A in FIG. 11 is fixed and the angle B is changed. FIG. 13 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the angle B in FIG. 11 is fixed and the angle A is changed. FIG. 14 is a diagram (2) showing values defining a concave optical element (FIG. 7) having a polygonal cross section as an example of the optical element. FIG. 15 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the width D in FIG. 14 is fixed and the ratio C is changed. FIG. 16 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the ratio C in FIG. 14 is fixed and the width D is changed. FIG. 17 is a diagram showing values defining a concave optical element (FIG. 8) having a top-flat arc shape in cross section as an example of the optical element. FIG. 18 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the contact angle A in FIG. 17 is fixed and the contact angle B is changed. FIG. 19 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the contact angle B in FIG. 17 is fixed and the contact angle A is changed. FIG. 20 is a diagram showing an example of a light-emitting portion using a linear optical element. FIG. 21 is a diagram showing an example of a light-emitting portion using a wave-shaped optical element. FIG. 22 is an illustration of a dark area produced by a linear optical element. FIG. 23 is a diagram (1) showing an example of a light-emitting portion using intermittent optical elements. FIG. 24 is a diagram (2) showing an example of a light-emitting portion using intermittent optical elements. FIG. 25 is a diagram showing an example of an aerial display device according to another embodiment, viewed from the display surface side. 26 is a cross-sectional view taken along the line XX in FIG. 25. FIG.

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.

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. The aerial display device 1 shown in FIGS. 1 and 2 is assumed to be used as an operation panel installed on the wall surface of a private toilet, and the display surface faces the horizontal direction.

1 and 2, an aerial display device 1 includes a linear light source 3 and a light guide plate 4, which constitute a transparent display device, arranged in a frame 2 having a substantially rectangular opening 2a. The linear light source 3 is a light source that emits linear light along the longitudinal direction of the light incident side surface 4 a of the light guide plate 4 . 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 emits light formed by an optical element provided on the back surface (non-display surface) side. The light is reflected by the portion 4b and emitted in a direction where the eyepoint EP on the display surface side does not exist (lower left side in FIG. 2). The eyepoint EP is a position that is assumed to be viewed by the user.

Further, a retroreflective sheet 5 is arranged on the non-display surface side of the frame 2 so as to cover the opening 2a with the reflective surface facing the light guide plate 4 side. The retroreflective sheet 5 is a sheet on which transparent minute glass beads or the like are arranged without gaps on the surface, and has the property of emitting incident light through the same path (the incident angle and the emitting angle are the same). As the retroreflection sheet 5, in addition to the glass bead sphere, the inner surface of the vertices of a cube, which is called a corner cube and is formed by combining three flat plates having the property of reflecting light at right angles to each other, is used. 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 superposed on the half mirror 6 to 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 element having a 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.

In FIG. 2, about half of the light emitted from the light emitting portion 4b of the light guide plate 4 constituting the transparent display device along the path L1 is reflected by the half mirror 6, passes through the light guide plate 4 along the path L2, and reaches the retroreflective sheet 5. hit. 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 a certain point of the light emitting part 4b passes through the same position outside the aerial display device 1 because of the geometric relationship. An image-based aerial display I is performed and can be viewed from the user's eyepoint EP.

FIG. 3 is a diagram showing an example of display and operation of the operation panel 100 using the aerial display device 1. As shown in FIG. In FIG. 3, an aerial display I corresponding to various switch buttons is performed from an operation panel 100 installed on a wall surface or the like in the toilet compartment. When the user touches one of the aerial displays I with the finger F, an IR (infrared) sensor or the like (not shown) provided on the operation panel 100 causes the finger F to contact the aerial display I (not a physical contact, but an aerial display). Entry of the finger F into the position where the display I is being performed) is detected, and ON/OFF of the corresponding function is controlled. 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.

FIG. 4 is a diagram showing an arrangement example of the operation panel 100 in the private toilet room. 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. FIG. 5 is a diagram showing an example of the light distribution required for the aerial display device 1. Considering the average sitting height of Japanese people with respect to the arrangement of the operation panel 100 described above, the vertical viewing range of the aerial display I is, for example, 10 deg to 35 deg. The horizontal viewing range of the aerial display I is, for example, ±40 degrees.

FIG. 6 is a diagram showing an example of the shape of the optical element 4c of the light guide plate 4 in the enlarged region R of FIG. FIG. 7 is a diagram showing another example of the shape of the optical element 4c of the light guide plate 4 in the enlarged region R of FIG. FIG. 8 is a diagram showing another example of the shape of the optical element 4c of the light guide plate 4 in the enlarged region R of FIG. Each shape is described in detail below. 6 to 8, the pitch at which the optical elements 4c are arranged is, for example, 0.1 mm. Note that the pitch value is not limited to this value.

FIG. 9 is a diagram showing values defining a concave optical element (FIG. 6) having a V-shaped cross section as an example of the optical element 4c. In FIG. 9, the optical element 4c is defined by a width D, an apex angle, and a base angle (angle A) on the light rising side. Here, the width D is 0.1 mm, the apex angle is 60 degrees, and the angle A is a variable.

FIG. 10 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the angle A in FIG. 9 is changed. Here, the vertical direction is the direction perpendicular to the output surface of the light guide plate 4, and the positive direction is the upward tilt, and the negative direction is the downward tilt from the vertical direction. In FIG. 10, the angle A=32 degrees is closest to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. Therefore, the width D=0.1 mm, the apex angle=60 degrees, and the angle A=32 degrees correspond to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. The horizontal visual field range of ±40 degrees is realized by light distribution in the horizontal direction by the linear light source 3 . By appropriately setting the light distribution in accordance with the environment in which it is used, it is possible to eliminate light emission in useless directions, increase light efficiency, and improve brightness.

FIG. 11 is a diagram showing values defining a concave optical element (FIG. 7) having a polygonal cross section as an example of the optical element 4c. In FIG. 11, the optical element 4c has a width D, an upper base angle (angle A), an upper apex angle (angle B), and an upper inclined surface relative to the vertical lengths of the upper and intermediate inclined surfaces. It is defined by the ratio of the vertical length of Here, the width D is set to 0.06 mm, the ratio of the vertical length of the upper inclined surface to the ratio of the vertical length of the upper and intermediate inclined surfaces is set to 0.5, and the angles A and B are variables. and

FIG. 12 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the angle A in FIG. 11 is fixed and the angle B is changed. In FIG. 12, the angle A is 40 degrees. FIG. 13 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the angle B in FIG. 11 is fixed and the angle A is changed. In FIG. 13, the angle B is 35 degrees.

In FIG. 12, the angle B=35 degrees is closest to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. In FIG. 13, the angle A=40 degrees is closest to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. Therefore, the width D = 0.06 mm, the ratio of the vertical length of the upper inclined surface to the vertical length of the upper and intermediate inclined surfaces = 0.5, the angle A = 40 deg, and the angle B = 35 deg, The value corresponds to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. By appropriately setting the light distribution in accordance with the environment in which it is used, it is possible to eliminate light emission in useless directions, increase light efficiency, and improve brightness.

FIG. 14 is a diagram showing other values defining a concave optical element (FIG. 7) having a polygonal cross section as an example of the optical element 4c. In FIG. 14, the optical element 4c is defined by the same dimensions, angles, etc. as in FIG. The base angle of the lower side is 88 deg, and the width D and the ratio (C) of the vertical length of the upper inclined surface to the ratio of the vertical length of the upper and intermediate inclined surfaces are used as variables. there is

FIG. 15 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the width D in FIG. 14 is fixed and the ratio C is changed. In FIG. 15, the width D is 0.06 mm. FIG. 16 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the ratio C in FIG. 14 is fixed and the width D is changed. In FIG. 16, the ratio C is set to 0.15.

In FIG. 15, the closest approximation to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. 5 is when the ratio C=0.15. In FIG. 16, the width D=0.06 mm is closest to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. Therefore, the width D = 0.06 mm, the upper base angle (angle A) = 40 deg, the upper apex angle (angle B) = 35 deg, the lower base angle = 88 deg, and the ratio C = 0.15 are obtained in FIG. The values correspond to the indicated vertical viewing range of 10 degrees to 35 degrees. By appropriately setting the light distribution in accordance with the environment in which it is used, it is possible to eliminate light emission in useless directions, increase light efficiency, and improve brightness.

FIG. 17 is a diagram showing values defining a concave optical element (FIG. 8) having a top-flat arc shape in cross section as an example of the optical element 4c. The top-flat arc shape is an arc shape with a flat tip. In FIG. 17, the optical element 4c is defined by a contact angle A on the surface side of the arc and a contact angle B on the tip (flat portion) side of the arc.

FIG. 18 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the contact angle A in FIG. 17 is fixed and the contact angle B is changed. In FIG. 18, the contact angle A is 50 degrees. FIG. 19 is a diagram showing an example of luminous intensity in a direction inclined from the vertical direction when the contact angle B in FIG. 17 is fixed and the contact angle A is changed. In FIG. 19, the contact angle B is 20 degrees.

In FIG. 18, the contact angle B=20 degrees is closest to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. In FIG. 19, the contact angle A=50 degrees is closest to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. Therefore, the contact angle A=50 degrees and the contact angle B=20 degrees correspond to the vertical viewing range of 10 degrees to 35 degrees shown in FIG. By appropriately setting the light distribution in accordance with the environment in which it is used, it is possible to eliminate light emission in useless directions, increase light efficiency, and improve brightness.

20A and 20B are diagrams showing an example of the light-emitting portion 4b formed by the linear optical element. The left side is a view from the display surface side, and the right side is a sectional view taken along the line XX in the left side. In FIG. 20, the V-shaped concave optical element 4c shown in FIG. 6 and the like is shown as an example, but the polygonal-shaped optical element shown in FIG. 7 and the top-flat arc-shaped optical element shown in FIG. 8 may also be used. . In FIG. 20, the groove of the optical element 4c forming the light-emitting portion 4b extends linearly and continuously in the horizontal direction (X-axis direction) of the figure. The horizontal direction (X-axis direction) is the extending direction of the linear light source 3 .

21A and 21B are diagrams showing an example of a light emitting portion 4b formed by a wave-shaped optical element, the left side being a view from the display surface side, and the right side being a cross-sectional view taken along the line XX in the left side. In FIG. 21, the V-shaped concave optical element 4c shown in FIG. 6 and the like is shown as an example, but the polygonal shape of FIG. 7 or the top flat arc shape of FIG. 8 may be used. . In FIG. 21, the groove of the optical element 4c forming the light-emitting portion 4b continuously extends in the lateral direction (X-axis direction) of the drawing while waving. The amplitude of the wave is, for example, 5 μm, the period is, for example, 1 mm, and the shape of the wave is sinusoidal. The grooves of the optical element 4c may extend continuously in the vertical direction (Z-axis direction) of the drawing while waving. Wave-like optics can reduce the occurrence of dark areas that occur with linear optics.

22A and 22B are explanatory diagrams of a dark area generated by a linear optical element. The left side is a diagram viewed from the display surface side, and the right side is a diagram viewed from the X-axis direction cross-sectional direction in the left diagram. In FIG. 22, for example, the portion of the optical element 4c corresponding to the leftmost square aerial display I in FIG. 3 is cut out and shown.

In FIG. 22, of the light coming from the upper linear light source 3 (not shown) and directed toward the user M, the light L11 that hits the optical element 4c at the left end of the light emitting section 4b is reflected and becomes light L12. A portion is emitted from the light guide plate 4 as light L13. Also, the remaining portion is reflected toward the inside as light L21, hits the lower optical element 4c, is reflected, becomes light L22, and is emitted as light L23. Therefore, the area on the side of the user M below the light L23 becomes darker than the areas above and to the left of it, and the display quality deteriorates. On the other hand, according to the wave-shaped optical element as shown in FIG. 21, since the light is reflected in multiple directions, it is possible to reduce the occurrence of darkened areas and improve the display quality.

23A and 23B are diagrams showing an example of the light-emitting portion 4b formed by intermittent optical elements. The left side is a view from the display surface side, and the right side is a cross-sectional view taken along the line XX in the left side. In FIG. 23, the grooves of the optical element 4c forming the light-emitting portion 4b intermittently extend in the horizontal direction (X-axis direction) of the figure. 23 shows an example in which the V-shaped concave optical element 4c shown in FIG. The arc-shaped optical element may be cut into a substantially rugby ball shape.

24A and 24B are diagrams showing another example of the light-emitting portion 4b using intermittent optical elements. The left side is a view from the display surface side, and the right side is a cross-sectional view taken along the line XX in the left side. In this example, instead of the rugby ball shape of FIG. 23, it has a rectangular shape. Also in this case, not only the V-shaped concave optical element 4c shown in FIG.

In the intermittent optical elements of FIGS. 23 and 24, light from the linear light source 3 above passes through the non-grooved portion of the optical element and easily reaches the bottom, and the light passing through is emitted by the optical element in the middle. is limited to decay, and the occurrence of darkened areas can be greatly reduced. The wavy optical element of FIG. 21 and the intermittent optical element of FIG. 23 or 24 may be applied at the same time.

FIG. 25 is a diagram showing an example of an aerial display device 1 according to another embodiment, viewed from the display surface side. 26 is a cross-sectional view taken along the line XX in FIG. 25. FIG. This embodiment prevents deterioration of the quality of the aerial display, such as unclear pattern boundaries in the aerial display and the appearance of multiple images. The problem that the light emitting portion is visible can be solved by light distribution control by the light emitting portion 4b of the light guide plate 4 shown in FIGS. 6 to 19. FIG. Also, the improvements described with reference to FIGS. 20 to 24 can be similarly applied.

25 and 26, an aerial display device 1 has a linear light source 3 and a light guide plate 4 that constitute a planar light emitter arranged in a frame 2 in which a substantially rectangular opening 2a is formed. 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 4 a of the light guide plate 4 . The light guide plate 4 is formed of a transparent material such as polycarbonate or acryl, guides the light incident from the light entrance side surface 4a to the end side, and emits light formed by an optical element provided on the back surface (non-display surface) side. Light is reflected by the portion 4b.

In the same manner as described above, by adjusting the optical element of the light emitting unit 4b, the light is emitted in a direction where the eye point EP does not exist on the display surface side (lower left side in FIG. He is trying to suppress the light emitted in the direction. The eyepoint EP is a position that is assumed to be viewed by the user.

In addition, the light-emitting portion 4b of the light guide plate 4 covers the positions of the plurality of through-holes 5a, which may be used to represent a figure to be displayed in the air, in the retroreflective sheet 5 described later (the periphery of the through-holes 5a). The light is emitted in a substantially rectangular area (shape viewed from the display surface side) that covers a predetermined range of the retroreflective sheet 5, or the position corresponding to one or more through holes 5a of the retroreflective sheet 5 is covered with a margin (through It is assumed that light is emitted from an area that also covers a predetermined range around the hole 5a. In the former case, the end portion of the light emitting portion 4b of the light guide plate 4 is set long in the light guide direction (Y-axis direction) from the position directly facing the outermost through hole 5a of the retroreflective sheet 5. FIG. This long end portion is set in consideration of light distribution, positional accuracy of members, etc., rather than the position where the optical axis extends in the opposite direction from the through hole 5a of the retroreflective sheet 5 and reaches the vicinity of the back side of the light guide plate 4. It is a position outside the . The light emitting portion 4b of the light guide plate 4 extends substantially across the entire width of the light guide plate 4 in the lateral direction (X-axis direction). In the latter case, the light-emitting portion 4b of the light guide plate 4 is set long in the light guide direction (Y-axis direction) and in the lateral direction (X-axis direction) for each through hole 5a of the retroreflective sheet 5 . In the former case, if the figure to be displayed in the air is to be changed, it is sufficient to change the through hole 5a of the retroreflective sheet 5, which facilitates the correspondence. Moreover, in the latter case, the light emitted from the light guide plate 4 can be narrowed down to the light necessary for display, so that the light efficiency can be improved.

A reflective sheet 8 is arranged on the non-display surface side of the frame 2 so as to cover the opening 2a. , increasing the brightness. The opening 2a may not be present on the non-display surface side of the frame 2 (it may be closed with a bottom plate), and the reflection sheet 8 may be provided on the non-display surface side of the light guide plate 4 .

Further, on the output 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 portions 4b is placed on the output surface side (light guide plate 4 opposite side). The retroreflective sheet 5 is a sheet on which transparent minute glass beads or the like are arranged without gaps on the surface, and has the property of emitting incident light through the same path (the incident angle and the emitting angle are the same). As the retroreflection sheet 5, in addition to glass bead spheres, a corner cube, which uses the inner surface of the vertices of a cube in which three surfaces having the property of reflecting light are combined at right angles to each other, is also used. can do. 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 superposed on the half mirror 6 to 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. Even when the top cover 7 is arranged on the outside, it is preferable to apply a hard coat treatment to the top cover 7 . The half mirror 6 is an optical element having a 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.

In FIG. 26, the light emitted from the light emitting portion 4b of the light guide plate 4 constituting 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 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 a certain point of the light emitting part 4b passes through the same position outside the aerial display device 1 because of the geometric relationship. An aerial display I by an image is performed 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.

One of the reasons for the above-mentioned "unclear pattern boundaries in the aerial display" is due to the processing method of the optical element 4c that constitutes the light emitting portion 4b of the light guide plate 4. FIG. That is, the optical element 4c is formed by cutting the light guide plate 4 with a cutting tool, or in the process of forming the light guide plate 4 with a mold in which ridges corresponding to the optical elements 4c are formed by a cutting tool. An optical element 4c is formed. As a result, the edge of the optical element 4c has a narrow width and a shallow depth, which reduces the amount of light reflected toward the exit surface side and makes the pattern boundary of the aerial display unclear. In this regard, in the embodiments of FIGS. 25 and 26, it is the through holes 5a of the retroreflective sheet 5 that define the pattern boundary of the aerial display, and the end of the optical element 4c that constitutes the light emitting portion 4b of the light guide plate 4 is Since the pattern boundary of the aerial display is not affected, the pattern boundary of the aerial display can be made clear.

In addition, as another cause of the above-mentioned "the pattern boundary of the aerial display is unclear", in the embodiment of FIGS. Therefore, the path of light is long and there are many interfaces through which the light passes. That is, in FIG. 2, the light emitted from the light emitting portion 4b travels along the path L1→path L2→path L3, the surface of the light guide plate 4 (surface on the display surface side), the back surface of the half mirror 6, and the surface of the light guide plate 4. and rear surface, the front surface (reflective surface) of the retroreflective sheet 5, the rear surface and front surface of the light guide plate 4, the rear surface and front surface of the half mirror 6, and the rear surface and front surface of the top cover 7. The long light path tends to cause light diffusion, and the large number of interfaces tends to cause light diffusion and attenuation, making the pattern boundary of the aerial display unclear. In this regard, in the embodiment of FIGS. 25 and 26, the light emitted from the light emitting portion 4b travels along the path L1→path L2→path L3, and passes through the surface of the light guide plate 4, the back surface of the half mirror 6, and the retroreflective sheet 5. Since the light passes through the front surface (reflecting surface), the rear surface and front surface of the half mirror 6, and the rear surface and front surface of the top cover 7, the path of the light is shortened and the interfaces through which it passes are reduced. As a result, the pattern boundary of the aerial display can be made clear.

Further, the above-mentioned "multiple images are visible" is caused mainly by the fact that the interface when passing through the light guide plate 4 on the paths L2 and L3 is visible in the embodiment of FIGS. 1 and 2 . In this regard, in the embodiments of FIGS. 25 and 26, the light exiting through the through holes 5a of the retroreflective sheet 5 on the path L1 does not pass through the interface of the light guide plate 4, so multiple images are visible. will be gone.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention.

As described above, the aerial display device according to the embodiment includes a retroreflective sheet, a transparent display device arranged on the retroreflective surface side of the retroreflective sheet, and a half mirror arranged on the light emitting surface side of the transparent display device. The transparent display device comprises a light guide plate having a light emitting part corresponding to a figure to be displayed in the air, and the light emitting part is a concave optical element having a V-shaped, polygonal, or top-flat arc-shaped cross section. consists of As a result, it is possible to easily adjust the light distribution to a desired one by adjusting the dimensions of each shape, and it is possible to improve the light efficiency, improve the brightness, and make the aerial display appropriate.

Further, a planar light emitter having a light emitting part, a retroreflective sheet disposed on the emission surface side of the planar light emitter and having a plurality of through holes representing a figure to be displayed in the air at a position corresponding to the light emitting part, a retroreflective sheet A half mirror is disposed on the light emitting surface side of the reflection sheet, and the light emitting section is composed of a concave optical element having a V-shaped, polygonal, or top-flat arc-shaped cross section. As a result, it is possible to easily adjust the light distribution to a desired one by adjusting the dimensions of each shape, and it is possible to improve the light efficiency, improve the brightness, and make the aerial display appropriate. In addition, it is possible to prevent the pattern boundaries of the mid-air display from being clear and the multiple images to be seen, thereby improving the quality of the mid-air display.

A retroreflective sheet, a transparent display device arranged on the retroreflective surface side of the retroreflective sheet, and a half mirror arranged on the light emitting surface side of the transparent display device, the transparent display device displays in the air. A light guide plate having a light emitting part corresponding to a figure and a linear light source facing the light incident side surface of the light guide plate are provided. It is composed of an optical element that is provided continuously or intermittently provided in the extending direction of the linear light source. As a result, it is possible to reduce the occurrence of dark areas caused by the linear optical element, improve the display quality, and optimize the aerial display.

Further, a light guide plate having a light emitting portion, a retroreflective sheet disposed on the light emitting surface side of the light guide plate and having a plurality of through holes representing a figure to be displayed in the air at a position corresponding to the light emitting portion, and an emission of the retroreflective sheet A half mirror arranged on the surface side and a linear light source facing the light incident side surface of the light guide plate are provided, and the light emitting part is provided continuously extending in a wave in the extending direction of the linear light source. Alternatively, it is composed of optical elements intermittently provided in the extending direction of the linear light source. As a result, it is possible to reduce the occurrence of dark areas caused by the linear optical element, improve the display quality, and optimize the aerial display. In addition, it is possible to prevent the pattern boundaries of the mid-air display from being clear and the multiple images to be seen, thereby improving the quality of the mid-air display.

Further, the optical elements intermittently provided in the extending direction of the linear light source are concave optical elements having a V-shaped, polygonal, or top-flat arc-shaped cross-section, and are approximately rugby ball-shaped when viewed from the exit surface side. Chopped into shapes or rectangles. As a result, the occurrence of dark areas can be further reduced, and the display quality can be further improved.

Moreover, the present invention is not limited by the above embodiments. 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, 3 linear light source, 4 light guide plate, 4b, 4b1, 4b2 light emitting portion, 4c optical element, 5 retroreflective sheet, 5a through hole, 6 half mirror, 7 top cover, 8 reflective sheet, EP eyepoint, I aerial display, 100 operation panel, F finger

Claims (5)

a retroreflective sheet;
a transparent display device disposed on the retroreflective surface side of the retroreflective sheet;
a half mirror arranged on the light emitting surface side of the transparent display device;
with
The transparent display device includes a light guide plate having a light-emitting portion corresponding to a figure to be displayed in the air, and the light-emitting portion is composed of a concave optical element having a V-shaped, polygonal, or top-flat arc-shaped cross section. to be
aerial display device. a planar light emitter having a light emitting portion;
a retroreflective sheet disposed on the emission surface side of the planar light emitter and having a plurality of through-holes representing a figure to be displayed in the air at positions corresponding to the light emitting portions;
a half mirror disposed on the exit surface side of the retroreflective sheet;
with
The light emitting unit is composed of a concave optical element having a V-shaped, polygonal, or top-flat arc-shaped cross section,
aerial display device. a retroreflective sheet;
a transparent display device disposed on the retroreflective surface side of the retroreflective sheet;
a half mirror arranged on the light emitting surface side of the transparent display device;
with
The transparent display device comprises a light guide plate having a light-emitting portion corresponding to a figure to be displayed in mid-air, and a linear light source facing the light incident side surface of the light guide plate,
The light emitting unit is provided to continuously extend in a wave in the extending direction of the linear light source, or is composed of an optical element intermittently provided in the extending direction of the linear light source.
aerial display device. a light guide plate having a light emitting portion;
a retroreflective sheet disposed on the light emitting surface side of the light guide plate and having a plurality of through holes representing a figure to be displayed in midair at positions corresponding to the light emitting portions;
a half mirror disposed on the exit surface side of the retroreflective sheet;
a linear light source facing the light incident side surface of the light guide plate;
with
The light emitting unit is provided to continuously extend in a wave in the extending direction of the linear light source, or is composed of an optical element intermittently provided in the extending direction of the linear light source.
aerial display device. The optical elements intermittently provided in the extending direction of the linear light source are concave optical elements having a V-shaped, polygonal, or top-flat arc-shaped cross section, and are approximately rugby ball-shaped when viewed from the exit surface side. or shredded into rectangles,
5. An aerial display device according to claim 3 or 4.

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