Thin aerial image display device and non-contact input apparatus using same

Abstract

A non-contact input apparatus 10 comprises: (a) a thin aerial image display device 11 provided with an optical image formation means 18 which is formed in a flat plate shape having a light incidence surface 16 and a light emission surface 17 that are disposed parallel to each other, and in which a plurality of first light reflection surfaces and a plurality of second light reflection surfaces respectively formed at right angles to the light incidence surface 16 and the light emission surface 17 and disposed parallel to each other at predetermined intervals are disposed orthogonally in plan view, and a flat plate-shaped display 20 disposed on the light incidence surface 16 side of the optical image formation means 18 and having a light emitting surface 19 parallel to the light incidence surface 16, the thin aerial image display device displaying an aerial image 12 on an image formation plane 21 inclined at an angle α with respect to the light emission surface 17 on the light emission surface 17 side of the optical image formation means 18; and (b) a detection means 14 which is attached to the thin aerial image display device 11 and detects the position of an indication means 13 that is in contact with the aerial image 12.

Description

Thin aerial image display device and non-contact input device using the same

[0001] The present invention relates to a thin aerial image display device in which a plurality of first and second strip-shaped light-reflecting surfaces (mirror surfaces), each arranged parallel to one another at a predetermined interval, display an aerial image based on an image on a flat display arranged parallel to the light-entering surface of an aerial image forming means arranged orthogonally in a planar view, and a non-contact input device using the same.

[0002] For example, a stereoscopic imaging device (optical imaging device) described in Patent Document 1 is known as a device that uses light (scattered light) emitted from the object surface (target object) to form a stereoscopic image (aerial image = real image) of the object in the air. This imaging device has first and second light control panels formed inside two transparent flat plates, each of which has a number of strip-shaped metal reflective surfaces arranged at a constant pitch perpendicular to one side of the transparent flat plates. The first and second light control panels are closely attached to each other with their one sides facing each other so that their respective light reflective surfaces are orthogonal to each other. In this optical imaging device, as shown in Figures 3, 5, and 6 of Patent Document 1, an object image M' or N' formed in the air is generated at a position symmetrical to the object M or N across the optical imaging device. This also applies when a display device such as a monitor is installed instead of the object M or N and an aerial image of an image displayed on the display device is formed. Therefore, even in a non-contact input device that utilizes this optical imaging device, as shown in, for example, Figure 2 of Patent Document 2, the angle a between the display that displays the image and the optical imaging means is equal to the angle a between the optical imaging means and the spatial image that is imaged in space.

[0003] International Publication No. 2009 / 131128 Utility Model Registration No. 3219968

[0004] As described above, both the optical imaging device of Patent Document 1 and the non-contact input device of Patent Document 2 require a display device installed in an inclined position below the optical imaging device in order to tilt and form (float) an aerial image in the space above the optical imaging device based on an image displayed on the display device, thereby requiring a large installation space. As a result, the optical imaging device and the non-contact input device are large and lack installation flexibility, which has hindered the widespread use of optical imaging devices and non-contact input devices. In view of these circumstances, the present invention aims to provide a thin aerial image display device and a non-contact input device using the same that are thin yet capable of forming a clear aerial image, and that are space-saving and installable.

[0005] A thin aerial image display device according to a first aspect of the present invention that meets the above-mentioned objective is a thin aerial image display device formed in a flat plate shape having a light incident surface and a light exit surface that are arranged in parallel, the thin aerial image display device having a plurality of first light reflecting surfaces that are formed perpendicular to the light incident surface and arranged in parallel at a predetermined interval, and a plurality of second light reflecting surfaces that are formed perpendicular to the light exit surface and arranged in parallel at a predetermined interval, the thin aerial image display device comprising an optical imaging means in which the first light reflecting surfaces and the second light reflecting surfaces are arranged orthogonal to each other in a planar view, and an imaging surface that is inclined at an angle α with respect to the light exit surface on the light exit surface side, When an image display means having a display surface that displays an image at a position symmetrical to the imaging surface across from the optical imaging means is virtually positioned on the front light surface side of the optical imaging means, light irradiated from the display surface toward the front light surface of the optical imaging means is reproduced on a flat display that is positioned on the front light surface side of the optical imaging means and has an emitting surface parallel to the light entrance surface, and an aerial image corresponding to the image is formed on the imaging surface by light that is irradiated from the emitting surface toward the front light surface of the optical imaging means and is reflected once by the first light reflecting surface and then once by the second light reflecting surface.

[0006] In the thin aerial image display device according to the first invention, the light-emitting surface of the flat display is preferably made up of a plurality of light-emitting elements arranged in a grid pattern.

[0007] In the thin aerial image display device according to the first invention, it is preferable that the central axis of the light emitted from each of the light-emitting elements is perpendicular to the display surface of the image display means.

[0008] In the thin aerial image display device according to the first invention, it is preferable that the directivity angle of light emitted from each of the light emitting elements is within 40 degrees.

[0009] In the thin aerial image display device according to the first invention, the light-emitting elements are preferably micro LEDs.

[0010] A non-contact input device according to a second aspect of the present invention, which is in line with the above-mentioned object, is a non-contact input device that uses the thin aerial image display device according to the first aspect of the present invention, and comprises the thin aerial image display device and a detection means attached to the thin aerial image display device for detecting the position of an instruction means that touches the aerial image.

[0011] In the non-contact input device according to the second aspect of the present invention, it is preferable that the detection means be disposed parallel to a lower side of the aerial image.

[0012] In the non-contact input device of the second invention, it is preferable that the detection means has an emitting unit that irradiates detection light in a direction parallel to the aerial image to form a detection surface parallel to the aerial image, and a light receiving unit that receives reflected light reflected from the pointing means when the pointing means touches the detection surface at a position that overlaps the aerial image when viewed from the front.

[0013] The thin aerial image display device of the first invention can have an imaging surface inclined at an angle α with respect to the light exit surface on the light exit surface side of the optical imaging means, based on light irradiated toward the light entrance surface from a flat display having an light emitting surface parallel to the light entrance surface of the optical imaging means, and is extremely compact and has excellent installation flexibility.

[0014] In the thin aerial image display device according to the first aspect of the present invention, when the light-emitting surface of the flat display is composed of a plurality of light-emitting elements arranged in a grid pattern, a high-quality, clear aerial image can be displayed.

[0015] In the thin aerial image display device of the first invention, when the central axis of the light emitted from each light-emitting element is perpendicular to the display surface of the image display means, the image displayed on the virtual image display means can be accurately reproduced on a flat display, and the aerial image can be reliably displayed on a predetermined imaging surface.

[0016] In the thin aerial image display device according to the first invention, when the directivity angle of the light emitted from each light-emitting element is within 40 degrees, a bright and clear aerial image can be obtained.

[0017] In the thin aerial image display device according to the first invention, when the light emitting elements are micro LEDs, a high-definition aerial image can be obtained, and the device has a long life and excellent energy saving properties.

[0018] The non-contact input device of the second invention is extremely thin, space-saving, and easy to install, by using a thin aerial image display device equipped with a flat display having an emitting surface parallel to the light entrance surface of the optical imaging means.

[0019] In the non-contact input device of the second invention, when the detection means is arranged parallel to the lower edge of the aerial image, the thin aerial image display device and the detection means can be integrated to simplify the configuration, resulting in excellent space-saving and mass-producible properties.

[0020] In the non-contact input device of the second invention, when the detection means has an emitting unit that irradiates detection light in a direction parallel to the aerial image to form a detection surface parallel to the aerial image, and a light receiving unit that receives reflected light from the pointing means when the pointing means touches the detection surface at a position that overlaps with the aerial image when viewed from the front, there is no need to install a separate emitting unit externally for irradiating detection light, thereby improving space saving and installation flexibility.

[0021] Fig. 1 is a perspective view showing a non-contact input device using a thin aerial image display device according to an embodiment of the present invention; Fig. 2 is a sectional side view of a main part showing the non-contact input device; (A) and (B) are a sectional front view and a sectional side view showing the operation of an optical imaging means in the thin aerial image display device used in the non-contact input device; and Fig. 3 is a schematic side view illustrating image display by a flat panel display of the non-contact input device.

[0022] A non-contact input device using a thin aerial image display device according to one embodiment of the present invention will be described with reference to the drawings. As shown in Figures 1 and 2, the non-contact input device 10 according to the embodiment of the present invention comprises a thin aerial image display device 11 and a detection means 14 attached to the thin aerial image display device 11 for detecting the position of a pointing means 13 (here, a finger) such as a finger or a touch pen that touches an aerial image 12.

[0023] As shown in Figure 2, the thin aerial image display device 11 includes a flat-plate-shaped optical imaging means 18 having a parallel-arranged light incident surface 16 and a light exit surface 17, and a flat display 20 arranged on the light incident surface 16 side of the optical imaging means 18 and having a light-emitting surface 19 parallel to the light incident surface 16. The aerial image 12 is displayed on an imaging surface 21 tilted at an angle α with respect to the light exit surface 17 on the light exit surface 17 side. Here, the angle α is preferably in the range of approximately 30 to 60 degrees, but is not limited to this range and can be selected appropriately. As shown in Figures 3(A) and 3(B), the optical imaging means 18 includes a plurality of first light-reflecting surfaces 22 formed perpendicular to the light incident surface 16 and arranged parallel to each other at a predetermined interval, and a plurality of second light-reflecting surfaces 23 formed perpendicular to the light exit surface 17 and arranged parallel to each other at a predetermined interval, with the first light-reflecting surfaces 22 and the second light-reflecting surfaces 23 arranged orthogonally in a plan view.

[0024] In manufacturing this optical imaging means 18, for example, a transparent resin is molded (for example, by injection molding, press molding, roll molding, etc.) to produce a first molded body 27 having on one side (here the upper side) a plurality of grooves 26 with a trapezoidal cross section that expands toward one side, with one side being a vertical surface 24 and the other side being an inclined surface 25, and arranged in parallel at predetermined intervals, and a second molded body 31 having on the other side (here the lower side) a plurality of grooves 30 with a trapezoidal cross section that expands toward the other side, with one side being a vertical surface 28 and the other side being an inclined surface 29, and arranged in parallel at predetermined intervals, as shown in Figures 3(A) and (B). Then, the vertical surfaces 24, 28 of the grooves 26, 30 of the first molded body 27 and the second molded body 31 are covered with a metal reflective film 33, thereby forming a first light control section 35 having a plurality of first light reflective surfaces 22 and a second light control section 36 having a plurality of second light reflective surfaces 23. The metal reflective film 33 specularly reflects light (specular reflection), and is made of a metal such as aluminum, and can cover the vertical surfaces 24, 28 by a method such as sputtering, metal vapor deposition, spraying of metal microparticles, ion beam irradiation, or plating. Then, each groove 26 of the first light control unit 35 and each groove 30 of the second light control unit 36 ​​are filled with transparent adhesive 37, and with the grooves 26 and 30 facing each other, the first light control unit 35 and the second light control unit 36 ​​are stacked (overlapped) in the thickness direction, joined, and integrated so that the first light reflecting surface 22 and the second light reflecting surface 23 are perpendicular in a planar view, thereby obtaining the optical imaging means 18.

[0025] Next, the operation of the optical imaging means 18 will be described. As shown in FIGS. 3(A) and 3(B), in the optical imaging means 18, among the light emitted from an object (not shown) and incident on the first light control unit 35 from the incident light surface 16, for example, light L1 and L2 are incident on the first light control unit 35 from positions P11 and P21 respectively, are reflected once at positions P12 and P22 on the first light reflecting surface 22, enter the second light control unit 36, are reflected once at positions P13 and P23 on the second light reflecting surface 23, and are emitted into the air from the second light control unit 36 at positions P14 and P24 on the light emitting surface 17. Here, light L1 and L2 are incident on the transparent adhesive 37 from the first molded body 27 at Q1 and Q2 in FIG. 3(B), and are incident on the second molded body 31 from the transparent adhesive 37 at S1 and S2 in FIG. 3(A). However, since the refractive indices η1 and η2 of the first molded body 27 and the second molded body 31 are the same and approximate (substantially equal) to the refractive index η3 of the transparent adhesive 37, the influence of refraction is extremely small, and phenomena such as total reflection and spectroscopy do not occur. Therefore, an infinite number of lights emitted from the object, reflected once by the first light reflecting surface 22 of the optical imaging means 18, and subsequently reflected once by the second light reflecting surface 23 form an image in the air, and an aerial image (not shown) that is a real image of the object is formed at a position symmetric to the object with the optical imaging means 18 interposed therebetween.

[0026] In addition, although light L1 and L2 are refracted at positions P11 and P21 on the incident light surface 16 and positions P14 and P24 on the light emitting surface 17 respectively, the transparent resin (the first molded body 27 and the second molded body 31) that serves as the base material of the first light control unit 35 and the second light control unit 36 has the same refractive index and is homogeneous. All the light involved in the formation of the aerial image is refracted at a constant (same) angle at the incident light surface 16 and the light emitting surface 17 in the same manner as light L1 and L2 regardless of the incident position and the emission position. Therefore, these refractions do not affect the image formation. Also, in FIGS. 3(A) and 3(B), the left side surface of the metal reflection film 33 serves as the first light reflecting surface 22 and the second light reflecting surface 23. However, the metal reflection film 33 can function as the first light reflecting surface and the second light reflecting surface on either the front or back (left or right in FIGS. 3(A) and 3(B)) surface. Depending on the arrangement of the first light control unit 35 and the second light control unit 36 (inversion of front and back) or the incident direction of the light, either the front or back surface of the metal reflection film 33 functions as the first light reflecting surface and the second light reflecting surface.

[0027] In a conventional aerial image display device that combines an indicator such as a display with the optical imaging means 18, and in a non-contact input device that uses the aerial image display device, in order to tilt and form (float) the aerial image in the space above the optical imaging means 18, the display must be installed in an inclined state below the optical imaging means 18, which increases the height (thickness) of the aerial image display device and the non-contact input device, resulting in problems such as a lack of flexibility in installation and ease of handling. In contrast, in the thin aerial image display device 11 shown in Figures 1 and 2, when an image display means 40 having a display surface 39 that displays an image at a position symmetrical to the image surface 21 across the optical imaging means 18 (the position of the display of a conventional aerial image display device) is virtually placed on the light entrance surface 16 side of the optical imaging means 18, the light irradiated from the display surface 39 toward the light entrance surface 16 of the optical imaging means 18 is reproduced on a flat display 20 that is placed on the light entrance surface 16 side of the optical imaging means 18 and has a light-emitting surface 19 parallel to the light entrance surface 16. 4, the flat display 20 can reproduce the image to be displayed on the display surface 39 by irradiating, from the light-emitting surface 19, each light contained in a bundle of light irradiated from a plurality of pixels 41 (four pixels are shown here as a representative) constituting an image to be displayed on the display surface 39 of the virtually arranged image display means 40 toward the light-receiving surface 16 of the optical imaging means 18, and virtually concentrating the light from each pixel 41. In other words, the image to be displayed on the display surface 39 of the image display means 40 can be projected onto the light-emitting surface 19 of the flat display 20, and the image projected on the light-emitting surface 19 can be reconstructed and displayed by a plurality of light-emitting elements (not shown) arranged on the light-emitting surface 19.

[0028] In FIG. 2 , the light-emitting surface 19 of the flat display 20 is composed of a plurality of light-emitting elements 42 arranged in a grid pattern (vertical and horizontal). Micro-LEDs are preferably used as the light-emitting elements 42, but this is not limiting. Light-emitting elements that display a color image by combining three colors of light (R, G, and B) can also be used as appropriate. The central axis of light emitted from each light-emitting element 42 (the light ray indicated by the arrow in FIG. 2 ) is perpendicular to the display surface 39 of the image display unit 40, so the angle θ between the central axis of the light emitted from each light-emitting element 42 and the light-emitting surface 19 is 90°-α. The directivity angle of the light emitted from each light-emitting element 42 is preferably within 40°, but is not limited thereto and can be selected as appropriate. In this way, instead of the conventional image display unit 40 that is tilted at an angle α on the light-receiving surface 16 side of the optical imaging unit 18, the flat display 20 is arranged parallel to the light-receiving surface 16, thereby obtaining a thin aerial image display device 11. The thin aerial image display device 11 can form an aerial image 12 corresponding to the image on the image display means 40 on the imaging surface 21 by using light that is irradiated from the light-emitting surface 19 toward the light-entering surface 16 of the optical imaging means 18, reflected once by the first light-reflecting surface 22 (see Figure 3 (B)) and then reflected once by the second light-reflecting surface 23 (see Figure 3 (A)).

[0029] Next, the detection unit 14 will be described. As shown in Figures 1 and 2, the detection unit 14 is disposed inside the housing 43 of the thin aerial image display device 11 and parallel to the bottom edge of the aerial image 12. An opening 44 parallel to the longitudinal direction of the detection unit 14 is formed in the top surface of the housing 43. The detection unit 14 has a light-emitting unit (not shown) that irradiates detection light through the opening 44 in a direction parallel to the aerial image 12 to form a detection surface 45 parallel to the aerial image 12 (in this embodiment, coincident with the imaging surface 21), and a light-receiving unit (not shown) that receives reflected light from the pointing unit 13 when the pointing unit 13 touches the detection surface 45 at a position overlapping the aerial image 12 in a front view. With the above configuration, the aerial image 12 (= imaging surface 21, detection surface 45) can function as a non-contact input screen, and when a user looks at the aerial image 12 and indicates a specific position on the aerial image 12 with the indicating means 13, that position is detected by the detecting means 14, and text is input or a specific operation (command) is executed corresponding to the indicated position.

[0030] The detection unit 14 is preferably a flat bar-shaped (strip-shaped) optical sensor such as a zForce® AIR touch sensor or AIRBAR®. The position of the pointing unit 13 pointing at the aerial image 12 can be detected by scanning the surface of the aerial image 12 (imaging plane 21) with detection light, such as laser light or infrared light, emitted from the detection unit 14 (light-emitting unit). While the detection unit 14 is housed inside the housing 43 in this embodiment, the detection unit 14 may be installed on the exterior top surface of the housing 43, thereby omitting the opening 44. The detection unit 14 may also be disposed parallel to the aerial image 12, on either the left or right side of the aerial image 12. In this case, the detection unit 14 is rotatably held in the housing 43 and placed on the top surface of the housing 43 when not in use, thereby achieving excellent compactness. The configuration of the detection unit is not limited to that of this embodiment, and any configuration capable of detecting the position of the pointing unit 13 touching the aerial image 12 is sufficient. For example, the detection means may be a frame-type sensor (a type of optical proximity sensor) formed in a frame shape along the outer periphery of the aerial image 12 and having a plurality of light-emitting elements and light-receiving elements arranged around the aerial image 12, or an infrared motion sensor, etc. Note that in this embodiment, the imaging surface 21 and the detection surface 45 coincide with each other, but the detection surface 45 may be arranged parallel to the imaging surface 21 with a gap in front of or behind the imaging surface 21.

[0031] Although the present invention has been described above by way of example, it is not limited to the configurations described in the above examples and includes other embodiments and modifications conceivable within the scope of the claims. As a method for integrating the first light control unit and the second light control unit, the first light control unit and the second light control unit may be arranged facing each other so that one side of the first light control unit faces the other side of the second light control unit, i.e., the sides on which the grooves are formed, and a sheet-like transparent resin having a lower melting point than the first molded body and the second molded body is sandwiched between them, and the materials are heated and pressurized in a vacuum to melt and solidify only the transparent resin. Alternatively, the grooves of the first light control unit and the second light control unit may be filled separately with molten transparent resin, which is solidified and molded into a flat plate shape and then joined with a transparent adhesive or the like. In this case, instead of one surface of the first light control unit and the other surface of the second light control unit being arranged opposite each other and joined together, one surface of the first light control unit and one surface of the second light control unit may be arranged opposite each other and joined together, or the other surface of the first light control unit and one surface of the second light control unit may be arranged opposite each other and joined together. Furthermore, instead of the first and second light control units being formed separately from two transparent resin molded bodies and then joined together, the first and second light control units may be formed on both surfaces of a single transparent resin molded body.

[0032] Furthermore, in the above-described embodiments, the optical imaging means is described as having the first and second light control units each having a plurality of light reflecting surfaces arranged linearly (parallel). However, a first light control unit having a plurality of light reflecting surfaces arranged radially and a second light control unit having a plurality of light reflecting surfaces arranged concentrically may also be used. In this case, the radial light reflecting surfaces of the first light control unit are arranged linearly around a reference point X, while the concentric light reflecting surfaces of the second light control unit are curved along concentric circles centered around a reference point Y that overlaps with the reference point X in a planar view. However, the two light reflecting surfaces intersect at right angles in a planar view. Therefore, an aerial image can be formed similarly to the above-described embodiments. Furthermore, as described in Japanese Patent No. 5,437,436, for example, the optical imaging means may be a first and second light control unit each having a plurality of strip-shaped reflecting surfaces arranged perpendicularly (e.g., at the same pitch) on one side of the optical imaging means, which are overlapped so that the strip-shaped reflecting surfaces intersect at right angles in a planar view. In the above embodiment, the grooves of the first and second molded bodies (first and second light control units) are formed to have a trapezoidal cross section, but since the bottom surface of the groove is not an essential component of the optical imaging means, the dimensions (width) of the bottom surface do not need to be strictly controlled, and the groove may be formed to have a triangular cross section that widens to one side or the other, with one side being a vertical surface and the other side being an inclined surface.

[0033] The thin aerial image display device of the present invention and the non-contact input device using it are thinner than conventional aerial image display devices and non-contact input devices, yet can form clear aerial images, and are excellent in space-saving and installation flexibility, making it possible to install them in places where installation was previously difficult, promoting the replacement of contact input devices with non-contact input devices and promoting the spread of non-contact input devices.

[0034] 10: Non-contact input device, 11: Thin aerial image display device, 12: Aerial image, 13: Pointing means, 14: Detection means, 16: Light incident surface, 17: Light exit surface, 18: Optical imaging means, 19: Light emitting surface, 20: Flat display, 21: Imaging surface, 22: First light reflecting surface, 23: Second light reflecting surface, 24: Vertical surface, 25: Inclined surface, 26: Groove, 27: First molded body, 28: Vertical surface, 29: Inclined surface, 30: Groove, 31: Second molded body, 33: Metal reflective film, 35: First light control unit, 36: Second light control unit, 37: Transparent adhesive, 39: Display surface, 40: Image display means, 41: Pixel, 42: Light emitting element, 43: Housing, 44: Opening, 45: Detection surface

Claims

1. A thin aerial image display device formed in a flat plate shape having parallel arranged light entrance and exit surfaces, having a plurality of first light reflecting surfaces formed perpendicular to the light entrance surface and arranged in parallel at a predetermined interval, and a plurality of second light reflecting surfaces formed perpendicular to the light exit surface and arranged in parallel at a predetermined interval, the first light reflecting surfaces and the second light reflecting surfaces being arranged perpendicular to each other in a planar view, the device comprising an optical imaging means having an imaging surface inclined at an angle α to the light exit surface on the light exit surface side, A thin aerial image display device characterized in that, when an image display means having a display surface that displays an image at a position symmetrical to the imaging surface of the optical imaging means is virtually positioned on the imaging surface side of the optical imaging means, light irradiated from the display surface toward the imaging surface of the optical imaging means is reproduced on a flat display arranged on the imaging surface side of the optical imaging means and having a light emitting surface parallel to the light entrance surface, and an aerial image corresponding to the image is formed on the imaging surface by light irradiated from the light emitting surface toward the imaging surface of the optical imaging means, which is reflected once by the first light reflecting surface and then once by the second light reflecting surface.

2. A thin aerial image display device according to claim 1, characterized in that the light-emitting surface of the flat display is composed of a plurality of light-emitting elements arranged in a lattice pattern.

3. A thin aerial image display device according to claim 2, characterized in that the central axis of the light emitted from each of said light-emitting elements is perpendicular to said display surface of said image display means.

4. A thin aerial image display device according to claim 2, characterized in that the directivity angle of the light emitted from each of said light emitting elements is within 40 degrees.

5. A thin aerial image display device according to claim 2, characterized in that the light emitting element is a micro LED.

6. A non-contact input device using a thin aerial image display device according to any one of claims 1 to 5, comprising: said thin aerial image display device; and a detection means attached to said thin aerial image display device for detecting the position of a pointing means that touches said aerial image.

7. A non-contact input device according to claim 6, wherein said detection means is disposed parallel to the lower side of said aerial image.

8. A non-contact input device as described in claim 7, characterized in that the detection means has a light-emitting unit which irradiates detection light in a direction parallel to the aerial image to form a detection surface parallel to the aerial image, and a light-receiving unit which receives reflected light from the pointing means when the pointing means touches the detection surface at a position overlapping the aerial image when viewed from the front.

Images