KR20220090157A - Table-top 3d display using dihedral corner reflector array and reflective polarizer film - Google Patents

Abstract

The present specification discloses a table-type 3D display having a reduced size compared to a conventional 3D display. Tabletop 3D display according to the present specification, a dihedral reflector; a reflective polarizing film attached to a lower surface of the dihedral reflector; input display; a first reflector disposed to reflect the light output from the input display toward a lower surface of the dihedral reflector; a linear polarizing film disposed between the input display and the first reflector; a second reflector disposed to be spaced apart a predetermined distance in a downward direction of the dihedral reflector; and a quarter wave plate attached to the upper surface of the second reflector.

Description

TABLE-TOP 3D DISPLAY USING DIHEDRAL CORNER REFLECTOR ARRAY AND REFLECTIVE POLARIZER FILM using a dihedral reflector and reflective polarizing film

The present invention relates to a tabletop 3D display, and more particularly, to a tabletop 3D display capable of reducing the overall size by using a dihedral reflector and a reflective polarizing film.

The content described in this section merely provides background information for the embodiments described herein and does not necessarily constitute prior art.

A table-top 3D display is a display that can provide a 3D image to a large number of users, and it has a table shape and refers to a display device used in places that require collaboration, such as a meeting. Unlike the conventional large-screen table-type display system using a large display panel or projector to provide only a two-dimensional image, the tabletop 3D display can provide a more realistic three-dimensional image to the user.

In order for this tabletop 3D display to provide a more realistic 3D image to the user, 1) different images according to the viewpoint (3D image), 2) high quality images, 3) large screen images, and 4) above a certain height It is necessary to provide a flotation video. In particular, in order to increase the levitation height of the image, there is a problem of spatial inefficiency as the device size increases together.

Therefore, there is a need for a tabletop 3D display that can efficiently use space while increasing the levitation height of the image.

Patent Publication No. 10-2009-0107501 (2009.10.13)

An object of the present specification is to provide a table-type 3D display having a reduced size compared to a conventional 3D display.

The present specification is not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

Tabletop 3D display according to the present specification for solving the above-described problems, a dihedral reflector; a reflective polarizing film attached to a lower surface of the dihedral reflector; input display; a first reflector disposed to reflect the light output from the input display toward a lower surface of the dihedral reflector; a linear polarizing film disposed between the input display and the first reflector; a second reflector disposed to be spaced apart a predetermined distance in a downward direction of the dihedral reflector; and a quarter wave plate attached to the upper surface of the second reflector.

According to an embodiment of the present specification, the input display may be disposed under the second reflector.

According to one embodiment of the present specification, the reflective polarizing film may have an optical property of reflecting light polarized through the linear polarizing film.

According to an embodiment of the present specification, the center of the dihedral reflector and the center of the second reflector may be located on a vertical line based on the height.

According to one embodiment of the present specification, the width of the second reflector may reflect all of the light emitted from the input display in correspondence to the optical path between the input display and the second reflector and the viewing angle of the input display. It can be width.

Other specific details of the invention are included in the detailed description and drawings.

According to the present specification, since the size is reduced compared to the conventional 3D display, it is suitable for manufacturing a table-type 3D display.

Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a block diagram schematically illustrating the configuration of a tabletop 3D display according to the present specification.
2 is a reference diagram for a light path of the tabletop display according to the present specification.
3 is a reference diagram for a structure of a dihedral reflector.
4 is a reference diagram for the principle of a levitation image of a dihedral reflector.
5 is a reference diagram for the angle of arrangement of the dihedral reflector and the input image.
6 is a reference diagram for a ghost image of a dihedral reflector.
7 is a reference diagram for a phenomenon in which a ghost image is displayed according to an arrangement position of an input display.
8 is a reference diagram for a phenomenon in which a ghost image is not seen according to an arrangement position of an input display.
9 is a reference view of a conventional 3D display using a dihedral reflector.
10 is a reference diagram for setting the arrangement positions of the first reflector, the second reflector, and the input display of the tabletop 3D display according to the present specification.
11 to 14 are reference views for calculating the arrangement positions of the first reflector, the second reflector, and the input display of the tabletop 3D display according to the present specification.

Advantages and features of the invention disclosed herein, and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present specification is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the present embodiments allow the disclosure of the present specification to be complete, and those of ordinary skill in the art to which this specification belongs. It is provided to fully inform those skilled in the art (hereinafter, 'those skilled in the art') the scope of the present specification, and the scope of the present specification is only defined by the scope of the claims.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the scope of the present specification. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, “comprises” and/or “comprising” does not exclude the presence or addition of one or more other components in addition to the stated components.

Like reference numerals refer to like elements throughout, and "and/or" includes each and every combination of one or more of the recited elements. Although "first", "second", etc. are used to describe various elements, these elements are not limited by these terms, of course. These terms are only used to distinguish one component from another. Accordingly, it goes without saying that the first component mentioned below may be the second component within the spirit of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used herein will have the meaning commonly understood by those of ordinary skill in the art to which this specification belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless specifically defined explicitly.

Spatially relative terms "below", "beneath", "lower", "above", "upper", etc. It can be used to easily describe the correlation between a component and other components. Spatially relative terms should be understood as terms including different directions of components during use or operation in addition to the directions shown in the drawings. For example, when a component shown in a drawing is turned over, a component described as "beneath" or "beneath" of another component may be placed "above" of the other component. can Accordingly, the exemplary term “below” may include both directions below and above. Components may also be oriented in other orientations, and thus spatially relative terms may be interpreted according to orientation. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram schematically illustrating the configuration of a tabletop 3D display according to the present specification.

Referring to FIG. 1 , the tabletop 3D display 100 according to the present specification includes a dihedral reflector 110 , a reflective polarizing film 111 , an input display 120 , a first reflector 130 , and a linearly polarizing film 121 . ), the second reflector 140 and the quarter wave plate 141 may be included. Meanwhile, in describing each configuration of the tabletop 3D display 100 according to the present specification, the directions shown in the drawings are referred to as up, down, left and right.

The dihedral corner reflector array (110) is an optical element that uses a double-sided symmetric imaging element to form an image of an object placed on the lower surface side of the element at a plane-symmetric position on the upper surface side of the element.

3 is a reference diagram for a structure of a dihedral reflector.

Referring to FIG. 3 , the dihedral reflector has a structure in which a front surface in which a reflective substrate is arranged in one direction and a rear surface in which a reflective substrate is arranged in a direction orthogonal to the one direction are combined. The structure of the dihedral reflector is described in <"Design of ghost-free floating 3D display with narrow thickness using offset lens and dihedral corner reflector arrays," Opt. It is described in more detail in Express　28, 15691-15705 (2020)>, so you can refer to it.

4 is a reference diagram for the principle of a levitation image of a dihedral reflector.

Referring to FIG. 4 , when light emitted from an object passes through a dihedral half-body, the light is reflected once each by two reflective substrates constituting the dihedral reflector. Then, the reflected light is imaged at a position symmetrical to the plane of the dihedral reflector. Accordingly, an image formed (real image) appears floating in the upper space of the dihedral reflector to the observer. The dihedral reflector is an optical device known to those skilled in the art, and the principle thereof is described in Korean Patent Application Laid-Open No. 10-2009-0107501, and detailed description thereof will be omitted.

The reflective polarizer film 111 may be attached to a lower surface of the dihedral reflector 110 . The reflective polarizing film 111 may serve to pass one of the two polarized light orthogonal to each other and reflect the other polarized light.

The input display 120 may output an image to be lifted. The input display 120 may provide a 2D image, and may provide a multi-view 3D image as a light field display. The type of the input display 120 can be variously selected by those skilled in the art, and is not limited to a specific type of display device. According to an exemplary embodiment of the present specification, the input display 120 may be disposed under the second reflector 140 .

The first reflector 130 may be disposed to reflect the light (image) output from the input display 120 toward the lower surface of the dihedral reflector 110 . The arrangement position of the first reflector 130 will be described later in more detail.

The linear polarizer film 121 may be disposed between the input display 120 and the first reflector 130 . Preferably, the linear polarization film 121 may be attached to the surface of the input display 120 . The linear polarization film 121 may modulate the light (image) output from the input display 120 to vibrate in only one specific direction.

The second reflector 140 may be disposed to be spaced apart from each other by a predetermined distance in the downward direction of the dihedral reflector 110 . The arrangement position of the second reflector 140 will be described later in more detail.

The quarter wave plate (Quarter Wave Plate, 141) serves to delay the incident light by a quarter wavelength. The quarter wave plate 141 may be attached to the upper surface of the second reflector 140 . Accordingly, when the light incident toward the second reflector 140 passes through the quarter wave plate 141 first, the quarter wave is delayed, and when reflected by the second reflector 140 , the light returns to the second reflector 140 . As it passes through the quarter-wave plate 141 again, the quarter-wave is delayed, so that the total half-wave is delayed.

2 is a reference diagram for a light path of the tabletop display according to the present specification.

Referring to FIG. 2 , light (image) emitted from the input display 120 may be polarized while passing through the linear polarization film 121 . In FIG. 2 , for convenience of explanation, light passing through the linearly polarized film 121 will be described as a vertically polarized example. The vertically polarized light is reflected from the first reflector 130 and is incident toward the lower surface of the dihedral reflector 110 . In this case, the reflective polarizing film 111 may have an optical characteristic of reflecting light polarized through the linear polarizing film 121 . In the example shown in FIG. 2 , the reflective polarizing film 111 may reflect vertical light and transmit horizontal light. Accordingly, the vertical light reflected from the first reflector 130 is reflected toward the second reflector 140 . The vertical light is delayed by half a wavelength by the quarter-wave plate 141 attached to the upper surface of the second reflector 140 . In this process, vertical light can be converted into horizontal light. The horizontal light reflected from the second reflector 140 is incident toward the lower surface of the dihedral reflector 110 . In this case, the reflective polarizing film 111 passes horizontal light, and finally the light (image) emitted from the input display 120 is formed on the upper surface of the dihedral reflector 110 .

Hereinafter, each configuration included in the tabletop 3D display 100 according to the present specification, in particular, the arrangement position and setting of the reflection angle of the first reflector 130 and the second reflector 140 will be described. To this end, the problems of the conventional 3D display using the dihedral reflector will be described first.

5 is a reference diagram for the angle of arrangement of the dihedral reflector and the input image.

Referring to (a) of FIG. 5 , when an input image is vertically arranged around a dihedral reflector (image plate), the observer observes that the input image and the floating image overlap visible phenomena occur. In order to solve this image overlap, a conventional 3D display using a dihedral reflector is shown in FIG. tilt and place However, even in this case, there is a problem in that a ghost image is generated.

6 is a reference diagram for a ghost image of a dihedral reflector.

Referring to FIG. 6A , the number of times an input image is reflected while passing through a dihedral reflector (image plate) is illustrated. Preferably, the input image is reflected an odd number of times in the process of passing through the dihedral reflector (image plate) to generate a floating image, and most preferably, it is reflected only once. However, depending on the distance and angle between the input image, the dihedral reflector, and the observer, even-numbered reflections may occur or may simply pass through. In this case, as shown in (b) of FIG. 6 , a problem in which a ghost image is observed in addition to a floating image may occur.

7 is a reference diagram for a phenomenon in which a ghost image is displayed according to an arrangement position of an input display.

Referring to FIG. 7 , when an input image is present in the central region of the dihedral reflector (refer to FIGS. 7 (a) and (c)), a ghost image is within the viewer's viewing angle. ) can be seen (see FIGS. 7 (b) and (d)).

8 is a reference diagram for a phenomenon in which a ghost image is not seen according to an arrangement position of an input display.

Referring to FIG. 7 , when an input image is present at a position deviating from the central region of the dihedral reflector (refer to FIGS. 8 (a) and (c)), the ghost image is within the viewer's viewing angle. It can be seen that (Ghost image) is not visible (see (b) and (d) of FIG. 8).

Meanwhile, the contents of FIGS. 7 and 8 are <"Design of ghost-free floating 3D display with narrow thickness using offset lens and dihedral corner reflector arrays," Opt. Express　28, 15691-15705 (2020)> is cited and can be referred to.

9 is a reference view of a conventional 3D display using a dihedral reflector.

FIG. 9A is a reference diagram for the relative position of the input display 12 in the 3D display 10 using the conventional dihedral reflector 11 for solving the ghost image problem described above. As can be seen from (a) of FIG. 9 , it can be seen that the input display 12 is disposed away from the central region of the dihedral reflector 11 and is spaced apart by a considerable distance. This is so that the input display 12 forms a predetermined angle from the center of the dihedral reflector 11 and at the same time exists outside the horizontal region of the dihedral reflector 11 . For this reason, the conventional 3D display 10 using a dihedral reflector necessarily requires a minimum vertical length and has been pointed out as a disadvantage in increasing the size of the entire device.

On the other hand, (b) of FIG. 9 is a tabletop 3D display 100 according to the present specification, which is shown to show that the vertical length is significantly reduced compared to the conventional 3D display 10 .

Next, an arrangement position and setting of a reflection angle of the first reflector 130 , the second reflector 140 , and the input display 120 will be described.

10 is a reference view for setting the arrangement positions of the first reflector, the second reflector, and the input display of the tabletop 3D display according to the present specification.

Referring to FIG. 10A , first, the dihedral reflector 110 and the input display 120 are disposed. In this case, the arrangement position of the dihedral reflector 110 and the input display 120 is a position where the ghost image described with reference to FIG. 8 is not generated. A second reflector 140 is disposed between the dihedral reflector 110 and the input display 120 . In this case, the center of the dihedral reflector 110 and the center of the second reflector 140 may be located on a vertical line based on the height. In addition, the width of the second reflector 140 corresponds to the distance (light path) between the input display 120 and the second reflector 140 and the viewing angle of the input display 120 to the input display ( 120) may have a width that can reflect all of the light emitted therefrom.

Referring to FIG. 10B , the input display 120 is symmetrically moved with respect to the reflective surface of the second reflector 140 . The dihedral reflector 110 is positioned between the optical path between the symmetrically moved input display 120 and the second reflector 140 .

Referring to FIG. 10C , the input display 120 symmetrically moved with respect to the second reflector 140 is symmetrically moved again with respect to the lower surface of the dihedral reflector 110 .

Referring to FIG. 10D , the first reflector 130 is disposed on the optical path between the input display 120 symmetrically moved twice and the dihedral reflector 110 . Then, the input display 120 symmetrically moved twice is symmetrically moved again with respect to the reflective surface of the first reflector 130 . The position of the input display 120 flipped three times corresponds to the final position in the tabletop 3D display 100 according to the present specification.

11 to 14 are reference views for calculating the arrangement positions of the first reflector, the second reflector, and the input display of the tabletop 3D display according to the present specification.

11 to 14, the center point, width, left and right positions and distances of each component on the ZX plane are set as coordinate values, so that each final position can be calculated. 11 to 14 are calculated based on a dihedral reflector having an arbitrary width and an input display having an arbitrary width, and the tabletop 3D display 100 according to the present specification is designed using optical elements of various sizes. can do.

As mentioned above, although the embodiments of the present specification have been described with reference to the accompanying drawings, those of ordinary skill in the art to which this specification belongs can realize that the present invention may be embodied in other specific forms without changing the technical spirit or essential features thereof. you will be able to understand Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

100 : Tabletop 3D Display
110: dihedral reflector
111: reflective polarizing film
120: input display
121: linear polarizing film
130: first reflector
140: second reflector
141: 1/4 wave plate

Claims (5)

dihedral reflector;
a reflective polarizing film attached to the lower surface of the dihedral reflector;
input display;
a first reflector disposed to reflect the light output from the input display toward a lower surface of the dihedral reflector;
a linear polarizing film disposed between the input display and the first reflector;
a second reflector disposed to be spaced apart a predetermined distance in a downward direction of the dihedral reflector; and
Tabletop 3D display comprising a; 1/4 wave plate attached to the upper surface of the second reflector. The method according to claim 1,
The input display is a tabletop 3D display, characterized in that disposed under the second reflector. The method according to claim 1,
The reflective polarizing film is a tabletop 3D display, characterized in that it has an optical property of reflecting the light polarized through the linear polarizing film. The method according to claim 1,
Tabletop 3D display, characterized in that the center of the dihedral reflector and the center of the second reflector are positioned on a vertical line based on the height. 5. The method according to claim 4,
The width of the second reflector is a width capable of reflecting all of the light emitted from the input display in correspondence to the optical path between the input display and the second reflector and the viewing angle of the input display. display.

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