JP7572516B1 - Floating Projection Device - Google Patents

Abstract

The floating projection device includes a mirror structure, an optical structure, an optical coating, and a display. The optical structure covers the mirror structure and forms a receiving space between the mirror structure and the optical coating. The optical coating is disposed on the optical structure. The display is disposed in the receiving space formed between the optical structure and the mirror structure and is used to transmit a plurality of image beams toward the optical structure.
[Effect] A floating projection device capable of effectively improving the display effect is provided.
[Selection diagram] Figure 1

Description

The present invention relates to a floating projection device, and in particular to a floating projection device that can improve the display effect.

In the prior art, a floating projection device has two concave mirror structures superimposed on each other, with an opening formed in the center of the upper mirror structure. A real object is placed in the floating projection device. An image of the real object undergoes multiple reflections within the floating projection device, passes through the opening in the center of the upper mirror structure, and forms a display image that is close to the real object above the floating projection device.

In the floating projection device of the above-mentioned prior art, the viewing angle of the generated display image is somewhat limited. Furthermore, when a user views the display image from above, the actual object inside the floating projection device can be easily observed at the same time through the opening, resulting in a phenomenon of visual interference.

The present invention provides a floating projection device that can effectively improve the display effect.

The floating projection device of the present invention includes a mirror structure, an optical structure, an optical coating, and a display. The optical structure covers the mirror structure and forms a receiving space between the mirror structure and the optical coating. The optical coating is disposed on the optical structure. The display is installed in the receiving space formed between the optical structure and the mirror structure and is used to transmit a plurality of image beams toward the optical structure.

Based on the above, the floating projection device of the present invention installs an optical coating on the upper optical structure. The optical coating can reflect or pass the image beam according to the polarization direction of the beam, and form a display image above the floating projection device. In this way, the viewing angle of the display image generated by the floating projection device can be greatly improved, and the quality of the display image can be effectively improved.

1 is a schematic diagram of a floating projection device according to an embodiment of the present invention; FIG. 2 is a schematic diagram of an imaging method of a floating projection device according to an embodiment of the present invention; FIG. 2 is a schematic diagram of image beam progression details of a floating projection device according to one embodiment of the present invention; FIG. 2 is a schematic diagram of an imaging distance of a floating projection device according to an embodiment of the present invention. 1 is a schematic diagram of a floating projection device according to an embodiment of the present invention; FIG. 5B is a schematic diagram of the travel path of an image beam through the floating projection device 500 of FIG. 5A. 1 is a schematic diagram of a floating projection device according to an embodiment of the present invention; FIG. 6B is a schematic diagram of the travel path of an image beam through the floating projection device 600 of FIG. 6A.

Referring to FIG. 1, FIG. 1 is a schematic diagram of a floating projection device according to an embodiment of the present invention. The floating projection device 100 includes a mirror structure 110, an optical structure 120, an optical coating 130, and a display 140. In this embodiment, the optical structure 120 is installed above the mirror structure 110. Here, the optical structure 120 covers the mirror structure 110 and forms a receiving space Z1 between the mirror structure 110. The optical coating 130 is installed on the optical structure 120. Here, the optical coating 130 is installed on the inner surface SI of the optical structure 120 facing the mirror structure 110. The display 140 is installed in the receiving space Z1. The display 140 is used to transmit a plurality of image beams IMB toward the optical structure 120.

In this embodiment, the optical coating 130 comprises a retardation film layer and a polarization selective reflection film layer, where the polarization selective reflection film layer is disposed between the retardation film layer and the inner surface SI of the mirror structure 110. The retardation film layer can change the polarization form of the received beam, and the polarization selective reflection film layer is arranged to select whether to reflect or pass the received beam depending on the polarization form of the received beam.

In this embodiment, the image beam IMB transmitted by the display 140 can undergo multiple reflections and one pass in the mirror structure 110 and the optical coating 130, and can form a real display image on an image plane IMP close to the outer surface SO of the optical structure 120 outside the accommodation space Z1 formed between the mirror structure 110 and the optical structure 120.

The above imaging method allows the creation of a display image that resembles a real object that can be viewed from a variety of angles, which can be called a hologram.

In this embodiment, the optical structure 120 may be a transparent structure. In this embodiment, the mirror structure 110 and the optical structure 120 may both be concave structures, and the concave surface of the mirror structure 110 and the concave surface of the optical structure 120 may face each other. The mirror structure 110 and the optical structure 120 may have a first radius of curvature and a second radius of curvature, respectively, where the first radius of curvature and the second radius of curvature are non-zero real numbers. In addition, the display 140 may be a liquid crystal display.

Regarding the travel path of the beam in the embodiment of the present invention, reference can be made to FIG. 2, which shows a schematic diagram of the imaging method of the floating projection device in the embodiment of the present invention. In FIG. 2, the display 140 can transmit image beams IMB1 and IMB2 toward the optical coating 130. The optical coating 130 can reflect the image beams IMB1 and IMB2, respectively, to generate reflected beams RB11 and RB21. The reflected beams RB11 and RB21 proceed toward the mirror structure 110. The mirror structure 110 is also used to reflect the reflected beams RB11 and RB21 to generate reflected beams RB12 and RB22, respectively.

The reflected beams RB12 and RB22 can then pass through the optical coating 130 and the optical structure 120 to generate a display image outside the containment space Z1.

For further explanation, please refer to the detailed schematic diagram of the image beam progression of the floating projection device of the embodiment of the present invention shown in FIG. 3. In this embodiment, the image beam IMB generated by the display is circularly polarized light having a first rotation, for example, the first rotation is right-handed. When the image beam IMB is sent to the retarder film layer QWP, the retarder film layer QWP can change the image beam IMB to a linearly polarized light in a first direction, for example, the first direction is vertical. In this embodiment, the retarder film layer QWP can be a quarter retarder.

The polarization selective reflection film layer IQPS can then receive the vertically linearly polarized image beam IMB and selectively reflect the image beam IMB to generate a reflected beam RB1. The reflected beam RB1 passes through the retardation film layer QWP, which can convert the reflected beam RB1 into right-handed circularly polarized light.

The reflected beam RB1 of right-handed circular polarization can be sent to the reflecting surface of the mirror structure 310. The mirror structure 310 is used to reflect the reflected beam RB1 and generate a reflected beam RB2, where the reflected beam RB2 is circularly polarized with a second rotatory power (left-handed). The reflected beam RB2 then passes through the retardation film layer QWP, which can convert the reflected beam RB2 into linearly polarized light in a second direction, which is, for example, horizontal.

The reflected beam RB2, which is horizontally linearly polarized, can be sent to the polarization selective reflection film layer IQPS. The polarization selective reflection film layer IQPS can then pass through the reflected beam RB2 and image the reflected beam RB2 onto an image plane IMP to form a display image.

For calculating the imaging distance of the floating projection device in the embodiment of the present invention, please refer to FIG. 4, which shows a schematic diagram of the imaging distance of the floating projection device in the embodiment of the present invention. In this embodiment, the mirror structure 410 and the optical structure 420 of the floating projection device 400 are both concave structures, and have radii of curvature R2 and R1, respectively. The vertical distance between the mirror structure 410 and the image plane IMP is L (image distance), and the vertical distance between the mirror structure 410 and the optical coating 430 is A.

Equation 1

Based on Equation 1, the following Relation Equation 1 is obtained. In the equation, A is positive, R1 is negative, and R2 is positive.

Equation 2

where I1 is the image distance of the primary image and FR1 is the focal length of optical structure 420.

From relation 1, the image distance in primary imaging can be calculated as follows:

Equation 3

Then, based on the image distance I1 of the primary image, the image distance of the secondary image can be further calculated.

Equation 4

ここで、浮遊投影の要求によれば、像距離Ｌは距離Ａよりも大きい必要がある。したがって、設計においては、適当な曲率半径Ｒ２を有するミラー構造４１０及び曲率半径Ｒ１を有する光学構造４２０を選択することができ、浮遊投影装置４００は、表示画像をホログラム画像として効果的に生成することができる。

Here, according to the requirements of floating projection, the image distance L needs to be greater than the distance A. Therefore, in the design, the mirror structure 410 with a suitable curvature radius R2 and the optical structure 420 with a suitable curvature radius R1 can be selected, and the floating projection device 400 can effectively generate the display image as a hologram image.

5A and 5B, FIG. 5A is a schematic diagram of a floating projection device according to one embodiment of the present invention, and FIG. 5B is a schematic diagram of the traveling path of an image beam of the floating projection device 500 of FIG. 5A. In FIG. 5A, the floating projection device 500 includes a mirror structure 510, an optical structure 520, an optical coating 530, and a display 540. Different from the embodiment of FIG. 1, in this embodiment, the mirror structure 510 may be a planar structure, and the optical structure 520 and the optical coating 530 may be concave structures, and the concave surface formed by the optical structure 520 and the optical coating 530 faces the reflective surface of the mirror structure 510.

In FIG. 5B, the image beam generated by the display 540 can undergo multiple reflections and a single pass between the optical coating 530 and the mirror structure 510 to form a display image on the image plane IMP. In this embodiment, the optical coating 530 of the floating projection device 500 has a radius of curvature R1. The vertical distance between the mirror structure 510 and the image plane IMP is L (image distance), and the vertical distance between the mirror structure 510 and the optical coating 530 is A. Based on the above formula 1, the relationship 2 can be obtained.

Equation 5

式中、Ｉ１は一次結像の像距離であり、ＦＲ１は光学コーティング５３０の焦点距離である。さらに、次の通り導出することができる。

where I1 is the image distance of the primary image and FR1 is the focal length of the optical coating 530. Furthermore, it can be derived as follows:

Equation 6

このとき、Ａは正であり、Ｒ１は負である。

In this case, A is positive and R1 is negative.

From the above derivation, it can be seen that the imaging distance of the optical coating 530 is equal to AP. In order to meet the requirement of floating the display image, the imaging of the optical coating 530 can be generated above the optical structure 520 through the reflecting action of the mirror structure 510. Therefore, the imaging distance of the optical coating 530 needs to be greater than 2A. In addition, since the display image generated by the present invention is a real image, the distance A needs to be greater than half the radius of curvature R1. By combining the above elements, the relational equation 3 can be derived.

Equation 7

In other words, by selecting a radius of curvature R1 of the optical coating 530 that satisfies the above relationship, the floating projection device 500 can effectively generate a display image as a hologram image.

6A and 6B, FIG. 6A shows a schematic diagram of a floating projection device according to one embodiment of the present invention, and FIG. 6B shows a schematic diagram of the traveling path of an image beam in the floating projection device 600 of FIG. 6A. In FIG. 6A, the floating projection device 600 includes a mirror structure 610, an optical structure 620, an optical coating 630, and a display 640. Different from the embodiment of FIG. 1, in this embodiment, the mirror structure 610 may be a concave structure, the optical structure 620 and the optical coating 630 may be planar structures, and the concave surface formed by the mirror structure 610 may face the optical structure 620 and the optical coating 630.

In FIG. 6B, the image beam generated by the display 640 can undergo multiple reflections and a single pass between the optical coating 630 and the mirror structure 610 to form a display image on the image plane IMP. In this embodiment, the mirror structure 610 of the floating projection device 600 has a radius of curvature R2. The vertical distance between the mirror structure 610 and the image plane IMP is L (image distance), and the vertical distance between the mirror structure 610 and the optical coating 630 is A. Based on the above formula 1, the relationship 4 can be obtained.

Equation 8

式中、Ｉ１は一次結像の像距離であり、ＦＲ２はミラー構造６１０の焦点距離である。さらに、次の通り導出することができる。

where I1 is the image distance of the primary image and FR2 is the focal length of the mirror structure 610. Furthermore, it can be derived as follows:

Equation 9

このとき、Ａは負であり、Ｒ２は正である。

In this case, A is negative and R2 is positive.

To satisfy the floating requirement of the display image, the image distance I1 of the primary image must be greater than the distance A. Since the display image generated by the present invention is a real image, the distance A must be greater than one-fourth of the radius of curvature R2. By combining the above elements, the relational expression 5 can be derived.

Equation 10

In other words, by selecting a radius of curvature R2 of the mirror structure 610 that satisfies the above relationship, the floating projection device 600 can effectively generate a display image as a hologram image.

The floating projection device of the present invention has a mirror structure and an optical structure correspondingly installed. With the optical coating installed on the optical structure, the image beam generated by the display can be reflected multiple times between the optical coating and the optical structure to convert the polarization form of the image beam. The optical coating can transmit the image beam with a specific polarization form above the floating projection device to generate a hologram image above the floating projection device. Thus, the display image generated by the floating projection device can have a relatively wide viewing angle, and the image beam generated by the display will not directly enter the user's eyes, so that the occurrence of visual interference can be effectively avoided.

The present invention can be applied to floating projection related products and can improve the image display quality of floating projection devices.

100, 400, 500, 600: Floating projection device 110, 410, 510, 610: Mirror structure 120, 420, 520, 620: Optical structure 130, 430, 530, 630: Optical coating 140, 440, 540, 640: Display A, L: Distance IMB, IMB1, IMB2: Image beam IMP: Imaging plane IQPS: Polarization selective reflection film layer QWP: Retardation film layer RB1, RB2, RB11, RB21, RB12, RB22: Reflection beam SI: Inner surface SO: Outer surface Z1: Storage space

Claims (10)

A mirror structure;
an optical structure covering the mirror structure and forming a storage space between the mirror structure and the optical structure;
an optical coating disposed on the optical structure, the optical coating comprising: a retardation film layer; and a polarization selective reflection film layer disposed between the inner surface of the mirror structure and the retardation film layer ;
a display disposed in the receiving space formed between the optical structure and the mirror structure, the display being used to transmit a plurality of image beams toward the optical structure;
A floating projection device comprising: 2. The floating projection device of claim 1, wherein the plurality of image beams undergo a first reflection on an inner surface of the optical structure to generate a plurality of first reflected beams, the plurality of first reflected beams undergo a second reflection on a reflective surface of the mirror structure to generate a plurality of second reflected beams, and the plurality of second reflected beams pass through the inner surface of the optical structure to form a real displayed image. 3. The floating projection device of claim 2, wherein the display projects the plurality of image beams of circularly polarized light having a first rotatory power, the retardation film layer converts the plurality of image beams into linearly polarized light in a first direction, the polarization selective reflection film layer reflects the plurality of image beams of linearly polarized light in the first direction to generate the plurality of first reflected beams, and the retardation film layer further converts the plurality of first reflected beams into circularly polarized light having the first rotatory power. 3. The floating projection device of claim 2 , wherein a reflective surface of the mirror structure reflects the first reflected beams to generate the second reflected beams of circularly polarized light having a second rotational orientation. 5. The floating projection device of claim 4, wherein the retardation film layer converts the second reflected beams into linearly polarized light in a second direction, and the polarization selective reflection film layer passes the second reflected beams of linear polarization in the second direction. The floating projection device of claim 1 , wherein a display image is imaged adjacent an outer surface of the optical structure outside of the containment space. The floating projection device of claim 1, wherein the mirror structure and the optical structure have a first radius of curvature and a second radius of curvature, respectively, and the first radius of curvature and the second radius of curvature are non-zero real numbers. 8. The floating projection device of claim 7 , wherein the concave surface of the mirror structure and the concave surface of the optical structure face each other. The floating projection device of claim 1, wherein one of the mirror structure and the optical structure is a planar structure, and the other of the mirror structure and the optical structure has a constant radius of curvature, the radius of curvature being a non-zero real number. The floating projection device of claim 1, wherein the optical structure is a transparent structure.