Ultra-large Flexible Holographic Screen and Rigid Holographic Screen Based on Ultra-large Application Scenarios

Abstract

The present invention relates to the field of 3D displays, and discloses a super-large flexible holographic screen based on a super-large application scenario, which includes a number of flexible holographic projection units arranged in a matrix and bonded together. Both the super-large flexible holographic screen and the flexible holographic projection units are flexible and bendable structures. The flexible holographic projection unit is formed by bonding two layers of flexible elementary films with transparent glue. A single-layer flexible elementary film is composed of a number of alternately parallel arranged reflective layers and transparent layers. Compared with the existing high-precision optical glass processing, on the one hand, the material cost of the flexible elementary film is lower, and on the other hand, when processing it, it is not easy to break, and problems such as residual stress generated during the glass processing will not occur, greatly improving the yield rate, making it suitable for large-scale promotion. At the same time, the flexible holographic film can be made into a rollable screen, a curved screen, etc., with high flexibility, convenient storage when not in use, and small occupied space.

Description

Technical Field

[0001] The present invention relates to the field of 3D displays, and more particularly to ultra-large flexible holographic screens and rigid holographic screens based on ultra-large application scenarios. Background Art

[0002] 3D display technology can display stereoscopic images in space and is the mainstream direction of the next-generation display technology. Although there are already many solutions for achieving 3D displays, such as volumetric display technology, stereoscopic image pair technology, Pepper's ghost, etc., there is currently no perfect 3D solution. The main reason is the lack of optical glass elements for controlling large-area light sources.

[0003] Traditional optical glass processing technology can only perform micro-structure processing at the scale of hundreds of micrometers. Higher-precision large-area optical processing requires extremely high processing costs, and the optical glass itself is a hard material, so problems such as breakage and residual stress are likely to occur during the processing.

[0004] Larger 3D display projection screens are usually from a dozen inches to dozens of inches, but ultra-large 3D display projection screens are generally from dozens of inches to hundreds of inches (diagonal), or even larger. When used in practical applications in large open-air scenarios such as football fields or other ultra-large open-air scenarios, due to reasons such as manufacturing processes, installation, transportation, and machinery, it is usually necessary to assemble several smaller projection units into an ultra-large holographic projection screen. Coupled with the fragile characteristics of the optical glass that makes up each projection unit, some structures are also required to protect and support the glass of each projection unit, making the overall holographic projection screen heavier and less conducive to disassembly, installation, and maintenance. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: in view of the above deficiencies of the prior art, to provide ultra-large flexible holographic screens and rigid holographic screens based on ultra-large application scenarios.

[0006] To solve the above technical problem, the technical solution proposed by the present invention is:

[0007] An ultra-large flexible holographic screen based on an ultra-large application scenario, comprising a plurality of flexible holographic projection units arranged in a matrix and bonded together. Both the ultra-large flexible holographic screen and the flexible holographic projection units are flexible and bendable structures. The flexible holographic projection unit is formed by bonding two layers of flexible base films with transparent glue. Each single-layer flexible base film is composed of a plurality of alternately parallel reflection layers and transparent layers;

[0008] The reflection layer is a reflection film with the function of reflecting light, used for reflecting light;

[0009] The transparent layer is used for transmitting light;

[0010] The reflective layer and the transparent layer between the two flexible elementary films forming the flexible holographic projection unit are staggered at an angle θ to form a grid (4), where 87° ≤ θ ≤ 93°, preferably 90°;

[0011] The horizontal clamping sag length of the flexible holographic projection unit is H (cm) and the number of times it can be folded in half is n, satisfying:

[0012] H ≥ 5 or n * H > 9;

[0013] For the transparent layer of the flexible holographic screen with a thickness of d (μm) and the longest side of L (cm), the relationship between them satisfies:

[0014] 1 < d / L < 10.

[0015] Further, the thickness of the reflective layer is 0.1 μm to 25 μm, the thickness of the transparent layer is 1 mm to 10 cm, and the thickness of the transparent layer is greater than that of the reflective layer.

[0016] Further, the reflective film is any one of aluminum foil, iron foil, tin foil, zinc foil, copper foil, chromium foil, nickel foil, and titanium foil.

[0017] Further, the transparent layer is a cured layer of transparent glue and / or a transmissive film layer bonded by transparent glue.

[0018] Further, the transparent glue is any one of transparent epoxy AB glue, UV glue, shadowless glue, transparent glass glue, transparent woodworking glue, and transparent universal glue.

[0019] Further, the transmissive film is any one of plastics of transparent materials, PMMA film, lPMMA film, PS film, PC film, styrene acrylonitrile film, MS film, PET film, PETG film, ABS film, PP film, PA film, SAN film, MS film, MBS film, PES film, CR-39 film, TPX film, HEMA film, F4 film, F3 film, EFP film, PVF film, PVDF film, EP film, PF film, UP film, cellulose acetate film, cellulose nitrate film, EVA film, PE film, PVC film, amorphous cycloolefin film, and modified bisphenol A epoxy resin film.

[0020] Further, a flexible transparent protective film is bonded to a single-layer flexible elementary film by transparent glue.

[0021] Further, the flexible transparent protective film is any one of PMMA film, PMMA film, PS film, PC film, styrene acrylonitrile film, MS film, PET film, PETG film, ABS film, PP film, PA film, SAN film, MS film, MBS film, PES film, CR-39 film, TPX film, HEMA film, F4 film, F3 film, EFP film, PVF film, PVDF film, EP film, PF film, UP film, cellulose acetate film, cellulose nitrate film, EVA film, PE film, PVC film, amorphous cycloolefin film, and modified bisphenol A epoxy resin film made of transparent materials.

[0022] The present invention also provides an extra-large rigid holographic screen based on an extra-large application scenario, which includes an extra-large rigid transparent flat plate and the above-mentioned extra-large flexible holographic screen adhered to the rigid transparent flat plate.

[0023] The extra-large rigid holographic screen based on an extra-large application scenario includes a number of rigid holographic projection units arranged in a matrix and bonded together. The rigid holographic projection unit is formed by bonding two layers of rigid elementary films with transparent glue, or is formed by bonding one layer of the above-mentioned flexible elementary film and one layer of rigid elementary film with transparent glue. The rigid elementary film is a flexible elementary film bonded with a layer of rigid transparent protective film.

[0024] Further, the transparent protective film is any one of glass, acrylic, and plastic made of transparent materials.

[0025] Compared with the prior art, the advantages of the present invention are as follows:

[0026] 1. Both the extra-large flexible holographic screen and the extra-large rigid holographic screen described in the present invention include flexible elementary films. Compared with the existing high-precision optical glass processing, on the one hand, the material cost of the flexible elementary film is lower, and on the other hand, when processing it, it is not easy to break, and problems such as residual stress generated during the glass processing process will not occur, greatly improving the yield rate and being suitable for large-scale promotion.

[0027] 2. The extra-large flexible holographic screen described in the present invention is flexible itself, so that in specific applications, it can be made into a rollable screen, a curved screen, etc., without adding heavy supports and protections, with high flexibility, convenient storage when not in use, and small occupied space.

[0028] 3. On the basis of the flexible elementary film, by adding a rigid transparent protective film, it is applied to the extra-large rigid holographic screen, making the overall extra-large rigid holographic screen not easy to break, reducing the heavy protection required during application, and being more convenient for maintenance. Description of the Drawings

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 This is the front view of the ultra-large flexible holographic screen or ultra-large rigid holographic screen described in the present invention.

[0031] Figure 2 This is the ultra-large rigid holographic screen with the ultra-large flexible holographic screen adhered to the ultra-large rigid transparent flat plate 5.

[0032] Figure 3 This is the three-dimensional structure diagram of the flexible holographic projection unit 1.

[0033] Figure 4 For Figure 3 the front view and top view of

[0034] Figure 5 This is the front view of the flexible elementary film 2 with the transparent layer 22 being the transparent glue curing layer.

[0035] Figure 6 This is the front view of another flexible elementary film 2 with the transparent layer 22 composed of transparent glue and a transmissive film.

[0036] Figure 7 For Figure 6 the partial enlarged view of I in

[0037] Figure 8 This is the structure diagram of the rigid holographic projection unit 6 composed of one layer of flexible elementary film 2 and one layer of rigid elementary film 7.

[0038] Figure 9 This is the structure diagram of the rigid holographic projection unit 6 composed of two layers of rigid elementary film 7 or one layer of flexible elementary film 2 with a transparent protective film 4 and one layer of rigid elementary film 7.

[0039] Figure 10 This is the imaging principle diagram of the flexible holographic projection unit 2 or the rigid holographic projection unit 6.

[0040] Figure 11 For Figure 7 the side view of

[0041] Figure 12 For Figure 11 the partial internal light reflection principle diagram of II in

[0042] Figure 13It is an imaging effect diagram of an ultra - large flexible holographic screen or an ultra - large rigid holographic screen.

[0043] Figure 14 It is an imaging optical path simulation effect diagram of the ultra - large flexible holographic screen or the ultra - large rigid holographic screen described in the present invention.

[0044] The reference numerals are as follows:

[0045] Flexible holographic projection unit 1, flexible elementary film 2, reflective layer 21, transparent layer 22, grid 3, flexible transparent protective film 4, transparent flat plate 5, rigid holographic projection unit 6, rigid elementary film 7, rigid transparent protective film 8. Detailed implementation manners

[0046] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings. The description in this part is only exemplary and explanatory, and should not have any restrictive effect on the protection scope of the present invention.

[0047] The ultra - large flexible holographic screen based on an ultra - large application scenario includes a number of flexible holographic projection units 1 arranged in a matrix and bonded together. Both the ultra - large flexible holographic screen and the flexible holographic projection unit 1 are flexible and bendable structures. The flexible holographic projection unit 1 is formed by bonding two layers of flexible elementary films 2 with transparent glue. A single - layer flexible elementary film 2 is composed of a number of alternately parallel - arranged reflective layers 21 and transparent layers 22;

[0048] The reflective layer 21 is a reflective film with the function of reflecting light for reflecting light. It should be noted that if the reflective film is too thick, it will block too much light, and the thinner the better. However, considering the process preparation difficulty and cost, the thickness of the reflective film is selected from aluminum foil, iron foil, tin foil, zinc foil, copper foil, chromium foil, nickel foil, titanium foil with a thickness of 0.1μm - 25μm or other reflective films that can reflect light;

[0049] The transparent layer 22 is a cured layer of transparent glue and / or a transmissive film layer bonded with transparent glue for transmitting light, and it is ensured that the thickness of the transparent layer 22 is always greater than the thickness of the reflective layer 21. The thickness of the transparent layer is preferably 1㎜ - 10㎝;

[0050] The transparent glue is any one of transparent epoxy AB glue, UV glue, shadowless glue, transparent glass glue, transparent wood glue and transparent all - purpose glue;

[0051] The transmissive film is any one of plastics, PMMA film, lPMMA film, PS film, PC film, styrene acrylonitrile film, MS film, PET film, PETG film, ABS film, PP film, PA film, SAN film, MS film, MBS film, PES film, CR-39 film, TPX film, HEMA film, F4 film, F3 film, EFP film, PVF film, PVDF film, EP film, PF film, UP film, cellulose acetate film, cellulose nitrate film, EVA film, PE film, PVC film, amorphous cycloolefin film and modified bisphenol A epoxy resin film, which are made of transparent materials;

[0052] Between the reflective layer 21 and the transparent layer 22, they can be bonded together by transparent glue, or the reflective film can be directly plated on the transparent layer 22;

[0053] The reflective layer 21 and the transparent layer 22 between the two flexible elementary films 2 that make up the flexible holographic projection unit 1 are staggered at an angle θ to form a grid 3, where 87° ≤ θ ≤ 93°, preferably 90°. The flexible elementary film 2 that makes up the flexible holographic projection unit 1 can be bonded with at least one layer of flexible transparent protective film 4 by transparent glue;

[0054] The flexible transparent protective film 4 is any one of PMMA film, lPMMA film, PS film, PC film, styrene acrylonitrile film, MS film, PET film, PETG film, ABS film, PP film, PA film, SAN film, MS film, MBS film, PES film, CR-39 film, TPX film, HEMA film, F4 film, F3 film, EFP film, PVF film, PVDF film, EP film, PF film, UP film, cellulose acetate film, cellulose nitrate film, EVA film, PE film, PVC film, amorphous cycloolefin film and modified bisphenol A epoxy resin film, which are made of transparent materials;

[0055] The transparent layer 22 is a cured layer of transparent glue and / or a transmissive film layer bonded by transparent glue. Based on the materials of the above transparent glue and transmissive film, the cured transparent layer 22 has good flexibility, so that the flexible elementary film 1 and the flexible holographic screen both have good flexibility;

[0056] The flexible holographic projection unit 1 can be used alone as a flexible 3D display holographic film. Its horizontal clamping sag length is H (cm) and the number of times it can be folded is n, satisfying: H ≥ 5 or n * H > 9. In actual application, in order to ensure reliability as much as possible, it is preferably n ≥ 2 and H > 9;

[0057] It should be noted that n is the number of times it can be folded. When testing, an area of 100 cm 2A flexible 3D display holographic film in the shape of a square. Fold the holographic film along the middle line of the square (or within a range of 1 cm near the middle line position) into a rectangle, then sandwich the folded holographic film between two flat plates, apply a force of 10 - 20 N, press for 3 - 5 s, and then open the holographic film (at this time, one folding test is completed). Check whether the holographic film is broken into two sections along the crease. If it is not broken, repeat the above test until the holographic film is broken into two sections, and then stop the test. The total number of folding times during the test process is recorded as n;

[0058] Where H is the horizontal clamping sag length. The test method: Take a narrow strip of holographic film with a width of 5 cm ± 0.5 cm and a length of about 25 cm. One end is closely attached to a horizontal reference tabletop, ensuring that the length of the narrow strip extending out of the tabletop is 20 cm ± 1 cm. Then, wait for the narrow strip to stabilize and measure the vertical height difference between the end point of the narrow strip extending out of the tabletop and the horizontal reference tabletop, which is recorded as the horizontal sag length H;

[0059] The above test itself is an accelerated test method, which can quickly judge the reliability of the sample during long-term use. When the holographic film is applied, it needs to withstand multiple operations such as winding and unfolding. Calculated according to the designed service life of 5 years, the entire life cycle requires about 10,000 times of storage and unfolding actions. In order to accelerate the evaluation of the life of the holographic film, the present invention adopts the above folding test and horizontal clamping sag length test.

[0060] When n * H > 9, the larger n is, the smaller the limiting bending curvature radius of the holographic film is, and the stronger the anti-breaking ability is. At the same time, the larger L is, the better the flexibility of the holographic film is, and it is less likely to damage the holographic film structure due to winding. Experiments have found that when n * H = 9, it is basically equivalent to 10,000 times of opening and closing tests, meeting the minimum design life requirements. If it is too small, quality problems are likely to occur during the product usage cycle, reducing the customer experience.

[0061] In actual application, some relatively hard transparent glues and transparent films after curing can also be used. The prepared holographic film will break when folded, but the structure will not be damaged when wound, so it is also applicable to wound screens. For such materials, as long as the prepared flexible 3D display holographic film can be wound into a cylindrical shape with a diameter less than 5 cm, the flexible 3D display holographic film is relatively compliant as a whole, and the loss during the processing process is also small. When H > 5 cm, the holographic film can be relatively easily wound into a cylindrical shape with a diameter less than 5 cm.

[0062] The present invention also provides an ultra-large rigid holographic screen based on an ultra-large application scenario, including an ultra-large rigid transparent flat plate 5 and the above-mentioned ultra-large flexible holographic screen adhered to the rigid transparent flat plate 5. Based on the influence of wind in some open-air ultra-large application scenarios, the above-mentioned ultra-large flexible holographic screen can be adhered to the ultra-large rigid transparent flat plate 5 to form an ultra-large rigid holographic screen, thereby improving its stability.

[0063] The present invention also provides another ultra-large rigid holographic screen, which includes a number of rigid holographic projection units 6 arranged in a matrix and bonded together. The rigid holographic projection unit 6 is formed by bonding two layers of rigid elementary films 7 with transparent glue, or is formed by bonding the above-mentioned flexible elementary film 2 and a layer of rigid elementary film 7 with transparent glue. The rigid elementary film 7 is formed by bonding a layer of rigid transparent protective film 8 on the flexible elementary film 2. The rigid transparent protective film 8 is any one of glass, acrylic, and plastic with a transparent material, and acrylic is preferred.

[0064] Except for materials such as glass and acrylic that are relatively hard themselves, when the transparent protective film is the material that the above-mentioned flexible transparent protective film 4 can adopt, when the thickness of the transparent protective film is relatively large, it is also a relatively hard transparent protective film, which is also applicable to the rigid holographic projection unit 6.

[0065] The thickness of the transparent layer 22 of the above-mentioned flexible holographic screen or rigid holographic screen is d (μm), and the longest side is L (cm), satisfying:

[0066] 1 < d / L < 10;

[0067] It should be noted that during actual imaging, if the resolution of the holographic screen is higher, the more information the human eye can recognize, and the clearer and more comfortable it is to watch. However, the human eye has a limit angular resolution ability, which is approximately 1′ (1 / 60 of 1°). If the resolution of the holographic screen is much higher than the resolution limit of the human eye, at this time, the micro-structure of the holographic screen needs to be made very fine, and the corresponding manufacturing cost is also higher. At the same time, the overly fine structure will also bring problems of light diffraction, thereby reducing the imaging quality;

[0068] If the resolution of the holographic screen is too poor, far lower than the resolution of the human eye, then the clarity of the picture will be very poor, and the viewing experience will also be greatly reduced. Therefore, the micro-structure design of the holographic screen needs to match the characteristics of the human eye;

[0069] When the human eye views an object in the distance, its detail resolution ability will become poor, and the human eye cannot recognize too small detail points. On the contrary, when viewing a nearby object, it can recognize the detail information well;

[0070] Generally, the larger the holographic screen is, the farther away we can watch it. If the holographic screen is smaller, we must get closer to watch it comfortably. Therefore, for a large holographic screen, it can be placed at a farther distance for viewing. At this time, the microstructure of the holographic screen can be made relatively "coarse". The thickness of the transparent layer 22 on the holographic screen is d (μm), and the longest side of the projection screen is L (cm). When L exceeds 0.6 m and d is small, the processing difficulty increases sharply in the form of a power function with the increase of the screen length. At this time, in order to balance the processing difficulty and the display effect, considering the characteristics of the human eye resolution, the manufacturing process difficulty, and the imaging effects such as diffraction, d should be increased accordingly. For an extremely large holographic screen, the length of L should reach at least more than 100 m, and then d should also be increased to about 10 cm according to the actual situation. To sum up, the following relationship should be satisfied between d and L: 1 < d / L < 10, so that all aspects can be taken into account. For the specific dimensions, please refer to the following table:

[0071] Thickness of transparent layer / μm Longest side of projection screen / cm Formula d L 1 < d / L < 10 100 34.4 2.91 100 100 1 300 100 3 1000 100 10 100000 10000 10

[0072] Imaging principle: The projected light is reflected by the reflection layer 21 inside the holographic screen, with one or more reflections, and a 3D image is formed at the position conjugate to the holographic screen. The final imaging effect of this imaging principle is the same as that of a flat lens made of negative refractive index material.

[0073] The above content is a further detailed description of the present invention in combination with specific preferred embodiments. It cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, without departing from the concept of the present invention, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. An ultra-large flexible holographic screen based on an ultra-large application scenario, characterized in that: It includes a number of flexible holographic projection units (1) arranged in a matrix and bonded together. Both the ultra-large flexible holographic screen and the flexible holographic projection unit (1) are flexible and bendable structures. The flexible holographic projection unit (1) is formed by bonding two layers of flexible elementary films (2) with transparent glue. A single-layer flexible elementary film (2) is composed of a number of alternately parallel arranged reflective layers (21) and transparent layers (22). The reflective layer (21) is a reflective film with the function of reflecting light, used to reflect light. The transparent layer (22) is used to transmit light. The reflective layer (21) and the transparent layer (22) between the two flexible elementary membranes (2) constituting the flexible holographic projection unit (1) are staggered at an angle θ and form a grid (3). ; The horizontal clamping sag length of the flexible holographic projection unit (1) is H (cm), and the number of times it can be folded in half is n, satisfying: H≥5 or ; The thickness of the transparent layer (22) of the flexible holographic screen is d (μm), and the longest side is L (cm), and they satisfy: 1 < d / L < 10. The thickness of the reflective layer (21) is 0.1 μm to 25 μm, the thickness of the transparent layer (22) is 1 mm to 10 cm, and the thickness of the transparent layer (22) is greater than that of the reflective layer (21).

2. The ultra-large flexible holographic screen based on an ultra-large application scenario according to claim 1, wherein: The reflective film is any one of aluminum foil, iron foil, tin foil, zinc foil, copper foil, chromium foil, nickel foil, and titanium foil.

3. The ultra-large flexible holographic screen based on an ultra-large application scenario according to claim 1, wherein: The transparent layer (22) is a cured layer of transparent glue and / or a transmissive film layer bonded with transparent glue.

4. The ultra-large flexible holographic screen based on an ultra-large application scenario according to claim 1 or 3, characterized in that: The transparent glue is any one of transparent epoxy AB glue, UV glue, shadowless glue, transparent glass glue, transparent woodworking glue, and transparent all-purpose glue.

5. The ultra-large flexible holographic screen based on an ultra-large application scenario according to claim 3, characterized in that: The transmissive film is any one of plastics of transparent materials, PMMA film, lPMMA film, PS film, PC film, styrene acrylonitrile film, MS film, PET film, PETG film, ABS film, PP film, PA film, SAN film, MS film, MBS film, PES film, CR-39 film, TPX film, HEMA film, F4 film, F3 film, EFP film, PVF film, PVDF film, EP film, PF film, UP film, cellulose acetate film, cellulose nitrate film, EVA film, PE film, PVC film, amorphous cycloolefin film, and modified bisphenol A epoxy resin film.

6. The ultra-large flexible holographic screen based on an ultra-large application scenario according to claim 1, characterized in that: A single-layer flexible elementary film (2) is bonded with a flexible transparent protective film (4) through transparent glue.

7. The super-large flexible holographic screen based on a super-large application scenario according to claim 6, characterized in that: The flexible transparent protective film (4) is any one of PMMA film, lPMMA film, PS film, PC film, styrene acrylonitrile film, MS film, PET film, PETG film, ABS film, PP film, PA film, SAN film, MS film, MBS film, PES film, CR-39 film, TPX film, HEMA film, F4 film, F3 film, EFP film, PVF film, PVDF film, EP film, PF film, UP film, cellulose acetate film, cellulose nitrate film, EVA film, PE film, PVC film, amorphous cycloolefin film, and modified bisphenol A epoxy resin film of transparent materials.

8. The ultra-large rigid holographic screen based on an ultra-large application scenario is characterized in that: It includes an ultra-large transparent flat plate (5) and the ultra-large flexible holographic screen as described in claim 1 adhered to the rigid transparent flat plate (5).

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