Fresnel projection screen

Abstract

The embodiment of the invention provides a Fresnel projection screen, the Fresnel projection screen comprises a plurality of functional layers, one of the functional layers of the Fresnel projection screen is a coloring layer, and the coloring layer at least comprises dye; the coloring layer is used for absorbing ambient light transmitted to the Fresnel projection screen from the outside and absorbing reflected light reflected by the Fresnel projection screen; film layer parameters of the coloring layer are kept in a preset numerical value interval, so that the transmittance of the coloring layer is kept in a target transmittance interval; wherein the film layer parameters at least comprise the film layer thickness. Based on the scheme, the film layer parameters of the coloring layer are improved, so that the display effect of the Fresnel projection screen can be better, and the use experience of a user is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of projection display technology, and more specifically, to a Fresnel projection screen. Background Art

[0002] In the field of projection display, especially in the field of ultra-short-throw laser projection display, in order to achieve better brightness and display effects, projectors are generally used with Fresnel projection screens, which are characterized by high gain, small viewing angle, and certain resistance to ambient light.

[0003] Fresnel projection screens are generally composed of multifunctional layers, including surface layer, diffusion layer, coloring layer, Fresnel structure layer and reflection layer, etc. Among them, the coloring layer absorbs ambient light and improves image contrast. The transmittance of the coloring layer directly or indirectly affects the gain of the film and other optical indicators. Summary of the invention

[0004] Some embodiments of the present application provide a Fresnel projection screen, which includes multiple functional layers, and one of the functional layers of the Fresnel projection screen is a coloring layer, which includes at least a dye; the coloring layer is used to absorb ambient light transmitted from the outside to the Fresnel projection screen, and absorb reflected light reflected by the Fresnel projection screen; the film layer parameters of the coloring layer are maintained within a preset numerical range, so that the transmittance of the coloring layer is maintained within a target transmittance range; wherein the film layer parameters include at least the film layer thickness.

[0005] It can be seen from the above technical solution that the embodiment of the present application provides a Fresnel projection screen, and improves the film parameters of the coloring layer of the Fresnel projection screen. Under the premise of the specific film parameters (at least including the film thickness) provided in the embodiment of the present application, the transmittance of the coloring layer is maintained within the target transmittance range. The transmittance directly affects the gain and ambient light shielding rate of the Fresnel projection screen. The higher the transmittance, the more light that passes through the coloring layer to the reflective layer and the more light reflected by the reflective layer, and the higher the brightness of the Fresnel projection screen. The gain is proportional to the brightness and illumination of the diaphragm. For the same illumination conditions, the higher the transmittance, the higher the brightness of the diaphragm, and the higher the gain. When the transmittance of the coloring layer is maintained in the target transmittance range, the gain, ambient light shielding rate and brightness of the Fresnel projection screen are all better, that is, through the improvement of the film parameters of the coloring layer in the embodiment of the present application, the display effect of the Fresnel projection screen can be better, and the user experience can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] In order to more clearly illustrate the implementation methods in the embodiments of the present application or the related technologies, the following is a brief introduction to the drawings required for use in the embodiments or the related technology descriptions. Obviously, the drawings described below are some embodiments of the present application, and a person skilled in the art can also obtain other drawings based on these drawings.

[0007] Figure 1 A schematic diagram of the structure principle of a Fresnel projection screen in a related technical solution;

[0008] Figure 2 A schematic diagram of a Fresnel projection screen structure according to one or more embodiments of the present application;

[0009] Figure 3 A schematic diagram of a surface layer structure of one or more embodiments of the present application;

[0010] Figure 4 A schematic diagram of another surface layer structure according to one or more embodiments of the present application;

[0011] Figure 5 A schematic diagram of another surface layer structure according to one or more embodiments of the present application;

[0012] Figure 6 A schematic diagram of another surface layer structure according to one or more embodiments of the present application;

[0013] Figure 7 A schematic diagram of a Fresnel layer structure according to one or more embodiments of the present application;

[0014] Figure 8 A schematic diagram of another Fresnel layer structure according to one or more embodiments of the present application;

[0015] Fig. 9 A schematic diagram of a diffusion layer structure according to one or more embodiments of the present application;

[0016] Fig.10 A schematic diagram of another diffusion layer structure according to one or more embodiments of the present application;

[0017] Fig.11 A schematic diagram of a curve showing the relationship between the film thickness and the transmittance of the coloring layer according to one or more embodiments of the present application;

[0018] Fig.12 A schematic diagram of the thickness of the colored layer in a wet film state according to one or more embodiments of the present application;

[0019] Fig.13 A schematic diagram of the thickness of the colored layer in a cured state according to one or more embodiments of the present application;

[0020] Fig.14A schematic diagram of a curve showing the relationship between the first mixing ratio and the transmittance of the coloring layer according to one or more embodiments of the present application;

[0021] Fig.15 A schematic diagram of a relationship curve between the amount of blue dye and the gain ratio of one or more embodiments of the present application;

[0022] Fig.16 A schematic diagram of a relationship curve between the amount of red dye and the gain ratio of one or more embodiments of the present application;

[0023] Fig.17 A schematic diagram of a reflective layer structure according to one or more embodiments of the present application;

[0024] Fig.18 A schematic diagram of another reflective layer structure according to one or more embodiments of the present application;

[0025] Fig.19 A schematic diagram of another reflective layer structure according to one or more embodiments of the present application;

[0026] Fig. 20 A schematic diagram of another Fresnel projection screen structure according to one or more embodiments of the present application;

[0027] Fig.21 A schematic diagram of another Fresnel projection screen structure according to one or more embodiments of the present application;

[0028] Fig. 22 A schematic diagram of another Fresnel projection screen structure according to one or more embodiments of the present application. DETAILED DESCRIPTION

[0029] In order to make the purpose, implementation mode and advantages of the present application clearer, the exemplary implementation mode of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0030] Based on the exemplary embodiments described in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the claims attached to this application. In addition, although the disclosure in this application is introduced according to one or several exemplary examples, it should be understood that each aspect of these disclosures can also constitute a complete implementation method separately. It should be noted that the brief description of the terms in this application is only for the convenience of understanding the implementation methods described below, and is not intended to limit the implementation methods of this application. Unless otherwise specified, these terms should be understood according to their common and usual meanings.

[0031] Figure 1FIG. 1 is a schematic diagram of the structure principle of the Fresnel projection screen in the related technical solution; Figure 1 As shown, the Fresnel projection screen 100 is generally used in conjunction with an ultra-short-throw laser projector 200. The ultra-short-throw laser projector 200 is generally set on the ground or at a position close to the ground to emit light L1 to the Fresnel projection screen 100 at a certain angle, and the light L1 is reflected by the Fresnel projection screen 100 to the viewing angle of the user 300, so that the user 300 can view the corresponding content. At the same time, the light L2 on the ceiling (such as light) is reflected by the Fresnel projection screen 100 and propagates to the ground, and cannot be reflected to the user's human eye viewing angle, which can avoid the influence of ambient light on the viewing effect of the human eye.

[0032] The ultra-short-throw laser projector 200 may include a laser machine, which may be one of a monochromatic laser, a two-color laser, and a three-color laser. Among them, the three-color laser can emit a blue laser, a red laser, and a green laser. The wavelength range of the blue laser emitted by the laser can be set to 430nm~460nm, the wavelength range of the emitted green laser can be set to 500nm~540nm, and the wavelength range of the emitted red laser can be set to 610nm~650nm. Since the three-color laser has the advantages of color authenticity and high color gamut, the laser in the ultra-short-throw laser projector 200 provided in the embodiment of the present application can select a three-color laser. Of course, the laser in the ultra-short-throw laser projector 200 provided in the embodiment of the present application can also select a monochromatic laser or a two-color laser.

[0033] Fresnel projection screens generally include multiple functional layers such as a surface layer, a diffusion layer, a coloring layer, a Fresnel layer, and a reflective layer. The coloring layer absorbs ambient light and improves image contrast. It can be roughly understood that the Fresnel projection screen can have a better display effect and less ambient light entering the human eye through the coloring layer. In addition, the coloring layer directly or indirectly affects the optical indicators of the Fresnel projection screen, such as gain and gain ratio.

[0034] Based on the above background, an embodiment of the present application provides a Fresnel projection screen. Figure 2The structure diagram of a Fresnel projection screen of one or more embodiments of the present application is shown in the figure. The Fresnel projection screen 100 includes multiple functional layers, and one of the functional layers of the Fresnel projection screen 100 is a coloring layer 23, in which a dye is doped; the coloring layer 23 absorbs ambient light transmitted from the outside to the Fresnel projection screen 100, and absorbs reflected light reflected by the Fresnel projection screen 100; the film layer parameters of the coloring layer 23 are maintained within a preset numerical range, so that the transmittance of the coloring layer 23 is maintained within a target transmittance range; wherein the film layer parameters at least include the film layer thickness. In some embodiments, the target transmittance can be greater than or equal to 40% and less than or equal to 60%. In some preferred embodiments, the transmittance of the coloring layer 23 can be further maintained within a range greater than or equal to 58% and less than or equal to 60%. The higher the transmittance of the coloring layer 23, the more light that passes through the coloring layer 23 to the reflective layer and is reflected by the reflective layer, and the higher the brightness of the Fresnel projection screen.

[0035] Exemplarily, the Fresnel projection screen may include: Figure 2 The surface layer 21, the diffusion layer 22, the coloring layer 23, the Fresnel layer 24 and the reflective layer 25 are shown as multiple functional layers. The surface layer 21 can be used to protect the Fresnel projection screen 100 and prevent the Fresnel projection screen from being damaged. The diffusion layer 22 is used to increase the viewing angle of the Fresnel projection screen 100, increase the scattering effect of light, and reduce speckle. The Fresnel layer 24 is the core functional layer of the Fresnel projection screen 100, and is used to form Fresnel reflection to reflect ambient light to an angle other than that of the human eye, thereby improving the user's viewing experience. The reflective layer is used to improve the reflectivity and utilization rate of light.

[0036] This application Figure 2 Taking the Fresnel projection screen structure shown as an example, the light projected by the ultra-short-throw laser projector 200 can pass through the surface layer 21, the diffusion layer 22, the coloring layer 23, the Fresnel layer 24 and the reflective layer 25 in sequence. After reaching the reflective layer 25, the light is reflected by the reflective layer 25 and re-emitted from the side where the surface layer 21 is located to the user's human eye perspective.

[0037] Figure 3 This is a schematic diagram of a surface layer structure of one or more embodiments of the present application, see Figure 3 The material of the surface layer can be UV glue. As a simple surface layer, the surface of the surface layer can be flat, which can play a role in protecting the Fresnel projection screen.

[0038] Figure 4 Another schematic diagram of the surface layer structure of one or more embodiments of the present application is shown in FIG. Figure 4, the surface layer can be atomized, and the reflectivity of the light on the surface layer is low after atomization. Therefore, when the light reaches the surface of the surface layer, more light will pass through the surface and enter the interior of the Fresnel projection screen, which improves the utilization rate of the light projected by the ultra-short-throw laser projector, ensures the gain of the Fresnel projection screen, and makes it difficult for the light projected by the ultra-short-throw laser projector to form a clear image in other places (such as the ceiling), ensuring the user's viewing experience.

[0039] Figure 5 Another schematic diagram of the surface layer structure of one or more embodiments of the present application is shown in FIG. Figure 5 A lens (micro lens) can be arranged on the surface layer. By arranging the micro lens, the surface layer forms uneven protrusions, thereby increasing the viewing angle of the Fresnel projection screen, while reducing the reflectivity of the surface and improving the utilization rate of the light projected by the projector. The shape of the micro lens can be hemispherical.

[0040] Figure 6 Another schematic diagram of the surface layer structure of one or more embodiments of the present application is shown in FIG. Figure 6 , the lens set on the surface layer can be atomized to form an atomized lens, so as to combine Figure 4 and Figure 5 The advantages of the embodiment are to ensure the gain of the Fresnel projection screen, increase the viewing angle of the Fresnel projection screen, and reduce reflections from other directions (such as the ceiling).

[0041] Figure 7 A schematic diagram of a Fresnel layer structure of one or more embodiments of the present application, see Figure 7 The Fresnel layer is used to form Fresnel reflection. When the external ambient light passes through the Fresnel layer, it will be reflected to a non-human eye perspective, and the human eye cannot receive the ambient light.

[0042] Figure 8 Another Fresnel layer structure diagram of one or more embodiments of the present application is shown in FIG. Figure 8 In some embodiments, micro lenses may be provided on the surface of the Fresnel layer. By providing the micro lenses, the viewing angle may be increased and the ambient light from the target direction (e.g., the ceiling direction) may be reduced. Dyes may be added to the micro lenses on the surface of the Fresnel layer to form a colored layer, thereby reducing the number of functional layers. Since the number of film layers of the Fresnel projection screen is less, the thickness of the Fresnel projection screen may also be smaller.

[0043] Diffusion particles may be mixed in the diffusion layer, and the absolute value of the difference between the refractive index of the material of the surface layer and the diffusion particles is greater than zero and less than or equal to 0.5. Since the light is more likely to refract when passing through two media with different but similar refractive indices, the refractive index is higher, and when the light passes through two media with large refractive index aberration, the proportion of reflection in the light will be higher. Therefore, when the light projected by the ultra-short-throw laser projector 200 passes through the diffusion layer, the light will diffuse because the refractive index of the diffusion particles in the diffusion layer is different from the refractive index of the material of the surface layer, thereby increasing the viewing angle of the Fresnel projection screen 100. At the same time, since the absolute value of the difference between the refractive index of the material of the surface layer and the refractive index of the diffusion particles in the diffusion layer is less than or equal to 0.5, that is, the refractive index of the two is relatively close, the refractive index of the light projected by the ultra-short-throw laser projector 200 is higher, and the light is not easy to be reflected and directly emitted from the surface layer of the Fresnel projection screen 100, more light can enter the interior of the Fresnel projection screen, and finally reflected into the eyes of the audience, ensuring the gain of the Fresnel projection screen. When the absolute value of the difference between the refractive index of the surface layer and the refractive index of the diffusion particles of the diffusion layer is greater than zero and less than or equal to 0.5, the light can be diffused and the transmittance of the light passing through the diffusion particles of the diffusion layer can be higher, thereby improving the utilization rate of the light and ensuring the gain of the Fresnel projection screen 100. By way of example, the absolute value of the difference between the refractive index of the material of the surface layer and the refractive index of the diffusion particles of the diffusion layer can be 0.5, 0.4, 0.3 or 0.2, etc.

[0044] Fig. 9 This is a schematic diagram of a diffusion layer structure of one or more embodiments of the present application, see Fig. 9 , diffusion particles can be added to the surface layer to form a diffusion layer, and the material of the diffusion particles can be silicon dioxide.

[0045] Fig.10 Another diffusion layer structure schematic diagram of one or more embodiments of the present application, see Fig.10 , diffusion particles can be added to the Fresnel layer to form a diffusion layer.

[0046] Dyes may be mixed in the coloring layer. When external ambient light passes through the coloring layer, it can be absorbed by the dyes in the coloring layer, thereby making the Fresnel projection screen have better resistance to ambient light, that is, the ambient light shielding rate is higher.

[0047] After research, the inventor found that the film thickness of the coloring layer has a great influence on the transmittance of the coloring layer. The transmittance directly affects the gain and ambient light shielding rate. The higher the transmittance, the more light that passes through the coloring layer to the reflective layer and is reflected by the reflective layer, and the higher the brightness. The gain is proportional to the brightness and illumination of the diaphragm. For the same illumination conditions, the higher the transmittance, the higher the brightness of the diaphragm, and the higher the gain. The ambient light shielding rate is related to the ability of the layer to absorb ambient light. The more ambient light is absorbed, the higher the ambient light shielding rate. The coloring layer is generally made of a mixture of dyes and other materials. The coloring layer can be a separate film layer or the same film layer as other functional layers. The coloring layer mainly relies on the dyes in the coloring layer to absorb ambient light. The more dyes there are, the stronger the tinting power is, the stronger its light absorption effect is, and the higher the ambient light shielding rate is.

[0048] After further research, the inventors found that for the film thickness parameter, the transmittance of the coloring layer decreases by about 10% for every 50 μm (unit of length: micrometer) increase in film thickness. Fig.11 The following is a diagram showing the relationship between the film thickness and the transmittance of the coloring layer in one or more embodiments of the present application. In some embodiments, the film thickness of the coloring layer is generally between 10 and 200 μm. The smaller the film thickness, the higher the process requirements for preparing the film, the more difficult it is to control, and the lower the preparation yield. In addition, since the content (or proportion) of the dye in the coloring layer is fixed, the increase in the film thickness of the coloring layer will also lead to an increase in the amount of dye, which in turn leads to an increase in the scattering effect of light, which increases the haze of the coloring layer and affects the viewing effect of the Fresnel projection screen. Generally speaking, the haze of the coloring layer is controlled between 2% and 5%.

[0049] In summary, although the transmittance of the coloring layer has a positive optimization effect on the gain of the Fresnel projection screen, it will also lead to a decrease in the ambient light shielding rate, an increase in haze and an increase in the difficulty of preparation. The inventors set a specific film thickness to keep the transmittance of the coloring layer between 40% and 60%. It should be noted that the transmittance of the coloring layer is not only affected by the thickness of the first film layer of the coloring layer, but also by other film layer parameters. Under the coordinated effect of the first film layer thickness and other film layer parameters, the transmittance of the coloring layer is maintained between 40% and 60%.

[0050] Exemplarily, the coloring layer can be formed by mixing a dye and a preset material, and the preset material can be a UV glue, that is, the coloring layer can be formed by mixing the dye and the UV glue in a first mixing ratio and then coating the mixture on the substrate to form the coloring layer, and the coloring layer can be used as an adhesive layer to bond the surface layer and the reflective layer together. The coloring layer is coated on the surface of the substrate in a wet film state, and gradually changes from the wet film state to a cured state after coating, and the film thickness decreases accordingly. Fig.12 This is a schematic diagram of the film thickness of the coloring layer in a wet film state according to one or more embodiments of the present application. Fig.13 This is a schematic diagram of the film thickness of the coloring layer in the cured state of one or more embodiments of the present application. The film thickness of the coloring layer in the wet film state is H1, and the film thickness of the coloring layer in the cured state is H2. The film thickness H1 of the coloring layer in the wet film state is between 80 and 120 μm; the film thickness of the coloring layer in the cured state is between 50 and 70 μm. The thickness of the coloring layer directly affects the hardness and rollability of the Fresnel projection screen. When the overall thickness of the Fresnel projection screen is large, its stiffness and hardness are high, but its flexibility is poor; when the overall thickness of the Fresnel projection screen is small, its flexibility is good, which is convenient for curling and transportation, but it is easy to deform. Preferably, in the embodiment of the present application, in order to obtain better flexibility, the thickness of the coloring layer after curing is further maintained at 50 to 60 μm.

[0051] Between μm.

[0052] Furthermore, for dyes of fixed mass and ratio, the more UV glue there is, the stronger the dilution effect on the fuel and the higher the transmittance. In other words, the higher the first mixing ratio, the higher the transmittance of the coloring layer. As the transmittance of the coloring layer increases, the ability of the coloring layer to absorb ambient light decreases, and the ambient light shielding rate decreases. In other words, the user can see more ambient light reflected by the Fresnel projection screen, affecting the user's experience. Fig.14 The diagram is a curve diagram of the relationship between the first mixing ratio and the transmittance of the coloring layer in one or more embodiments of the present application; generally speaking, when the UV glue increases by 0.5 times, the transmittance of the coloring layer increases by 12% to 16%, and the ambient light shielding rate decreases by 5% to 8%. In the embodiment of the present application, the ratio interval of the first mixing ratio is between 150:1 and 170:1. When the first mixing ratio is 150:1, the transmittance of the coloring layer is about 45%. Preferably, the first mixing ratio can be 150:1, and the film thickness in the wet film state can be 100μm, or the film thickness in the cured state can be 60μm. When the thickness of the coloring layer after curing is maintained between 50 and 60μm, the first mixing ratio can be between 160 and 170:1. In some other embodiments, when the thickness of the coloring layer is 100μm, the first mixing ratio can be maintained between 170: and 180:1, and when the thickness of the coloring layer is 200μm, the first mixing ratio can be between 290 and 300:1.

[0053] In some embodiments, the dye in the coloring layer may include red dye, blue dye and black dye; the red dye, blue dye and black dye are mixed according to a second mixing ratio; wherein the second mixing ratio is the mass ratio between the red dye, the blue dye and the black dye.

[0054] Exemplarily, the evaluation of the gain of the Fresnel projection screen may include white gain, red gain, green gain and blue gain. In addition, there is a numerical ratio of the red, green and blue field gains, called the RGB gain ratio, which is represented by R:G, R:B, and G:B. The gain ratio affects the hue of the image. The debugging of the gain ratio is usually achieved by changing the second mixing ratio. When preparing the coloring layer, it is necessary to set a reasonable second mixing ratio to make the RGB gain ratio within a reasonable range. The dye of the coloring layer is usually composed of black dye, blue dye and red dye, black is usually carbon powder, and blue and red are organic nanoparticles.

[0055] Among them, black dye has strong light absorption. When the proportion of black dye is high, the transmittance of the coloring layer decreases, the gain value decreases, but the ambient light shielding rate increases, and the image contrast increases. The proportion of black dye affects red gain, green gain, and blue gain, and the effect on blue gain is the most obvious, followed by green gain, and red gain has the least effect. Reducing the proportion of black dye increases the R:G, R:B, and G:B gain ratios, and the R:B increase is the most obvious.

[0056] The proportion of blue dye has little effect on the transmittance and ambient light shielding rate of the coloring layer, and mainly affects the red gain and blue gain. Under the premise that the proportions of other color dyes remain unchanged, as the proportion of blue dye increases, the red gain gradually decreases and the blue gain gradually increases. For the gain ratio, the R:B, G:B and R:G gain ratios all decrease, with R:B decreasing most significantly, followed by R:G, and G:B the least. Fig.15 The following is a graph showing the relationship between the amount of blue dye and the gain ratio of one or more embodiments of the present application. The horizontal axis is the amount of blue dye dropped into the coloring layer, and each drop of blue dye is about 20 mg. For the coloring layer made of a mixture of UV glue and dye, the mass proportion of blue dye can be between 1‰ and 6‰.

[0057] Generally speaking, the red dye has the lowest ratio, and the red dye ratio has a lower impact on transmittance. Under the premise that the ratios of other color dyes remain unchanged, as the red dye ratio increases, the white gain, green gain, and blue gain all decrease. At the same time, the R:G and R:B gain ratios increase, and the G:B gain ratio slowly decreases. Fig.16 The following is a diagram showing the relationship between the amount of red dye and the gain ratio of one or more embodiments of the present application. The horizontal axis is the amount of red dye dripped into the coloring layer, and each drop of red dye is about 18 mg. For the coloring layer made of a mixture of UV glue and dye, the mass proportion of red dye can be between 0.9‰ and 4.5‰.

[0058] After research, the inventors found that when the second mixing ratio is between 5 to 8:4 and 6:1, the RGB gain ratio is optimal.

[0059] In some embodiments, the coloring layer may be made of a mixture of dye and polyethylene terephthalate (PET). Exemplarily, the Fresnel projection screen may further include a substrate layer, which may be located between the surface layer and the reflective layer, and which may serve as a supporting base for the Fresnel projection screen. In the embodiments of the present application, a dye may also be added to the substrate layer during the preparation process to prepare the coloring layer and the substrate layer as a film layer, thereby reducing the number of functional layers. Since the Fresnel projection screen has fewer film layers, the thickness of the Fresnel projection screen may also be smaller. After the dye is mixed with the PET material, the coloring layer may also be made more uniform.

[0060] In some embodiments, the substrate layer can be a single-layer PET or a double-layer PET. Under the premise of setting a single-layer PET substrate layer, the Fresnel projection screen has better flexibility, can be rolled up for use, and has a lower cost. In addition, for the setting of the substrate layer, other flexible materials can also be used, such as thermoplastic polyurethanes (TPU) materials. TPU has elasticity and can be rolled up; or PU (polyurethane) materials. PU has excellent rubber properties and can be used to bond substrates with different thermal expansion coefficients. A soft-hard transition layer is formed between the substrates, which has strong adhesion and better integration with other functional layers of the screen. It also has excellent buffering and shock absorption functions, but the cost is relatively high; or PVC (polyvinyl chloride) materials, PVC material has good dimensional stability, good weather resistance, low cost, and can be easily adjusted in hardness and softness by using plasticizers; or PP (polypropylene) material, which is easy to dye, light in texture, good in toughness, and good in temperature and chemical resistance; or PE (polyethylene) material, which is odorless, non-toxic, has excellent low temperature resistance, good chemical stability, can withstand most acid and alkali corrosion, and is insoluble in general solvents at room temperature, has low water absorption, and excellent electrical insulation; or MS material, which has a higher hardness and cannot be curled, but has better flatness; or Styrene block copolymer (Styrenic The SBC material is made of flexible material. The SBC material is flexible, waterproof, and has good mechanical properties. It has higher tensile strength, tear strength, and ball bursting strength than MS material. The SBC material can be curled arbitrarily without deformation. It is also resistant to oxidation and has excellent waterproof, weather resistance, chemical resistance, and corrosion resistance. The lower surface of the SBC material is rough and has a three-dimensional network structure. It has good bonding strength with a variety of adhesives and can be blended with PP (polypropylene), PVC (polyvinyl chloride), PE (polyethylene) and other materials to improve the performance and strength of the material.

[0061] In some embodiments, diffusion particles may also be added to the substrate layer to form a diffusion layer, such as adding diffusion particles to a single-layer substrate layer, adding diffusion particles to one layer of a double-layer substrate layer, adding diffusion particles to both layers of a double-layer substrate layer, and so on.

[0062] Fig.17 This is a schematic diagram of a reflective layer structure of one or more embodiments of the present application. In some embodiments, a dye can be added to the reflective layer so that the coloring layer and the reflective layer become the same film layer, thereby improving the utilization rate of light and reducing the number of functional layers. Since the Fresnel projection screen has fewer film layers, the thickness of the Fresnel projection screen can also be smaller.

[0063] Fig.18This is another schematic diagram of the reflective layer structure of one or more embodiments of the present application. In some embodiments, a powdered aluminum powder layer can be provided on the surface of the reflective layer. The powdered aluminum powder layer is more delicate and has less obvious directionality. Most of the light projected by the ultra-short-focus laser projector can be reflected out of the projection screen in a direction according to the structural setting of the Fresnel layer, and will not cause the light to be reflected everywhere, so that the gain of the Fresnel projection screen is higher. In the process of preparing the powdered aluminum powder layer, a spray printing or evaporation process can be used.

[0064] Fig.19 This is a schematic diagram of another reflective layer structure of one or more embodiments of the present application. In some embodiments, a flaky aluminum powder layer may be further provided on the surface of the reflective layer. The aluminum powder particles of the flaky aluminum powder layer are larger, have better adhesion, and are not easily separated from the Fresnel layer. A spray printing process may be used in the process of preparing the flaky aluminum powder layer.

[0065] In some embodiments, the reflective material of the reflective layer may also be silver, or a combination of silver and aluminum, and the like.

[0066] Fig. 20 Another schematic diagram of the structure of a Fresnel projection screen according to one or more embodiments of the present application is shown in FIG. 1 . The Fresnel projection screen 100 may include a surface layer 21, a substrate layer 26, a Fresnel layer 24, and a reflective layer 25 arranged in sequence, wherein a dye is added to the reflective layer 25 to form a coloring layer 23, so that the Fresnel projection screen 100 may reduce one functional layer. The advantages of each functional layer have been described in the above embodiments and will not be repeated here.

[0067] Fig.21 Another schematic diagram of the structure of a Fresnel projection screen according to one or more embodiments of the present application is shown in FIG. 1 . The Fresnel projection screen 100 may include a surface layer 21, a substrate layer 26, a lens layer 27, an OCA adhesive layer 28, a lens layer 27, a substrate layer 26, a Fresnel layer 24, and a reflective layer 25 arranged in sequence, wherein a dye is added to the reflective layer 25 to form a coloring layer 23, so that the Fresnel projection screen 100 may reduce one functional layer. The advantages of each functional layer have been described in the above embodiments and will not be repeated here.

[0068] Fig. 22 This is another schematic diagram of the structure of a Fresnel projection screen according to one or more embodiments of the present application. The Fresnel projection screen may include a surface layer 21, a substrate layer 26, an OCA adhesive layer 28, a coloring layer 23, an OCA adhesive layer 28, a substrate layer 26, a Fresnel layer 24, and a reflective layer 25, which are arranged in sequence. The coloring layer 23 is a separate functional layer, the surface layer 21 is provided with an atomized lens, and the surface layer 21 is doped with diffusion particles to form a diffusion layer 22. The advantages of each functional layer have been described in the above embodiments and will not be repeated here.

[0069] For the convenience of explanation, the above description has been made in conjunction with specific embodiments. However, the above discussion in some embodiments is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. According to the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. A Fresnel projection screen, characterized in that: The Fresnel projection screen comprises a plurality of functional layers, and one of the functional layers of the Fresnel projection screen is a coloring layer, and the coloring layer comprises at least a dye; The coloring layer absorbs ambient light transmitted from the outside to the Fresnel projection screen, and absorbs reflected light reflected by the Fresnel projection screen; The film parameters of the coloring layer are maintained within a preset value range, so that the transmittance of the coloring layer is maintained within a target transmittance range; Wherein, the film layer parameters at least include the film layer thickness.

2. The Fresnel projection screen according to claim 1, characterized in that: The target transmittance is greater than or equal to 40% and less than or equal to 60%.

3. The Fresnel projection screen according to any one of claims 1 to 2, characterized in that: The coloring layer is made by mixing the dye and a preset material, and after being made, the coloring layer is converted from a wet film state to a solidified state, and the thickness of the film layer in the wet film state is greater than the thickness of the film layer in the solidified state; The transmittance of the coloring layer is inversely proportional to the film thickness of the coloring layer.

4. The Fresnel projection screen according to claim 3, characterized in that: The film thickness of the coloring layer in a wet film state is greater than or equal to 80 μm and less than or equal to 120 μm.

5. The Fresnel projection screen according to claim 3, characterized in that: The film thickness of the coloring layer in a cured state is greater than or equal to 50 μm and less than or equal to 70 μm.

6. The Fresnel projection screen according to claim 3, characterized in that: The preset material includes UV glue; The film layer parameters also include a first mixing ratio, and the preset material is made by mixing the UV glue and the dye according to the first mixing ratio; The first mixing ratio is the mass ratio between the UV glue and the dye, and the transmittance of the coloring layer is proportional to the first mixing ratio.

7. The Fresnel projection screen according to claim 6, characterized in that: The first mixing ratio is greater than or equal to 150:1 and less than or equal to 170:

1.

8. The Fresnel projection screen according to claim 1, characterized in that: The dyes include at least red dye, blue dye and black dye; The film layer parameters also include a second mixing ratio, and the dye is prepared by mixing the red dye, the blue dye and the black dye according to the second mixing ratio; Wherein, the second mixing ratio is the mass ratio of the red dye, the blue dye and the black dye.

9. The Fresnel projection screen according to claim 8, characterized in that: The second mixing ratio is in the range of 5 to 8:4 to 6:

1.

10. The Fresnel projection screen according to claim 1, characterized in that: The coloring layer is made by mixing the dye and polyethylene terephthalate.

Images