CN210864312U - Screen structure based on Fresnel lens - Google Patents
Screen structure based on Fresnel lens Download PDFInfo
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- CN210864312U CN210864312U CN201922280852.1U CN201922280852U CN210864312U CN 210864312 U CN210864312 U CN 210864312U CN 201922280852 U CN201922280852 U CN 201922280852U CN 210864312 U CN210864312 U CN 210864312U
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Abstract
The utility model discloses a screen structure based on Fresnel lens, including Fresnel lens layer, light path adjusting layer, grating layer, the columnar microlens layer that set gradually along projection light goes out to spread, the light path adjusting layer includes at least a set of little convex lens layer, one side that little convex lens layer is close to the Fresnel lens layer corresponds and is provided with the adjusting lens layer; a plurality of light transmission holes are formed in the grating layer corresponding to the focus of the micro-convex lens layer, and an environment light absorption layer is arranged between every two adjacent light transmission holes; the utility model discloses have the beneficial effect of the colour difference that effectively reduces ambient light to projection light's influence, formation of image contrast good, effectively improve the formation of image.
Description
Technical Field
The utility model belongs to the technical field of projection equipment, concretely relates to screen structure based on fresnel lens.
Background
Most of projection screens at present need to be used under the condition of weak ambient light, so as to obtain a good projection effect. However, as the number of applications of the projection screen increases, the projection screen is used more and more in a bright environment, and because the existing imaging method has no selectivity to the ambient light, the contrast of the projection display is low under the influence of the bright ambient light, and the display effect is poor. Meanwhile, when the existing projection screen performs scattering projection, the deflection degree of blue light, green light and red light which form white light is different, and further chromatic aberration occurs during final imaging, which affects the imaging effect. Therefore, to the defect that traditional projection screen exists receive that ambient light influences great, can appear the colour difference phenomenon, the utility model discloses a screen structure based on fresnel lens.
SUMMERY OF THE UTILITY MODEL
To traditional projection screen receive the ambient light influence great, easily take place the colour difference phenomenon, the utility model aims to provide a screen structure based on fresnel lens can alleviate the ambient light to projected influence to a great extent, makes projection screen can carry out clear projection in comparatively bright environment, and the colour difference phenomenon that produces when alleviateing the projection simultaneously makes the imaging more excellent.
The utility model discloses a following technical scheme realizes:
a screen structure based on Fresnel lenses comprises a Fresnel lens layer, a light path adjusting layer, a grating layer and a columnar micro-lens layer which are sequentially arranged along the propagation direction of projection light, wherein the light path adjusting layer comprises at least one group of micro-convex lens layers, and one side of each micro-convex lens layer, which is close to the Fresnel lens layer, is correspondingly provided with an adjusting lens layer; a plurality of light transmitting holes are formed in the grating layer corresponding to the focus of the micro-convex lens layer, and an environment light absorbing layer is arranged between every two adjacent light transmitting holes.
Projection light firstly passes through the Fresnel lens layer to become parallel light outgoing under the refraction on the Fresnel lens layer, parallel light passes through the light path adjusting layer next, and the light path adjusting layer comprises at least one group of micro-convex lens layers. The micro-convex lens layer comprises a plurality of micro-convex lenses arranged in an array, parallel light rays are converged under the converging and refracting effects of the micro-convex lenses when passing through the micro-convex lenses, the converged light rays just correspond to the light holes in the grating layer and are emitted from the light holes, and then the light rays continue to enter human eyes through the columnar micro-convex lens layer. Be provided with the environment light absorption layer between the adjacent light trap on grating layer, the environment light absorption layer is obtained by the preparation of extinction material, and when external environment light shines on the environment light absorption layer through the column microlens layer, the environment light of the overwhelming majority is absorbed by the environment light absorption layer, and only few some environment light can interfere projection emergent ray, greatly reduces the influence of environment light to projection effect, can realize carrying out clear projection in comparatively bright environment.
Meanwhile, the light path adjusting layer further comprises an adjusting lens layer arranged between the micro-convex lens layer and the Fresnel lens layer, the parallel projection light is white light, and when the light passes through the micro-convex lens layer, because the wavelengths of blue light, green light and red light in the white light are different, the deflection ratios of the three color lights are different, so that the three color lights can generate a dispersion phenomenon after passing through the micro-convex lens layer, and the final projection is caused to generate chromatic aberration. In order to reduce the chromatic aberration of the projection, an adjusting lens layer is arranged between the micro-convex lens layer and the Fresnel lens layer. The adjusting lens layer can be set as an adjusting concave lens layer or an adjusting convex lens layer, if the adjusting lens layer is set as the adjusting concave lens layer, parallel light passing through the Fresnel lens layer can be diverged and refracted when passing through the adjusting concave lens layer, three color lights can also be diverged to different degrees, and then the three scattered color lights are converged through the micro-convex lens layer, so that the three emergent color lights are basically overlapped, the chromatic dispersion is compensated, and the projection chromatic aberration is reduced; if the adjusting lens layer is set as the adjusting convex lens layer, the parallel light passing through the Fresnel lens is firstly converged and refracted by the adjusting convex lens layer, the focal point of the light convergence is located between the adjusting convex lens layer and the micro-convex lens layer, the converged light is continuously diverged after the focal point convergence and converged and refracted through the micro-convex lens layer, three emergent color lights are basically overlapped, and the projection chromatic aberration is reduced.
In order to better realize the utility model discloses, furtherly, the refracting index of adjusting the lens layer is greater than the refracting index on little convex lens layer.
The refractive index of adjusting the lens layer is less than the refractive index on little convex lens layer, and the dispersion coefficient of adjusting the lens layer promptly is greater than the dispersion coefficient on little convex lens layer, consequently adjusts the lens layer and will be less than little convex lens layer to the deflection effect of light, consequently can obtain stronger the compensation of assembling through little convex lens layer through the light after adjusting the lens layer and diverge, and then makes the basic coincidence of the chromatic light of three kinds of diversions after assembling, reduces the projection chromatic aberration.
In order to better realize the utility model discloses, furtherly, laminating setting or reservation clearance setting between adjusting lens layer and the little convex lens layer.
If the adjusting lens layer is arranged as the adjusting concave lens layer, the adjusting concave lens layer and the micro-convex lens layer are arranged in a bonding mode; if adjust the lens layer and set up to adjusting the convex lens layer, then adjust and reserve the clearance setting between convex lens layer and the little convex lens layer, guarantee that parallel light passes through the focus position of adjusting after the convex lens layer assembles between adjusting convex lens layer and little convex lens layer, reserve the space and can be air bed or glass layer.
In order to better realize the utility model discloses, furtherly, adjust the regulation convex lens layer or adjust the concave lens layer of lens layer for corresponding little convex lens layer setting.
In order to better realize the utility model discloses, furtherly, the column microlens layer comprises a plurality of column lens that are the array.
The cylindrical lenses are arranged in a linear array or in a concentric circular ring array.
In order to better realize the utility model discloses, further, the lenticular lens includes circular arc column lens or triangular prism lens.
The columnar micro-lens layer is composed of a plurality of circular arc columnar lenses arranged in an array, also can be composed of a plurality of triangular prism lenses arranged in an array, and also can be composed of circular arc columnar lenses and triangular prism lenses which are alternately arranged in an array.
In order to better realize the utility model, further, the ratio of the cylinder depth to the cylinder width of the arc cylinder lens is 0.4-1.5, and the ratio of the cylinder depth to the cylinder width of the triangular prism lens is 0.4-1.5.
In order to better realize the utility model discloses, furtherly, it has dyed layer and diffusion barrier still to set gradually between nieer lens layer and the light path regulation layer.
Compared with the prior art, the utility model, following advantage and beneficial effect have:
(1) the utility model discloses a set up the grating layer to the light path that assembles that corresponds little convex lens layer on the grating layer sets up the light trap, makes the projection light after little convex lens layer assembles just through the light trap outgoing, sets up the ambient light absorption layer between adjacent light trap simultaneously, absorbs most ambient light through the ambient light absorption layer, effectively reduces the influence of ambient light to projection light, improves the contrast of formation of image; the utility model has the advantages of effectively reducing the influence of the ambient light on the projection light and having excellent imaging contrast;
(2) the utility model discloses a set up the light path regulation layer including a set of little convex lens layer at least to set up the adjusting lens layer between little convex lens layer and fresnel lens layer, after dispersing projection light in advance through the adjusting lens layer, the light that the rethread is little convex lens layer assembles the light that disperses, effectively alleviates the dispersion degree of three-color light, makes three-color light keep the state outgoing of basic coincidence, effectively reduces the chromatic aberration phenomenon of formation of image;
(3) the utility model has the advantages that the columnar micro-lens layer is arranged, the external ambient light is deflected and dispersed through the columnar micro-lens layer, so that more ambient light is absorbed by the ambient light absorption layer, and the influence of the ambient light on the projection light is further reduced;
(4) the utility model further improves the contrast and color reduction of the projection image in bright environment by arranging the Fresnel lens layer, and realizes the imaging effect of ambient light resistance and high contrast;
(5) the utility model discloses a set up the contrast and the homogeneity that dyed layer and diffusion layer improved final formation of image.
Drawings
Fig. 1 is a schematic view of an optical path in which an optical path adjusting layer is a lenticular lens layer;
FIG. 2 is a schematic view of an optical path in which the optical path adjusting layer is a concave lens layer and a picture lens layer;
FIG. 3 is a schematic structural view of the present invention;
FIG. 4 is a schematic diagram of a cylindrical microlens layer being a triangular prism lens;
fig. 5 is a schematic structural view of a colored layer and a diffusion layer.
Wherein: 1-a fresnel lens layer; 2-an optical path adjusting layer; 3-a grating layer; 4-a lenticular layer; 5-a coloring layer; 6-a diffusion layer; 21-a micro-convex lens layer; 22-accommodating the lens layer; 31-a light-transmitting hole; 32-ambient light absorbing layer.
Detailed Description
Example 1:
the fresnel lens-based screen structure of the present embodiment, as shown in fig. 1 and fig. 2, includes a fresnel lens layer 1, a light path adjusting layer 2, a grating layer 3, and a cylindrical microlens layer 4, which are sequentially arranged along a projection light propagation direction, where the light path adjusting layer 2 includes at least one group of micro-convex lens layers 21, and one side of the micro-convex lens layers 21, which is close to the fresnel lens layer 1, is correspondingly provided with an adjusting lens layer 22; a plurality of light holes 31 are formed in the grating layer 3 corresponding to the focus of the micro-convex lens layer 21, and an environmental light absorption layer 32 is arranged between adjacent light holes 31.
Projection light passes through fresnel lens layer 1 in proper order, light path adjustment layer 2, grating layer 3, get into people's eye behind the column microlens layer 4, projection light is at first through fresnel lens layer 1, projection light becomes the light outgoing that is parallel to each other under fresnel lens layer 1's refraction, then the light that is parallel to each other carries out the light path through light path adjustment layer 2 and adjusts, light path adjustment layer 2 includes a set of little convex lens layer 21 at least, little convex lens layer 21 comprises the little convex lens that a plurality of arrays set up, parallel light assembles through the bias that assembles of little convex lens, and the light after assembling just passes through the light trap 31 outgoing that corresponds the setting on grating layer 3, then emergent light gets into people's eye after the divergent extension projection range of column microlens layer 4. Be provided with environment light absorption layer 32 between the adjacent light trap 31 on grating layer 3, environment light absorption layer 32 obtains through the preparation of black extinction material, projection light passes through the light trap 31 outgoing on grating layer 3, can not be absorbed by environment light absorption layer 32, and the environment light of 4 one side incidences on the follow column microlens layer can shine on environment light absorption layer 32, most environment light is absorbed by environment light absorption layer 32, only very little partial environment light can cause the interference to projection light, finally realize effectively alleviating the influence of environment light to projection light, make projection light can carry out clear formation of image under comparatively bright environment.
Parallel light can converge and deflect when passing through the micro-convex lens layer 21 in the light path adjusting layer 2, and because the projection light comprises three color lights of blue light, green light and red light, and the wavelengths of the three color lights are different, the convergence deflection degrees of the three color lights received by the micro-convex lens layer 21 are also different, the convergence deflection degree of the blue light is strongest, the convergence deflection degree of the green light is inferior, and the convergence deflection degree of the red light is minimum, so that the three color lights which are originally coincided are mutually dispersed, and the integral imaging color is bluish when in final imaging, namely, chromatic aberration occurs. In order to reduce the degree of chromatic aberration, the optical path adjustment layer 2 further includes an adjustment lens layer 22 disposed between the micro-convex lens layer 21 and the fresnel lens layer 1, and the adjustment lens layer 22 may be configured as an adjustment concave lens layer or an adjustment convex lens layer.
If the adjusting lens layer 22 is set as the adjusting concave lens layer, the adjusting concave lens layer is composed of a plurality of adjusting concave lens arrays corresponding to the micro-convex lens layer 21, parallel light rays are firstly diverged through the adjusting concave lens layer, namely three color light rays are diverged, wherein the divergence degree of blue light is strongest, the divergence degree of green light is second to three degrees, and the divergence degree of red light is minimum, the three color light rays diverged through the adjusting concave lens layer are continuously converged through the micro-convex lens layer 21, so that the three divergent color light rays are converged to a basically coincident state, and the projection chromatic aberration is reduced.
If adjust lens layer 22 and set up to adjusting the convex lens layer, adjust the convex lens layer and constitute by the regulation convex lens array that a plurality of little convex lens layers 21 of correspondence set up, parallel light at first assembles through adjusting the convex lens layer, and the focus that light assembles is located and adjusts between convex lens layer and the little convex lens layer 21, light through assembling continues to diverge after the focus, three kinds of chromatic light take place to diverge promptly, then three kinds of chromatic light pass through little convex lens layer 21, three kinds of chromatic light assemble to the state of basic coincidence under little convex lens layer 21's effect, thereby reduce the projection chromatic aberration.
Example 2:
this embodiment is further optimized based on embodiment 1, and the refractive index of the adjusting lens layer 22 is smaller than the refractive index of the micro-convex lens layer 21.
The refractive index and the dispersion coefficient of the lens are inversely proportional, so that the refractive index of the adjusting lens layer 22 is smaller than the refractive index of the micro-convex lens layer 21, that is, the dispersion coefficient of the adjusting lens layer 22 is larger than the dispersion coefficient of the micro-convex lens layer 21, and the smaller the dispersion coefficient, the more precise and clearer the imaging is.
Because the refractive index of the adjusting lens layer 22 is smaller than that of the micro-convex lens layer 21, the divergent deflection effect of the adjusting lens layer 22 on light is weaker than the convergent deflection effect of the micro-convex lens layer 21 on light, that is, the micro-convex lens layer 21 can effectively carry out dispersion compensation on the divergent light of the adjusting lens layer 22, so that three kinds of colored light passing through the micro-convex lens layer 21 are basically restored to the coincident state, and the projection chromatic aberration is reduced.
Other parts of this embodiment are the same as embodiment 1, and thus are not described again.
Example 3:
the present embodiment is further optimized on the basis of the foregoing embodiment 1 or 2, and the adjusting lens layer 22 and the micro-convex lens layer 21 are attached or arranged with a gap.
As shown in fig. 2, the adjusting lens layer 22 is configured as an adjusting concave lens layer, and forms an adjusting concave lens and biconvex concave lens structure for adjusting the concave lens layer, then the biconvex concave lens structure for adjusting the concave lens corresponding to the micro convex lens of the micro convex lens layer 21 is configured as a biconvex lens structure, and the convex surfaces of the adjacent micro convex lenses and the concave surfaces of the adjusting concave lenses are jointed, that is, the adjusting lens layer 22 and the micro convex lens layer 21 are jointed.
As shown in fig. 1, the adjusting lens layer 22 is set as an adjusting convex lens layer, one side of the adjusting concave lens, which is close to the micro-convex lens layer 21, of the adjusting convex lens layer is a plane, one side of the adjusting concave lens, which is far away from the micro-convex lens layer 21, of the micro-convex lens structure is set, a reserved gap is set between the adjusting concave lens and the convex lens layer 21, it is ensured that a focus of parallel light rays after being converged by the adjusting concave lens is located in a gap between the adjusting concave lens and the convex lens layer 21, namely, the reserved gap is set between the adjusting lens layer 22 and the micro-convex lens layer 21, and the reserved gap can be set as an air.
The rest of this embodiment is the same as embodiment 1 or 2, and therefore, the description thereof is omitted.
Example 4:
this embodiment is further optimized based on any one of embodiments 1 to 3, and the adjusting lens layer 22 is an adjusting convex lens layer or an adjusting concave lens layer disposed corresponding to the micro-convex lens layer 21.
Other parts of this embodiment are the same as any of embodiments 1 to 3, and thus are not described again.
Example 5:
this embodiment is further optimized on the basis of any one of embodiments 1 to 4, where the lenticular lens layer 4 is formed by a plurality of lenticular lenses arranged in an array, and adjacent lenticular lenses are closely attached to each other.
The cylindrical microlens layer 4 is composed of a plurality of cylindrical lenses in a linear array, or the cylindrical microlens layer 4 is composed of a plurality of cylindrical lenses in a concentric ring array, and the adjacent cylindrical lenses are arranged in a mutual clinging manner.
Other parts of this embodiment are the same as any of embodiments 1 to 4, and thus are not described again.
Example 6:
this embodiment is further optimized based on any one of embodiments 1 to 5 above, and the lenticular lens includes a circular arc lenticular lens or a triangular prism lenticular lens.
As shown in fig. 2, the lenticular microlens layer 4 is formed by a plurality of circular cylindrical lens arrays, and adjacent circular cylindrical lenses are closely attached to each other.
As shown in fig. 4, the lenticular microlens layer 4 is formed by a plurality of triangular prism lens arrays, and adjacent triangular prism lenses are closely attached.
As shown in fig. 3, the circular arc cylindrical lenses and the triangular prism lenses alternately arranged constitute one array unit, and the lenticular lens layer 4 is constituted by a plurality of array units arranged in an array.
Other parts of this embodiment are the same as any of embodiments 1 to 5, and thus are not described again.
Example 7:
this embodiment is further optimized on the basis of any one of embodiments 1 to 6, in which the ratio of the cylinder depth to the cylinder width of the arc-shaped cylindrical lens is 0.4 to 1.5, and the ratio of the cylinder depth to the cylinder width of the triangular-prism lens is 0.4 to 1.5.
The ratio of the depth to the width of the cylindrical surface of the arc-shaped cylindrical lens is set to be 0.4-1.5, and the ratio of the depth to the width of the cylindrical surface of the triangular-prism lens is set to be 0.4-1.5, so that light can show more brightness uniformity after passing through the arc-shaped cylindrical lens or the triangular-prism lens, and the imaging effect is improved.
Other parts of this embodiment are the same as any of embodiments 1 to 6, and thus are not described again.
Example 8:
this embodiment is further optimized on the basis of any of embodiments 1 to 7, and as shown in fig. 5, a coloring layer 5 and a diffusion layer 6 are further sequentially disposed between the fresnel lens layer 1 and the optical path adjusting layer 2.
The coloring layer 5 and the diffusion layer 6 are made of high transmittance resin with transmittance of more than 90% and uniformly added with pigment and diffusion particles, so that the contrast of the screen can be improved and the brightness uniformity is better.
Other parts of this embodiment are the same as any of embodiments 1 to 7, and thus are not described again.
The above is only the preferred embodiment of the present invention, not to the limitation of the present invention in any form, all the technical matters of the present invention all fall into the protection scope of the present invention to any simple modification and equivalent change of the above embodiments.
Claims (8)
1. A screen structure based on Fresnel lenses is characterized by comprising a Fresnel lens layer (1), a light path adjusting layer (2), a grating layer (3) and a columnar micro-lens layer (4) which are sequentially arranged along the propagation direction of projection light, wherein the light path adjusting layer (2) comprises at least one group of micro-convex lens layers (21), and one side, close to the Fresnel lens layer (1), of each micro-convex lens layer (21) is correspondingly provided with an adjusting lens layer (22); a plurality of light holes (31) are formed in the grating layer (3) corresponding to the focus of the micro-convex lens layer (21), and an environment light absorption layer (32) is arranged between every two adjacent light holes (31).
2. Fresnel lens-based screen structure according to claim 1, characterised in that the refractive index of the adjusting lens layer (22) is smaller than the refractive index of the lenticular lens layer (21).
3. Fresnel lens based screen structure according to claim 2, characterized in that the adjusting lens layer (22) and the micro-convex lens layer (21) are arranged in a joint manner or with a gap.
4. Fresnel lens based screen structure according to claim 3, characterized in that said adjusting lens layer (22) is an adjusting convex lens layer or an adjusting concave lens layer arranged in correspondence of the micro-convex lens layer (21).
5. Fresnel lens based screen structure according to the previous claims 1-4, characterized by that the lenticular lens layer (4) is composed of a plurality of lenticular lenses arranged in an array.
6. A Fresnel lens based screen structure according to claim 5, wherein said lenticular lenses comprise circular arc cylindrical lenses or triangular prism lenses.
7. A Fresnel lens based screen structure according to claim 6, wherein said arc cylinder lens has a cylinder depth to cylinder width ratio of 0.4-1.5, and said triangular cylinder lens has a cylinder depth to cylinder width ratio of 0.4-1.5.
8. A fresnel lens-based screen structure according to claim 1, characterized in that a coloring layer (5) and a diffusion layer (6) are further disposed between the fresnel lens layer (1) and the optical path adjusting layer (2) in sequence.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922280852.1U CN210864312U (en) | 2019-12-18 | 2019-12-18 | Screen structure based on Fresnel lens |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922280852.1U CN210864312U (en) | 2019-12-18 | 2019-12-18 | Screen structure based on Fresnel lens |
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| Publication Number | Publication Date |
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| CN210864312U true CN210864312U (en) | 2020-06-26 |
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| CN201922280852.1U Active CN210864312U (en) | 2019-12-18 | 2019-12-18 | Screen structure based on Fresnel lens |
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| CN (1) | CN210864312U (en) |
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- 2019-12-18 CN CN201922280852.1U patent/CN210864312U/en active Active
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