CN114114507A - Polarization-maintaining optical film, interference-relieving polarization-maintaining micro-lens film and preparation method thereof - Google Patents

Polarization-maintaining optical film, interference-relieving polarization-maintaining micro-lens film and preparation method thereof Download PDF

Info

Publication number
CN114114507A
CN114114507A CN202111010655.3A CN202111010655A CN114114507A CN 114114507 A CN114114507 A CN 114114507A CN 202111010655 A CN202111010655 A CN 202111010655A CN 114114507 A CN114114507 A CN 114114507A
Authority
CN
China
Prior art keywords
polarization
layer
maintaining
film
micro
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202111010655.3A
Other languages
Chinese (zh)
Other versions
CN114114507B (en
Inventor
夏寅
余洋
赵国林
付坤
陈建文
李刚
唐海江
张彦
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ningbo Exciton Technology Co Ltd
Original Assignee
Ningbo Exciton Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ningbo Exciton Technology Co Ltd filed Critical Ningbo Exciton Technology Co Ltd
Publication of CN114114507A publication Critical patent/CN114114507A/en
Application granted granted Critical
Publication of CN114114507B publication Critical patent/CN114114507B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements
    • G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
    • G02B5/3033—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid
    • G02B5/3041—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid comprising multiple thin layers, e.g. multilayer stacks
    • G02B5/305—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid comprising multiple thin layers, e.g. multilayer stacks including organic materials, e.g. polymeric layers
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/0006—Arrays
    • G02B3/0012—Arrays characterised by the manufacturing method
    • G02B3/0031—Replication or moulding, e.g. hot embossing, UV-casting, injection moulding
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/0006—Arrays
    • G02B3/0037—Arrays characterized by the distribution or form of lenses
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133606—Direct backlight including a specially adapted diffusing, scattering or light controlling members
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133606—Direct backlight including a specially adapted diffusing, scattering or light controlling members
    • G02F1/133607—Direct backlight including a specially adapted diffusing, scattering or light controlling members the light controlling member including light directing or refracting elements, e.g. prisms or lenses
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
    • Y02A90/10—Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Nonlinear Science (AREA)
  • Mathematical Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Polarising Elements (AREA)

Abstract

The invention relates to a polarization-maintaining optical film, in particular to a polarization-maintaining optical film applied to an LCD linear polarization backlight source, an interference-relieving polarization-maintaining micro-lens film and a preparation method thereof. The invention provides a de-interference polarization-maintaining micro-lens film and a preparation method thereof, aiming at solving the problem that the optical film in the traditional backlight can generate depolarization in the polarization light source synergy scheme. The polarization-maintaining micro-lens film comprises a polarization-maintaining base layer, a first structural layer and a second structural layer, wherein the first structural layer is a randomly-arranged micro-lens array layer and is positioned on the upper surface of the base layer, and the second structural layer is not present or is an atomizing layer and is positioned on the lower surface of the base layer. In the randomly arranged microlens array layer, the coordinates of the main optical axes of three adjacent microlenses are connected to form a common triangle, and the distance between the main optical axes of the adjacent microlenses randomly changes within a certain value range. The polarization degree of incident light can be kept high when linearly polarized light in the LCD backlight passes through the polarization-maintaining micro-lens film.

Description

Polarization-maintaining optical film, interference-relieving polarization-maintaining micro-lens film and preparation method thereof
Technical Field
The invention relates to a polarization-maintaining micro-lens film, in particular to a polarization-maintaining optical film applied to an LCD linear polarization backlight source, an interference-relieving polarization-maintaining micro-lens film and a preparation method thereof.
Background
In the conventional Liquid Crystal Display (LCD) field, the display of the LCD panel requires a backlight module to provide a light source for the LCD panel, and the LED point light source can be converted into a uniform planar light source through various optical films and light guide plates in the backlight module. However, the light energy of the planar light source is actually very inefficient for the liquid crystal panel.
One reason for this is that the transmittance of the lower polarizer (13) of the liquid crystal panel is only 40% (as shown in table 1). Since the conversion efficiency from point light source to surface light source is greatly different due to different backlight designs (direct or side-in type), the light energy attenuation process of the traditional liquid crystal display panel to the backlight source is discussed by taking the surface light source as a 100% standard. It can be seen that the loss is the most (about 70%) when passing through the optical filter, because the white light is filtered to remove the other two colors to generate RGB monochromatic light, and secondly, the loss is relatively serious (about 60%) when passing through the lower polarizer initially, because the ordinary light source forms linear polarization, and needs to go through the dichroic absorption process of the PVA layer, only the linear polarization (22) with the polarization direction parallel to the transmission axis of the polarizer is retained, and the linear polarization (22) in the vertical direction is absorbed, as shown in fig. 1, the light emitted from the backlight module (14) is partial polarization (21), the linear polarization (22) in the parallel direction is smoothly transmitted after the partial polarization (21) passes through the lower polarizer (13), the linear polarization (23) in the vertical direction is absorbed by the lower polarizer (13), and the linear polarization in the parallel direction is twisted by the liquid crystal and changes the polarization direction when passing through the liquid crystal panel (12), and is transformed into the linear polarization (23) in the vertical direction and smoothly transmitted through the upper polarizer (11), the emitted light is finally linearly polarized light (23) in the vertical direction.
Table 1 light energy attenuation process of conventional lcd panel to backlight
Investigation sequence Attenuation position Cause of attenuation Transmittance of light Residual light energy
6 Cover plate Surface reflection 90％ 9.2％
5 Upper polarizer Surface reflection 90％ 10.3％
4 Optical filter Wavelength cut-off and absorption 30％ 11.4％
3 Liquid crystal layer Transmission of polarized light 95％ 38％
2 Lower polarizer Surface reflection and polarization 40％ 40％
1 Area light source Backlight material light distribution conversion / 100％
0 Point light source / / /
If the polarized light of the backlight surface light source is polarized before entering the polarized light, the polarized light is converted into linearly polarized light parallel to the backlight surface light source, so that the transmittance of the polarized light to the backlight surface light source is greatly improved, the utilization rate of the whole liquid crystal panel to the surface light source is greatly improved, the brightness of the display is improved, and the electricity and the energy are saved.
The traditional synergy scheme is back-end polarization, that is, a reflection type polarizer (RP) (15) adopting a multilayer film system design is added to the original backlight framework: the reflection type polarizer (15) can transmit the completely polarized P light and reflect the S light; the S light can emit depolarized light in the backlight system to reform partial polarized light; part of the polarized light is repeatedly transmitted from the RP to generate more P light; circulating for many times until the energy is exhausted; the increased P light can increase the light energy utilization rate by 20-30% compared with the original structure. As shown in fig. 2, the light emitted from the backlight module (14) is partially polarized light (21), the partially polarized light (21) enters the reflective polarizer (15), and the reflective polarizer (15) can transmit linearly polarized light (22) in the parallel direction and reflect linearly polarized light (23) in the perpendicular direction; linearly polarized light (23) in the vertical direction can be depolarized in the backlight system to form partially polarized light (21) again; after the linearly polarized light (22) in the parallel direction passes through the lower polarizer (13), the linearly polarized light (22) in the parallel direction smoothly transmits, no linearly polarized light (23) in the vertical direction is absorbed at the moment, the linearly polarized light in the parallel direction is twisted by liquid crystal when passing through the liquid crystal panel (12), the polarization direction is changed, the linearly polarized light (23) in the vertical direction is converted into the linearly polarized light (23) in the vertical direction and smoothly transmits from the upper polarizer (11), and emergent light is finally the linearly polarized light (23) in the vertical direction.
However, the reflective polarizer is very expensive due to its complicated equipment and process, and low supply resources. Therefore, there is a need to propose new synergistic solutions.
Another feasible scheme is front-end polarization, namely a backlight module adopts a linear polarization point light source to emit linearly polarized light from the beginning, and the direction of the polarized light is consistent with the transmission axis of the lower polarizer (13). As shown in fig. 3, the light emitted by the backlight module (14) is linearly polarized light (22) in the parallel direction, after the linearly polarized light (22) passes through the lower polarizer (13), the linearly polarized light (22) in the parallel direction smoothly transmits, when the linearly polarized light passes through the liquid crystal panel (12), the linearly polarized light is twisted by the liquid crystal and changes the polarization direction, the linearly polarized light is converted into linearly polarized light (23) in the vertical direction and smoothly transmits from the upper polarizer (11), and the emergent light is finally linearly polarized light (23) in the vertical direction. However, in the process of converting the linear polarization point light source into the surface light source, because the conventional optical film has optical anisotropy and a very low polarization maintaining degree (completely polarized light is incident and is subjected to more or less depolarization through the optical film, the polarization degree of the emergent light is reduced, partial polarized light is generated, the polarization maintaining degree, which is the ratio of the polarization degree of the emergent light to the polarization degree of the incident light, is also expressed by the polarization degree of the emergent light because the polarization degree of the incident light is 1, generally between 50% and 70%, and finally the polarization degree of the surface light source is rapidly reduced, and a significant depolarization phenomenon is generated, while the partial polarized light is still filtered by the lower polarizer to a large extent, and the expected synergy is not achieved, as shown in fig. 4, after linearly polarized light (22) in the parallel direction passes through the conventional optical film (3), the emergent light is partially polarized light (21), and after the partially polarized light (21) passes through the lower polarizer (13), linearly polarized light (22) in the parallel direction smoothly transmits, linearly polarized light (23) in the vertical direction is absorbed by the lower polarizer (13), the linearly polarized light in the parallel direction is twisted by liquid crystal when passing through the liquid crystal panel (12), the polarization direction is changed, the linearly polarized light (23) in the vertical direction is converted into the linearly polarized light (23) in the vertical direction and smoothly transmits from the upper polarizer (11), and emergent light is finally the linearly polarized light (23) in the vertical direction.
Disclosure of Invention
The invention provides a polarization-maintaining optical film and a preparation method thereof, aiming at solving the problem that the optical film in the traditional backlight can generate a serious depolarization phenomenon in a polarization light source synergy scheme. The polarization-maintaining optical film provided by the invention has higher polarization maintaining degree for incident linearly polarized light, and the polarization-removing phenomenon is reduced.
In order to solve the technical problems, the invention adopts the following technical scheme:
the invention provides a polarization-maintaining optical film which comprises a polarization-maintaining base layer, a first structural layer and/or a second structural layer, wherein the first structural layer is positioned on the upper surface of the polarization-maintaining base layer, and the second structural layer is positioned on the lower surface of the polarization-maintaining base layer.
When linearly polarized light passes through the polarization-maintaining optical film, the polarization-maintaining optical film has a polarization maintaining degree of greater than or equal to 80% for incident linearly polarized light.
Further, when linearly polarized light in the LCD backlight passes through the polarization maintaining optical film, the polarized incident light may retain a higher polarization degree, and the polarization maintaining degree is greater than or equal to 80%. Thereby ensuring the final high transmission of the polarizer under the LCD and greatly improving the utilization rate of the backlight source.
The optical film in the conventional backlight refers to an existing diffusion film, microlens film, prism film, or inverse prism film.
The polarization-maintaining optical film is one of a polarization-maintaining diffusion film, a polarization-maintaining micro-lens film, a polarization-maintaining prism film and a polarization-maintaining inverse prism film.
The polarization-maintaining optical film provided by the invention is an improvement of the existing optical film, and the material of a base layer (also called a supporting layer) of the existing optical film is changed into a material with high polarization-maintaining degree to linearly polarized light.
The polarization maintaining matrix layer has a polarization maintaining degree of more than 99%.
The polarization-maintaining matrix layer is made of optically isotropic transparent polymer.
The thickness T of the polarization-maintaining matrix layer is 25-250 mu m.
The material of the polarization-maintaining matrix layer is selected from one or the combination of at least two of polymethyl methacrylate (PMMA), Polycarbonate (PC), Triacetylcellulose (TAC) and Cyclic Olefin Polymer (COP).
The haze of the polarization-maintaining diffusion film is 60-98%.
The first structural layer of the polarization-maintaining diffusion film is an atomized layer, the second structural layer does not exist or is the atomized layer, and the atomized layer is selected from a non-particle coating or a particle coating.
The haze of the first atomized layer/the second atomized layer is 5-98%.
The particle-free coating of the polarization-maintaining diffusion film is composed of a transparent polymer resin. The particle-coated layer is composed of a transparent polymer resin and transparent polymer particles; the particle diameter of the transparent polymer particles is 1 to 20 μm.
The haze of the polarization-maintaining micro-lens film is 60-98%.
The first structural layer of the polarization-maintaining micro-lens film is a micro-lens array layer; in the microlens array layer, the coordinates of the main optical axes of three adjacent microlenses are connected to form a regular triangle, or the coordinates of the main optical axes of four adjacent microlenses are connected to form a square; the microlenses in the microlens array are closely arranged.
The haze of the micro-lens array layer is 60-98%.
In the microlens array layer, the distance D between the main optical axes of adjacent microlenses is 10-50 μm, the width of each microlens is W (W ═ D), the height of each microlens is H, and the aspect ratio H/W is 0.05-0.5.
The first structural layer of the polarization-maintaining prism film is a prism layer, and the second structural layer is absent or is an atomized layer; the prism layer is formed by tiling prism ribs, the cross sections of the prism ribs are isosceles triangles, the bottom edges of the triangles are 10-100 mu m, and the vertex angles are 75-105 degrees; the haze of the atomization layer is 0-30%.
The second structural layer of the polarization-maintaining inverse prism film is an inverse prism layer, and the first structural layer does not exist or is an atomized layer; the inverted prism layer is formed by tiling triangular prism ribs, the cross sections of the triangular prism ribs are isosceles triangles or common triangles, the width L of the bottom side of each triangle is 10-100 mu m, the vertex angle theta is selected from 40-80 degrees, preferably 60 degrees, one larger bottom angle alpha is 90-0.5 theta + gamma, gamma is 0-10 degrees, when gamma is 0 degree, the cross section is isosceles triangle, and when gamma is more than 0 degree, the cross section is common triangle. The haze of the atomization layer is 0-60%.
The material of the atomizing layer is selected from one of AR (Acrylic resin or modified Acrylic resin), PMMA, PC or Polyurethane (PU). AR is preferably a photo-curing process, PMMA, PC are preferably a hot-pressing process, and PU is preferably a thermal-curing process.
When the atomized layer is a particle coating, the refractive index na of the transparent polymer resin is selected from 1.4-1.65. When the atomized layer is a particle-free coating, the refractive index nb of the transparent polymer resin is selected from 1.4-1.65.
The transparent polymer particles are selected from one or a combination of at least two of PMMA, PBMA (polybutylmethacrylate), PS (polystyrene), PU (polyurethane) and organosilicon.
The microlens array layer is formed by transparent polymer resin, and the material of the transparent polymer resin is selected from one of AR, PMMA or PC. AR is preferably a photo-curing process, and PMMA, PC are preferably a hot-pressing process. The refractive index nc of the transparent polymer resin of the micro-lens array layer is selected from 1.4-1.65.
The prism layer is made of transparent polymer resin, and the material of the transparent polymer resin is selected from one of AR, PMMA and PC. AR is preferably a photo-curing process, and PMMA, PC are preferably a hot-pressing process. The refractive index nd of the transparent polymer resin is selected from 1.5-1.65.
The reverse prism layer is made of transparent polymer resin, and the material of the transparent polymer resin is selected from one of AR, PMMA and PC. AR is preferably a photo-curing process, and PMMA, PC are preferably a hot-pressing process. The refractive index ne of the transparent polymer resin of the prism layer is selected from 1.5-1.65.
Further, in the polarization-maintaining diffusion film provided by the invention, the first structural layer is an atomized layer dl (diffusion layer), and the second structural layer is not present. The thickness T of the substrate layer is 50-250 μm, the polarization-maintaining substrate layer is made of PC, TAC, PMMA or COP, the optical isotropy is realized, the polarization maintaining degree is greater than 99%, and the haze of the polarization-maintaining diffusion film is 98%. The haze of the first atomization layer is 98%, the type of the atomization layer is a particle coating, the transparent polymer resin is selected from PU or AR, the transparent polymer particles are PMMA, PS, organic silicon or PU, the particle size d is 5-15 mu m or 8-20 mu m, and the refractive index na of the transparent polymer resin is 1.4, 1.5 or 1.65. The polarization-maintaining diffusion film has a polarization maintaining degree of 81-83% (e.g., 81%, 82%, or 83%).
The first structural layer is an atomized layer DL (diffusion layer), and the second structural layer does not exist. The thickness T of the substrate layer is 250 mu m, the polarization-maintaining substrate layer is made of PC, the optical isotropy is realized, the polarization maintaining degree is greater than 99%, and the haze of the polarization-maintaining diffusion film is 98%. The haze of the first matte layer is 98%, the type of the matte layer is a particle-free coating, the transparent polymer resin is PC, and the refractive index na of the transparent polymer resin is 1.5. The polarization maintaining diffusion film has a polarization maintaining degree of 83%.
According to the polarization-maintaining diffusion film provided by the invention, the first structural layer is an atomized layer, and the second structural layer is an atomized layer. The thickness T of the matrix layer is 50-250 μm (for example, 25 μm, 50 μm, 100 μm, 125 μm, 250 μm), the polarization-maintaining matrix layer is made of PC or PMMA, the optical isotropy is realized, the polarization maintaining degree is greater than 99%, and the haze of the polarization-maintaining diffusion film is 60-98% (for example, 60%, 80%, 90%, 95% or 98%). The haze of the first atomization layer is 98%, the type of the atomization layer is a particle coating, the transparent polymer resin is PU or AR, the transparent polymer particles are PMMA, the particle size d is 5-15 mu m, and the refractive index na of the transparent polymer resin is 1.5 or 1.65. The haze of the second atomization layer is 5%, the type of the second atomization layer is a particle coating, the transparent polymer resin is AR, the transparent polymer particles are PMMA, the particle size d is 1-3 micrometers or 5-15 micrometers, and the refractive index na of the transparent polymer resin is 1.5.
According to the polarization-maintaining diffusion film provided by the invention, the first structural layer is an atomized layer, and the second structural layer is an atomized layer. The thickness T of the substrate layer is 250 mu m, the polarization-maintaining substrate layer is made of PC, the optical isotropy is realized, the polarization maintaining degree is greater than 99%, and the haze of the polarization-maintaining diffusion film is 98%. The haze of the first atomization layer is 98%, the type of the atomization layer is a particle coating, the transparent polymer resin is PU or AR, the transparent polymer particles are PMMA, the particle size d is 5-15 mu m, and the refractive index na of the transparent polymer resin is 1.5 or 1.65. The haze of the second matte layer is 5%, the matte layer is a particle-free coating and is composed of a transparent polymer resin AR, and the refractive index nb of the transparent polymer resin is 1.5 or 1.6. The polarization maintaining diffusion film has a polarization maintaining degree of 80%.
Further, the invention provides a polarization-maintaining microlens film, wherein the first structural layer is a microlens array layer ml (microlens layer), and the second structural layer is not present. The thickness T of the matrix layer is 25-250 μm (for example, 25 μm, 50 μm, 100 μm, 125 μm, 250 μm), the material of the polarization-maintaining matrix layer is selected from PC or PMMA, the optical isotropy is realized, the polarization maintaining degree is > 99%, and the haze of the polarization-maintaining micro-lens film is 60-98% (for example, 60%, 70%, 85%, 92%, 96%, 98%). The microlens array layer has a haze of 98%, and is formed of a transparent polymer resin AR or PC having a refractive index nc of 1.4-1.65 (e.g., 1.4, 1.5, 1.65). In the microlens array layer, the distance D between the main optical axes of adjacent microlenses is 10 μm to 50 μm (for example, 10 μm, 20 μm, 35 μm, 50 μm), the width of a microlens is W (W ═ D), the height of a microlens is H, and the aspect ratio H/W is 0.05 to 0.5 (for example, 0.05, 0.1, 0.2, 0.5); the polarization maintaining micro lens has a polarization maintaining degree of 80% -97% (e.g. 80%, 85%, 88%, 90%, 95%, 97%).
The invention provides a polarization-maintaining micro-lens film, wherein a first structural layer is a micro-lens array layer, and a second structural layer is an atomizing layer. The thickness T of the substrate layer is 250 mu m, the polarization-maintaining substrate layer is made of PC (polycarbonate), the optical isotropy is realized, the polarization maintaining degree is greater than 99%, and the haze of the polarization-maintaining micro-lens film is 96%. The haze of the microlens array layer is 98%, the microlens array layer is composed of a transparent polymer resin AR, and the refractive index nc of the transparent polymer resin is 1.5. In the microlens array layer, the pitch D of the main optical axes of adjacent microlenses is 50 μm, the width of a microlens is W (W ═ D), the height of a microlens is H, and the aspect ratio H/W is 0.5. The haze of the atomization layer is 5%, the type of the atomization layer is a particle-free coating and is composed of a transparent polymer AR, and the refractive index nb of the transparent polymer resin is 1.5. The polarization maintaining micro-lens film has 85% polarization maintaining degree.
The invention provides a polarization-maintaining micro-lens film, wherein a first structural layer is a micro-lens array layer, and a second structural layer is an atomizing layer. The thickness T of the substrate layer is 100 mu m, the polarization-maintaining substrate layer is made of TAC, PMMA or COP, the optical isotropy is realized, the polarization maintaining degree is greater than 99%, and the haze of the polarization-maintaining micro-lens film is 96%. The haze of the microlens array layer is 98%, the microlens array layer is formed of a transparent polymer resin AR or PMMA, and the refractive index nc of the transparent polymer resin is 1.5. In the microlens array layer, the pitch D of the main optical axes of adjacent microlenses is 50 μm, the width of a microlens is W (W ═ D), the height of a microlens is H, and the aspect ratio H/W is 0.5. The haze of the atomization layer is 5%, the type of the atomization layer is a particle coating and is composed of transparent polymer resin AR and transparent polymer resin particles PMMA, the refractive index nb of the transparent polymer resin is 1.5, and the particle size of the polymer resin particles PMMA is 3-5 microns. The polarization maintaining micro-lens film has 85% polarization maintaining degree.
Further, the present invention provides a polarization maintaining prism film, wherein the first structural layer is a prism layer pl (prism layer), and the second structural layer is absent. The thickness T of the matrix layer is 25-250 μm (for example, 25 μm, 50 μm, 100 μm, 125 μm, 250 μm), the polarization-maintaining matrix layer is made of PC, TAC, PMMA or COP, the prism layer is made of transparent polymer resin AR, PMMA or PC, and the refractive index nd of the transparent polymer resin is 1.5-1.65 (for example, 1.5, 1.55 or 1.65). The prism layer is formed by tiling triangular prism ribs, the cross sections of the triangular prism ribs are isosceles triangles, the bottom edges of the triangles are 10-100 mu m (such as 10-20 mu m, 50 mu m and 100 mu m), and the vertex angles are 75-105 degrees (such as 75 degrees, 90 degrees and 105 degrees). The polarization maintaining degree of the polarization maintaining prism film is 98%.
The invention provides a polarization maintaining prism film, wherein a first structural layer is a prism layer PL (prism layer), and a second structural layer is an atomized layer. The thickness T of the substrate layer is 250 mu m, the polarization-maintaining substrate layer is made of PC (polycarbonate), the optical isotropy is realized, the polarization maintaining degree is more than 99%, the prism layer is made of transparent polymer resin AR, and the refractive index nd of the transparent polymer resin is 1.55. The prism layer is formed by tiling triangular prism ribs, the cross sections of the triangular prism ribs are isosceles triangles, the bottom sides of the triangles are 50 micrometers, and the vertex angles are 90 degrees. The haze of the atomization layer is 5% -30%, the type of the atomization layer is a particle-free coating and is composed of a transparent polymer AR, and the refractive index nb of the transparent polymer resin is 1.5. The polarization maintaining degree of the polarization maintaining prism film is 95% -97%.
Further, the present invention provides a polarization maintaining inverse prism film, wherein the first structural layer is absent, and the second structural layer is an inverse prism layer RL (reverse-prism layer). The thickness T of the matrix layer is 25-250 μm, the polarization-maintaining matrix layer is made of PC, TAC, PMMA or COP, the optical isotropy is realized, the polarization maintaining degree is greater than 99%, the reverse prism layer is made of a transparent polymer resin AR, PC or PMMA, and the refractive index nd of the transparent polymer resin is 1.5-1.65 (such as 1.5, 1.55 or 1.65). The inverted prism layer is formed by tiling triangular prism ribs, the cross sections of the triangular prism ribs are isosceles triangles or common triangles, the width L of the bottom edge of each triangle is 10-100 mu m (such as 10-20 mu m, 50-100 mu m), the vertex angle theta is selected from 40-90 degrees (such as 40 degrees, 60 degrees, 80 degrees or 90 degrees), one larger bottom angle alpha is 90-0.5 theta + gamma, and the deflection angle gamma is 0-10 degrees. The polarization maintaining degree of the polarization maintaining inverse prism film is 98%.
The invention provides a polarization-maintaining inverse prism film, wherein a first structural layer is an atomized layer, and a second structural layer is an inverse prism layer RL (reverse-prism layer). The thickness T of the substrate layer is 250 mu m, the polarization-maintaining substrate layer is made of PC (polycarbonate), the optical isotropy is realized, the polarization maintaining degree is more than 99%, the inverse prism layer is made of a transparent polymer resin AR, and the refractive index nd of the transparent polymer resin is 1.55. The inverted prism layer is formed by tiling triangular prism ribs, the cross sections of the triangular prism ribs are isosceles triangles, the width L of the bottom edge of each triangle is 50 mu m, the vertex angle theta is selected from 60 degrees, one larger bottom angle alpha is 90-0.5 theta + gamma, and the deflection angle gamma is 0 deg. The haze of the atomization layer is 30% -60%, the type of the atomization layer is a particle-free coating and is composed of a transparent polymer AR, and the refractive index nb of the transparent polymer resin is 1.5. The polarization maintaining degree of the polarization maintaining prism film is 90% -95%.
The invention also provides a preparation method of the polarization-maintaining optical film, wherein the resin or the resin formula containing particles is respectively prepared into a first structural layer or a second structural layer on the front surface/the back surface of the polarization-maintaining matrix layer by sequentially utilizing the processes of coating, micro-replication or hot press molding; the coating is suitable for preparing an atomizing layer of a polarization-maintaining diffusion film, and the micro-replication and hot press molding are suitable for preparing the atomizing layer, the micro-lens layer and the prism layer of the polarization-maintaining diffusion film, the polarization-maintaining micro-lens film, the polarization-maintaining prism film and the polarization-maintaining inverse prism film.
Further, the preparation method of the polarization-maintaining optical film comprises the following steps:
(1) coating a first structural layer on the front surface of the polarization-maintaining base layer serving as a supporting layer to obtain a polarization-maintaining optical film containing the first structural layer;
further, the preparation method of the polarization-maintaining optical film comprises the following steps:
(1) a mold roll (roll 1) for producing a first structural layer;
(2) using the polarization-maintaining matrix layer as a supporting layer, and performing micro-replication or hot-press molding on the front surface by using a roller 1 to obtain a first structural layer (convex) to obtain a polarization-maintaining optical film containing the first structural layer;
further, the preparation method of the polarization-maintaining optical film comprises the following steps:
(1) taking the polarization-maintaining matrix layer as a supporting layer, and coating a second structural layer on the back surface to obtain a polarization-maintaining optical film containing the second structural layer;
further, the preparation method of the polarization-maintaining optical film comprises the following steps:
(1) preparing a mould roller (roller 2) of the second structural layer;
(2) taking the polarization-maintaining matrix layer as a supporting layer, and utilizing a roller 2 to micro-copy or hot-press molding a second structural layer on the back surface to obtain a polarization-maintaining optical film containing the second structural layer; (ii) a
Further, the preparation method of the polarization-maintaining optical film comprises the following steps:
(1) coating a first structural layer on the front surface of the polarization-maintaining base layer serving as a supporting layer to obtain a semi-finished product containing the first structural layer;
(2) coating a second structural layer on the back of the semi-finished product prepared in the step (1) to obtain a polarization maintaining optical film simultaneously containing the first structural layer and the second structural layer;
further, the preparation method of the polarization-maintaining optical film comprises the following steps:
(1) a mold roll (roll 1) for producing a first structural layer;
(2) utilizing a mold roller to micro-copy or hot-press and form a first structural layer on the front surface of the polarization-preserving matrix layer to obtain a semi-finished product containing the first structural layer;
(3) preparing a mould roller (roller 2) of the second structural layer;
(4) utilizing a roller 2 to micro-copy or hot-press and form a second structural layer on the back of the polarization-maintaining matrix layer to obtain a polarization-maintaining optical film simultaneously containing the first structural layer and the second structural layer;
it should be noted that the processing manner of the first structural layer and the second structural layer should be selected according to the type of the structural layer and the type of the material, and the invention is not preferred;
it should be noted that the method for preparing the polarization-maintaining optical film provided by the invention is suitable for the production of sheets and is also suitable for the production of coiled materials.
The polarization-maintaining optical film can be used as an optical functional material for an optical system needing polarization maintaining. The polarization maintaining optical film is particularly suitable for an LCD linear polarization backlight source, and can maintain higher polarization degree when linearly polarized light in the backlight passes through the polarization maintaining optical film, so that the final high transmittance of a polarizer under the LCD is ensured, and the utilization rate of the backlight source is greatly improved.
Compared with the prior art, the polarization-maintaining optical film provided by the invention can be matched with a linear polarization point light source, a linear polarization backlight source can be conveniently generated, a reflection-type polarizer with complex process and high price is not needed, the high transmittance of the polarizer under an LCD can be ensured, the utilization rate of the backlight source is improved, the cost performance of a synergistic scheme is higher, and the advantages are obvious.
In order to further improve the polarization maintaining performance of a complex backlight structure with multiple stacked films, the polarization maintaining performance of each polarization maintaining optical film needs to be improved as much as possible, otherwise, the polarization maintaining performance of the complex backlight structure is obviously reduced. On the premise of not losing the original optical function of the polarization-maintaining optical film, the invention provides a further optimization scheme for improving the polarization-maintaining performance of a single membrane to adapt to a complex backlight framework.
Research finds that although the microlens film is generally high in haze and has a diffusion-like light uniformizing effect, the microlens film is placed above the prisms to help to eliminate interference between the prisms and the panel, then the microlens array of the traditional microlens film is regularly arranged, and each microlens is of the same structure, so that the microlens film is prone to generate interference with the panel with high resolution, and corner cutting is needed.
In order to solve the interference problem of the microlens film, it is necessary to develop a de-interference microlens film, which changes the regular arrangement into the random arrangement. And in order to balance the light uniformizing effect and the polarization maintaining performance of the polarization maintaining microlens film, the coverage rate and the aspect ratio thereof need to be further defined.
The invention provides a de-interference polarization-maintaining micro-lens film, which comprises a polarization-maintaining base layer, a first structural layer and a second structural layer; the first structural layer is a randomly arranged micro-lens array layer and is positioned on the upper surface of the substrate layer; the second structural layer is not present or is an atomizing layer and is positioned on the lower surface of the substrate layer.
In the randomly arranged microlens array layer, the coordinates of the main optical axes of three adjacent microlenses are connected to form a common triangle, and the distance D between the main optical axes of the adjacent microlenses randomly changes within a certain value range. The common triangle refers to a triangle except for a right-angled triangle, an isosceles triangle and an equilateral triangle.
In the randomly arranged microlens array layer, the width W (aperture) of the microlenses is a constant value.
In the random arrangement microlens array layer, the aspect ratio B (B ═ H/W) of the microlenses is a constant value.
In the random microlens array layer, the planar coverage rate C of the random microlens array is 80-90% (because the random microlens array cannot be densely arranged, and cannot reach 100%).
The haze of the randomly arranged micro-lens array layer is 60-90%. Further, the haze of the randomly arranged microlens array layer is 65-85%.
In the randomly arranged microlens array layer, the distance between the main optical axes of the adjacent microlenses is randomly changed within a change range of Dmin～Dmax，10μm≤Dmin＜DmaxLess than or equal to 50 mu m; the width of the micro-lens is determinedA value selected from 10 to 50 μm; the height-width ratio of the micro-lens is a constant value and is selected from 0.1-0.3.
Furthermore, in the randomly arranged microlens array layer, the distance between the main optical axes of the adjacent microlenses is randomly changed, and the change range is 40-50 μm; the width of the micro lens is 40 μm; the height-to-width ratio of the micro-lens is a constant value and is selected from 0.1, 0.2 or 0.3. Further, the haze of the randomly arranged microlens array layer is 65-85%. The foregoing technical solutions include examples 65 to 67 and examples 71 to 78.
The haze of the interference-relieving polarization-maintaining micro-lens film is 60-90%.
The randomly arranged micro-lens array layer is composed of transparent polymer resin AR, and the refractive index nc of the transparent polymer resin is 1.5-1.6. Further, nc is 1.5 or 1.55.
The atomizing layer is a particle-free coating and is composed of a transparent polymer AR, and the refractive index nb of the transparent polymer resin is 1.5.
The haze of the matte layer was 5%.
When linearly polarized light passes through the interference elimination polarization-maintaining micro-lens film, the polarization maintaining degree of the interference elimination polarization-maintaining micro-lens film to the incident linearly polarized light is greater than or equal to 90%.
Further, when linearly polarized light in the LCD backlight passes through the interference-free polarization-maintaining microlens film, the polarized incident light can maintain a higher polarization degree, and the polarization degree is greater than or equal to 95%. Thereby ensuring the final high transmission of the polarizer under the LCD and greatly improving the utilization rate of the backlight source.
The preparation method of the interference-relieving polarization-maintaining micro-lens film comprises the following steps:
(1) mold roller for preparing random arrangement microlens array layer
(2) Preparing a random arrangement microlens array layer on the front surface by using a die roller through UV transfer printing by taking the polarization-maintaining matrix layer as a supporting layer to obtain a solution interference polarization-maintaining microlens film only containing the front surface random arrangement microlens array layer;
further, the preparation method of the interference-free polarization-maintaining micro-lens film comprises the following steps:
(1) taking the polarization-maintaining matrix layer as a supporting layer, and coating an atomizing layer on the back surface to obtain a polarization-maintaining back-coating semi-finished product containing the atomizing layer;
(2) preparing a die roller for randomly arranging the microlens array layer;
(3) and preparing a random arrangement microlens array layer on the front surface (namely the front surface of the polarization-maintaining matrix layer) of the polarization-maintaining back-coated semi-finished product by using a die roller through UV transfer printing to obtain the interference-dissolving polarization-maintaining microlens film simultaneously containing the back surface atomizing layer and the front surface random arrangement microlens array layer.
Drawings
FIG. 1 illustrates the reason for the low light utilization efficiency of LCD;
FIG. 2 is a schematic diagram of a conventional synergy scheme for an LCD;
FIG. 3 is a schematic diagram of a novel synergy scheme for an LCD;
FIG. 4 is a schematic diagram of the depolarization result of a conventional optical film in a novel synergistic optical path;
FIG. 5 is a schematic diagram illustrating the polarization maintaining effect of the polarization maintaining optical film according to the present invention;
FIG. 6 is a schematic diagram of a method for measuring polarization maintaining degree;
FIG. 7 is a schematic diagram of the basic structure of a polarization maintaining optical film;
FIG. 8a is a schematic diagram of the basic structure of a de-interference polarization-maintaining microlens film according to the present invention (randomly arranged microlens array layer, without a backside matte layer);
FIG. 8b is a schematic diagram of the basic structure of a de-interference polarization-maintaining microlens film according to the present invention (randomly arranged microlens array layer, including a rear matte layer);
FIG. 9 is a three-dimensional schematic view of a structured microlens array layer of a common polarization-maintaining microlens film of the invention;
FIG. 10 is a three-dimensional schematic diagram of a randomly arranged microlens array layer of a de-interferometric polarization-maintaining microlens film of the present invention.
Wherein:
11: an upper polarizer; 12: a liquid crystal panel (including a glass substrate, an optical filter, a liquid crystal layer, a thin film transistor, and the like); 13: a lower polarizer; 14: a backlight module; 15: a reflective polarizer;
21: partially polarized light; 22: linearly polarized light in a parallel direction (relative to the transmission axis of the lower polarizer or the paper surface); 23: linearly polarized light in the vertical direction (relative to the transmission axis of the lower polarizer or the paper surface);
3: a conventional optical film;
4: a polarization maintaining optical film;
50: a polarization maintaining substrate layer; 51: a first structural layer; 52: a second structural layer;
54: a particle-free matte layer; 56: a structured microlens array layer; 58: randomly arranged microlens array layer
60: a diaphragm to be tested; 61: a polarizer; 62: a parallel analyzer (parallel to the polarizer for detecting Imax); 63: a vertical analyzer (perpendicular to the polarizer, detect Imin).
Detailed Description
In order to make the structure and features of the invention easier to understand, preferred embodiments of the invention will be described in detail below with reference to the drawings.
The invention provides a polarization-maintaining optical film (4), the polarization-maintaining optical film (4) is used for replacing a traditional optical film (3) in fig. 4, and as shown in fig. 5, after linearly polarized light (22) in the horizontal direction passes through the polarization-maintaining optical film (4), emergent light is kept to be the linearly polarized light (22) in the horizontal direction.
The properties of the polarization-maintaining optical film provided by the present invention were evaluated in the following manner.
(A) Degree of deviation of the protection
As shown in fig. 6, a film (60) to be measured is placed above a polarizer (polarizer) (61) and below a parallel analyzer (polarizer) 62 or a vertical analyzer (polarizer) 63, and the intensity of the outgoing light is measured. When the analyzer angle is parallel to the linearly polarized light, the analyzer is called a parallel analyzer, and the light intensity is called Imax, when the analyzer angle is perpendicular to the linearly polarized light, the analyzer is called a perpendicular analyzer, and the light intensity is called Imin.
As shown in fig. 7, the present invention provides a polarization maintaining optical film, which includes a first structural layer 51, a polarization maintaining substrate layer 50 and a second structural layer 52, wherein the first structural layer is located on the upper surface of the polarization maintaining substrate layer 50, and the second structural layer is located on the lower surface of the polarization maintaining substrate layer 50.
Example 1
The invention provides a polarization-maintaining optical film, as shown in fig. 7, the polarization-maintaining optical film is a polarization-maintaining diffusion film, the first structural layer 51 is a matte layer dl (diffusion layer), and the second structural layer 52 is not present. The thickness T of the substrate layer 50 is 250 μm, the polarization-maintaining substrate layer is made of PC, and has optical isotropy and polarization maintaining degree of > 99%, and the haze of the polarization-maintaining diffusion film is 98%. The haze of the first atomization layer is 98%, the type of the atomization layer is a particle coating, the particle coating is composed of transparent polymer resin PU and transparent polymer particles PMMA, the particle size d is 5-15 micrometers, and the refractive index na of the transparent polymer resin is 1.5. The polarization maintaining diffusion film has a polarization maintaining degree of 82%.
Example 2
As shown in fig. 7, the polarization maintaining optical film provided by the present invention includes a first structural layer 51, a polarization maintaining base layer 50, and a second structural layer 52, wherein the first structural layer is located on the upper surface of the base layer 50, the second structural layer is located on the lower surface of the base layer 50, the polarization maintaining optical film is a polarization maintaining diffusion film, the first structural layer 51 is an matte layer, and the second structural layer 52 is a matte layer. The thickness T of the substrate layer 50 is 250 μm, the polarization-maintaining substrate layer is made of PC, and has optical isotropy and polarization maintaining degree of > 99%, and the haze of the polarization-maintaining diffusion film is 98%. The haze of the first atomization layer is 98%, the type of the atomization layer is a particle coating, the particle coating is composed of transparent polymer resin PU and transparent polymer particles PMMA, the particle size d is 5-15 micrometers, and the refractive index na of the transparent polymer resin is 1.5. The haze of the second matte layer is 5%, the matte layer is a particle-free coating and is composed of a transparent polymer resin AR, and the refractive index nb of the transparent polymer resin is 1.5. The polarization maintaining diffusion film has a polarization maintaining degree of 80%.
Examples 3 to 20
The polarization-maintaining diffusion film provided in example 1, wherein the other parameters are listed in table 1.
TABLE 1 design parameters and optical Properties of polarization-maintaining diffusion films provided in examples 1-20
Figure BDA0003238826320000121
Figure BDA0003238826320000131
Note 1: t is the thickness of the polarization maintaining base layer.
As shown in table 1, examples of the polarization-maintaining diffusion films with different material and design parameter combinations are shown. It can be found that when the substrate layer is made of the polarization-maintaining substrate such as PC, PMMA, TAC, COP, the polarization-maintaining diffusion film prepared has a polarization-maintaining degree of more than 80%, and the thickness T has little influence. When the haze of the atomized layer is reduced, the polarization retention is improved, and the influence of the type, resin and particle material of the atomized layer is not great. When the second structural layer is the low-haze atomization layer, the anti-sticking and anti-scraping effects can be achieved, and the optical influence is small.
Example 21
Fig. 7 shows that the polarization maintaining optical film provided by the present invention includes a first structural layer 51, a polarization maintaining substrate layer 50, and a second structural layer 52, the first structural layer is located on the upper surface of the substrate layer 50, the second structural layer is located on the lower surface of the substrate layer 50, the polarization maintaining optical film is a polarization maintaining microlens film, the first structural layer 51 is a microlens array layer ml (microlens layer), and the second structural layer 52 does not exist. The thickness T of the substrate layer 50 is 250 mu m, the polarization-maintaining substrate layer is made of PC, the optical isotropy is achieved, the polarization maintaining degree is greater than 99%, and the haze of the polarization-maintaining micro-lens film is 96%. The haze of the microlens array layer was 96%, the microlens array layer was formed of a transparent polymer resin AR having a refractive index nc of 1.5. In the microlens array layer, the distance D between the main optical axes of adjacent microlenses is 50 μm, the width of each microlens is W (W is D), the height of each microlens is H, the aspect ratio H/W is 0.5, and at this time, each microlens is hemispherical; the polarization maintaining degree of the polarization maintaining micro lens is 85%.
Example 22
Fig. 7 shows a polarization maintaining optical film provided by the present invention, which includes a first structural layer 51, a polarization maintaining substrate layer 50, and a second structural layer 52, wherein the first structural layer is located on the upper surface of the substrate layer 50, the second structural layer is located on the lower surface of the substrate layer 50, the polarization maintaining optical film is a polarization maintaining microlens film, the first structural layer 51 is a microlens array layer, and the second structural layer 52 is an atomizing layer. The thickness T of the substrate layer 50 is 250 mu m, the polarization-maintaining substrate layer is made of PC, the optical isotropy is achieved, the polarization maintaining degree is greater than 99%, and the haze of the polarization-maintaining micro-lens film is 96%. The haze of the microlens array layer is 96%, the microlens array layer is composed of a transparent polymer resin AR, and the refractive index nc of the transparent polymer resin is 1.5. The haze of the atomization layer is 5%, the type of the atomization layer is a particle-free coating and is composed of a transparent polymer AR, and the refractive index nb of the transparent polymer resin is 1.5. The polarization maintaining micro-lens film has 85% polarization maintaining degree.
Examples 23 to 36
The polarization maintaining microlens film as provided in example 21, wherein the other parameters are listed in table 2.
TABLE 2 design parameters and optical Properties of examples 21-36
Figure BDA0003238826320000141
Figure BDA0003238826320000151
Note 1: t is the thickness of the base layer; d is the distance between the main optical axes of the adjacent micro lenses; w is the width of the micro-lens, H is the height of the micro-lens, and H/W is the aspect ratio.
As shown in Table 2, examples of polarization maintaining microlens films with different material and design parameter combinations are provided. It can be found that when the substrate layer is made of the polarization-maintaining substrate such as PC, PMMA, TAC, COP, the polarization-maintaining microlens films obtained have polarization maintaining degrees of more than 80%, and the thickness T has little influence. When the haze of the microlens layer is reduced, the polarization maintaining degree is improved, and when the refractive index of the transparent polymer is reduced, or the aspect ratio is reduced, the haze is also reduced, the polarization maintaining degree is also improved, and the influence of the kind of the resin is not great. When the second structural layer is the low-haze atomization layer, the anti-sticking and anti-scraping effects can be achieved, and the optical influence is small.
Example 37
As shown in fig. 7, the polarization maintaining optical film provided by the present invention includes a first structural layer 51, a polarization maintaining substrate layer 50, and a second structural layer 52, the first structural layer is located on the upper surface of the substrate layer 50, the second structural layer is located on the lower surface of the substrate layer 50, the polarization maintaining optical film is a polarization maintaining prism film, the first structural layer 51 is a prism layer pl (prism layer), and the second structural layer 52 is not present. The thickness T of the substrate layer 50 is 250 μm, the polarization-maintaining substrate layer is made of PC (polycarbonate), the material is optically isotropic, the polarization maintaining degree is greater than 99%, the prism layer is made of a transparent polymer resin AR, and the refractive index nd of the transparent polymer resin is 1.55. The prism layer is formed by tiling triangular prism ribs, the cross sections of the triangular prism ribs are isosceles triangles, the bottom sides of the triangles are 50 micrometers, and the vertex angles are 90 degrees. The polarization maintaining degree of the polarization maintaining prism film is 98%.
Example 38
As shown in fig. 7, the polarization maintaining optical film provided by the present invention includes a first structural layer 51, a polarization maintaining substrate layer 50, and a second structural layer 52, the first structural layer is located on the upper surface of the substrate layer 50, the second structural layer is located on the lower surface of the substrate layer 50, the polarization maintaining optical film is a polarization maintaining prism film, the first structural layer 51 is a prism layer pl (prism layer), and the second structural layer 52 is an matte layer. The thickness T of the substrate layer 50 is 250 μm, and the polarization-maintaining substrate layer is made of PC, optically isotropic material, and polarization-maintaining material>99%, the prism layer is composed of a transparent polymer resin AR having a refractive index nd of 1.55. The prism layer is formed by tiling prism ribs, the cross section of each prism rib is an isosceles triangle, the bottom edge of each triangle is 50 micrometers, and the vertex angle is 90 degrees°. The haze of the atomization layer is 5%, the type of the atomization layer is a particle-free coating and is composed of a transparent polymer AR, and the refractive index nb of the transparent polymer resin is 1.5. The polarization maintaining degree of the polarization maintaining prism film is 97%.
Examples 39 to 50
The polarization maintaining prism film provided in example 37, wherein the other parameters are listed in table 3.
TABLE 3 design parameters and optical Properties of examples 37-50
Figure BDA0003238826320000161
Note 1: t is the thickness of the base layer.
As shown in table 3, examples of polarization maintaining prism films with different material and design parameters are provided. It can be found that when the substrate layer is made of the polarization-maintaining substrate such as PC, PMMA, TAC, COP, the polarization-maintaining prism films prepared by the method have polarization-maintaining degree of more than 80% and the thickness T has little influence. When the material, the refractive index, the bottom edge and the top angle of the prism layer are changed, the polarization maintaining degree is basically not influenced. When the second structural layer is an atomizing layer, the effects of adhesion prevention and scratch resistance can be achieved, and when the haze is increased, the polarization degree is slightly reduced.
Example 51
As shown in fig. 7, the polarization maintaining optical film provided by the present invention includes a first structural layer 51, a polarization maintaining substrate layer 50, and a second structural layer 52, the first structural layer is located on the upper surface of the substrate layer 50, the second structural layer is located on the lower surface of the substrate layer 50, the polarization maintaining optical film is a polarization maintaining inverse prism film, the first structural layer 51 does not exist, and the second structural layer 52 is an inverse prism layer RL (reverse-prism layer). The thickness T of the substrate layer 50 is 250 μm, the polarization-maintaining substrate layer is made of PC (polycarbonate), the optical isotropy is achieved, the polarization maintaining degree is greater than 99%, the inverse prism layer is made of a transparent polymer resin AR, and the refractive index nd of the transparent polymer resin is 1.55. The inverted prism layer is formed by tiling triangular prism ribs, the cross sections of the triangular prism ribs are isosceles triangles or common triangles, the width L of the bottom edge of each triangle is 50 micrometers, the vertex angle theta is selected from 60 degrees, one larger bottom angle alpha is 90 degrees to 0.5 theta + gamma, and the deflection angle gamma is 0 degree. The polarization maintaining degree of the polarization maintaining inverse prism film is 98%.
Example 52
As shown in fig. 7, the polarization maintaining optical film provided by the present invention includes a first structural layer 51, a polarization maintaining substrate layer 50, and a second structural layer 52, the first structural layer is located on the upper surface of the substrate layer 50, the second structural layer is located on the lower surface of the substrate layer 50, the polarization maintaining optical film is a polarization maintaining inverse prism film, the first structural layer 51 is an matte layer, and the second structural layer 52 is an inverse prism layer RL (reverse-prism layer). The thickness T of the substrate layer 50 is 250 μm, the polarization-maintaining substrate layer is made of PC (polycarbonate), the optical isotropy is achieved, the polarization maintaining degree is greater than 99%, the inverse prism layer is made of a transparent polymer resin AR, and the refractive index nd of the transparent polymer resin is 1.55. The inverted prism layer is formed by tiling triangular prism ribs, the cross sections of the triangular prism ribs are isosceles triangles, the width L of the bottom edge of each triangle is 50 mu m, the vertex angle theta is selected from 60 degrees, one larger bottom angle alpha is 90-0.5 theta + gamma, and the deflection angle gamma is 0 deg. The haze of the atomization layer is 30%, the type of the atomization layer is a particle-free coating and is composed of a transparent polymer AR, and the refractive index nb of the transparent polymer resin is 1.5. The polarization maintaining degree of the polarization maintaining prism film is 95%.
Examples 53 to 64
The polarization maintaining and reverse prism film provided in example 51, wherein the other parameters are listed in table 4.
TABLE 4 design parameters and optical Properties of examples 51-64
Figure BDA0003238826320000171
Figure BDA0003238826320000181
Note 1: t is the thickness of the base layer.
As shown in table 4, examples of polarization-maintaining inverse prism films with different material and design parameters are provided. It can be found that when the substrate layer is made of the polarization-maintaining substrate such as PC, PMMA, TAC, COP, the polarization-maintaining degree of the prepared polarization-maintaining inverse prism film is more than 80%, and the thickness T has little influence. When the material, the refractive index, the bottom edge and the top angle of the inverse prism layer are changed, the polarization maintaining degree is basically not influenced. When the first structural layer is an atomized layer, the effects of adhesion resistance and scratch resistance can be achieved, and when the haze is increased, the polarization degree is slightly reduced.
Examples 65 to 71
In the polarization maintaining microlens films of examples 21, 1-4 and 65-71, the substrate layer is made of PC, the thickness T is 250 μm, the random microlens array layer is made of AR, and the refractive index is 1.5. The back-side matte layer of comparative examples 1 to 4 and examples 65 to 70 (shown in fig. 8 a) and the matte layer containing the matte layer of example 71 (shown in fig. 8 b) were the same, and the matte layer was a particle-free coating with a haze of 5%, the resin material of the particle-free coating was AR, and the refractive index was 1.5. The comparative examples 1 to 4 have poor interference resolution effect, the polarization maintaining degree of 85 to 97 percent, the examples 65 to 67 and 71 have excellent interference resolution effect, the polarization maintaining degree of 95 to 97 percent, the examples 68 to 70 have good interference resolution effect, and the polarization maintaining degree of 94 to 97 percent. The structural design parameters of the interference-free polarization-maintaining microlens films of comparative examples 1-4 and 65-71 are listed in Table 5.
Examples 72 to 78
In example 21, the polarization maintaining microlens film according to examples 72 to 78, wherein the material of the base layer is one of PC, TAC, PMMA and COP, the thickness T is one of 125, 100, 50 and 25 μm, the material of the random arrangement microlens array layer is AR, and the refractive index is 1.55 or 1.5. Examples 72 to 78 have no backside matte (as shown in FIG. 8 a), examples 72 to 78 have excellent interference rejection and polarization maintaining degree of 96%. The other design parameters of the de-interferometric polarization-maintaining microlens film structures described in examples 72-78 are listed in Table 5.
TABLE 5 design parameters and Performance of the polarization maintaining microlens films provided in examples 65-78 and comparative examples 1-4
Figure BDA0003238826320000182
Figure BDA0003238826320000191
Note 1: t is the thickness of the base layer; dmin/DmaxAre respectively a phaseThe lower limit/upper limit of the range of randomly changing the distance between the main optical axes of the adjacent micro lenses; w is the width of the microlens; b is the height-width ratio of the micro lens; and C is the plane coverage rate of the micro-lens array.
As shown in table 5, examples and comparative examples of polarization-maintaining microlens films matching different materials and design parameters are shown, wherein comparative examples 1 to 4 are common polarization-maintaining microlens films, regular equal-height structures are adopted, D and W are the same, the aspect ratio is a constant value, the larger the aspect ratio, the higher the haze is, the lower the polarization maintaining degree is, and the coverage rate C is 100% due to the regular structural close arrangement, but the regular structural interference resolving capability is poor. Examples 65-78 show that the random microlens arrays are more disordered and the de-interference capability is better when the random variation range of D is larger (compare examples 65-67 with 68-70). In addition, in the same random variation value range, different microlenses produce different coverage rates to obtain different optical effects such as haze and polarization maintaining degree, but the interference resolving capability is basically equivalent (as in examples 68 to 70). In addition, it can be seen from comparative examples 66 and 71 that the low haze back coating layer does not greatly affect the overall optical effect, and from comparative examples 66 and 72 to 78 that the material and thickness of the base layer do not greatly affect the performance.
It should be noted that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention. All equivalent changes and modifications made according to the disclosure of the present invention are covered by the scope of the claims of the present invention.

Claims (10)

1. The polarization-maintaining optical film is characterized by comprising a polarization-maintaining base layer, a first structural layer and/or a second structural layer, wherein the first structural layer is positioned on the upper surface of the polarization-maintaining base layer, and the second structural layer is positioned on the lower surface of the polarization-maintaining base layer; when linearly polarized light passes through the polarization-maintaining optical film, the polarization-maintaining optical film has a polarization maintaining degree of greater than or equal to 80% for incident linearly polarized light.
2. The polarization-maintaining optical film of claim 1, wherein the polarization-maintaining optical film is a polarization-maintaining microlens film; the polarization-maintaining matrix layer is an optically isotropic transparent polymer; the polarization maintaining degree of the polarization maintaining matrix layer is more than 99 percent; the material of the polarization-maintaining matrix layer is selected from one or the combination of at least two of methyl methacrylate (PMMA), Polycarbonate (PC), Triacetylcellulose (TAC) and Cyclic Olefin Polymer (COP); the first structural layer of the polarization-maintaining micro-lens film is a micro-lens array layer; in the microlens array layer, the coordinates of the main optical axes of three adjacent microlenses are connected to form a regular triangle, or the coordinates of the main optical axes of four adjacent microlenses are connected to form a square; the microlenses in the microlens array are closely arranged.
3. The polarization maintaining optical film according to claim 2, wherein in the microlens array layer, a pitch D of principal optical axes of adjacent microlenses is 10 to 50 μm, a width of a microlens is W (W ═ D), a height of a microlens is H, and an aspect ratio H/W is 0.05 to 0.5.
4. A polarization-maintaining microlens film of interference elimination, wherein the polarization-maintaining microlens film of interference elimination includes a polarization-maintaining base layer, a first structural layer and a second structural layer; the first structural layer is a randomly arranged micro-lens array layer and is positioned on the upper surface of the substrate layer; the second structural layer does not exist or is an atomizing layer and is positioned on the lower surface of the substrate layer, and in the randomly arranged micro-lens array layer, the coordinates of the main optical axes of the three adjacent micro-lenses are connected to form a common triangle.
5. The de-interference polarization-maintaining microlens film according to claim 4, wherein the distance D between the main optical axes of adjacent microlenses varies randomly within a certain range of values; the width W of the micro lens is a fixed value; the height-to-width ratio B (B ═ H/W) of the microlens is constant.
6. The de-interferometric polarization-maintaining microlens film according to claim 4, wherein in the randomly arranged microlens array layer, the planar coverage C of the random microlens array is 80% to 90%.
7. The film according to claim 4, wherein the haze of the randomly arranged microlens array layer is 60-90%, and the haze of the matte layer is 5%.
8. The de-interferometric polarization-maintaining microlens film according to claim 4, wherein in the randomly arranged microlens array layer, the distance between the principal optical axes of the adjacent microlenses varies randomly within a range Dmin～Dmax，10μm≤Dmin＜DmaxLess than or equal to 50 mu m; the width of the micro lens is a fixed value and is selected from 10-50 mu m; the height-width ratio of the micro-lens is a constant value and is selected from 0.1-0.3.
9. The de-interferometric polarization-maintaining microlens film according to claim 4, wherein in the randomly arranged microlens array layer, the distance between the principal optical axes of adjacent microlenses varies randomly, ranging from 40 μm to 50 μm; the width of the micro lens is 40 μm; the height-to-width ratio of the micro-lens is a constant value and is selected from 0.1, 0.2 or 0.3.
10. The method of producing a polarization-maintaining optical film according to any one of claims 1 to 3, wherein the first structural layer or the second structural layer is produced by applying a resin or a resin formulation containing particles to the front/back surfaces of the polarization-maintaining base layer in sequence by a coating, microreplication, or thermoforming process; the micro-replication and hot-press molding are suitable for preparing the atomizing layer and the micro-lens layer of the polarization-maintaining micro-lens film.
CN202111010655.3A 2020-08-31 2021-08-31 Polarization-preserving optical film, interference-relieving polarization-preserving micro-lens film and preparation method thereof Active CN114114507B (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
CN202010897198 2020-08-31
CN2020108971983 2020-08-31
CN202110869387 2021-07-30
CN2021108693874 2021-07-30

Publications (2)

Publication Number Publication Date
CN114114507A true CN114114507A (en) 2022-03-01
CN114114507B CN114114507B (en) 2023-07-25

Family

ID=80441054

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111010655.3A Active CN114114507B (en) 2020-08-31 2021-08-31 Polarization-preserving optical film, interference-relieving polarization-preserving micro-lens film and preparation method thereof

Country Status (1)

Country Link
CN (1) CN114114507B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114114508A (en) * 2020-08-31 2022-03-01 宁波激智科技股份有限公司 Polarization-maintaining optical film, anti-adsorption polarization-maintaining micro-lens film and preparation method thereof
CN114114509A (en) * 2020-08-31 2022-03-01 宁波激智科技股份有限公司 Polarization-maintaining optical film, interference-relieving polarization-maintaining micro-lens film and preparation method thereof

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1305607A (en) * 1998-06-11 2001-07-25 3M创新有限公司 Rear projection screen
CN1734290A (en) * 2004-06-08 2006-02-15 索尼株式会社 Light diffusing film and method of producing the same as well as screen
JP2014092600A (en) * 2012-11-01 2014-05-19 Seiko Epson Corp Method for manufacturing microlens array substrate, microlens array substrate, electro-optic device, and electronic equipment
CN105911804A (en) * 2015-02-25 2016-08-31 全视技术有限公司 Spatially-Interleaved Polarization Converter For LCOS Display
JP2017107174A (en) * 2015-11-30 2017-06-15 大日本印刷株式会社 Method of manufacturing laminate, laminate, backlight device, and display
CN210222283U (en) * 2019-07-26 2020-03-31 深圳Tcl新技术有限公司 Microlens brightness enhancement film, backlight module, liquid crystal display screen and television
CN114114509A (en) * 2020-08-31 2022-03-01 宁波激智科技股份有限公司 Polarization-maintaining optical film, interference-relieving polarization-maintaining micro-lens film and preparation method thereof

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1305607A (en) * 1998-06-11 2001-07-25 3M创新有限公司 Rear projection screen
CN1734290A (en) * 2004-06-08 2006-02-15 索尼株式会社 Light diffusing film and method of producing the same as well as screen
JP2014092600A (en) * 2012-11-01 2014-05-19 Seiko Epson Corp Method for manufacturing microlens array substrate, microlens array substrate, electro-optic device, and electronic equipment
CN105911804A (en) * 2015-02-25 2016-08-31 全视技术有限公司 Spatially-Interleaved Polarization Converter For LCOS Display
JP2017107174A (en) * 2015-11-30 2017-06-15 大日本印刷株式会社 Method of manufacturing laminate, laminate, backlight device, and display
CN210222283U (en) * 2019-07-26 2020-03-31 深圳Tcl新技术有限公司 Microlens brightness enhancement film, backlight module, liquid crystal display screen and television
CN114114509A (en) * 2020-08-31 2022-03-01 宁波激智科技股份有限公司 Polarization-maintaining optical film, interference-relieving polarization-maintaining micro-lens film and preparation method thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114114508A (en) * 2020-08-31 2022-03-01 宁波激智科技股份有限公司 Polarization-maintaining optical film, anti-adsorption polarization-maintaining micro-lens film and preparation method thereof
CN114114509A (en) * 2020-08-31 2022-03-01 宁波激智科技股份有限公司 Polarization-maintaining optical film, interference-relieving polarization-maintaining micro-lens film and preparation method thereof

Also Published As

Publication number Publication date
CN114114507B (en) 2023-07-25

Similar Documents

Publication Publication Date Title
TWI408405B (en) Optical film composite
CN1058090C (en) Backlight assembly for an electro-optical display
CN114114507B (en) Polarization-preserving optical film, interference-relieving polarization-preserving micro-lens film and preparation method thereof
CN102830539A (en) Liquid crystal display device
KR20120038445A (en) Light diffusion film and liquid crystal display device comprising same
CN114114498B (en) Polarization-preserving optical film and polarization-preserving diffusion film
KR102448120B1 (en) Optical film for improving contrast ratio, polarizing plate comprising the same and liquid crystal display apparatus comprising the same
CN114114499A (en) Polarization-maintaining optical film, polarization-maintaining diffusion film and double-sided fog polarization-maintaining diffusion film
CN114114500A (en) Polarization-maintaining optical film, polarization-maintaining diffusion film and double-sided fog polarization-maintaining diffusion film
KR20200006443A (en) Polarizing plate and optical display apparatus comprising the same
KR101219591B1 (en) Back light guide plate and manufacturing method for the same
US20100026934A1 (en) Light uniforming polarization recycling film
KR101813753B1 (en) Liquid crystal display apparatus
CN101430457A (en) Liquid crystal display device
CN114114509B (en) Polarization-preserving optical film, interference-relieving polarization-preserving micro-lens film and preparation method thereof
CN114217372A (en) Polarization-maintaining optical film and polarization-maintaining prism film
KR100932606B1 (en) Optical film and backlight unit including same
CN114114496B (en) Polarization-maintaining optical film and preparation method thereof
CN114114508B (en) Polarization-preserving optical film, anti-adsorption polarization-preserving micro-lens film and preparation method thereof
CN111065962B (en) Backlight unit and liquid crystal display device
CN114114504B (en) Polarization-preserving optical film and interference-relieving polarization-preserving composite prism film
CN114114501A (en) Polarization-maintaining optical film and polarization-maintaining prism film
CN215932185U (en) Composite optical film and display device
CN114114497A (en) Polarization-maintaining optical film and polarization-maintaining prism film
CN101339326B (en) Polarized light reclamation film possessing dodging characteristic

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant