[go: up one dir, main page]

WO2025133865A1 - Film de commande de lumière ayant un profil de transmission asymétrique comprenant une couche de transmission de lumière - Google Patents

Film de commande de lumière ayant un profil de transmission asymétrique comprenant une couche de transmission de lumière Download PDF

Info

Publication number
WO2025133865A1
WO2025133865A1 PCT/IB2024/062664 IB2024062664W WO2025133865A1 WO 2025133865 A1 WO2025133865 A1 WO 2025133865A1 IB 2024062664 W IB2024062664 W IB 2024062664W WO 2025133865 A1 WO2025133865 A1 WO 2025133865A1
Authority
WO
WIPO (PCT)
Prior art keywords
control film
light control
light
layer
less
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.)
Pending
Application number
PCT/IB2024/062664
Other languages
English (en)
Inventor
Daniel J. Schmidt
Tao Liu
Caleb T. NELSON
Kristy A. GILLETTE
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.)
3M Innovative Properties Co
Original Assignee
3M Innovative Properties Co
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 3M Innovative Properties Co filed Critical 3M Innovative Properties Co
Publication of WO2025133865A1 publication Critical patent/WO2025133865A1/fr
Pending legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/003—Light absorbing elements
    • 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
    • G02F1/133524—Light-guides, e.g. fibre-optic bundles, louvered or jalousie light-guides
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B2207/00—Coding scheme for general features or characteristics of optical elements and systems of subclass G02B, but not including elements and systems which would be classified in G02B6/00 and subgroups
    • G02B2207/123—Optical louvre elements, e.g. for directional light blocking

Definitions

  • a light control film having a structured first major surface opposite a second major surface.
  • the structured first major surface includes a plurality of structures extending in a thickness direction of the light control film separated by one or more grooves. Each structure has a first side surface opposite a second side surface. Each groove has one or more substantially planar landings joining the corresponding adjacent structures.
  • the first side surface is substantially orthogonal with a first adjacent landing of the one or more landings, and the second side surface makes an angle greater than about 95 degrees with a second adjacent landing of the one or more landings.
  • At least 70% of the first and second side surfaces and at most 30% of the one or more landings are coated with a cover layer.
  • the cover layer coated on the first side surface has a first average thickness Tl
  • the cover layer coated on the second side surface has a second average thickness T2, such that Tl is greater than T2.
  • a light control film having a structured first major surface opposite a second major surface.
  • the structured first major surface includes a plurality of structures extending in a thickness direction of the light control film separated by one or more grooves.
  • Each structure includes a first side surface opposite a second side surface, and each groove has one or more substantially planar landings joining the corresponding adjacent structures.
  • the first side surface is substantially orthogonal with a first adjacent landing of the one or more landings, and the second side surface makes an angle greater than about 95 degrees with a second adjacent landing of the one or more landings. At least 70% of the first and second side surfaces and at most 30% of the one or more landings are coated with a cover layer.
  • the cover layer on the first and second side surfaces is coated with a light transmissive layer having a plurality of first inorganic particles at a volume loading of greater than about 5%.
  • the light transmissive layer coated on the first side surface has a first average thickness T3
  • the light transmissive layer coated on the second side surface has a second average thickness T4, such that T3 is greater than T4.
  • a method of making a light control film including providing a substantially light transmissive film having a structured first major surface and an opposing second major surface, the structured first major surface including a plurality of structures separated by one or more grooves extending in a thickness direction of the light control film, each structure having a first side surface opposite a second side surface, and each groove having one or more substantially planar landings joining the corresponding adjacent structures, the first side surface substantially orthogonal with a first adjacent landing of the one or more landings, the second side surface making an angle greater than about 95 degrees with a second adjacent landing of the one or more landings; covering the structured first major surface with a cover layer; covering the cover layer with a light transmissive layer comprising a plurality of first inorganic particles at a volume loading of greater than about 5%; etching the light transmissive layer using a directional first etching process such that the light transmissive layer coated on the first side surface has
  • FIGS. 1A-1C provide side views of a light control film with an asymmetric transmission profile, in accordance with an embodiment of the present description
  • FIG. 2 provides a top view of a light control film with an asymmetric transmission profile, in accordance with an embodiment of the present description
  • FIGS. 3A-3B illustrate examples of a display system having a light control film with an asymmetric transmission profile, in accordance with an embodiment of the present description
  • FIG. 4 is a plot of a light transmission profile of a light control film with an asymmetric transmission profile, in accordance with an embodiment of the present description
  • FIGS. 5A-5B illustrate examples of a light control film featuring louvers/side surfaces with a multilayer construction, in accordance with an embodiment of the present description
  • FIGS. 6A-6C illustrate examples of a light control film featuring louvers/side surfaces with a cover layer and a light transmissive layer, in accordance with an embodiment of the present description
  • FIGS. 7A-7B illustrate a method of making a light control film, in accordance with an embodiment of the present description.
  • FIG. 8 illustrates an alternate method of making a light control film, in accordance with an embodiment of the present description.
  • FIGS. 9A-9B are illustrations supporting the Examples section.
  • an improved light control film provides a significant increase in transmission efficiency (e.g., about 60%, compared to around 35% with current methods).
  • a new method is provided which is based on layer-by-layer (LbL) coating and selective removal process (e.g., removal through directional etching).
  • the master can be metallic, such as nickel, chrome- or nickel-plated copper or brass, or can be a thermoplastic material that is stable under the polymerization conditions and has a surface energy that allows clean removal of the polymerized material from the master.
  • the base layer is a preformed film, one or more of the surfaces of the film can optionally be primed or otherwise be treated to promote adhesion to the organic material of the microstructure.
  • base layer materials include polyethylene terephthalate (PET) and polycarbonate (PC).
  • PET films include photograde polyethylene terephthalate, available from DuPont Films (Wilmington, DE), under the trade designation “Melinex 618”.
  • optical grade polycarbonate films include LEXAN polycarbonate film 8010, available from GE Polymershapes, Seattle, WA, and Panlite 1151, available from Teijin Kasei, Alpharetta, GA.
  • the cover layer may have an average thickness of greater than about 0.05 microns, or greater than about 0.1 microns, or greater than about 0.15 microns, or greater than about 0.2 microns, or greater than about 0.25 microns, or greater than about 0.3 microns, or greater than about 0.35 microns, or greater than about 0.4 microns, or greater than about 0.45 microns, or greater than about 0.5 microns, or greater than about 0.55 microns, or greater than about 0.6 microns, or greater than about 0.65 microns, or greater than about 0.7 microns, or greater than about 0.75 microns, or greater than about 1.0 microns, or greater than about 1.25 microns, or greater than about 1.5 microns, or greater than about 2 microns, or greater than about 2.5 microns, or greater than about 3 microns.
  • the light absorbing cover layer may have an optical density, at one or more wavelengths from 100 nm to 1 mm of greater than about 0.1, or greater than about 0.2, or greater than about 0.4, or greater than about 0.6, or greater than about 0.8, or greater than about 1, or greater than about 1.1, or greater than about 1.2, or greater than about 1.3, or greater than about 1.4, or greater than about 1.5, or greater than about 2, or greater than about 2.5, or greater than about 3, or greater than about
  • the optical density is less than about 3.0, or less than about
  • optical density is between 0.5 and 2.5, or between 1.0 and 2.0 or between 1.2 and 1.8.
  • optical density shall be defined as -loglO(T), where T is the optical transmission of the film, and T is defined as Io/I t , where I o is the intensity of incident light and I t is the intensity of the transmitted light (light passing through the medium). For example, if transmission, T, is 1%, the optical density is calculated as -loglO(O.Ol) which is equal to an optical density of 2.0.
  • a display system may include any of the light control films described herein.
  • the display may be configured to form an image to a viewer, and the light control film may be disposed between the viewer and the display.
  • the display system may include a display configured to form an image to a viewer, an extended light source (e.g., a backlight), and any of the light control film embodiments described herein.
  • the light control film may be disposed between the extended light source and the display.
  • the display may be any type of appropriate display device, including but not limited to an LCD or on OLED display.
  • the cover layer may include a core layer sandwiched between a first cladding layer and a second cladding layer.
  • the core layer may have a first concentration, Cl, of a light absorbing material
  • the first and second cladding layers may have a second concentration, C2, of the light absorbing material, wherein C2 is less than Cl.
  • the core layer may include 30 wt. % to 100 wt. % of light absorbing material and the first and second cladding layers may each include 0.5 wt. % to 50 wt. % of light absorbing material.
  • the core layer may include 15 vol. % to 90 vol. % of light absorbing material and the first and second cladding layers may each include 0.3 vol. % to 35 vol. % of light absorbing material.
  • the core layer may have an optical density, at one or more wavelengths from 100 nm to 1 mm of greater than about 0.1, or greater than about 0.2, or greater than about 0.4, or greater than about 0.6, or greater than about 0.8, or greater than about 1, or greater than about 1.1, or greater than about 1.2, or greater than about 1.3, or greater than about 1.4, or greater than about 1.5, or greater than about 2, or greater than about 2.5, or greater than about 3, or greater than about 3.5, or greater than about 4, or greater than about 4.5, or greater than about 5, or greater than about 5.5, or greater than about 6.
  • thicknesses of the first cladding layer and the core layer on the first side surface are substantially the same as corresponding thicknesses of the of the first cladding layer and the core layer on the second side surface, wherein a thickness of the second cladding layer on the first side surface is greater than a thickness of the second cladding layer on the second side surface.
  • the light control film may have an asymmetric transmission profile.
  • a transmission profile of the light control film may have a peak transmission at a viewing angle having a magnitude greater than or equal to about 10 degrees, and an average transmission percentage across the entire profile equal to 50% or less of the peak transmission.
  • the transmission profile may have a peak transmission percentage at least 10 degrees from normal, and lower average transmission levels on either side of the location of the peak transmission.
  • transmission percentage at an angle of 50 degrees may be less than 10%, less than 5%, or less than 2%
  • transmission percentage at an angle of 60 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of 70 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of 80 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -20 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -30 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -40 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -50 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -60 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -50 degrees may be less than 10%, less than 5%, or less than 2%
  • transmission percentage at an angle of -60 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -70 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -80 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of +20 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of +30 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of +40 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of +50 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of +60 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of +60 degrees may be less than 10%, less than
  • the transmission profile exhibits a “top-hat shape”; for example, peak transmission percentage is nearly constant (e.g., within ⁇ 2%T) within a range of viewing (polar angles) for example within 10 degrees, within 20 degrees, or within 30 degrees, or within 40 degrees, or within 50 degrees.
  • the transmission profile of the light control film may have a peak transmission at a viewing angle having a magnitude between about 10 degrees and about 30 degrees.
  • an average transmission percentage across the profile may be equal to 50% or less of the peak transmission (i.e., the peak transmission percentage).
  • each structure may include a first side surface opposite a second side surface, separated by a substantially planar landing of one of the grooves of the one or more grooves (i.e, each groove may have one or more substantially planar landings joining the side surfaces of corresponding, adjacent structures facing each other across the groove).
  • the first side surface may be substantially orthogonal with a first adjacent landing of the one or more landings
  • the second side surface may make an angle greater than 95 degrees (or greater than 100 degrees, or greater than 105 degrees, or greater than 110 degrees, or greater than 115 degrees, or greater than 120 degrees, or greater than 125 degrees, or greater than 130 degrees) with a second adjacent landing of the one or more landings.
  • the method further includes covering the structured first major surface with a cover layer (e.g., a light-absorbing cover layer).
  • the method may further include etching the cover layer using a directional first etching process (e.g., reactive ion etching) to remove the cover layer from more than about 70%, or more than about 80%, or more than about 90%, or more than about 95% of the one or more landings, but from less than about 30%, or less than about 25%, or less than about 20%, or less than about 15%, or less than about 10%, or less than about 5%) of each of the first and second side surfaces, such that, the cover layer coated on the first side surface has a first average thickness Tl, the cover layer coated on the second side surface having a second average thickness T2, and Tl is greater than T2.
  • a directional first etching process e.g., reactive ion etching
  • Tl may be greater than T2 by at least a factor of 1.1, or at least a factor of 1.3, or at least a factor of 1.5, or at least a factor of 2.0, or at least a factor of 2.5, or at least a factor of 3.0, or at least a factor of 3.5, or at least a factor of 4.0, or at least a factor of 4.5, or at least a factor of 5.0, or at least a factor of 5.5, or at least a factor of 6.0.
  • the method of making a light control film may further include covering and substantially planarizing the structured first major surface with a planarizing overcoat.
  • the planarizing overcoat covering may include an optically clear adhesive.
  • the planarizing overcoat may include a polymerizable resin (e.g., it may be the same polymerizable resin used to make the structured surface, described elsewhere herein).
  • a refractive index of the planarizing overcoat may be different from a refractive index of a material comprising the first major surface by greater than about 0.07. In other embodiments, a refractive index of the planarizing overcoat may be substantially the same as a refractive index of a material comprising the first major surface.
  • the cover layer applied in the method may be light absorbing.
  • the light absorbing cover layer may include a poly electrolyte.
  • the light absorbing cover layer may include a plurality of light absorbing particles, including, but not limited to, a dye, a pigment, and a carbon black, or combinations thereof.
  • the light absorbing cover layer may have an optical density, at one or more wavelengths from 100 nm to 1 mm of greater than about 0.1, or greater than about 0.2, or greater than about 0.4, or greater than about 0.6, or greater than about 0.8, or greater than about 1, or greater than about 1.1, or greater than about 1.2, or greater than about 1.3, or greater than about 1.4, or greater than about 1.5, or greater than about 2, or greater than about 2.5, or greater than about 3, or greater than about 3.5, or greater than about 4, or greater than about 4.5, or greater than about 5, or greater than about 5.5, or greater than about 6.
  • the cover layer may include a core layer sandwiched between a first cladding layer and a second cladding layer.
  • the core layer may have a first concentration, Cl, of a light absorbing material and the first and second cladding layers may have a second concentration, C2, of the light absorbing material, wherein C2 ⁇ C 1.
  • the core layer may include 30 wt. % to 100 wt. % of light absorbing material and the first and second cladding layers may each include 0.5 wt. % to 50 wt. % of light absorbing material.
  • the core layer may include 15 vol. % to 90 vol. % of light absorbing material and the first and second cladding layers may each include 0.3 vol. % to 35 vol. % of light absorbing material.
  • the core layer may have an optical density, at one or more wavelengths from 100 nm to 1 mm, of greater than about 0.1, or greater than about 0.2, or greater than about 0.4, or greater than about 0.6, or greater than about 0.8, or greater than about 1, or greater than about 1.1, or greater than about 1.2, or greater than about 1.3, or greater than about 1.4, or greater than about 1.5, or greater than about 2, or greater than about 2.5, or greater than about 3, or greater than about 3.5, or greater than about 4, or greater than about 4.5, or greater than about 5, or greater than about 5.5, or greater than about 6.
  • a light control film includes a structured first major surface opposite a second major surface.
  • the structured first major surface may include a plurality of structures extending in a thickness direction of the light control film and separated by one or more grooves.
  • each structure may include a first side surface opposite a second side surface.
  • the plurality of structures may include linear structures extending substantially across a width direction (e.g., a y-direction) of the light control film and arranged along an orthogonal length direction (e.g., an x-direction) of the light control film.
  • each linear structure may be separated from each adjacent linear structure by a groove of the one or more grooves.
  • each groove may have one or more substantially planar landings joining (i.e., connecting) the side surfaces of corresponding, adjacent structures.
  • the first side surface may be substantially orthogonal with a first adjacent landing of the one or more landings (i.e., substantially vertical in the thickness direction of the light control film).
  • the second side surface may make an angle greater than about 95 degrees, or about 100 degrees, or about 105 degrees, or about 110 degrees, or about 115 degrees, or about 120 degrees, or about 125 degrees, or about 130 degrees with a second adjacent landing of the one or more landings.
  • At least 70% (or at least 75%, or at least 80%, or at least 85%, or at least 90%, or at least 95%) of the first and second side surfaces, and at most 30% (or at most 25%, or at most 20%, or at most 15%, or at most 10%, or at most 5%) of the one or more landings may be coated with a cover layer (e.g., a light-absorbing cover layer).
  • the cover layer on the first and second side surfaces may be coated with a light transmissive layer including a plurality of first inorganic particles at a volume loading of greater than about 5%.
  • the cover layer may be light absorbing.
  • the light absorbing cover layer may include a polyelectrolyte.
  • the light absorbing cover layer may include a plurality of light absorbing particles.
  • the light absorbing particles include one or more of a dye, a pigment, and a carbon black.
  • the light absorbing cover layer may have an optical density of greater than about 0.1.
  • transmission percentage at an angle of 50 degrees may be less than 10%, less than 5%, or less than 2%
  • transmission percentage at an angle of 60 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of 70 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of 80 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -20 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -30 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -40 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -50 degrees may be less than 10%, less than 5% or less than 2%
  • transmission percentage at an angle of -60 degrees may be less than 10%, less than 5% or less than 2%
  • the transmission profile of the light control film may have a peak transmission at a viewing angle having a magnitude between about 10 degrees and about 30 degrees.
  • an average transmission percentage across the profile may be equal to 50% or less of the peak transmission (i.e., the peak transmission percentage).
  • the structured first major surface may include a plurality of structures separated by one or more grooves extending in a thickness direction of the light control film (having a height above the film).
  • each structure may include a first side surface opposite a second side surface.
  • each groove of the one or more grooves may have one or more substantially planar landings which join the side surfaces of two corresponding, adjacent structures (i.e., that is, a first side surface of one structure facing the second side surface of a second, adjacent structure, the first side surface and the facing second side surface connected by the landing of a groove).
  • the first side surface may be substantially orthogonal with a first adjacent landing of the one or more landings, and the second side surface may make an angle of greater than about 95 degrees with a second adjacent landing of the one or more landings.
  • the directional first etching process and the directional second etching process may be the same process. In other embodiments, the directional first etching process and the directional second etching process may be different processes.
  • the method of making a light control film may further include covering and substantially planarizing the structured first major surface with a planarizing overcoat.
  • the planarizing overcoat covering comprises an optically clear adhesive.
  • the planarizing overcoat may include a polymerizable resin (e.g., it may be the same polymerizable resin used to make the structured surface, described elsewhere herein).
  • a refractive index of the planarizing overcoat may be different from a refractive index of a material comprising the first major surface by greater than about 0.07.
  • a refractive index of the planarizing overcoat may be substantially the same as a refractive index of a material comprising the first major surface (e.g., the two materials may be or include substantially the same material).
  • the cover layer may be light absorbing.
  • the light absorbing cover layer may include a poly electrolyte.
  • the light absorbing cover layer may include a plurality of light absorbing particles.
  • the light absorbing particles may include one or more of a dye, a pigment, and a carbon black.
  • the light absorbing cover layer may have an optical density, at one or more wavelengths from 100 nm to 1 mm, of greater than about 0.1, or greater than about 0.2, or greater than about 0.4, or greater than about 0.6, or greater than about 0.8, or greater than about 1, or greater than about 1.1, or greater than about 1.2, or greater than about 1.3, or greater than about 1.4, or greater than about 1.5, or greater than about 2, or greater than about 2.5, or greater than about 3, or greater than about 3.5, or greater than about 4, or greater than about 4.5, or greater than about 5, or greater than about 5.5, or greater than about 6.
  • the first inorganic particles of the first light transmissive layer may be dispersed in a polymeric binder at the weight loading of the first inorganic particles of greater than about 15%.
  • one of the polymeric binder and the plurality of first inorganic particles may include a plurality of positively charged ionic groups, and the other one of the polymeric binder and the plurality of first inorganic particles may include a plurality of negatively charged ionic groups.
  • the polymeric binder may include one or more of poly(ethylenimine) (PEI), poly(allylamine hydrochloride), polyvinylamine, chitosan, polyaniline, polyamidoamine, poly(vinylbenzyltriamethylamine), polydiallyldimethylammonium chloride (PDAC), poly(dimethylaminoethyl methacrylate), poly(methacryloylamino)propyl-trimethylammonium chloride, poly(vinyl sulfate), poly(vinyl sulfonate), poly( acrylic acid) (PAA), poly(methacrylic acid), poly(styrene sulfonate), dextran sulfate, heparin, hyaluronic acid, carrageenan, carboxymethylcellulose, alginate, sulfonated tetrafluoroethylene based fluoropolymers, poly(vinylphosphoric acid), poly(vinylphosphoric acid
  • each groove 15 may have a substantially planar landing 16, which connects the first side surface 20 of one structure 10 with a second side surface 25 of an adjacent structure 10.
  • each structure 10 may also have a substantially planar top surface 18.
  • Planar landings 16, as well as planar top surfaces 18, may be substantially uncovered by cover layer 30 (no more than 30% of the surfaces covered by cover layer 30).
  • first side surface 20 may be substantially orthogonal (see 01) with a first adjacent landing 16.
  • second side surface 25 may make an angle 02 with a second adjacent landing 16.
  • the angle 02 may be greater than at least about 95 degrees (i.e., second side surface 25 is inclined from the normal to the landing 16, and at a non-zero angle to first side surface 20).
  • FIG. 2 provides an alternate, top view of the embodiment of light control film 100 of FIG. 1 A (see top image of FIG.2, compared against the side view shown as the bottom image of FIG. 2).
  • This top view is provided to illustrate that, in some embodiments, structures 10 may extend across a width direction (e.g., the y-direction shown in FIG. 2, top) and may be arranged along a length direction (e.g., the x-direction shown in FIG. 2, top).
  • the description and function elements shown in FIG. 2 are identical to their like-numbered components in FIGS. 1A-1C, and, accordingly, no additional description is supplied.
  • FIGS. 3A-3B illustrate alternate embodiments of a display system 300a, 300b having light control film 100, according to the present description.
  • display system 300a includes a display 70 configured to generate an image 71 for viewing by the eye of a viewer 80, disposed between an extended light source 75 (e.g., a backlight) and light control film 100.
  • extended light source 75 e.g., a backlight
  • light 50 is emitted by extended light source 75 and passes through display 70, creating image rays 73.
  • image rays 73 are then incident on light control film 100.
  • Those image rays 73 that are incident on the cover layer of a first side surface or a second side surface see surfaces 20 and 25 in FIG.
  • light control film 100 may be instead disposed between extended light source 75 and display 70.
  • light rays 50 are emitted by extended light source 75 but are only transmitted toward the display if light rays 50 are aligned with the first and second side surfaces of light control film 100 (that is, if the light rays 50 pass through without being incident on the light-absorbing cover layer 30 of the first and second side surfaces).
  • light rays 50a are incident on one of the first and second side surfaces are substantially absorbed by the cover layer on these surfaces and is not substantially transmitted through the light control film 100.
  • the light being sent to display 70 is already asymmetric relative to physical axis 301.
  • FIG. 4 is a plot of a light transmission profile for an embodiment of a light control film with an asymmetric transmission profile, such as light control film 100 of FIG. 1A.
  • FIG.4 shows plots of 4 different sample light control films created using the methods described herein.
  • the transmission profile of the light control film (plotted against the viewing angle, or “polar angle” as shown in FIG. 4) has a peak transmission 60 at a viewing angle having a magnitude greater than or equal to about 10 degrees, and an average transmission percentage across the profile equal to 50% or less of the peak transmission.
  • the sample light control films show a peak transmission percentage between about (0.55) 55% and (0.60) 60% at a viewing/polar angle of about +17 degrees.
  • FIGS. 5A-5B illustrate embodiments of a light control film featuring louvers/side surfaces with a multilayer construction, according to the present description. Looking at FIGS. 5 A and 5B together, an alternate embodiment of a light control film is shown.
  • the cover film 30 of light control film 100a may be a multilayer construction, having a core layer 30c Ore sandwiched between a first, inner cladding layer 30 c iadi and a second, outer cladding layer 30 cia d2.
  • This type of construction can be used to prevent unwanted reflections from the cover layer on the side surfaces.
  • High aspect ratio louvers (such as the louvers created by the light absorbing cover layer on the first and second side surfaces in the light control film described herein) preferably have a relatively high extinction coefficient in order to efficiently absorb light in a thin layer. This high extinction coefficient can produce a reflective, metal-like interface with the transmissive regions of the light control film (the areas between side surfaces within the light control film).
  • This multilayer construction with an inner cladding layer, a core layer, and an outer cladding layer, can be formed on the sidewalls by depositing the layers over the (e.g., entire) structured surface and then removing the layers from the planar surfaces (such as the planar landing 16 and planar top surface 18 of FIG. 1A) by selectively (e.g., anisotropically) etching the layer from these layers.
  • the cover layer (including inner cladding layer 30 c iadi, core layer 30 core , and outer cladding layer 30 cia d2) on the first side surface 20 are minimally etched because the first side surface 20 is substantially orthogonal relative to the landing 16 and the primary direction of the etching process. However, as second side surface 25 is at an increased angle to landing 16, the directional etching process will etch the second side surface 25 more than the first side surface 20. As shown in FIG. 5B, the difference in thicknesses T1 and T2, while still applying to the overall cover layer 30 on the first 20 and second 25 side surfaces, may be more specifically applied to the difference in thicknesses between the outer cladding layer 30 cia d2 on each side surface.
  • the outermost layer of the second side surface 25, whether it is only a unitary, single cover layer or the outermost cladding layer of a cover layer having the multilayer construction in FIGS. 5A and 5B, will be subjected more to the effects of the etching process than the same layers on the first side surface 20.
  • outer cladding layer 30 cia d2 may be subjected more directly to the directional first etching process used to remove cover layer from the planar surfaces, this layer may be applied with a greater initial thickness than inner cladding layer 30 cia di (as shown in FIGS. 5A and 5B).
  • the thickness of these layers should be substantially the same on the second side surface 25 as they are on the first side surface 20.
  • FIGS. 6A-6C illustrate embodiments of a light control film featuring louvers/side surfaces with a cover layer and a light transmissive layer, according to the present description. Many of the elements shown in FIGS. 6A-6C share reference numbers with their corresponding elements in the embodiment of FIGS. 1 A-1C and are assumed to have the same function as described for those figures, unless specifically stated otherwise.
  • cover layer 30 may be either a single layer cover layer, such as that shown in FIGS. 1A-1C, or a multilayer construction having a cladding-core-cladding structure as shown in FIGS. 5A-5B.
  • cover layer 30 should be assumed to apply equally to either architecture.
  • a light transmissive layer 35 is disposed on top of cover layer 30, facing the interior of each groove 15, a light transmissive layer 35 is disposed.
  • this light transmissive layer 35 may include a plurality of first inorganic particles at a volume loading of greater than about 5%, as further detailed elsewhere herein.
  • Light transmissive layer 35 acts as an “etch stop” layer to prevent etching of the underlying cover layer 30 that is on the side surfaces. Because of this, it is the light transmissive layer 35 that is exposed to the directional first etching process, such that, as shown in FIG.
  • the light transmissive layer 35 on first side surface 20 has an average thickness T3
  • the light transmissive layer 35 on the second side surface 25 has an average thickness T4, such that T3 is greater than T4 (i.e., the light transmissive layer 35 on second side surface 25 has been at least partially etched by the directional first etching process).
  • FIGS. 7A-7B illustrate one method of making a light control film, according to the present description.
  • the method of making a light control film includes subprocesses (A), (B), (C), and (D).
  • subprocess (A) a substantially light transmissive film 110 is provided.
  • light transmissive film 110 may include a structured first major surface and an opposing second major surface.
  • the structured first major surface may include a plurality of structures 10 separated by grooves 15.
  • Each groove 15 may have a substantially planer landing 16 joining the sides of adjacent structures, and, in some embodiments, each structure 10 may have a substantially planar top surface 18.
  • Each structure has a first side surface 20, which is substantially orthogonal to a first adjacent landing 16, and a second side surface 25, which makes an angle greater than about 95 degrees with a second adjacent landing.
  • the structured first major surface is coated with a cover layer 30a, which covers the first 20 and second 25 side surfaces of structures 10, as well as planar landings 16 and planar top surfaces 18.
  • the cover layer 30a is etched using a directional first etching process 120 to remove the cover layer 30a from more than about 70% of the one or more landings 16 but less than about 30% of each of the first and second side surfaces, creating cover layer 30 that exists primarily on the first 20 and second 25 side surfaces.
  • the remaining cover layer on the first side surface 20 has a first average thickness Tl
  • the remaining cover layer 30 coated on the second side surface has a second average thickness T2, such that Tl is greater than T2.
  • subprocess (D) may include covering and substantially planarizing the structured first major surface with a planarizing overcoat 17.
  • FIG. 7B provides an alternate embodiment (B2) of subprocess (B) from FIG. 7A.
  • cover layer 30 is deposited as a three-layer structure including an inner cladding layer 30ciadi, a core layer 30c Ore , and an outer cladding layer 30 c iad2, as described elsewhere herein.
  • the outermost cladding layer 30ciad2 may be applied thicker than innermost cladding layer 30 c iadi, as the outermost cladding layer will be subjected to the directional etching process more directly.
  • FIG. 8 illustrates an alternate method of making a light control film, according to the present description.
  • this alternate method of making a light control film includes subprocesses (A), (B), (C), (D), (E), and (F).
  • the resulting film was cured using two sequential banks of Fusion D lamps both at 100% power.
  • the protrusions of the microstructured film are a negative replication of the grooves of the tool.
  • the channels of the microstructured film are a negative replication of the uncut portions of the tool between the grooves.
  • a microstructured film was prepared as described in “Method to Make Microstructured Film (Step 1)”

Landscapes

  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Mathematical Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Laminated Bodies (AREA)

Abstract

L'invention concerne un film de commande de lumière qui comprend une première surface principale ayant des structures s'étendant dans le sens de l'épaisseur du film. Les structures sont séparées par des rainures et chaque structure comporte une première surface latérale opposée à une seconde surface latérale. Chaque rainure comporte un palier plan joignant les structures. La première surface latérale est sensiblement orthogonale à un premier palier et la seconde surface latérale forme un angle plus grand qu'environ 95 degrés avec un second palier. Au moins 70 % des surfaces latérales et au plus 30 % des paliers sont revêtus d'une couche de recouvrement. La couche de recouvrement sur les première et seconde surfaces latérales est revêtue d'une couche de transmission de lumière. La couche de transmission de lumière revêtue sur la première surface latérale présente une première épaisseur moyenne T3, et la couche de transmission de lumière revêtue sur la seconde surface latérale présente une seconde épaisseur moyenne T4, de telle sorte que T3 > T4.
PCT/IB2024/062664 2023-12-20 2024-12-13 Film de commande de lumière ayant un profil de transmission asymétrique comprenant une couche de transmission de lumière Pending WO2025133865A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US202363612491P 2023-12-20 2023-12-20
US63/612,491 2023-12-20

Publications (1)

Publication Number Publication Date
WO2025133865A1 true WO2025133865A1 (fr) 2025-06-26

Family

ID=94227822

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2024/062664 Pending WO2025133865A1 (fr) 2023-12-20 2024-12-13 Film de commande de lumière ayant un profil de transmission asymétrique comprenant une couche de transmission de lumière

Country Status (1)

Country Link
WO (1) WO2025133865A1 (fr)

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4601861A (en) 1982-09-30 1986-07-22 Amerace Corporation Methods and apparatus for embossing a precision optical pattern in a resinous sheet or laminate
US20060104084A1 (en) * 2004-11-18 2006-05-18 Hiroyuki Amemiya View angle controlling sheet and liquid crystal display apparatus using the same
US20090115943A1 (en) * 2007-11-07 2009-05-07 3M Innovative Properties Company Low birefringence light control film and methods of making
US8012567B2 (en) 2006-01-12 2011-09-06 3M Innovative Properties Company Light-collimating film
US8234998B2 (en) 2006-09-08 2012-08-07 Massachusetts Institute Of Technology Automated layer by layer spray technology
US8460568B2 (en) 2008-12-30 2013-06-11 3M Innovative Properties Company Method for making nanostructured surfaces
US9063284B2 (en) * 2009-06-18 2015-06-23 3M Innovative Properties Company Light control film
WO2019118685A1 (fr) 2017-12-13 2019-06-20 3M Innovative Properties Company Film de commande de lumière à haute transmission
US10926289B2 (en) 2015-10-12 2021-02-23 3M Innovative Properties Company Layer-by-layer coating apparatus and method
US20210333624A1 (en) 2018-08-01 2021-10-28 3M Innovative Properties Company High transmission light control film
CN113950634A (zh) * 2019-06-12 2022-01-18 3M创新有限公司 具有非对称光输出的高透射率光控膜
US20230028958A1 (en) * 2019-12-23 2023-01-26 3M Innovative Properties Company High transmission light control film

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4601861A (en) 1982-09-30 1986-07-22 Amerace Corporation Methods and apparatus for embossing a precision optical pattern in a resinous sheet or laminate
US20060104084A1 (en) * 2004-11-18 2006-05-18 Hiroyuki Amemiya View angle controlling sheet and liquid crystal display apparatus using the same
US8012567B2 (en) 2006-01-12 2011-09-06 3M Innovative Properties Company Light-collimating film
US8234998B2 (en) 2006-09-08 2012-08-07 Massachusetts Institute Of Technology Automated layer by layer spray technology
US20090115943A1 (en) * 2007-11-07 2009-05-07 3M Innovative Properties Company Low birefringence light control film and methods of making
US8460568B2 (en) 2008-12-30 2013-06-11 3M Innovative Properties Company Method for making nanostructured surfaces
US9063284B2 (en) * 2009-06-18 2015-06-23 3M Innovative Properties Company Light control film
US10926289B2 (en) 2015-10-12 2021-02-23 3M Innovative Properties Company Layer-by-layer coating apparatus and method
WO2019118685A1 (fr) 2017-12-13 2019-06-20 3M Innovative Properties Company Film de commande de lumière à haute transmission
US20210333624A1 (en) 2018-08-01 2021-10-28 3M Innovative Properties Company High transmission light control film
CN113950634A (zh) * 2019-06-12 2022-01-18 3M创新有限公司 具有非对称光输出的高透射率光控膜
US20230028958A1 (en) * 2019-12-23 2023-01-26 3M Innovative Properties Company High transmission light control film

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
KROGMAN ET AL., AUTOMATED PROCESS FOR IMPROVED UNIFORMITY AND VERSATILITY OF LAYER-BY-LAYER DEPOSITION, vol. 23, 2007, pages 3137 - 3141

Similar Documents

Publication Publication Date Title
US12493208B2 (en) High transmission light control film
US12372693B2 (en) High transmission light control film
US11947135B2 (en) High transmission light control film
US20250271601A1 (en) High transmission light control films with asymmetric light output
US20250067914A1 (en) Light control film
CN114846369B (zh) 高透射率光控膜
TW201527787A (zh) 包含第一微結構層及塗層之微結構漫射體、光學堆疊、以及方法
US20250130352A1 (en) Coated microstructured films, methods of making same, and methods of making light control films
WO2025133865A1 (fr) Film de commande de lumière ayant un profil de transmission asymétrique comprenant une couche de transmission de lumière
WO2025133864A1 (fr) Film de commande de lumière à profil de transmission asymétrique
US20240210600A1 (en) Optical System Including Light Control Film and Fresnel Lens
WO2025012837A1 (fr) Film de commande de lumière et son procédé de fabrication
US20250237793A1 (en) Coated microstructured films and methods of making same
WO2024121757A1 (fr) Film de commande de lumière avec arrêt de gravure nanostructuré aléatoire

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 24834867

Country of ref document: EP

Kind code of ref document: A1