Light control film and method of making same

Abstract

A light control film includes a structured first major surface opposite a second major surface. The structured first major surface includes alternating first and second facets. Each of the first facets makes an average first angle of less than 90 degrees with the second major surface. Each of the second facets makes an average second angle of greater than 60 degrees with the second major surface. At least 80% of each of the facets is coated with a light transmissive layer having an average thickness of greater than 0.005 microns and having inorganic particles at a volume loading of greater than 5% on each of the second facets and at most 30% on each of the first facets coated with a cover layer. The light transmissive layer is coated on the first and second facets having respective arithmetic average surface roughnesses Ra1 and Ra2, such that Ra1 > Ra2.

Description

[0001] LIGHT CONTROL FILM AND METHOD OF MAKING SAME Summary In some aspects of the present description, a light control film is provided, the light control film including a structured first major surface opposite a second major surface. The structured first major surface includes a plurality of alternating first and second facets. Each of the first facets makes an average first angle of less than about 90 degrees with the second major surface, and each of the second facets makes an average second angle of greater than about 60 degrees with the second major surface. At least 80% of each of the first and second facets is coated with a light transmissive layer having an average thickness of greater than about 0.005 microns and having a plurality of first inorganic particles at a volume loading of greater than about 5%. At least 70% of the light transmissive layer on each of the second facets and at most 30% of the light transmissive layer on each of the first facets is coated with a cover layer. The light transmissive layer coated on the first and second facets may have respective arithmetic average surface roughnesses Ra1 and Ra2, such that Ra1 is greater than Ra2. In some aspects of the present description, a light control film is provided, the light control film including a light transmissive body having a plurality of alternating linear first and second facets, a light transmissive layer, and a light absorbing cover layer. The light transmissive layer has an average thickness of greater than about 0.005 microns and is coated on at least 80% of each of the first and second facets. The light transmissive layer includes a plurality of first inorganic particles at a volume loading of greater than about 5%. The light absorbing cover layer has an average thickness of greater than about 0.05 microns and is coated on at least 70% of the light transmissive layer on each of the second facets and on at most 30% of the light transmissive layer on each of the first facets. For each of at least a majority of the second facets, the light absorbing cover layer coated on the second facet extends along a thickness direction of the light control film to within at least the average thickness of the light transmissive layer from the first facet adjacent to the second facet. In some aspects of the present description, a method of making a light control film is provided, the method including providing a substantially light-transmissive film having a structured first major surface and an opposing second major surface, the structured first major surface having a plurality of alternating first and second facets, coating the structured first major surface with a light- transmissive layer to reduce an etch rate of the first and second facets by at least 20%, coating the light transmissive layer with a cover layer so that at least 80% of the light transmissive layer is covered by the cover layer, and etching the cover layer using the directional first etching process to remove more than about 80% of the cover layer from each first facet but less than about 40% of the cover layer from each second facet, resulting in the light transmissive layer coated on the first and second facets having respective arithmetic average surface roughnesses Ra1 and Ra2, such that Ra1 > Ra2. Each of the first facets makes an average first angle of less than about 90 degrees with the second major surface, and each of the second facets makes an average second angle of greater than about 60 degrees with the second major surface. Coating the structured first major surface with a light transmissive layer reduces an etch rate of the first and second facets by at least 20% when using a same directional first etching process. The light transmissive layer covers at least 80% of each of the first and second facets and includes a plurality of first inorganic particles at a volume loading of greater than about 5%. Coating the light transmissive layer with a cover layer provides that at least 80% of the light transmissive layer is covered by the cover layer. In some aspects of the present description, a light control film is provided, the light control film including a light transmissive body, a first light transmissive layer, a light absorbing cover layer, and a planarizing overcoat. The light transmissive body includes a plurality of alternating linear first and second facets extending along a first direction and arranged along a different second direction. The first light transmissive layer has a first average thickness of greater than about 0.005 microns and less than about 0.5 microns, and is coated on at least 80% of each of the first and second facets. The light transmissive layer includes a plurality of first inorganic particles with a first inorganic material. The light absorbing cover layer has an average thickness of greater than about 0.05 microns and is coated on at least 70% of the light transmissive layer on each of the second facets and on at most 30% of the light transmissive layer on each of the first facets. The planarizing overcoat covers the light absorbing cover layer and substantially planarizes the structured first major surface. For each of at least some of the first and second facets, a second light transmissive layer is disposed between the planarizing overcoat and the light absorbing cover layer that covers the facet. The second light transmissive layer includes the first inorganic material and has a second average thickness that is less than about 20 nm. Brief Description of the Drawings FIGS.1A-1C provide side, cross-sectional views of a light control film, in accordance with an embodiment of the present description; FIGS.2A-2B provide additional details for a light control film, in accordance with an embodiment of the present description; FIG.3 presents contrasting top and side profile views of a light control film, in accordance with an embodiment of the present description; FIG.4 illustrates light transmission paths for a light control film, in accordance with an embodiment of the present description; FIGS.5A-5B show embodiments of light transmissive and cover layers of a light control film, in accordance with an embodiment of the present description; FIGS.6A-6E illustrate display systems including a light control film, in accordance with an embodiment of the present description; FIG.7 illustrates a method of making a light control film, in accordance with an embodiment of the present description; FIG.8 includes a microscope image of a light control film, in accordance with an embodiment of the present description; and FIG.9 illustrates the light control film test construction for adhesion testing related to the experimental examples. Detailed Description In the following description, reference is made to the accompanying drawings that form a part hereof and in which various embodiments are shown by way of illustration. The drawings are not necessarily to scale. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present description. The following detailed description, therefore, is not to be taken in a limiting sense. Etch stops (also known as etch masks or hard masks) are ubiquitous in microelectronics manufacturing where they allow for termination of an etching process to a controlled depth. Etch stops can function in wet and / or dry etching processes. The etch stops for dry etching (e.g., reactive ion etching, or RIE) are typically inorganic coatings (e.g., oxides or nitrides) and would typically comprise a continuous inorganic layer, as opposed to a layer of discrete inorganic nanoparticles. According to some aspects of the present description, the layer-by-layer (LbL) coating method (a liquid phase coating method) is used to deposit dry etch stops comprising inorganic oxide particles and oppositely charged polymers, or two oppositely charged inorganic oxide particles. LbL deposition involves the sequential assembly of at least two different materials with binding groups, which are complementary to each other (e.g., oppositely charged functional groups or H-bond donor and acceptors groups, etc.). This coating method can provide very high loadings of inorganic particles (of various shapes and sizes), for example loadings of greater than or equal to 25 wt%, greater than or equal to 50 wt%, greater than or equal to 75 wt%, greater than or equal to 90 wt%, or greater than or equal to 99 wt%, as can be measured by thermogravimetric analysis (TGA). Likewise, very high- volume loadings of inorganic particles can be achieved, for example loadings of greater than or equal to 10 vol%, greater than or equal to 25 vol%, greater than or equal to 50 vol%, greater than or equal to 75 vol%, as can be measured by scanning electron microscopy (SEM) and / or transmission electron microscopy (TEM). The coatings may also be porous, especially when spherical nanoparticles are used. It is unexpected that a porous and / or organic-containing composite coating could function as an effective dry etch stop. Relevant inorganic materials for the etch stops of the present description may include metal oxide nanoparticles such as silicon dioxide (silica), aluminum oxide (alumina), zirconium oxide (zirconia), titanium dioxide (titania), and the like. Other relevant metal oxides include clay platelets, such as aluminosilicates (e.g., montmorillonite, vermiculite, and the like) or lithium magnesium silicates (e.g., LAPONITE®). Still more relevant inorganic materials include MXenes, as well as sulfide or nitride particles. Metal nanoparticles and platelets are also in scope. Some inorganic materials possess binding groups (e.g., charged functional groups) on their unmodified surfaces, while others may require surface modification. Relevant organic binder materials for the etch stops of this invention include charged polymers (i.e., polyelectrolytes). These polymers can be water soluble or can be water insoluble, but stable in water as emulsions, dispersions, or suspensions. The polymers must possess binding groups (e.g., charged functional groups), either as part of the polymer backbone or side chains, or through surface modification by a charged surfactant. Typical negatively charged groups may include, for example, carboxylate, sulfonate, phosphate, or phosphonate groups, while typical positively charged groups may include, for example, primary, secondary, or tertiary amines, and quaternary ammonium groups. Compared to classic dry etch stops deposited via vacuum deposition, LbL-deposited etch stops have the benefit of not requiring a vacuum chamber. Vacuum chambers require time for pump down and also can complicate web handling. In addition, it has been shown that LbL-deposited etch stops such as those described herein can surprisingly provide superior adhesion to certain polymer resins compared to standard etch stops (e.g., those deposited by plasma-enhanced chemical vapor deposition, or PE-CVD). According to some aspects of the present description, a light control film includes a structured first major surface opposite a second major surface, the structured first major surface having a plurality of alternating first and second facets. In some embodiments, each of the first facets may make an average first angle of less than about 90 degrees, or less than about 85 degrees, or less than about 80 degrees, or less than about 75 degrees, or less than about 70 degrees, or less than about 65 degrees, or less than about 60 degrees, or less than about 55 degrees, or less than about 50 degrees, or less than about 45 degrees, or less than about 40 degrees, or less than about 35 degrees, or less than about 30 degrees, or less than about 25 degrees, or less than about 20 degrees, or less than about 15 degrees, or less than about 10 degrees, or less than about 5 degrees with the second major surface. In some embodiments, each of the second facets may make an average second angle of greater than about 60 degrees, or greater than about 65 degrees, or greater than about 70 degrees, or greater than about 75 degrees, or greater than about 80 degrees, or greater than about 85 degrees, or greater than about 90 degrees, or greater than about 95 degrees, or greater than about 96 degrees, or greater than about 97 degrees, or greater than about 98 degrees, or greater than about 99 degrees with the second major surface. In some embodiments, the light control film may further include a light transmissive body having the structured first major surface and the opposite second major surface. In some embodiments, the light control film may be curved along at least one direction. In some embodiments, at least 80%, or at least 85%, or at least 90%, or at least 95% of each of the first and second facets may be coated with a light transmissive layer having an average thickness of greater than about 0.005 microns, or greater than about 0.01 microns, or greater than about 0.02 microns, or greater than about 0.03 microns, or greater than about 0.04 microns, or greater than about 0.05 microns, or greater than about 0.08 microns, or greater than about 0.1 microns, or greater than about 0.15 microns, or greater than about 0.2 microns and including a plurality of first inorganic particles at a weight loading of greater than about 15%, or greater than about 20%, or greater than about 25%, or greater than about 30%, or greater than about 40%, or greater than about 50%, or greater than about 60%, or greater than about 70%, or greater than about 80%, or greater than about 90%, or greater than about 95%, or greater than about 96%, or greater than about 97%, or greater than about 98%, or greater than about 99%. In some embodiments, the light transmissive layer may have an average thickness of less than about 0.5 microns. In some embodiments, the light transmissive layer may have an average thickness in a range of between about 0.005 microns and about 0.500 microns, or between about 0.01 microns and about 0.400 microns, or between about 0.03 microns and about 300 microns and may include a plurality of first inorganic particles at a weight loading of from about 15% to about 99%, or from about 20% to about 80%, or from about 25% to about 70%. In some embodiments, the light transmissive layer may have an average thickness in a range of between about 0.005 microns and about 0.500 microns, or between about 0.01 microns and about 0.400 microns, or between about 0.03 microns and about 300 microns, and may include a plurality of first inorganic particles at a volume loading of from about 5% to about 95%, or from about 5% to about 80%, or from about 5% to about 70%, or from about 7% to about 70%, or from about 10% to about 70%. In some embodiments, the inorganic particles in the light transmissive layer may be spherical, aspherical, oblong, or platelets, or any other appropriate shape. In some embodiments, the particles may be non-aggregated, individual particles, loose aggregates of individual particles, or permanent aggregates of primary particles. In some embodiments, the particles may be amorphous, crystalline, or semi-crystalline. In some embodiments, the first inorganic particles may be sputtered particles which enter a vapor phase as atoms or small atom clusters which may then be redeposited as an integral material layer. In the case of spherical inorganic particles, typical primary / individual particle diameters may range from about 1 nm to about 190 nm, or from about 1 nm to about 75 nm, or from about 1 nm to about 50 nm. In the case of non-spherical particles, the longest dimension would typically range from about 4 nm to about 3000 nm, or from about 4 nm to about 1000 nm, or from about 4 nm to about 500 nm, or from about 4 nm to about 250 nm, or from about 4 nm to about 75 nm. In the case of platelets, they may be fully or partially exfoliated with aspect ratios less than about 3000:1, or less than about 1000:1, or less than about 500:1, or less than about 250:1, or less than about 50:1. In some embodiments, platelets may have an aspect ratio greater than about 5:1. The particle size (e.g., diameter or longest dimension) of the inorganic particles in the light transmissive layer can be measured by scanning electron microscopy (SEM) or transmission electron microscopy (TEM), for example. In some embodiments, the particle size distribution of the inorganic particles in the light transmissive layer may be, for example, monodisperse, polydisperse, multimodal (e.g., bimodal, or trimodal). Various embodiments may include mixtures of the different types of particles described above. In some embodiments, at least about 70%, or at least about 75%, or at least about 80%, or at least about 85%, or at least about 90%, or at least about 95% of the light transmissive layer on each of the second facets, and at most about 30%, or at most about 25%, or at most about 20%, or at most about 15%, or at most about 10%, or at most about 5% of the light transmissive layer on each of the first facets may be coated with a cover layer. In some embodiments, the light transmissive layer may be coated on the first and second facets such that they have respective arithmetic average surface roughnesses Ra1 and Ra2, such that Ra1 is greater than Ra2. In some embodiments, the first inorganic particles may include one or more of silicon dioxide, titanium dioxide, zirconium dioxide, aluminum oxide, and clay platelets. In some embodiments, when the first inorganic particles are clay platelets, the clay platelets may include silicates. In some such embodiments, the silicates may include one or more of aluminum silicates and magnesium silicates. In some embodiments, the first inorganic particles of the light transmissive layer may be dispersed in a polymeric binder at the weight loading of greater than about 15%. In some such embodiments, 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. In some such embodiments, 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(vinylphosphonic acid), polyurethane, and acrylic. An example of a suitable cationic polyurethane polymeric binder is SANCURE 20072 (Lubrizol Corp, Wickliffe, OH). An example of a suitable cationic acrylic polymeric binder is OTTOPOL K-672 (Gellner Industrial, Hometown, PA). In some embodiments, any binder in the light transmission layer may be at a weight loading of not greater than about 20%, or not greater than about 15%, or not greater than about 10%, or not greater than about 5%, or not greater than about 4%, or not greater than about 3%, or not greater than about 2%, or not greater than about 1%. In some embodiments, the light transmission layer may not include any binder. In some embodiments, the light transmissive layer may further include a plurality of second inorganic particles. In some such embodiments, the second inorganic particles may include one or more of silicon dioxide, titanium dioxide, zirconium dioxide, aluminum oxide, and clay platelets. In some embodiments, when the second inorganic particles are clay platelets, the clay platelets may include silicates. In some such embodiments, the silicates may include one or more of aluminum silicates and magnesium silicates. In some embodiments, one of the plurality of first inorganic particles and the plurality of second inorganic particles may include a plurality of positively charged ionic groups, and the other one of the plurality of first inorganic particles and the plurality of second inorganic particles may include a plurality of negatively charged ionic groups. In some embodiments, 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. In some embodiments, the cover layer may have an average thickness of less than about 2000 nm, or less than about 1500 nm, or less than about 1000 nm, or less than about 500 nm, or less than about 400 nm, or less than about 300 nm, or less than about 200 nm, or less than about 100 nm, or less than about 50 nm. In some embodiments, the cover layer may be light absorbing. The cover layer may absorb light at one more wavelengths in the ultraviolet light range (i.e., 100-400 nm) and / or the visible light range (i.e., 400-700 nm) and / or the infrared light range (i.e., 700 nm – 1 mm). In some such embodiments, the light absorbing cover layer may include a plurality of light absorbing particles. In some such embodiments, the light absorbing particles may include one or more of a dye, a pigment, and a carbon black. In some embodiments, 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. In some embodiments, the optical density is less than about 3.0, or less than about 2.5, or less than about 2.0. In some embodiments the optical density is between 0.5 and 2.5, or between 1.0 and 2.0 or between 1.2 and 1.8. As used herein, optical density shall be defined as -log10(T), where T is the optical transmission of the film, and T is defined as Io / It, where Iois the intensity of incident light and Itis the intensity of the transmitted light (light passing through the medium). For example, if transmission, T, is 1%, the optical density is calculated as -log10(0.01) which is equal to an optical density of 2.0. In some embodiments, a layer-by-layer (LbL) coating method, the same method that can be used to deposit the etch stop, is used to deposit the cover layer. In this case, the cover layer would comprise at least one material with a first binding group and a second material with a second binding group, the first binding group and second binding group having complementary interactions. Typically, the first material is a polymer binder (e.g., a polyelectrolyte). The polymer binder may be the same polymer binder present in the etch stop or may be a different polymer. In the case when the cover layer is light-absorbing, the second material would typically be a light-absorbing pigment, dye, or a carbon black comprising binding groups complementary to those in the first material. Suitable pigments include, for example, ionically-modified pigment nanoparticles commercially available as inkjet pigment colorants under the trade designation CAB-O-JET from Cabot Corporation (Boston, MA) such as black, cyan, magenta, and / or yellow pigments, or inkjet pigments from the BONJET Black Series from Orient Corporation of America (Cranford, NJ). In general, pigments or other wavelength-selective light absorbing particles may be functionalized either by being covalently surface modified or non-covalently surface modified, for example, with an ionic surfactant. Some of major classes of dyes / pigments include phthalocyanines, cyanine, transition metal dithioline, squarylium, croconium, quinones, anthraquinones, iminium, pyrylium, thiapyrylium, azulenium, azo, perylene and indoanilines. Many of these dyes and pigments can exhibit visible and / or infrared light absorption as well. Further, many different types of visible dyes and colorants may be used such as acid dyes, azoic coloring matters, coupling components, diazo components. Basic dyes include developers, direct dyes, disperse dyes, fluorescent brighteners, food dyes, ingrain dyes, leather dyes, mordant dyes, natural dyes and pigments, oxidation bases, pigments, reactive dyes, reducing agents, solvent dyes, sulfur dyes, condense sulfur dyes, vat dyes. Some of the organic pigments may belong to one or more of monoazo, azo condensation, insoluble metal salts of acid dyes and disazo, naphthols, arylides, diarylides, pyrazolone, acetoarylides, naphthanilides, phthalocyanines, anthraquinone, perylene, flavanthrone, triphendioxazine, metal complexes, quinacridone, polypryrrolopyrrole etc. Suitable dyes for the cover layer could include, for example, acid dyes or basic dyes; some specific examples include, without limitation, Acid Orange 12, Acid Blue 25, Eriochrome Black T, Lissamine Green B, Acid Fuchsin, Alizarin Blue Black B, Acid Blue 80, Acid Blue 9, Brilliant Blue G, Water Soluble Nigrosin, Methylene Blue, Crystal Violet, Safranin, Basic Fuchsin, and combinations thereof. Note that dyes with just one or a few charged functional groups, for example, may not be suitable as a material for layer-by-layer deposition directly; however, such dyes can be ion exchanged into layer-by-layer coatings as disclosed in WO2023 / 047204 (Schmidt et al.). The light absorbing material in the light-absorbing cover layer may comprise individual dye molecules, aggregates of dye molecules, and / or pigment particles, for example. The pigment or carbon black particles in the light-absorbing cover layer may be spherical, aspherical, oblong, or platelets, for example. The particles may be non-aggregated, individual particles, or they may be loose aggregates of individual particles, or they may be permanent aggregates of primary particles. The particles may be amorphous, crystalline, or semi-crystalline. In the case of spherical particles, typical primary / individual particle diameters range from 1 nm to 190 nm, more preferably from 5 nm to 100 nm. In the case of non-spherical particles, the longest dimension would typically range from 4 nm to 3000 nm, or from 4 nm to 1000 nm, or from 4 nm to 500 nm, or from 4 nm to 250 nm, or from 4 nm to 75 nm. In the case of platelets, they may be fully or partially exfoliated with aspect ratios less than 3000:1, less than 1000:1, less than 500:1, less than 250:1, or less than 50:1. Platelets would typically have an aspect ratio greater than 5:1. The particle size (e.g., diameter or longest dimension) of the particles in the cover layer can be measured by scanning electron microscopy (SEM) or transmission electron microscopy (TEM), for example. The particle size distribution of the particles in the cover layer may be, for example, monodisperse, polydisperse, bimodal, or multimodal (e.g., bimodal or trimodal). Various embodiments may include mixtures of the different types of particles described above. In some embodiments, the cover layer may be a multilayer coating with core clad structure (i.e., may include a core layer disposed between a first cladding layer and a second cladding layer, as described in US Patent No.11,550,183, which is hereby included by reference). In some embodiments, at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% of the first facets are curved. In some embodiments, at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 95% of the second facets are substantially planar. In some embodiments, the first and second facets may be linear facets extending along a length direction of the light control film and arranged along a width direction of the light control film. In some embodiments, at least some of the first facets may be curved. In some embodiments, at least some of the first facets 20 may be substantially planar. In some such embodiments, substantially all first facets 20 may be substantially planar. In some embodiments, at least one of the light transmissive and cover layers may be porous including a plurality of pores. In some such embodiments, a volume fraction of the pores is greater than 0.2, or greater than 0.3, or greater than 0.4, or greater than 0.5, or greater than 0.6, or greater than 0.7. In some embodiments, at least one of the light transmissive and cover layers may be physically discontinuous including a plurality of spaced apart islands. In some embodiments, the light control film may further include a planarizing overcoat covering, and substantially planarizing, the structured first major surface. In some embodiments, a refractive index of the planarizing overcoat may be different from a material of the first and second faces of the structured first major surface by greater than about 0.07, or greater than about 0.09, or greater than about 0.1, or greater than about 0.13, or greater than about 0.15, or greater than about 0.2, or greater than about 0.25. According to some aspects of the present description, a display system may include any of the light control film of the present description disposed on a display configured to form an image, and a second light control film disposed between the light control film and the display. In some embodiments, the second light control film may include a plurality of alternating substantially light transmissive and light absorbing regions (e.g., a louver film such as a micro-louver as shown in US9,063,284 or a nano-louver as shown in US Patent No.11,550,183). In some embodiments, nanolouver films are made via microreplication of a clear channel film, followed by conformal coating (e.g., via layer-by-layer coating) of a light-absorbing layer, followed by selective removal (e.g., via a directional etching process, such as reactive ion etching) of the light absorbing layer from the flats (i.e., horizontal surfaces – substantially parallel to the light input and light output surfaces). In some such embodiments, the second light control film has a relative transmission at a viewing angle of 0 degrees of at least 75%, wherein relative transmission is a percentage of luminance between a reading with the light control film and a reading without the light control film. In some such embodiments, the average thickness of the light absorbing regions of the nanolouver film is less than or equal to about 2.5 microns, or less than or equal to about 2.0 microns, or less than or equal to about 1.5 microns, or less than or equal to about 1.0 microns, or less than or equal to about 0.75 microns, or less than or equal to about 0.50 microns. In some such embodiments, the light absorbing regions of the nanolouver film have an aspect ratio of at least about 50, or at least about 100, or at least about 200, or at least about 300, or at least about 400, or at least about 500, or at least about 600, or at least about 700, or at least about 800, or at least about 900, or at least about 1000, wherein aspect ratio is defined as the height of the light absorbing region divided by the maximum width of the light absorbing region. In some embodiments, the light absorbing regions of the nanolouver film may include polyelectrolytes. In some embodiments, the light absorbing regions of the nanolouver film may include at least 25 wt% or at least 10 vol% of light absorbing particles, or at least 50 wt% or at least 20 vol% of light absorbing particles, or at least 75 wt% or at least 30 vol% of light absorbing particles. In some embodiments, the display system may be curved along at least one direction. In some embodiments, a first bonding layer may bond the light control film to the second light control film, and a second bonding layer may bond the second light control film to the display. In some embodiments, the display system comprises the light control film assembly, first and second light control films, bonded to a transparent lens member with an optically clear adhesive and the display is separated from the light control film by an air gap. According to some aspects of the present description, a light control film may include a light transmissive body having a plurality of alternating linear first and second facets, a light transmissive layer, and a light absorbing layer. In some embodiments, the light transmissive layer may have an average thickness of greater than about 0.005 microns, or greater than about 0.01 microns, or greater than about 0.02 microns, or greater than about 0.03 microns, or greater than about 0.04 microns, or greater than about 0.05 microns, or, greater than about 0.08 microns, or greater than about 0.1 microns, or greater than about 0.15 microns, or greater than about 0.2 microns and may be coated on at least 80%, or at least 85% or at least 90%, or at least 95% of each of the first and second facets. In some embodiments, the light transmissive layer may include a plurality of first inorganic particles at a weight loading of greater than about 15%, or greater than about 20%, or greater than about 25%, or greater than about 30%, or greater than about 40%, or greater than about 50%, or greater than about 60%, or greater than about 70%, or greater than about 80%, or greater than about 90%, or greater than about 95%, or greater than about 96%, or greater than about 97%, or greater than about 98%, or greater than about 99%. In some embodiments, the light transmissive layer has an average thickness of less than about 0.500 microns. In some embodiments, the light transmissive layer has an average thickness in a range of between 0.005 microns and 0.500 microns, or from 0.01 microns to 0.400 microns, or from about 0.03 microns to about 300 microns and including a plurality of first inorganic particles at a weight loading of from about 15% to 99%, or from 20% to 80%, or from 25% to 70%. In some embodiments, the light transmissive layer has an average thickness in a range of between 0.005 microns and 0.500 microns, or from 0.01 microns to 0.400 microns, or from about 0.03 microns to about 300 microns and including a plurality of first inorganic particles at a volume loading of from about 5% to 95%, or from about 5% to 80%, or from 5% to 70%, or from 10% to 70%. In some embodiments, the light absorbing 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 and may be coated on 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 light transmissive layer on each of the second facets and on 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 light transmissive layer on each of the first facets. In some embodiments, the cover layer may have an average thickness of from about 0.05 microns to 1.5 microns, or from about 0.10 microns to 1.0 microns, or from about 0.20 microns to 0.50 microns and may be coated on 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 light transmissive layer on each of the second facets and on 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 light transmissive layer on each of the first facets. In some embodiments, for each of at least a majority of the second facets, the light absorbing layer coated on the second facet may extend along a thickness direction (e.g., a z-axis) of the light control film to within at least the average thickness of the light transmissive layer from the first facet adjacent to the second facet. According to some aspects of the present description, a method of making a light control film may include the steps of providing a substantially light transmissive film having a structured first major surface and an opposing second major surface, the structured first major surface having a plurality of alternating first and second facets, each of the first facets making an average first angle of less than about 90 degrees, or less than about 85 degrees, or less than about 80 degrees, or less than about 75 degrees, or less than about 70 degrees, or less than about 65 degrees, or less than about 60 degrees, or less than about 55 degrees, or less than about 50 degrees, or less than about 45 degrees, or less than about 40 degrees, or less than about 35 degrees, or less than about 30 degrees, or less than about 25 degrees, or less than about 20 degrees, or less than about 15 degrees, or less than about 10 degrees, or less than about 5 degrees with the second major surface, each of the second facets making an average second angle of greater than about 60 degrees, or greater than about 65 degrees, or greater than about 70 degrees, or greater than about 75 degrees, or greater than about 80 degrees, or greater than about 85 degrees, or greater than about 90 degrees, or greater than about 95 degrees, or greater than about 96 degrees, or greater than about 97 degrees, or greater than about 98 degrees, or greater than about 99 degrees with the second major surface; coating the structured first major surface with a light transmissive layer to reduce an etch rate of the light transmissive body (i.e., the body including the first and second facets) by at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80% when using a same directional first etching process, the light transmissive layer covering at least 80%, or at least 85% or at least 90%, or at least 95% of each of the first and second facets and including a plurality of first inorganic particles at a weight loading of greater than about 15%, or greater than about 20%, or greater than about 25%, or greater than about 30%, or greater than about 40%, or greater than about 50%, or greater than about 60%, or greater than about 70%, or greater than about 80%, or greater than about 90%, or greater than about 95%, or greater than about 96%, or greater than about 97%, or greater than about 98%, or greater than about 99%; coating the light transmissive layer with a cover layer so that at least 80%, or at least 85% or at least 90%, or at least 95% of the light transmissive layer is covered by the cover layer; and etching the cover layer using the directional first etching process to remove more than about 80%, or more than about 85%, or more than about 90%, or more than about 95%, or more than about 98%, or more than about 99% of the cover layer from each first facet but less than about 40%, or less than about 35%, or 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 the cover layer from each second facet, resulting in the light transmissive layer coated on the first and second facets having respective arithmetic average surface roughnesses Ra1 and Ra2, such that Ra1 > Ra2. According to some aspects of the present description, a light control film includes a light transmissive body having a plurality of alternating linear first and second facets extending along a first direction (e.g., a y-axis) and arranged along a different second direction (e.g., x-axis), a first light transmissive layer, a light absorbing layer, and a planarizing overcoat. In some embodiments, the first light transmissive layer may have a first average thickness of greater than about 0.005 microns, or greater than about 0.01 microns, or greater than about 0.02 microns, or greater than about 0.03 microns, or greater than about 0.04 microns, or greater than about 0.05 microns, or greater than about 0.08 microns, or greater than about 0.1 microns, or greater than about 0.15 microns, or greater than about 0.2 microns and may be coated on at least 80%, or at least 85% or at least 90%, or at least 95% of each of the first and second facets. In some embodiments, the light transmissive layer may include a plurality of first inorganic particles including a first inorganic material (e.g., Si). In some embodiments, the light transmissive layer is disposed on the plurality of alternating first and second facets of the light transmissive body. In some embodiments, the light absorbing 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 and may be coated on 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 light transmissive layer on each of the second facets and on 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 light transmissive layer on each of the first facets. In some embodiments, the cover layer may have an average thickness of from about 0.05 microns to 1.5 microns, or from about 0.10 microns to 1.0 microns, or from about 0.20 microns to 0.50 microns and may be coated on 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 light transmissive layer on each of the second facets and on 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 light transmissive layer on each of the first facets. In some embodiments, the planarizing overcoat may cover the light absorbing cover layer and may substantially planarize the structured first major surface. In some embodiments, for each of at least some of the first and second facets, a second light transmissive layer may be disposed between the planarizing overcoat and the light absorbing layer that cover the facet. In some embodiments, the second light transmissive layer may include the first inorganic material and may have a second average thickness that is less than about 20 nm, or less than about 10 nm, or less than about 5 nm. In some embodiments, the second light transmissive layer may be discontinuous. In some embodiments, the source of this second light transmissive layer may be redeposition during a selective etch step composed of nonvolatile etch byproducts from the first light transmissive layer. Turning now to the figures, FIGS.1A-1C provide side, cross-sectional views of an embodiment of a light control film, according to the present description. FIG.1A shows light control film 300 having a structured first major surface 11 opposite a second major surface 12. In some embodiments, the structured first major surface 11 includes a plurality of alternating first facets 20 and second facets 30. In some embodiments, each of the first facets 20 may make an average first angle θ1 of less than about 90 degrees, or less than about 85 degrees, or less than about 80 degrees, or less than about 75 degrees, or less than about 70 degrees, or less than about 65 degrees, or less than about 60 degrees, or less than about 55 degrees, or less than about 50 degrees, or less than about 45 degrees, or less than about 40 degrees, or less than about 35 degrees, or less than about 30 degrees, or less than about 25 degrees, or less than about 20 degrees, or less than about 15 degrees, or less than about 10 degrees, or less than about 5 degrees with the second major surface 12. In some embodiments, each of the second facets may make an average second angle θ2 of greater than about 60 degrees, or greater than about 65 degrees, or greater than about 70 degrees, or greater than about 75 degrees, or greater than about 80 degrees, or greater than about 85 degrees, or greater than about 90 degrees, or greater than about 95 degrees, or greater than about 96 degrees, or greater than about 97 degrees, or greater than about 98 degrees, or greater than about 99 degrees with the second major surface. In some embodiments, the light control film may include a light transmissive body 10 comprising the structured first major surface 11 and the opposite second major surface 12. In some embodiments, the light control film may have a structured surface 11 such that all prisms are oriented in the same direction across the film where each of the first facets 20 may make an average first angle θ1 of less than about 90 degrees, or less than about 85 degrees, or less than about 80 degrees, or less than about 75 degrees, or less than about 70 degrees, or less than about 65 degrees, or less than about 60 degrees, or less than about 55 degrees, or less than about 50 degrees, or less than about 45 degrees, or less than about 40 degrees, or less than about 35 degrees, or less than about 30 degrees, or less than about 25 degrees, or less than about 20 degrees, or less than about 15 degrees, or less than about 10 degrees, or less than about 5 degrees with the second major surface 12. In some embodiments, each of the second facets may make an average second angle θ2 of greater than about 60 degrees, or greater than about 65 degrees, or greater than about 70 degrees, or greater than about 75 degrees, or greater than about 80 degrees, or greater than about 85 degrees, or greater than about 90 degrees, or greater than about 95 degrees, or greater than about 96 degrees, or greater than about 97 degrees, or greater than about 98 degrees, or greater than about 99 degrees with the second major surface. In some embodiments, such films may include light directing films or light turning films, for example wherein all of the first facets 20 have angles θ1 that are of the same or approximately the same average angle and wherein all of the second facets 30 have angles θ2 that are of the same or approximately the same average angle, but different than θ1. In some embodiments, such as a light turning film, first facets 20 and second facets 30 may define prisms oriented in the same direction across the film (e.g., extending across the film in the y-direction and arranged across the film in the x- direction), where θ1 for all first facets 20 is substantially the same with an average angle of between about 40 degrees and about 70 degrees, and θ2 for all second facets 30 is substantially the same with an average angle between about 80 degrees and about 90 degrees. In some embodiments, the first facets 20 may have angles θ1 in a range of from about 20 degrees to about 70 degrees, or from about 30 degrees to about 70 degrees, or from about 40 degrees to about 70 degrees or from about 50 degrees to about 70 degrees. In some embodiments, the second facets 30 may have average angles θ2 in the range of about 70 degrees to about 90 degrees, or from about 75 degrees to about 90 degrees or from about 80 degrees to about 90 degrees or from about 85 degrees to about 90 degrees. In other embodiments, the light control film 300 may have a structured surface 11 such that all of the prisms are oriented in the same direction across the film where each of the first facets 20 have varying first angles θ1 and second facets 30 have approximately the same average angle θ2 across the film where the varying resulting prisms shapes have a lensing function, where the angles of the first facets 20 may make an average first angle θ1 of less than about 90 degrees, or less than about 85 degrees, or less than about 80 degrees, or less than about 75 degrees, or less than about 70 degrees, or less than about 65 degrees, or less than about 60 degrees, or less than about 55 degrees, or less than about 50 degrees, or less than about 45 degrees, or less than about 40 degrees, or less than about 35 degrees, or less than about 30 degrees, or less than about 25 degrees, or less than about 20 degrees, or less than about 15 degrees, or less than about 10 degrees, or less than about 5 degrees with the second major surface 12. In some embodiments, each of the second facets may make an average second angle θ2 of greater than about 60 degrees, or greater than about 65 degrees, or greater than about 70 degrees, or greater than about 75 degrees, or greater than about 80 degrees, or greater than about 85 degrees, or greater than about 90 degrees, or greater than about 95 degrees, or greater than about 96 degrees, or greater than about 97 degrees, or greater than about 98 degrees, or greater than about 99 degrees with the second major surface. In some embodiments, the varying average first angles θ1 may be between about 70 degrees and about 5 degrees and the average second angles θ2 may be between about 80 degrees and about 90 degrees. In other embodiments, the light control film 300 may be a Fresnel lens (similar to the lens described in application WO 2021 / 090130) where the structured surface 11 has a symmetric varying prism structure where each of the first facets 20 have varying first angles θ1 and θ1’ and second facets 30 have approximately the same average angle θ2 and θ2’ across the film where the varying prism shapes result in a lens (e.g., a Fresnel lens). In some embodiments, the angles of each of the first facets 20 may make an average first angle θ1, θ1’ of less than about 90 degrees, or less than about 85 degrees, or less than about 80 degrees, or less than about 75 degrees, or less than about 70 degrees, or less than about 65 degrees, or less than about 60 degrees, or less than about 55 degrees, or less than about 50 degrees, or less than about 45 degrees, or less than about 40 degrees, or less than about 35 degrees, or less than about 30 degrees, or less than about 25 degrees, or less than about 20 degrees, or less than about 15 degrees, or less than about 10 degrees, or less than about 5 degrees with the second major surface 12. In some embodiments, each of the second facets may make an average second angle θ2, θ2’ of greater than about 60 degrees, or greater than about 65 degrees, or greater than about 70 degrees, or greater than about 75 degrees, or greater than about 80 degrees, or greater than about 85 degrees, or greater than about 90 degrees, or greater than about 95 degrees, or greater than about 96 degrees, or greater than about 97 degrees, or greater than about 98 degrees, or greater than about 99 degrees with the second major surface. In some embodiments, the varying average first angles θ1, θ1’ may be between about 70 degrees and about 5 degrees, and the average first angles of θ1, θ1’ of first facets 20 may be steeper (i.e., have a higher average angle) at the edges of light control film 300 and shallower in the center of light control film 300 (i.e., have a lower average angle), In some embodiments, the average second angles θ2, θ2’ of the second facets 30 of the structured surface 11 are substantially equal across the film with average angles θ2, θ2’ being between about 80 degrees and about 90 degrees. Stated another way, in embodiments wherein the light control film 300 defines a Fresnel lens, a first subset 20-1 of the first facets 20 may be defined by first angles θ1, while a second subset 20-2 of the first facets 20 may be defined by first angles θ1’ which are substantially opposite to the corresponding first angles θ1 of the first subset 20-1 of first facets 20. That is, as shown in the embodiment of FIG.1A, showing an example of a Fresnel lens, the first facets 20 of first subset 20-1 have first angles in one direction, and the first facets 20 of second subset 20-2 have first angles in substantially equal but opposite directions (compared to their corresponding first angles in subset 20- 1). FIG.1A and the corresponding description are intended as examples only and are not meant to be limiting in any way. Light control film 300 may be a Fresnel lens, a light turning film, or any other appropriate type of light control layer. In some embodiments, at least 80%, or at least 85% or at least 90%, or at least 95% of each of the first 20 and second facets 30 may be coated with a light transmissive layer 40. In some embodiments, light transmissive layer 40 may have an average thickness h of greater than about 0.005 microns, or greater than about 0.01 microns, or greater than about 0.02 microns, or greater than about 0.03 microns, or greater than about 0.04 microns, or greater than about 0.05 microns, or greater than about 0.08 microns, or greater than about 0.1 microns, or greater than about 0.15 microns, or greater than about 0.2 microns. In some embodiments, the light transmissive layer has an average thickness of less than about 0.500 microns. In some embodiments, the light transmissive layer has an average thickness in a range of between 0.005 microns and 0.500 microns, or from 0.01 microns to 0.400 microns, or from about 0.03 microns to about 0.300 microns. In some embodiments, the light transmissive layer has an average thickness in a range of between 0.005 microns and 0.500 microns, or from 0.01 microns to 0.400 microns, or from about 0.03 microns to about 0.300 microns. In some embodiments, light transmissive layer 40 may include a plurality of first inorganic particles 41 (FIG.1B) at a weight loading of greater than about 15%, or greater than about 20%, or greater than about 25%, or greater than about 30%, or greater than about 40%, or greater than about 50%, or greater than about 60%, or greater than about 70%, or greater than about 80%, or greater than about 90%, or greater than about 95%, or greater than about 96%, or greater than about 97%, or greater than about 98%, or greater than about 99%. In some embodiments, the first inorganic particles 41 of the light transmissive layer 40 may be dispersed in a polymeric binder 42 at the weight loading of greater than about 15%. In some embodiments the first inorganic particles 41 are included at a weight loading of from about 15% to 99%, or from 20% to 80%, or from 25% to 70%. In some embodiments, the light transmissive layer has a plurality of first inorganic particles at a volume loading of from about 5% to 95%, or from about 5% to 80%, or from 5% to 70%, or from 10% to 70%. In some embodiments, at least 70%, or at least 75%, or at least 80%, or at least 85%, or at least 90%, or at least 95% of light transmissive layer 40 on each of the second facets 30, 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 light transmissive layer 40 on each of the first facets 20 may be coated with a cover layer 50. In some embodiments, the light transmissive layer 40 coated on the first 20 and second 30 facets may have respective arithmetic average surface roughnesses Ra1 and Ra2, such that Ra1 > Ra2 (see FIG.2B, which is an SEM micrograph showing an example embodiment according to the present description for additional detail). In some embodiments, the first inorganic particles 41 may include one or more of silicon dioxide, titanium dioxide, zirconium dioxide, aluminum oxide, and clay platelets (e.g., the clay platelets may include silicates, including one or more of aluminum silicates and magnesium silicates). In some embodiments, one of the polymeric binder 42 and the plurality of first inorganic particles 41 may include a plurality of positively charged ionic groups, and the other one of the polymeric binder 42 and the plurality of first inorganic particles 41 may include a plurality of negatively charged ionic groups. Ionic groups can be inherently present on the surface of the inorganic particles; below the isoelectric point of the inorganic particle, the surface would possess a plurality of positively charged functional groups (i.e., net positive charge), while, above the isoelectric point, the surface would possess a plurality of negatively charged functional groups (i.e., net negative charge). Alternatively, inorganic particles can be surface-functionalized or surface-modified to impart charged functional groups. Surface functionalization / modification can be done with inorganic and / or organic materials. An example material with inorganic surface modification is colloidal silica with an alumina surface, such as Nalco 1056 (available from Nalco Water, Naperville, IL). As another example, silicon dioxide particles can be surface functionalized with an amino silane to impart positively charged amine groups to the surface. In some embodiments, the polymeric binder 42 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(vinylphosphonic acid), polyurethane, and acrylic. In some embodiments, the light transmission layer 40 may contain a binder at a low weight loading. For example, any binder in the light transmission layer 40 may be at a weight loading of not greater than about 20%, or not greater than about 15%, or not greater than about 10%, or not greater than about 5%, not greater than about or 4%, or not greater than about 3%, or not greater than about 2%, or not greater than about 1%. In some embodiments, light transmission layer 40 may not include any binder. In some embodiments, light transmissive layer 40 may further include a plurality of second inorganic particles 43 (FIG.1C). In some such embodiments, the second inorganic particles 43 may include one or more of silicon dioxide, titanium dioxide, zirconium dioxide, aluminum oxide, and clay platelets (e.g., the clay platelets may include silicates, including one or more of aluminum silicates and magnesium silicates). In some embodiments, one of the plurality of first inorganic particles 41 and the plurality of second inorganic particles 43 may include a plurality of positively charged ionic groups, and the other one of the plurality of first inorganic particles 41 and the plurality of second inorganic particles 43 may include a plurality of negatively charged ionic groups. In some embodiments, light control film 300 may further include a planarizing overcoat 90 covering, and substantially planarizing, structured first major surface 11. FIGS.2A-2B provide additional details for a light control film, such as the light control film 300 of FIG.1A. The following discussion addresses FIGS.1A-1C and 2A-2B as a whole and the figures should be reviewed in conjunction. Looking at FIG.2A, light control film 300 includes a light transmissive body 10 having a structured first major surface 11 opposite a second major surface 12 and including a plurality of first facets 20 and a plurality of second facets 30. In some embodiments, a cover layer 50 may substantially cover at least the second facets 30. In some embodiments, cover layer 50 may be light absorbing. In some such embodiments, the light absorbing cover layer 50 may include a plurality of light absorbing particles. In some such embodiments, the light absorbing particles comprise one or more of a dye, a pigment, and a carbon black. In some embodiments, the light absorbing cover layer 50 may have an optical density 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 1.5, 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. In some embodiments, the optical density is less than about 3.0, or less than about 2.5, or less than about 2.0. In some embodiments the optical density is between 0.5 and 2.5, or between 1.0 and 2.0 or between 1.2 and 1.8. In some embodiments, cover layer 50 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. In some embodiments, the cover layer may have an average thickness of from about 0.05 microns to 1.5 microns, or from about 0.10 microns to 1.0 microns, or from about 0.20 microns to 0.50 microns. In some embodiments of the light control film 300, at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% of the first facets 20 may be curved. In some embodiments, at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 95% of the second facets 30 may be substantially planar. In some embodiments, at least some of the first facets 20 may be substantially planar. In some such embodiments, substantially all first facets 20 may be substantially planar. For light control film 300, and for each of at least two of the second facets 30 (e.g., 30a, 30b), the light absorbing cover layer 50, 50a, 50b may be coated on the second facet 30, 30a, 30b extending along a thickness direction (e.g., the z-axis shown in FIG.2A) of light control film 300. FIG.3 presents contrasting top and side profile views for an embodiment of a light control film. Along the bottom half of FIG.3 is a side view of light control film 300 with first 20 and second 30 facets projecting into the thickness direction of light control film 300 (i.e., the z-direction or z-axis of the coordinate system shown in FIG.3, bottom). The top half of FIG.3 provides a top-down view of light control film 300, aligned with the side view in the bottom half of the figure. In the embodiment of FIG.3, first 20 and second 30 facets are linear facets extending along a length direction (e.g., the y-axis of the coordinate system shown in FIG.3, top) of the light control film and arranged along an orthogonal width direction (e.g., the x-axis in FIG.3, top) of the light control film 300. The side view of light control film 300 is provided again in FIG.4, which illustrates light transmission paths for an embodiment of a light control film. In the embodiment of FIG.4, at least some of first facets 20 are curved. In some embodiments, at least some of the first facets 20 may be substantially planar. In some such embodiments, substantially all first facets 20 may be substantially planar. FIGS.5A-5B show representations of embodiments of the light transmissive and cover layers of a light control film, such as light control film 300 of FIG.1A. FIGS.5A-5B are schematic drawings and not intended to be accurate to scale or proportion. Each of FIGS.5A and 5B may represent an embodiment of one of the light transmissive layer 40 (shown here as 40’) or cover layer 50 (shown here as 50’). In some embodiments, at least one of the light transmissive layer 40’ and cover layer 50’ may be porous comprising a plurality of pores 40’a, 50’a. In some such embodiments, a volume fraction of the pores may be greater than 0.2, or greater than 0.3, or greater than 0.4, or greater than 0.5, or greater than 0.6, or greater than 0.7. In some embodiments, an average size of pores 40’a, 50’a may be less than about 50 nm, or less than about 40 nm, or less than about 30 nm, or less than about 20 nm, or less than about 10 nm, or less than about 5 nm, or less than about 1 nm. FIG.5B shows a representation of an embodiment of either a light transmissive layer 40” or a cover layer 50” (shown in both a top view and a side cutaway view) which is physically discontinuous and which includes a plurality of spaced apart islands 40”a, 50”a separated by gaps 41”a, 51”a. FIGS.6A-6E illustrate display systems including a light control film, such as light control film 300 of FIG.1A. Like-numbered elements in FIGS.6A through 6E shall be assumed to have the same function unless specifically stated otherwise herein, and therefore descriptions of these shared elements may not be repeated. Looking at FIG.6A, in some embodiments, display system 400 may include a light control film 300 disposed on a display 70, the display 70 configured to form an image 71, and a second light control film 60 disposed between light control film 300 and display 70. In some embodiments, second light control film 60 may include a plurality of alternating substantially light transmissive regions 61 and light absorbing regions 62 (e.g., a louver film such as a microlouver as shown in US9,063,284 or a nanolouver as shown in US11,550,183). In some embodiments, a first bonding layer 72 may bond light control film 300 to second light control film 60. In some embodiments, a second bonding layer 74 may bond second light control film 60 to display 70. Looking at FIG.6B, in some embodiments, display system 401 may include a light control film assembly 305 disposed above a display 70, the display 70 configured to form an image 71, wherein there is an air gap 76 between second light control film 60 of light control film assembly 305 and display 70. FIG.6C shows a similar embodiment to FIG.6B, where the light control film assembly 305 includes planarizing overcoat layer 90, wherein there is an air gap 76 between second light control film 60 of light control film assembly 305 and display 70. FIG.6D shows yet another embodiment, wherein the planarizing overcoat layer 90 of light control film assembly 305 shown in FIG 6C is bonded to a transparent lens member 97 with an adhesive 95. In some embodiments, adhesive 95 may have a thickness in the range of from about 10 microns to about 400 microns, or from about 10 microns to about 300 microns, or from about 10 microns to about 150 microns, or from about 25 microns to about 125 microns, or from about 50 microns to about 100 microns. In some embodiments, adhesive layer 95 may have a haze level from about 0.1% to about 70%, or from about 0.1% to about 60%, or from about 0.1% to about 55%, or from about 0.1% to about 50%, or from about 0.1% to about 40%, or from about 2% to about 30%, or from about 5% to about 20%. In some embodiments, adhesive layer 95 may be an optically clear adhesive. In some embodiments, adhesive layer 95 may include laminating adhesives which have properties of pressure sensitive adhesives. In some embodiments, adhesive layer 95 may be a liquid applied adhesive, applied by any suitable method, which is cured to a polymeric state after bonding of transparent lens element 97 and light control assembly 305. In some embodiments, a laminating adhesive may have additional reactive functionality which can be reacted in a secondary curing process In some embodiments, the display systems 400, 401, 402, and 403 may be a curved display system 407 such as that represented in FIG.6E. Curved display system 407 may be curved along at least one direction (e.g., curved along the x-axis of FIG.6B). Similarly, in some embodiments, the light control film 300 and light control film assemblies 305 may be a curved light control film 307, also represented by the schematic drawing of FIG.6E. In such embodiments, the curved light control film 307 may be curved along at least one direction (e.g., the x-axis). FIG.7 illustrates an embodiment of a method of making a light control film, according to the present description. The method includes the steps of: (A) providing a substantially light transmissive body 10 having a structured first major surface 11 and an opposing second major surface 12, the structured first major surface 11 having a plurality of alternating first 20 and second 30 facets, each of the first facets 20 making an average first angle of less than about 90 degrees, or less than about 85 degrees, or less than about 80 degrees, or less than about 75 degrees, or less than about 70 degrees, or less than about 65 degrees, or less than about 60 degrees, or less than about 55 degrees, or less than about 50 degrees, or less than about 45 degrees, or less than about 40 degrees, or less than about 35 degrees, or less than about 30 degrees, or less than about 25 degrees, or less than about 20 degrees, or less than about 15 degrees, or less than about 10 degrees, or less than about 5 degrees with the second major surface 12, each of the second facets 30 making an average second angle of greater than about 60, or greater than about 65 degrees, or greater than about 70 degrees, or greater than about 75 degrees, or greater than about 80 degrees, or greater than about 85 degrees, or greater than about 90 degrees, or greater than about 95 degrees, or greater than about 96 degrees, or greater than about 97 degrees, or greater than about 98 degrees, or greater than about 99 degrees with the second major surface 12; (B) coating the structured first major surface 11 with a light transmissive layer 40 to reduce an etch rate of the material of the first and second facets (e.g., the light transmissive body 10) by at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80% when using a same directional first etching process (e.g., reactive ion etching, laser etching, etc.), the light transmissive layer covering at least 80%, or at least 85% or at least 90%, or at least 95% of each of the first 20 and second 30 facets and including a plurality of first inorganic particles (e.g., see particles 41, FIG.1B) at a weight loading of greater than about 15%, or greater than about 20%, or greater than about 25%, or greater than about 30%, or greater than about 40%, or greater than about 50%, or greater than about 60%, or greater than about 70%, or greater than about 80%, or greater than about 90%, or greater than about 95%, or greater than about 96%, or greater than about 97%, or greater than about 98%, or greater than about 99%; (C) coating light transmissive layer 40 with a cover layer 50 so that at least 80%, or at least 85% or at least 90%, or at least 95% of light transmissive layer 40 is covered by cover layer 50; and (D) etching cover layer 50 using the directional first etching process to remove more than about 80%, or more than about 85%, or more than about 90%, or more than about 95%, or more than about 98%, or more than about 99% of cover layer 50 from each first facet 20 but remove less than about 40%, or less than about 35%, or 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 cover layer 50 from each second facet 30, resulting in the light transmissive layer 40 coated on the first 20 and second 30 facets having respective arithmetic average surface roughnesses Ra1 and Ra2, such that Ra1 > Ra2. Finally, FIG.8 includes a TEM micrograph of an embodiment of a light control film having a first light transmissive layer 40 and a second light transmissive layer 45, according to the present description. The microscope image of FIG.8 shows a close-up view of an area of light control film 300 shown in the dashed rectangle region in the bottom half of the figure. In some embodiments, light control film 300 may include a light transmissive body 10, a first light transmissive layer 40, a light absorbing layer 50, a planarizing overcoat 90, and a second light transmissive layer 45. In some embodiments, light transmissive body 10 may have a plurality of alternating linear first 20 and second 30 facets extending along a first direction (e.g., the y-axis shown in FIG.3A) and arranged along a different second direction (e.g., the x-axis of FIG.3A). In some embodiments, first light transmissive layer 40 may have a first average thickness of greater than about 0.005 microns, or greater than about 0.01 microns, or greater than about 0.02 microns, or greater than about 0.03 microns, or greater than about 0.04 microns, or greater than about 0.05 microns, or greater than about microns, 0.08 microns, or greater than about 0.1 microns, or greater than about 0.15 microns, or greater than about 0.2 microns and coated on at least 80%, or at least 85%, or at least 90%, or at least 95% of each of the first 20 and second 30 facets. In some embodiments, the light transmissive layer 40 may include a plurality of first inorganic particles (e.g., particles 41 of FIG.1B) including a first inorganic material (e.g., Si). In some embodiments, light absorbing layer 50 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 and coated on 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 light transmissive layer 40 on each of the second facets 30 and on 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 light transmissive layer 40 on each of the first facets 20. In some embodiments, planarizing overcoat 90 covers light absorbing layer 50 and substantially planarizes structured first major surface 11. In some embodiments, for each of at least some of the first 20 and second 30 facets, a second light transmissive layer 45 (shown in electron micrograph) may be disposed between planarizing overcoat 90 and light absorbing layer 50 that covers the facet. In some embodiments, second light transmissive layer 45 may include the first inorganic material and may have a second average thickness that is less than about 20 nm, or less than about 10 nm, or less than about 5 nm. In some embodiments, the second light transmissive layer 45 may be discontinuous. Examples Unless otherwise noted, all parts, percentages, ratios, etc. in the Examples and the rest of the specification are by weight. Materials Used in the Examples Abbreviation Description PU2560 Aliphatic urethane difunctional acrylate oligomer from Miwon Specialty Chemical, South Korea M210 Hydroxy pivalic acid neopentyl glycol diacrylate [HPNDA] from Miwon Specialty Chemical Omnirad 4265 Photoinitiator - blend of 2, 4, 6-trimethylbenzoyl-diphenyl-phosphine oxide (50%) and 2-hydroxy-2-methyl-1-phenylpropanone (50%), obtained under the trade designation “OMNIRAD 4265” from IGM Resins USA, Inc., Charlotte, NC O2Oxygen gas (UHP compressed) obtained from Oxygen Service Company, St. Paul, MN SC72 Cationic polyurethane dispersion, obtained under the trade designation “SANCURE 20072” from Lubrizol Corp., Wickliffe, OH SiO2-20nm Anionic silicon dioxide nanoparticles with average particle size of 20 nm and sodium stabilized, obtained under the trade designation “NALCO 1050” from Nalco Water, Naperville, IL. EXPCB Anionic, surface-modified carbon black dispersion obtained from Cabot Corp., Boston, MA NaCl Sodium chloride, obtained as a 25% solids solution in water from Univar Solutions, Houston, TX NaOH Sodium hydroxide, obtained as a 1M solution in water from Avantor Performance Materials, Radnor, PA PL92 Non-ionic surfactant, obtained under the trade designation, “PLURONIC L-92” from BASF Corp., Florham Park, NJ Resin A Formulation similar to those in US 9,360,591.   Method for Cast-and-Cure Microreplication to Make Fresnel Lens Film A diamond was used to cut a tool having a co-planar, microscale Fresnel lens structure. Resin B was prepared by mixing the materials in Table 1 below. Table 1: Composition of Resin B Used to Make Microstructured Film Material Parts by Weight PU2560 49.50 M210 49.50 Omnirad 4265 1.00 A “cast-and-cure” microreplication process was carried out with Resin B and the tool described above on a continuous cast and cure microreplication line. Resin B was heated to 100°F and coated onto a PET film with microlouvers (e.g., similar to that described in US9,063,284) on the opposite side. The louvers were protected by a PP premask. The die temperature at coating was 100°F. After coating, the coated film passed under IR heaters at 130°F. The coated film then passed between a rubber nip roll and Fresnel lens tool at a nip pressure of 18 psi and tool temp of 130°F. The resulting film was cured using three sequential banks of Fusion D lamps at 100%, 60%, and 60% power, respectively. The cured refractive index of Resin B was 1.484 measured at 532nm. Refractive index is measured using a Metricon Prism Coupler Model 2010 / M. Method to Coat an Inorganic Etch Stop (Comparative) A silicon containing etch resist was deposited using a home-built parallel plate capacitively coupled plasma reactor as described in U.S. Patent Nos.6,696,157 (David et al.). The chamber has a central cylindrical powered electrode with a surface area of 18.3 ft2. After placing the Fresnel lens film on the powered electrode, the reactor chamber was pumped down to a base pressure of less than 1.3 Pa (2 mTorr). O2and HMDSO gasses were flowed into the chamber at rates of 1500 SCCM and 300 SCCM, respectively. Treatment was carried out using a plasma enhanced CVD method by coupling RF power into the reactor at a frequency of 13.56 MHz and an applied power of 7500 Watts. The film was moved through the reaction zone at a rate of 20 feet per minute, resulting in an approximate treatment time of 15 seconds. After completing the deposition, RF power was turned off and the chamber was returned to atmospheric pressure. Method to Coat a Layer-by-Layer Etch Stop (“Light Transmissive Layer”) A nano-SiO2-containing etch stop was deposited conformally on the Fresnel lens film via layer-by-layer (LbL) deposition on a coater as described in US Pat. No.10,926,289 (Kawakami et al.). Two separate coating solutions were prepared: Cation and Etch Stop Anion. The Cation solution was 2.5% solids SC72 with 200 mM NaCl and 0.1% PL92 in de-ionized (DI) water. The Etch Stop Anion solution was 1.0% solids nano-SiO2(20 nm particle size), 125 mM NaCl, and 0.1% PL92 in DI water, with pH adjusted to about 10 using 1M NaOH. The etch stop comprised six bilayers, denoted as (SC72 / SiO2)6. The Cation and Etch Stop Layer Anion solutions were separately coated onto the microstructured film with a #4 Mayer Rod fed with needles from a liquid delivery manifold at a flow rate of about 200 mL / min at each coating station. Excess coating solution was removed from the web after each deposition step with air-knives gapped at 40 mil to the web with pressure of about 35 psi. Line speed was 50 feet per minute. Thickness of the LbL etch stop coating, determined by analyzing an SEM image (acquired toward the edge of the lens) with ImageJ software, was 173 ± 34 nm. Weight percent of SiO2, determined by the “Method for Determining Weight% of Inorganic Particles in LbL Etch Stop Coatings” from an equivalent etch stop coating deposited with a small-scale spray coater, was 51.0 wt%. Porosity of this etch stop was not directly measured, but generally the SC72 polymer provides relatively non-porous coatings due to its film forming nature. Calculation of approximate vol% of inorganic particles, assuming 0% porosity, using a density of 2.05 g / cm3for the SiO2and a density of 1.00 g / cm3for the SC72 polymer, gives 34 vol% inorganic particles. Method to Coat a Light Absorbing Cover Layer A black, light-absorbing cover layer was coated conformally on the Fresnel lens film via layer-by-layer (LbL) deposition on a coater as described in US Pat. No.10,926,289 (Kawakami et al.). Two separate coating solutions were prepared: Cation and Cover Layer Anion. The Cation solution was 2.5% solids SC72 with 200 mM NaCl and 0.1% PL92 in DI water. The Cover Layer Anion solution was 2.5% solids EXPCB with 50 mM NaCl and 0.1% PL92 in DI water. The light- absorbing coating construction comprised six bilayers, denoted as (SC72 / EXPCB).Microstructured film was threaded through the coating line. The Cation and Cover Layer Anion solutions were separately coated onto the microstructured film with a #4 Mayer Rod fed with needles from a liquid delivery manifold at a flow rate of about 200 mL / min at each coating station. Excess coating solution was removed from the web after each deposition step with air-knives gapped at 40 mil to the web with pressure of about 35 psi. Line speed was 50 feet per minute. Thickness of the LbL coating, determined by analyzing an SEM image (acquired toward the edge of the lens) with ImageJ software, was 337 ± 17 nm. Method to Selectively Remove Portions of the Light Absorbing Cover Layer Reactive ion etching was carried out in the same home-built reactor chamber used in the “Method to Coat an Inorganic Etch Stop (Comparative)”. After placing the coated film on the powered electrode, the reactor chamber was pumped down to a base pressure of less than 1.3 Pa (1 mTorr). O2gas was flowed into the chamber at a rate of 1000 SCCM. 13.56 MHz RF power was subsequently coupled into the reactor with an applied power of 9000 W. The film was then carried through the reaction zone at a rate of 1.5 ft / min, to achieve an exposure time of approximately 200 sec. At the end of this treatment time, the RF power and the gas supply were stopped, and the chamber was returned to atmospheric pressure. Method to Backfill Resin A at 100°F was coated on the primed side of 2-mil PET with PP premask laminated to the backside of the PET at 30 fpm. The coating die temperature was also 100°F. Prior to lamination, the film passed under IR heaters at 120°F.  The structured film was brought in from a separate unwind and laminated to the coated PET film in a steel-rubber nip. The steel roll was heated to 140°F, rubber roll was unheated. While held against the steel roll, the laminate was then UV cured using two banks of Fusion D bulbs, each at 60% power. A takeaway nip was used to remove the cured laminate from the steel roll. The refractive index of the planarizing layer was 1.681 measured at 532nm. Measured with Metricon 2010 / M Method for Measuring Peel Strength When a planarizing layer 90 is disposed between the structured first major surface 11 of light control film 300 and substrate 99 (e.g., a sheet of primed PET film) as shown in Fig.9, the adhesion between the light control film 300 and planarization layer 90 can be tested using a 90-degree peel test such as that described in ASTM D6862-11(2021) with some modifications. A strip of dimension 25 mm x 800 mm of the film 450 can be cut in a direction parallel with the linear prism direction. The substrate 99 can be attached to a rigid plate with 3M 665 double sided tape. The louver side of the film is scored to initiate the peel at the interface between the first major surface 11 of light control film 300 and planarizing layer 90 at location 98. 3M 396 tape is adhered to surface 77 and aligned with the substrate and rigid plate. The testing machine used was an Imass 2100 (IMASS, Inc., Strongsville, OH). An inch section of the louver side is placed into the test machine jaws or clamps. The test is run with a 10 lb load cell and a constant crosshead speed of 10 in / min for a 5- second average of data collection. Method for Measuring %Haze %Haze was measured using a BYK (Geretsried, Germany) Haze-Gard Plus instrument. Method for Acquiring Scanning Electron Microscopy (SEM) Images Samples were freeze fractured with liquid nitrogen. Imaging was done with a Hitachi S4700 Field Emission microscope. Images in this document are taken from the center of the Fresnel lens after delaminating the backfill resin (see, e.g., FIG.2B). Method for Acquiring Transmission Electron Microscopy (TEM) Images Samples for TEM analysis were room-temperature ultra-microtomed. Cut thickness ranged between 100 and 130 nm. Microtomy-cut direction was chosen to be parallel or nearly parallel to a majority of the interfaces. TEM analysis was performed on a FEI-Osiris TEM, operating at 200 kV. The STEM imaging mode was used. Bright Field (BF), Dark Field (DF), and High Angle Annular Dark Field (HAADF) images were acquired. X-ray microanalysis was performed using a Bruker Super-X quad x-ray SDD (silicon drift detector) and accompanying Espirit quantitative analysis software system (see, e.g., FIG.8). Method for Determining Weight% of Inorganic Particles in LbL Etch Stop Coatings A layer-by-layer (LbL) spray coater, purchased from Svaya Nanotechnologies (Sunnyvale, CA) and modeled after the system described in US 8,234,998 (Krogman et al.) as well as Krogman et al. Automated Process for Improved Uniformity and Versatility of Layer-by-Layer Deposition, Langmuir 2007, 23, 3137-3141, was used to deposit LbL etch stop coatings on a 12”x12” glass plate. The coatings were scraped off the plate with a razor blade. The powder samples were analyzed using a TA Instruments Discovery Thermogravimetric Analyzer (TGA) in HiRes mode. The sample was subjected to a heating profile ranging from room temperature (~ 30 °C) to 700 °C in a nitrogen atmosphere, with a heating rate of 20.0 °C / min and a resolution setting of 4.0. Under these conditions, the instrument heats the sample until weight loss is detected, at which point the temperature stabilizes until weight loss diminishes, and then heating recommences. At 700°C the atmosphere was then switched to air and the HiRes heating ramp was continued to 800° C. The weight% residue at 800° C was taken as the weight % of inorganic particles (e.g., metal oxide) in the coating samples.

[0002] CE1 No Etch Stop Step 1: A microstructured film was prepared as described in “Method for Cast-and-Cure Microreplication to Make Fresnel Lens Film.” Step 2: The microstructured film was coated with a light absorbing LbL coating as described in “Method to Coat a Light Absorbing Cover Layer.” Step 3: The light absorbing layer was etched as described in “Method to Selectively Remove the Light Absorbing Cover Layer.” Step 4: The structured film of Step 3 was backfilled as described in “Method to Backfill.” Peel values and haze measurements are recorded in Table 2. CE2 Planar Etch Stop Step 1: A microstructured film was prepared as described in “Method for Cast-and-Cure Microreplication to Make Fresnel Lens Film.” Step 2: An inorganic etch stop was applied the microstructured film as described in “Method to Coat an Inorganic Etch Stop (Comparative).” Step 3: The microstructured film was coated with a light absorbing LbL layer as described in “Method to Coat a Light Absorbing Cover Layer.” Step 4: The light absorbing layer was etched as described in “Method to Selectively Remove the Light Absorbing Cover Layer.” Step 5: The structured film of Step 4 was backfilled as described in “Method to Backfill.” Peel values and haze measurements are recorded in Table 2. EX 1 LbL Etch Stop Step 1: A microstructured film was prepared as described in “Method for Cast-and-Cure Microreplication to Make Fresnel Lens Film.” Step 2: A layer-by-layer etch stop was applied on the microstructured film as described in “Method to Coat a Layer-by-Layer Etch Stop (Light Transmissive Layer).” Step 3: The microstructured film was coated with a light absorbing LbL coating as described in “Method to Coat a Light Absorbing Cover Layer.” Step 4: The light absorbing layer was etched as described in “Method to Selectively Remove the Light Absorbing Cover Layer.” Step 5: The structured film of Step 4 was backfilled as described in “Method to Backfill.” Peel values and haze measurements are recorded in Table 2. Example 1 (EX1) shows comparable haze to comparative example 2 (CE2) while demonstrating improved adhesion. Table 2. Example Peel and Haze Values 90° DW Peel, Patent grams / inch Haze (Center of Example ID width RMS Lens) CE 1 999 0 36.5% CE 2 2 1 13.6% EX1 107 4 16.6% Terms such as “about” will be understood in the context in which they are used and described in the present description by one of ordinary skill in the art. If the use of “about” as applied to quantities expressing feature sizes, amounts, and physical properties is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, “about” will be understood to mean within 10 percent of the specified value. A quantity given as about a specified value can be precisely the specified value. For example, if it is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, a quantity having a value of about 1, means that the quantity has a value between 0.9 and 1.1, and that the value could be 1. Terms such as “substantially” will be understood in the context in which they are used and described in the present description by one of ordinary skill in the art. If the use of “substantially equal” is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, “substantially equal” will mean about equal where about is as described above. If the use of “substantially parallel” is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, “substantially parallel” will mean within 30 degrees of parallel. Directions or surfaces described as substantially parallel to one another may, in some embodiments, be within 20 degrees, or within 10 degrees of parallel, or may be parallel or nominally parallel. If the use of “substantially aligned” is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, “substantially aligned” will mean aligned to within 20% of a width of the objects being aligned. Objects described as substantially aligned may, in some embodiments, be aligned to within 10% or to within 5% of a width of the objects being aligned. All references, patents, and patent applications referenced in the foregoing are hereby incorporated herein by reference in their entirety in a consistent manner. In the event of inconsistencies or contradictions between portions of the incorporated references and this application, the information in the preceding description shall control. Descriptions for elements in figures should be understood to apply equally to corresponding elements in other figures, unless indicated otherwise. Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and / or equivalent implementations can be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this disclosure be limited only by the claims and the equivalents thereof.

Claims

What is claimed:

1. A light control film comprising a structured first major surface opposite a second major surface, the structured first major surface comprising a plurality of alternating first and second facets, each of the first facets making an average first angle of less than about 90 degrees with the second major surface, each of the second facets making an average second angle of greater than about 60 degrees with the second major surface, at least 80% of each of the first and second facets coated with a light transmissive layer having an average thickness of greater than about 0.005 microns and comprising a plurality of first inorganic particles at a volume loading of greater than about 5%, at least 70% of the light transmissive layer on each of the second facets and at most 30% of the light transmissive layer on each of the first facets coated with a cover layer, the light transmissive layer coated on the first and second facets having respective arithmetic average surface roughnesses Ra1 and Ra2, Ra1 > Ra2.

2. The light control film of claim 1, wherein each first facet makes a first angle with the second major surface, and wherein a first angle of at least one of the first facets varies with a first angle of at least one other of the first facets.

3. The light control film of claim 2, wherein each second facet makes a second angle with the second major surface, and wherein each of the second angles of each second facet are substantially equal.

4. The light control film of claim 3, wherein the first angles of a first subset of first facets are substantially opposite to the first angles of a second subset of first facets.

5. The light control film of claim 4, wherein the light control film defines a Fresnel lens.

6. The light control film of claim 1, wherein the light control film is a light turning film.

7. The light control film of claim 1, wherein the first inorganic particles comprise one or more of silicon dioxide, titanium dioxide, zirconium dioxide, aluminum oxide, and clay platelets.

8. The light control film of claim 7, wherein the clay platelets comprise silicates.

10. The light control film of claim 8, wherein the silicates comprise one or more of aluminum silicates and magnesium silicates.

11. The light control film of claim 1, wherein the cover layer is light absorbing.

12. The light control film of claim 1, wherein the cover layer has an average thickness of greater than about 0.05 microns.

13. The light control film of claim 1, wherein at least 50% of the first facets are substantially curved.

14. A display system comprising the light control film of claim 1 disposed on a display configured to form an image, and a second light control film disposed between the light control film and the display, the second light control film comprising a plurality of alternating substantially light transmissive and light absorbing regions.

15. The light control film of claim 1, further comprising a planarizing overcoat conformally covering, and substantially planarizing, the structured first major surface.

16. The light control film of claim 15, wherein a refractive index of the planarizing overcoat may be different from a refractive index of the first and second facets by greater than about 0.

07.

17. A light control film comprising: a light transmissive body comprising a plurality of alternating linear first and second facets; a light transmissive layer having an average thickness of greater than about 0.005 microns and coated on at least 80% of each of the first and second facets, the light transmissive layer comprising a plurality of first inorganic particles at a volume loading of greater than about 5%; and a light absorbing layer having an average thickness of greater than about 0.05 microns and coated on at least 70% of the light transmissive layer on each of the second facets and on at most 30% of the light transmissive layer on each of the first facets; such that for each of at least a majority of the second facets, the light absorbing layer coated on the second facet extends along a thickness direction of the light control film to within at least the average thickness of the light transmissive layer from the first facet adjacent to the second facet.

18. A light control film comprising: a light transmissive body comprising a plurality of alternating linear first and second facets extending along a first direction and arranged along a different second direction;a first light transmissive layer having a first average thickness of greater than about 0.005 microns and coated on at least 80% of each of the first and second facets, the light transmissive layer comprising a plurality of first inorganic particles comprising a first inorganic material; a light absorbing layer having an average thickness of greater than about 0.05 microns and coated on at least 70% of the light transmissive layer on each of the second facets and on at most 30% of the light transmissive layer on each of the first facets; and a planarizing overcoat conformally covering the light absorbing layer and substantially planarizing the structured first major surface, wherein for each of at least some of the first and second facets, a second light transmissive layer is disposed between the planarizing overcoat and the light absorbing layer that cover the facet, the second light transmissive layer comprising the first inorganic material and having a second average thickness that is less than about 20 nm.

19. The light control film of claim 18, wherein the second light transmissive layer is discontinuous.

20. The light control film of claim 18, wherein 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

Images