Liquid crystal dimmable film

Abstract

In one example, a crystal cell comprises: a first substrate, a second substrate, first spacers and second spacers sandwiched between the first substrate and the second substrate to define a gap between the first substrate and the second substrate, the first spacers being fixedly bonded to each of the first substrate and the second substrate, the second spacers being movable between the first and second substrates, a sealant sandwiched between the first substrate and the second substrate and enclosing the first spacers and the second spacers, and a liquid crystal enclosed by the sealant, the first substrate, and the second substrate. Examples of a dimmable glass incorporating liquid crystal cells and methods of manufacturing the liquid crystal cells are also provided.

1 . An apparatus comprising:
 a first substrate;   a second substrate;   first spacers and second spacers sandwiched between the first substrate and the second substrate to define a gap between the first substrate and the second substrate, the first spacers being fixedly bonded to each of the first substrate and the second substrate, the second spacers being movable between the first and second substrates;   a sealant sandwiched between the first substrate and the second substrate and enclosing the first spacers and the second spacers; and   a liquid crystal enclosed by the sealant, the first substrate, and the second substrate.   
     
     
         2 . The apparatus of  claim 1 , wherein the first spacers and the second spacers include at least one of silica gel balls or plastic balls. 
     
     
         3 . The apparatus of  claim 2 , wherein the first spacers include resin to provide the fixed bonding between the at least one of silica gel balls or plastic balls with each of the first substrate and the second substrate. 
     
     
         4 . The apparatus of  claim 3 , wherein the resin comprises at least one of: an epoxy resin or an acrylic resin. 
     
     
         5 . The apparatus of  claim 3 , wherein the first spacers are formed by printing a mixture of the silica gel balls and the resin on the first substrate via at least one of a screen or a stencil. 
     
     
         6 . The apparatus of  claim 3 , wherein the second spacers include an adhesive to provide bonding between the silica gel balls with each of the first substrate and the second substrate. 
     
     
         7 . The apparatus of  claim 1 , wherein each of the first substrate and the second substrate comprises a flexible material. 
     
     
         8 . The apparatus of  claim 7 , wherein the flexible material comprises at least one of: glass, polycarbonate (PC), polyethylene terephthalate (PET), or cellulose triacetate (TAC). 
     
     
         9 . The apparatus of  claim 1 , wherein each of the first substrate and the second substrate is coated with an electrical conductive material to conduct a voltage. 
     
     
         10 . The apparatus of  claim 9 , wherein the electrical conductive material comprises Indium tin oxide (ITO). 
     
     
         11 . The apparatus of  claim 1 , wherein each of the first substrate and the second substrate includes a Polyamide (PI) coating having a rubbing pattern to align molecules of the liquid crystal. 
     
     
         12 . The apparatus of  claim 11 , wherein the PI coating of the first substrate and the PI coating of the second substrate have anti-parallel rubbing directions; and
 wherein the liquid crystal comprises a guest-host (GH) liquid crystal.   
     
     
         13 . The apparatus of  claim 12 , wherein the GH liquid crystal cells comprise dye molecules; and
 wherein a color of the dye molecules is configured to set a color of light transmitted through at least one of the first substrate or the second substrate.   
     
     
         14 . The apparatus of  claim 11 , wherein the PI coating of the first substrate and the PI coating of the second substrate have perpendicular rubbing directions; and
 wherein the liquid crystal comprises a twist-nematic (TN) liquid crystal.   
     
     
         15 . The apparatus of  claim 14 , further comprising a first polarizer film and a second polarizer film sandwiching the liquid crystal. 
     
     
         16 . An apparatus comprising:
 a first glass layer;   a first interlayer;   a liquid crystal cell;   a second interlayer; and   a second glass layer,   wherein:
 the liquid crystal cell is part of a dimmable liquid crystal film having an adjustable light transmittance; 
 the first interlayer is configured to hold fragments of the first glass layer together when the first glass layer is shattered; 
 the second interlayer is configured to hold fragments of the second glass layer together when shattered; and 
 the liquid crystal cell is sandwiched between the first glass layer and the second glass layer and bonded to a first surface of the first glass layer via the first interlayer and bonded to a second surface of the second glass layer via the second interlayer. 
   
     
     
         17 . The apparatus of  claim 16 , wherein the first interlayer and the second interlayer comprise at least one of: polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA), or polyurethane (TPU); and
 wherein the first interlayer and the second interlayer are formed by a curing process, the curing process including applying a pressure exceeding the atmospheric pressure on the liquid crystal cell.   
     
     
         18 . The apparatus of  claim 17 , wherein the first interlayer and the second interlayer are configured as an ultraviolet light blocking layer. 
     
     
         19 . The apparatus of  claim 17 , wherein the liquid crystal cell comprises:
 a first substrate;   a second substrate;   first spacers and second spacers sandwiched between the first substrate and the second substrate to define a gap between the first substrate and the second substrate, the first spacers being fixedly bonded to each of the first substrate and the second substrate, the second spacers being movable between the first and second substrates;   a sealant sandwiched between the first substrate and the second substrate and enclosing the first spacers and the second spacers; and   a liquid crystal enclosed by a sealant, the first substrate, and the second substrate.   
     
     
         20 . The apparatus of  claim 19 , wherein each of the first substrate and the second substrate comprises a flexible material. 
     
     
         21 . The apparatus of  claim 20 , wherein the flexible material comprises at least one of: glass, polycarbonate (PC), polyethylene terephthalate (PET), or cellulose triacetate (TAC). 
     
     
         22 . The apparatus of  claim 21 , wherein at least one of the first substrate or the second substrate is coated with an infra-red light blocking layer. 
     
     
         23 . The apparatus of  claim 20 , wherein each of the first glass layer and the second glass layer has a curved surface; and
 wherein the first substrate and the second substrate are bent to conform with the curved surfaces of the first glass layer and the second glass layer.   
     
     
         24 . The apparatus of  claim 16 , wherein at least one of the first glass layer or the second glass layer is coated with an infra-red blocking layer. 
     
     
         25 . The apparatus of  claim 24 , wherein the infra-red blocking layer is formed on the at least one of the first glass layer or the second glass layer based on at least one of: thermal evaporation, electron beam evaporation, ion assisted deposition (IAD), or ion beam sputtering (IBS). 
     
     
         26 . The apparatus of  claim 21 , further comprising:
 an infra-red film;   a third interlayer; and   a fourth interlayer;   wherein the infra-red film is sandwiched between the first glass layer and the liquid crystal film, or between the liquid crystal film and the second glass layer; and   wherein the infra-red film is bonded to the first glass layer and the liquid crystal film, or to the liquid crystal film and to the second glass layer, via respectively the third interlayer and the fourth interlayer.   
     
     
         27 . The apparatus of  claim 26 , wherein the third interlayer and the fourth interlayer comprise at least one of: polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA), or polyurethane (TPU); and
 wherein the third interlayer and the fourth interlayer are formed by the curing process.   
     
     
         28 . The apparatus of  claim 16 ,
 wherein the apparatus is configured to:
 in a first mode, set the light transmittance of the dimmable liquid crystal film to a first level of light transmittance; and 
 in a second mode, set the light transmittance of the dimmable liquid crystal film to a second level of light transmittance. 
   
     
     
         29 . The apparatus of  claim 16 , wherein the light transmittance of the dimmable liquid crystal film is set based on an ambient light intensity. 
     
     
         30 . The apparatus of  claim 29 , further comprising:
 a light sensor; and   driver circuits,   wherein the light sensor is configured to generate sensor data representing a measurement of the ambient light intensity; and   wherein the driver circuits are configured to generate, based on the sensor data, signals to generate an electric field across the liquid crystal cell to adjust the light transmittance of the dimmable liquid crystal film based on the ambient light intensity.   
     
     
         31 . An apparatus comprising:
 a first glass layer;   a first interlayer;   a second glass layer;   a second interlayer;   a liquid crystal cell;   a third interlayer; and   a third glass layer,   wherein:
 the first glass layer is bonded to the second glass layer via the first interlayer; 
 the liquid crystal cell is sandwiched between second glass layer and the third glass layer and is bonded to the second glass layer via the second interlayer and to the third glass layer via the third interlayer; and 
 the first interlayer is configured to hold fragments of the first glass layer and the second glass layer together when at least one of the first glass layer or the second glass layer is shattered. 
   
     
     
         32 . A method, comprising:
 forming a sealant at first pre-determined locations on at least one of a first substrate or a second substrate to define a base area of a liquid crystal cell;   forming mixtures including resin and first spacers at second pre-determined locations of a first area of the first substrate corresponding to the base area of the liquid crystal cell;   spraying a solution containing second spacers over a second area on the second substrate corresponding to the base area of the liquid crystal cell;   spraying a solution containing first spacers on a first area on the first substrate corresponding to the base area of the liquid crystal cell;   orienting the first substrate and the second substrate to enable the first spacers to join the first substrate via the resin and to enable the second spacers to join the second substrate;   filling liquid crystal into a cell space defined by the sealant, the first substrate, and the second substrate; and   performing a curing process to harden the sealant and to form fixed bonding between the first spacers and each of the first substrate and the second substrate via the resin.   
     
     
         33 . The method of  claim 32 , wherein filling liquid crystal into the cell space comprises:
 dispensing the liquid crystal into the cell space between the first substrate and the second substrate; and   pressing the first substrate and the second substrate against the liquid crystal,   wherein the curing process is performed after the pressing.   
     
     
         34 . The method of  claim 33 , wherein the curing process comprises at least one of: an ultra-violet curing and a thermal curing process. 
     
     
         35 . The method of  claim 33 , further comprising:
 controlling a first pair of rollers to unroll a first roll of substrate comprising the first substrate; and   controlling a second pair of rollers to unroll a second roll of substrate comprising the second substrate,   wherein the pressing of the first substrate and the second substrate against the liquid crystal is performed based on moving the first substrate and the second substrate through a gap between a first roller of the first pair of rollers and a second roller of the second pair of rollers; and   wherein the dispensing of the liquid crystal into the cell pace between the first substrate and the second substrate is performed when at least a part of the first substrate and at least a part of the second substrate are in the gap between the first roller and the second roller.   
     
     
         36 . The method of  claim 35 , wherein the first roller, the gap, and the second roller are aligned along a vertical axis. 
     
     
         37 . The method of  claim 35 , wherein the first roller, the gap, and the second roller are aligned along a horizontal axis. 
     
     
         38 . The method of  claim 33 , wherein the mixtures are printed via at least one of: a stencil, a wire mesh, or a steel mesh. 
     
     
         39 . The method of  claim 33 , further comprising:
 coating the first substrate with an electrical conductive material;   coating the second substrate with an electrical conductive material;   patterning the electrical conductive material on the first substrate to form a first electrode; and   patterning the electrical conductive material on the second substrate to form a second electrode.   
     
     
         40 . The method of  claim 39 , wherein the patterning of the electrical conductive material on the first substrate and the second substrate comprises photolithography followed by etching. 
     
     
         41 . The method of  claim 39 , further comprising:
 forming a first layer of polyamide on the first electrode;   forming a second layer of polyamide on the second electrode; and   rubbing the first layer of polyamide against the second layer of polyamide based on a target orientation of liquid crystal molecules on the first layer of polyamide with respect to liquid crystal molecules on the second layer of polyamide.   
     
     
         42 . The method of  claim 41 , wherein the first layer of polyamide and the second layer of polyamide are formed on, respectively, the first electrode and the second electrode based on a letterpress printing process followed by a thermal curing process. 
     
     
         43 . The apparatus of  claim 28 , wherein the first level of light transmittance corresponds to a maximum level, and the second level of light transmittance corresponds to a minimum level.