Systems and Methods for Manufacturing Waveguide Cells

Abstract

Systems for the manufacturing of waveguide cells in accordance with various embodiments can be configured and implemented in many different ways. In many embodiments, various deposition mechanisms are used to deposit layer(s) of optical recording material onto a transparent substrate. A second transparent substrate can be provided, and the three layers can be laminated to form a waveguide cell. Suitable optical recording material can vary widely depending on the given application. In some embodiments, the optical recording material deposited has a similar composition throughout the layer. In a number of embodiments, the optical recording material spatially varies in composition, allowing for the formation of optical elements with varying characteristics. Regardless of the composition of the optical recording material, any method of placing or depositing the optical recording material onto a substrate can be utilized.

What is claimed is: 
     
         1 . A method for manufacturing waveguide cells, the method comprising;
 providing a first substrate;   determining a predefined grating characteristic; and   depositing a layer of optical recording material onto the first substrate using at least one deposition head, wherein the optical recording material deposited over the grating region is formulated to achieve the predefined grating characteristic.   
     
     
         2 . The method of  claim 1 , further comprising:
 providing a second substrate;   placing the second substrate onto the deposited layer of optical recording material; and   laminating the first substrate, the layer of optical recording material, and the second substrate.   
     
     
         3 . The method of  claim 1 , wherein depositing the layer of optical recording material comprises:
 providing a first mixture of optical recording material;   providing a second mixture of optical recording material; and   depositing the first and second mixtures of optical recording material onto the first substrate in a predetermined pattern using the at least one deposition head.   
     
     
         4 . The method of  claim 3 , wherein:
 the first mixture of optical recording material comprises a first bead; and   the second mixture of optical recording material comprises a second bead that is a different size from the first bead.   
     
     
         5 . The method of  claim 3 , wherein the first mixture of optical recording material has a different percentage by weight of liquid crystals than the second mixture of optical recording material. 
     
     
         6 . The method of  claim 3 , further comprising defining a grating region and a nongrating region on the first substrate, wherein:
 the first mixture of optical recording material comprises a liquid crystal and a monomer;   the second mixture of optical recording material comprises a monomer; and   depositing the first and second mixtures of optical recording material onto the first substrate in the predetermined pattern comprises:
 depositing the first mixture of optical recording material over the grating region; and 
 depositing the second mixture of optical recording material over the nongrating region. 
   
     
     
         7 . The method of  claim 3 , wherein the first mixture of optical recording material is a polymer dispersed liquid crystal mixture comprising:
 a monomer;   a liquid crystal;   a photoinitiator dye; and   a coinitiator.   
     
     
         8 . The method of  claim 7 , wherein the polymer dispersed liquid crystal mixture comprises an additive selected from the group consisting of: a photoinitiator, nano particles, low-functionality monomers, additives for reducing switching voltage, additives for reducing switching time, additives for increasing refractive index modulation, and additives for reducing haze. 
     
     
         9 . The method of  claim 1 , wherein the at least one deposition head comprises at least one inkjet print head. 
     
     
         10 . The method of  claim 8 , wherein depositing the layer of optical recording material comprises:
 providing a first mixture of optical recording material;   providing a second mixture of optical recording material;   printing a first dot of the first mixture of optical recording material using the at least one inkjet print head; and   printing a second dot of the second mixture of optical recording material adjacent to the first dot using the at least one inkjet print head.   
     
     
         11 . The method of  claim 9 , wherein:
 the at least one inkjet print head comprises a first inkjet print head and a second inkjet print head; and   depositing the layer of optical recording material comprises:
 providing a first mixture of optical recording material; 
 providing a second mixture of optical recording material; 
 printing the first mixture of optical recording material onto the first substrate using the first inkjet print head; and 
 printing the second mixture of optical recording material onto the first substrate using the second inkjet print head. 
   
     
     
         12 . The method of  claim 1 , wherein the predefined grating characteristic comprises a characteristic selected from the group consisting of: refractive index modulation, refractive index, birefringence, liquid crystal director alignment, and grating layer thickness. 
     
     
         13 . The method of  claim 1 , wherein the predefined grating characteristic comprises a spatial variation of a characteristic selected from the group consisting of: refractive index modulation, refractive index, birefringence, liquid crystal director alignment, and grating layer thickness. 
     
     
         14 . The method of  claim 1 , wherein the predefined grating characteristic results in a grating after exposure, the grating having a spatially varying diffraction efficiency. 
     
     
         15 . A system for fabricating a grating, the system comprising:
 at least one deposition head connected to at least one reservoir containing at least one mixture of optical recording material;   a first substrate having at least one predefined region for supporting gratings;   a positioning element capable of positioning the at least one deposition head across the first substrate, wherein:
 the at least one deposition head is configured to deposit the at least one mixture of optical recording material onto the first substrate using the positioning element; and 
 the deposited material provides a predefined grating characteristic within the at least one predefined grating region after holographic exposure. 
   
     
     
         16 . The system of  claim 15 , wherein the at least one deposition head is connected to a first reservoir containing a first mixture of optical recording material and a second reservoir containing a second mixture of optical recording material. 
     
     
         17 . The system of  claim 16 , wherein the first mixture of optical recording material comprises a liquid crystal and a monomer; and the second mixture of optical recording material comprises a monomer; wherein the at least one deposition head is configured to deposit the first mixture of optical recording material onto the at least one predefined grating region. 
     
     
         18 . The system of  claim 15 , wherein the at least one deposition head comprises at least one inkjet print head. 
     
     
         19 . The system of  claim 15 , wherein the predefined grating characteristic comprises a characteristic selected from the group consisting of: refractive index modulation, refractive index, birefringence, liquid crystal director alignment, and grating layer thickness. 
     
     
         20 . The system of  claim 15 , wherein the predefined grating characteristic results in a grating after exposure, the grating having a spatially varying diffraction efficiency.