Facebook Patent | Fluorene Derivatized Monomers And Polymers For Volume Bragg Gratings
Patent: Fluorene Derivatized Monomers And Polymers For Volume Bragg Gratings
Publication Number: 20200354311
Publication Date: 20201112
Applicants: Facebook
Abstract
The disclosure provides recording materials include fluorene derivatized monomers and polymers for use in volume Bragg gratings, including, but not limited to, volume Bragg gratings for holography applications. Several fluorene structures are disclosed: simply substituted fluorenes, cardo-fluorenes, and spiro-fluorenes. Fluorene derivatized polymers in Bragg gratings applications lead to materials with higher refractive index, low birefringence, and high transparency. Fluorene derivatized monomers/polymers can be used in any volume Bragg gratings materials, including two-stage polymer materials where a matrix is cured in a first step, and then the volume Bragg grating is written by way of a second curing step of a monomer.
RELATED APPLICATION
[0001] This application claims the benefit of, and priority to, U.S. Provisional Patent Application Ser. No. 62/845,258, filed May 8, 2019, which is incorporated by reference herein in its entirety.
FIELD
[0002] Described herein are recording materials for volume holograms, volume holographic elements, volume holographic gratings, and the like, as well as the volume holograms, volume holographic elements, volume holographic gratings produced by writing or recording such recording materials.
BACKGROUND
[0003] Polymeric substrates are disclosed in the art of holographic recording media, including for example photosensitive polymer films. See, e.g., Smothers et al., “Photopolymers for Holography,” SPIE OE/Laser Conference, 1212-03, Los Angeles, Calif., 1990. The holographic recording media described in this article contain a photoimageable system containing a liquid monomer material (the photoactive monomer) and a photoinitiator (which promotes the polymerization of the monomer upon exposure to light), where the photoimageable system is in an organic polymer host matrix that is substantially inert to the exposure light. During writing (recording) of information into the material (by passing recording light through an array representing data), the monomer polymerizes in the exposed regions. Due to the lowering of the monomer concentration caused by the polymerization, monomer from the dark, unexposed regions of the material diffuses to the exposed regions. See, e.g., Colburn and Haines, “Volume Hologram Formation in Photopolymer Materials,” Appl. Opt. 10, 1636-1641, 1971. The polymerization and resulting diffusion create a refractive index change, referred to as .DELTA.n, thus forming the hologram (holographic grating) representing the data.
[0004] Chain length and degree of polymerization are usually maximized and driven to completion in photopolymer systems used in conventional applications such as coatings, sealants, adhesives, etc., usually by using high light intensities, multifunctional monomers, high concentrations of monomers, heat, etc. Similar approaches were used in holographic recording media known in the art by using organic photopolymer formulations high in monomer concentration. See, for example, U.S. Pat. Nos. 5,874,187 and 5,759,721, disclosing “one-component” organic photopolymer systems. However, such one-component systems typically have large Bragg detuning values if they are not precured with light to some extent.
[0005] Improvements in holographic photopolymer media have been made by separating the formation of a polymeric matrix from the photochemistry used to record holographic information. See, for example, U.S. Pat. Nos. 6,103,454 and 6,482,551, disclosing “two-component” organic photopolymer systems. Two-component organic photopolymer systems allow for more uniform starting conditions (e.g., regarding the recording process), more convenient processing and packaging options, and the ability to obtain higher dynamic range media with less shrinkage or Bragg detuning.
[0006] Such two-component systems have various issues that need improvement. For example, the performance of a holographic photopolymer is determined strongly by how species diffuse during polymerization. Usually, polymerization and diffusion are occurring simultaneously in a relatively uncontrolled fashion within the exposed areas. This leads to several undesirable effects: for example, polymers that are not bound to the matrix after polymerization initiation or termination reactions are free to diffuse out of exposed regions of the film into unexposed areas, which “blurs” the resulting fringes, reducing .DELTA.n and diffraction efficiency of the final hologram. The buildup of .DELTA.n during exposure means that subsequent exposures can scatter light from these gratings, leading to the formation of noise gratings. These create haze and a loss of clarity in the final waveguide display. As described herein, for a series of multiplexed exposures with constant dose/exposure, the first exposures will consume most of the monomer, leading to an exponential decrease in diffraction efficiency with each exposure. A complicated “dose scheduling” procedure is required to balance the diffraction efficiency of all of the holograms.
[0007] Generally, the storage capacity of a holographic medium is proportional to the medium’s thickness. Deposition onto a substrate of a pre-formed matrix material containing the photoimageable system typically requires use of a solvent, and the thickness of the material is therefore limited, e.g., to no more than about 150 .mu.m, to allow enough evaporation of the solvent to attain a stable material and reduce void formation. Thus, the need for solvent removal inhibits the storage capacity of a medium.
[0008] In contrast, in volume holography, the media thickness is generally greater than the fringe spacing, and the Klein-Cook Q parameter is greater than 1. See Klein and Cook, “Unified approach to ultrasonic light diffraction,” IEEE Transaction on Sonics and Ultrasonics, SU-14, 123-134, 1967. Recording mediums formed by polymerizing matrix material in situ from a fluid mixture of organic oligomer matrix precursor and a photoimageable system are also known.
[0009] Because little or no solvent is typically required for deposition of these matrix materials, greater thicknesses are possible, e.g., 200 .mu.m and above. However, while useful results are obtained by such processes, the possibility exists for reaction between the precursors to the matrix polymer and the photoactive monomer. Such reaction would reduce the refractive index contrast between the matrix and the polymerized photoactive monomer, thereby affecting to an extent the strength of the stored hologram.
SUMMARY
[0010] The disclosure provides a compound of Formula I:
STR00001
where in Formula I each R.sup.1 to R.sup.10 is independently hydrogen or a substituent including one or more groups selected from optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, optionally substituted heteroarylalkyl, hydroxy, halo, cyano, trifluoromethyl, trifluoromethoxy, nitro, trimethylsilanyl, optionally substituted epoxide, optionally substituted glycidyl, optionally substituted acrylate, optionally substituted methacrylate, –OR.sup.a, –SR.sup.a, –OC(O)–R.sup.a, –N(R.sup.a).sub.2, –C(O)R.sup.a, –C(O)OR.sup.a, –C(O)SR.sup.a, –SC(O)R.sup.a, –OC(O)OR.sup.a, –OC(O)N(R.sup.a).sub.2, –C(O)N(R.sup.a).sub.2, –N(R.sup.a)C(O)OR.sup.a, –N(R.sup.a)C(O)R.sup.a, –N(R.sup.a)C(O)N(R.sup.a).sub.2, –N(R.sup.a)C(NR.sup.a)N(R.sup.a).sub.2, –N(R.sup.a)S(O).sub.tR.sup.a, –S(O).sub.tOR.sup.a, –S(O).sub.tN(R.sup.a).sub.2, –S(O).sub.tN(R.sup.a)C(O)R.sup.a, –O(O)P(OR.sup.a).sub.2, and –O(S)P(OR.sup.a).sub.2; t is 1 or 2; each R.sup.a is independently selected from hydrogen, optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, and optionally substituted heteroarylalkyl; and wherein at least one of R.sup.1 to R.sup.10 includes a polymerizable or crosslinkable group. In some embodiments, the compound has Formula I(a):
STR00002
[0011] In some embodiments, the disclosure provides a compound of Formula I, or a compound of Formula I(a), wherein a substituent includes one or more linking groups selected from –C.sub.1-10 alkyl-, –O–C.sub.1-10 alkyl-, –C.sub.1-10 alkenyl-, –O–C.sub.1-10 alkenyl-, –C.sub.1-10 cycloalkenyl-, –O–C.sub.1-10 cycloalkenyl-, –C.sub.1-10 alkynyl-, –O–C.sub.1-10 alkynyl-, –C.sub.1-10 aryl-, –O–C.sub.1-10 aryl-, –O–, –S–, –C(O)–, –C(O)O–, –OC(O)–, –OC(O)O–, –N(R.sup.b)–, –C(O)N(R.sup.b)–, –N(R.sup.b)C(O)–, –OC(O)N(R.sup.b)–, –N(R.sup.b)C(O)O–, –N(R.sup.b)C(O)N(R.sup.b)–, –N(R.sup.b)C(NR.sup.b)N(R.sup.b)–, –N(R.sup.b)S(O).sub.w–, –S(O).sub.wN(R.sup.b)–, –S(O).sub.wO–, –OS(O).sub.w–, –OS(O)O–, –O(O)P(OR.sup.b)O–, (O)P(O–).sub.3, –O(S)P(OR.sup.b)O–, and (S)P(O–).sub.3, wherein w is 1 or 2, and R.sup.b is independently hydrogen, optionally substituted alkyl, or optionally substituted aryl. In some embodiments, the substituent includes one or more linking groups selected from –(CH.sub.2)–, 1,2 disubstituted phenyl, 1,3 disubstituted phenyl, 1,4 disubstituted phenyl, disubstituted glycidyl, trisubstituted glycidyl, –CH.dbd.CH–, –C.ident.C–, –O–, –S–, –S(O).sub.2–, –C(O)–, –C(O)O–, –OC(O)–, –OC(O)O–, –NH–, –C(O)NH–, –NHC(O)–, –OC(O)NH–, –NHC(O)O–, –SC(O)NH–, –NHC(O)S–, –NHC(O)NH–, –NHC(NH)NH–, –NHS(P).sub.2–, –S(O).sub.2NH–, –S(O).sub.2O–, –OS(O).sub.2–, –OS(O)O–, (O)P(O–).sub.3, and (S)P(O–).sub.3, wherein n is an integer from 1 to 12. In some embodiments, the substituent includes one or more linking groups selected from –(CH.sub.2).sub.2–, 1,4 disubstituted phenyl, –CH.dbd.CH–, –O–, –C(O)–, –C(O)O–, –OC(O)–, –NH–, –C(O)NH–, –NHC(O)–, –OC(O)NH–, –NHC(O)O–, and (S)P(O–).sub.3. In some embodiments, the substituent includes one or more linking groups selected from –(CH.sub.2)–, –(CH.sub.2).sub.2–, –(CH.sub.2).sub.3–, –(CH.sub.2).sub.4–, –(CH.sub.2)–, –(CH.sub.2).sub.6–, 1,4 disubstituted phenyl, disubstituted glycidyl, trisubstituted glycidyl, –CH.dbd.CH–, –O–, –C(O)–, –C(O)O–, –OC(O)–, –NH–, –C(O)NH–, –NHC(O)–, –OC(O)NH–, –NHC(O)O–, –SC(O)NH–, –NHC(O)S–, and (S)P(O–).sub.3. In some embodiments, the substituent includes one or more terminal groups selected from hydrogen, optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, optionally substituted heteroarylalkyl, optionally substituted acrylate, optionally substituted methacrylate, optionally substituted styrene, optionally substituted epoxide, optionally substituted thiirane, optionally substituted glycidyl, optionally substituted lactone, optionally substituted carbonate, hydroxy, halo, cyano, trifluoromethyl, trifluoromethoxy, nitro, and trimethylsilanyl. In some embodiments, the substituent includes one or more terminal groups selected from alkenyl and cycloalkenyl. In some embodiments, the substituent includes one or more terminal groups selected from optionally substituted acrylate, optionally substituted methacrylate, optionally substituted vinyl, and optionally substituted allyl. In some embodiments, the one or more terminal groups are selected from alkenyl, cycloalkenyl, optionally substituted aryl, and optionally substituted heteroaryl. In some embodiments, the one or more terminal groups are selected from optionally substituted acrylate, optionally substituted methacrylate, optionally substituted vinyl, optionally substituted allyl, optionally substituted epoxide, optionally substituted thiirane, optionally substituted glycidyl, and optionally substituted allyl. In some embodiments, the one or more terminal groups are selected from vinyl, allyl, epoxide, thiirane, glycidyl, acrylate, and methacrylate. In some embodiments, the one or more terminal groups are selected from optionally substituted thiophenyl, optionally substituted thiopyranyl, optionally substituted thienothiophenyl, and optionally substituted benzothiophenyl. In some embodiments, the substituent includes one or more terminal groups selected from acrylate and methacrylate. In some embodiments, the polymerizable or crosslinkable group is selected from optionally substituted alkenyl, optionally substituted cycloalkenyl, optionally substituted alkynyl, optionally substituted acrylate, optionally substituted methacrylate, optionally substituted styrene, optionally substituted epoxide, optionally substituted thiirane, optionally substituted glycidyl, optionally substituted lactone, optionally substituted lactam, and optionally substituted carbonate. In some embodiments, the polymerizable or crosslinkable group is selected from vinyl, allyl, epoxide, thiirane, glycidyl, acrylate and methacrylate. In some embodiments, the disclosure provides a compound comprising a substituent comprising at least an aryl group Ar, wherein Ar is selected from substituted phenyl, substituted naphthyl, substituted anthracenyl, substituted phenanthrenyl, substituted phenalenyl, substituted tetracenyl, substituted chrysenyl, substituted triphenylenyl, and substituted pyrenyl. In some embodiments, Ar is selected from 1,2-substituted phenyl, 1,3-substituted phenyl, and 1,4-substituted phenyl. In some embodiments, Ar is 1,4-substituted phenyl.
[0012] In some embodiments,* the substituent comprises one or more groups selected from*
STR00003
[0013] In some embodiments,* the substituent comprises one or more groups selected from*
STR00004## ##STR00005
[0014] In some embodiments the substituent comprises one or more groups selected from:
STR00006
[0015] In some embodiments, the disclosure provides a compound comprising one or more groups selected from:
STR00007## ##STR00008## ##STR00009
[0016] In some embodiments, the compound comprises one or more groups selected from:
STR00010
[0017] In some embodiments, the substituent is selected from:
STR00011
[0018] The disclosure also provides a compound of Formula II:
STR00012
where in Formula II Ar.sup.1 and Ar.sup.2 are independently selected from a bond, optionally substituted alkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, and optionally substituted heteroarylalkyl; each R.sup.1 to R.sup.10 is independently hydrogen or a substituent including one or more groups selected from optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, optionally substituted heteroarylalkyl, hydroxy, halo, cyano, trifluoromethyl, trifluoromethoxy, nitro, trimethylsilanyl, optionally substituted epoxide, optionally substituted glycidyl, optionally substituted acrylate, optionally substituted methacrylate, –OR.sup.a, –SR.sup.a, –OC(O)–R.sup.a, –N(R.sup.a).sub.2, –C(O)R.sup.a, –C(O)OR.sup.a, –C(O)SR.sup.a, –SC(O)R.sup.a, –OC(O)OR.sup.a, –OC(O)N(R.sup.a).sub.2, –C(O)N(R.sup.a).sub.2, –N(R.sup.a)C(O)OR.sup.a, –N(R.sup.a)C(O)R.sup.a, –N(R.sup.a)C(O)N(R.sup.a).sub.2, N(R.sup.a)C(NR.sup.a)N(R.sup.a).sub.2, –N(R.sup.a)S(O).sub.tR.sup.a–S(O)OR.sup.a, –S(O).sub.tN(R.sup.a).sub.2, –S(O).sub.tN(R.sup.a)C(O)R.sup.a, –O(O)P(OR.sup.a).sub.2, and –O(S)P(OR.sup.a).sub.2; t is 1 or 2; each R is independently selected from hydrogen, optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, and optionally substituted heteroarylalkyl; and wherein at least one of R.sup.1 to R.sup.10 includes a polymerizable or crosslinkable group. In some embodiments, the compound has Formula II(a) or Formula II(b):
STR00013
[0019] In some embodiments, in a compound of Formula I, Formula II(a), or Formula II(b), a substituent includes one or more linking groups selected from –C.sub.1-10 alkyl-, –O–C.sub.1-10 alkyl-, –C.sub.1-10 alkenyl-, –O–C.sub.1-10 alkenyl-, –C.sub.1-10 cycloalkenyl-, –O–C.sub.1-10 cycloalkenyl-, –C.sub.1-10 alkynyl-, –O–C.sub.1-10 alkynyl-, –C.sub.1-10 aryl-, –O–C.sub.1-10 aryl-, –O–, –S–, –C(O)–, –C(O)O–, –OC(O)–, –OC(O)O–, –N(R.sup.b)–, –C(O)N(R.sup.b)–, –N(R.sup.b)C(O)–, –OC(O)N(R.sup.b)–, –N(R.sup.b)C(O)O–, –N(R.sup.b)C(O)N(R.sup.b)–, –N(R.sup.b)C(NR.sup.b)N(R.sup.b)–, –N(R)S(O).sub.w–, –S(O).sub.wN(R.sup.b)–, –S(O).sub.wO–, –OS(O).sub.w–, –OS(O)O.sub.w–, –O(O)P(OR.sup.b)O–, (O)P(O–).sub.3, –O(S)P(OR.sup.b)O–, and (S)P(O–).sub.3, wherein w is 1 or 2, and R.sup.b is independently hydrogen, optionally substituted alkyl, or optionally substituted aryl. In some embodiments, the substituent includes one or more linking groups selected from –(CH.sub.2).sub.n–, 1,2 disubstituted phenyl, 1,3 disubstituted phenyl, 1,4 disubstituted phenyl, –CH.dbd.CH–, –C.ident.C–, –O–, –S–, –C(O)–, –C(O)O–, –OC(O)–, –OC(O)O–, –NH–, –C(O)NH–, –NHC(O)–, –OC(O)NH–, –NHC(O)O–, –NHC(O)NH–, –NHC(NH)NH–, –NHS(O).sub.2–, –S(O).sub.2NH–, –S(O).sub.2O–, –OS(O).sub.2–, –OS(O)O–, (O)P(O–).sub.3, and (S)P(O–).sub.3, wherein n is an integer from 1 to 12. In some embodiments, the substituent includes one or more linking groups selected from –(CH.sub.2).sub.2–, 1,4 disubstituted phenyl, –CH.dbd.CH–, –O–, –C(O)–, –C(O)O–, –OC(O)–, –NH–, –C(O)NH–, –NHC(O)–, –OC(O)NH–, –NHC(O)O–, and (S)P(O–).sub.3. In some embodiments, the substituent includes one or more linking groups selected from –(CH.sub.2)–, –(CH.sub.2).sub.2–, –(CH.sub.2).sub.3–, –(CH.sub.2).sub.4–, –(CH.sub.2).sub.5–, –(CH.sub.2).sub.6–, 1,4 disubstituted phenyl, disubstituted glycidyl, trisubstituted glycidyl, –CH.dbd.CH–, –O–, –C(O)–, –C(O)O–, –OC(O)–, –NH–, –C(O)NH–, –NHC(O)–, –OC(O)NH–, –NHC(O)O–, –SC(O)NH–, –NHC(O)S–, and (S)P(O–).sub.3. In some embodiments, the substituent includes one or more terminal groups selected from hydrogen, optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, optionally substituted heteroarylalkyl, optionally substituted acrylate, optionally substituted methacrylate, optionally substituted styrene, optionally substituted epoxide, optionally substituted lactone, optionally substituted carbonate, hydroxy, halo, cyano, trifluoromethyl, trifluoromethoxy, nitro, and trimethylsilanyl. In some embodiments, the substituent includes one or more terminal groups selected from alkenyl and cycloalkenyl. In some embodiments, the substituent includes one or more terminal groups selected from optionally substituted acrylate, optionally substituted methacrylate, optionally substituted vinyl, and optionally substituted allyl. In some embodiments, the substituent includes one or more terminal groups selected from acrylate and methacrylate. In some embodiments, the polymerizable or crosslinkable group is selected from optionally substituted alkenyl, optionally substituted cycloalkenyl, optionally substituted alkynyl, optionally substituted acrylate, optionally substituted methacrylate, optionally substituted styrene, optionally substituted epoxide, optionally substituted thiirane, optionally substituted glycidyl, optionally substituted lactone, and optionally substituted carbonate. In some embodiments, the polymerizable or crosslinkable group is selected from acrylate and methacrylate. In some embodiments, the substituent is selected from:
STR00014
[0020] The disclosure also provides a compound of Formula II(c), Formula II(d), Formula II(e), Formula II(f), Formula II(g), Formula II(h), Formula II(i), or Formula II(j):
STR00015## ##STR00016
[0021] The disclosure also provides a compound of Formula III:
STR00017
where in Formula III each R.sup.101 to R.sup.104 is independently a group of one, two, three, or four independently selected substituents, or no substituent, each substituent independently including one or more groups selected from optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, optionally substituted heteroarylalkyl, hydroxy, halo, cyano, trifluoromethyl, trifluoromethoxy, nitro, trimethylsilanyl, optionally substituted epoxide, optionally substituted glycidyl, optionally substituted acrylate, optionally substituted methacrylate, –OR.sup.a, –SR.sup.a, –OC(O)–R.sup.a, –N(R.sup.a).sub.2, –C(O)R.sup.a, –C(O)OR.sup.a, –C(O)SR.sup.a, –SC(O)R.sup.a, –OC(O)OR.sup.a, –OC(O)N(R.sup.a).sub.2, –C(O)N(R.sup.a).sub.2, –N(R.sup.a)C(O)OR.sup.a, –N(R.sup.a)C(O)R.sup.a, –N(R.sup.a)C(O)N(R.sup.a).sub.2, N(R.sup.a)C(NR.sup.a)N(R.sup.a).sub.2, –N(R.sup.a)S(O).sub.tR.sup.a, –S(O).sub.tOR.sup.a, –S(O).sub.tN(R.sup.a).sub.2, –S(O).sub.tN(R.sup.a)C(O)R.sup.a, (O)P(OR.sup.a).sub.3, (S)P(OR).sub.3, and –(O)P(OR.sup.a).sub.2; t is 1 or 2; each R.sup.a is independently selected from hydrogen, optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, and optionally substituted heteroarylalkyl; and wherein at least one of R.sup.101 to R.sup.104 includes at least one substituent, the at least one substituent including a polymerizable or crosslinkable group.
[0022] In some embodiments, in the compound of Formula III, a substituent includes one or more linking groups selected from –C.sub.1-10 alkyl-, –O–C.sub.1-10 alkyl-, –C.sub.1-10 alkenyl-, –O–C.sub.1-10 alkenyl-, –C.sub.1-10 cycloalkenyl-, –O–C.sub.1-10 cycloalkenyl-, –C.sub.1-10 alkynyl-, –O–C.sub.1-10 alkynyl-, –C.sub.1-10 aryl-, –O–C.sub.1-10 aryl-, –O–, –S–, –C(O)–, –C(O)O–, –OC(O)–, –OC(O)O–, –N(R.sup.a)–, –C(O)N(R.sup.b), –N(R.sup.b)C(O)–, –OC(O)N(R.sup.b)–, –N(R.sup.b)C(O)O–, –N(R.sup.b)C(O)N(R.sup.b)–, –N(R.sup.b)C(NR.sup.b)N(R.sup.b)–, –N(R.sup.b)S(O).sub.w–, –S(O).sub.wN(R.sup.b)–, –S(O).sub.wO–, –OS(O).sub.w–, –OS(O).sub.wO–, –O(O)P(OR.sup.b)O–, (O)P(O–).sub.3, –O(S)P(OR.sup.b)O–, and (S)P(O–).sub.3, wherein w is 1 or 2, and R is independently hydrogen, optionally substituted alkyl, or optionally substituted aryl. In some embodiments, the substituent includes one or more linking groups selected from –(CH.sub.2).sub.n–, 1,2 disubstituted phenyl, 1,3 disubstituted phenyl, 1,4 disubstituted phenyl, –CH.dbd.CH–, –C.ident.C–, –O–, –S–, –C(O)–, –C(O)O–, –OC(O)–, –OC(O)O–, –NH–, –C(O)NH–, –NHC(O)–, –OC(O)NH–, –NHC(O)O–, –NHC(O)NH–, –NHC(NH)NH–, –NHS(O).sub.2–, –S(O).sub.2NH–, –S(O).sub.2O–, –OS(O).sub.2–, –OS(O)O–, (O)P(O–).sub.3, and (S)P(O–).sub.3, wherein n is an integer from 1 to 12. In some embodiments, the substituent includes one or more linking groups selected from –(CH.sub.2).sub.2–, 1,4 disubstituted phenyl, –CH.dbd.CH–, –O–, –C(O)–, –C(O)O–, –OC(O)–, –NH–, –C(O)NH–, –NHC(O)–, –OC(O)NH–, –NHC(O)O–, and (S)P(O–).sub.3. In some embodiments, the substituent includes one or more linking groups selected from –(CH.sub.2)–, –(CH.sub.2).sub.2–, –(CH.sub.2).sub.3–, –(CH.sub.2).sub.4–, –(CH.sub.2).sub.5–, –(CH.sub.2).sub.6–, 1,4 disubstituted phenyl, disubstituted glycidyl, trisubstituted glycidyl, –CH.dbd.CH–, –O–, –C(O)–, –C(O)O–, –OC(O)–, –NH–, –C(O)NH–, –NHC(O)–, –OC(O)NH–, –NHC(O)O–, –SC(O)NH–, –NHC(O)S–, and (S)P(O–).sub.3. In some embodiments, the substituent includes one or more terminal groups selected from hydrogen, optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl, optionally substituted heteroarylalkyl, optionally substituted acrylate, optionally substituted methacrylate, optionally substituted styrene, optionally substituted epoxide, optionally substituted thiirane, optionally substituted glycidyl, optionally substituted lactone, optionally substituted carbonate, hydroxy, halo, cyano, trifluoromethyl, trifluoromethoxy, nitro, and trimethylsilanyl. In some embodiments, the substituent includes one or more terminal groups selected from alkenyl and cycloalkenyl. In some embodiments, the substituent includes one or more terminal groups selected from optionally substituted acrylate, optionally substituted methacrylate, optionally substituted vinyl, and optionally substituted allyl. In some embodiments, the one or more terminal groups are selected from alkenyl, cycloalkenyl, optionally substituted aryl, and optionally substituted heteroaryl. In some embodiments, the one or more terminal groups are selected from optionally substituted acrylate, optionally substituted methacrylate, optionally substituted vinyl, optionally substituted allyl, optionally substituted epoxide, optionally substituted thiirane, optionally substituted glycidyl, and optionally substituted allyl. In some embodiments, the one or more terminal groups are selected from vinyl, allyl, epoxide, thiirane, glycidyl, acrylate, and methacrylate. In some embodiments, the one or more terminal groups are selected from optionally substituted thiophenyl, optionally substituted thiopyranyl, optionally substituted thienothiophenyl, and optionally substituted benzothiophenyl. In some embodiments, the substituent includes one or more terminal groups selected from acrylate and methacrylate. In some embodiments, the polymerizable or crosslinkable group is selected from optionally substituted alkenyl, optionally substituted cycloalkenyl, optionally substituted alkynyl, optionally substituted acrylate, optionally substituted methacrylate, optionally substituted styrene, optionally substituted epoxide, optionally substituted thiirane, optionally substituted glycidyl, optionally substituted lactone, optionally substituted lactam, and optionally substituted carbonate. In some embodiments, the polymerizable or crosslinkable group is selected from acrylate and methacrylate. In some embodiments, the disclosure provides a compound comprising a substituent comprising at least an aryl group Ar, wherein Ar is selected from substituted phenyl, substituted naphthyl, substituted anthracenyl, substituted phenanthrenyl, substituted phenalenyl, substituted tetracenyl, substituted chrysenyl, substituted triphenylenyl, and substituted pyrenyl. In some embodiments, Ar is selected from 1,2-substituted phenyl, 1,3-substituted phenyl, and 1,4-substituted phenyl. In some embodiments, Ar is 1,4-substituted phenyl. In some embodiments, the substituent is selected from:
STR00018
[0023] The disclosure also provides a compound of Formula III(a) and Formula III(b):
STR00019
[0024] The disclosure also provides a resin mixture including a first polymer precursor including a compound of Formula I, Formula I(a), Formula II, Formula I(a), Formula II(b), Formula II(c), Formula II(d), Formula II(e), Formula II(f), Formula II(g), Formula II(h), Formula II(i), Formula II(j), Formula III, or Formula III(a), having any and all corresponding limitations described herein, and a second polymer precursor including a different compound including a polymerizable or crosslinkable group. In some embodiments, the different compound is selected from an alcohol and an isocyanate.
[0025] The disclosure also provides a polymeric material including a resin mixture including a first polymer precursor including a compound of Formula I, Formula I(a), Formula II, Formula II(a), Formula II(b), Formula II(c), Formula II(d), Formula I(e), Formula II(f), Formula (g), Formula II(h), Formula II(i), Formula II(j), Formula III, Formula III(a), or Formula III(b), having any and all corresponding limitations described herein, and a second polymer precursor including a different compound including a polymerizable or crosslinkable group, wherein the second polymer precursor is partially or totally polymerized or crosslinked. In some embodiments, the different compound is selected from an alcohol and an isocyanate. In some embodiments, the first polymer precursor is partially or totally polymerized or crosslinked.
[0026] The disclosure also provides a recording material for writing a volume Bragg grating, the material including a transparent support and a resin mixture including a first polymer precursor including a compound of Formula I, Formula I(a), Formula II, Formula (a), Formula II(b), Formula II(c), Formula II(d), Formula II(e), Formula II(f), Formula I(g), Formula II(h), Formula II(i), Formula II(j), Formula III, Formula III(a), or Formula III(b), having any and all corresponding limitations described herein, and a second polymer precursor including a different compound including a polymerizable or crosslinkable group. In some embodiments, the different compound is selected from an alcohol and an isocyanate. In some embodiments, the material has a thickness of between 1 .mu.m and 500 .mu.m.
[0027] The disclosure also provides a recording material for writing a volume Bragg grating, the material including a polymeric material including a resin mixture including a first polymer precursor including a compound of Formula I, Formula I(a), Formula II, Formula (a), Formula II(b), Formula II(c), Formula II(d), Formula II(e), Formula II(f), Formula (g), Formula II(h), Formula II(i), Formula II(j), Formula III, Formula III(a), or Formula III(b), having any and all corresponding limitations described herein, and a second polymer precursor including a different compound including a polymerizable or crosslinkable group, wherein the second polymer precursor is partially or totally polymerized or crosslinked. In some embodiments, the different compound is selected from an alcohol and an isocyanate. In some embodiments, the first polymer precursor is partially or totally polymerized or crosslinked. In some embodiments, the material has a thickness of between 1 .mu.m and 500 .mu.m.
[0028] The disclosure also provides a volume Bragg grating recorded on any recording material described herein, the grating characterized by a Q parameter equal to or greater than 5,* wherein*
Q = 2 .pi..lamda. 0 d n 0 .LAMBDA. 2 , ##EQU00001##
and wherein .lamda..sub.0 is a recording wavelength, d is the thickness of the recording material, n.sub.0 is a refractive index of the recording material, and .LAMBDA. is a grating constant.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The foregoing summary, as well as the following detailed description of the present disclosure, will be better understood when read in conjunction with the appended drawings.
[0030] FIG. 1 illustrates generic steps for forming a volume Bragg grating (VBG). A raw material can be formed by mixing two different of precursors, e.g., a matrix precursor, and a photopolymerizable imaging precursor. The raw material can be formed into a film by curing or crosslinking, or partially curing or crosslinking the matrix precursor. Finally, holographic exposure initiates the curing or crosslinking of the photopolymerizable precursor which is the main step of the holographic recording process of making a VBG.
[0031] FIG. 2 is a schematic illustrating the various steps included in a controlled radical polymerization for holography applications. The general goals for such applications is the design of a photopolymer material that is sensitive to visible light, produces a large .DELTA.n response, and controls the reaction/diffusion of the photopolymer such that chain transfer and termination reactions are reduced or suppressed. The polymerization reaction that occurs inside traditional photopolymer materials is known as a free radical polymerization, which has several characteristics: radical species are produced immediately upon exposure, radicals initiate polymerization and propagate by adding monomer to chain ends, radicals also react with matrix by hydrogen abstraction and chain transfer reactions, and radicals can terminate by combining with other radicals or reacting with inhibiting species (e.g., O.sub.2).
[0032] FIGS. 3A-3C illustrate generally the concept of using a two-stage photopolymer recording material for volume Bragg gratings, the material including a polymeric matrix (crosslinked lines), and recording, photopolymerizable monomers (circles). As the material is exposed to a light source (arrows, FIG. 3A), the monomer begins to react and polymerize. Ideally, polymerization occurs only in the light exposed areas, leading to a drop in monomer concentration. As the monomer polymerizes, a gradient of monomer concentration is created, resulting in monomer diffusing from high monomer concentration areas, toward low monomer concentration areas (FIG. 3B). As monomer diffuses into exposed regions, stress builds up in the surrounding matrix polymer as it swells and “diffuses” to the dark region (FIG. 3C). If the matrix becomes too stressed and cannot swell to accommodate more monomer, diffusion to exposed areas will stop, even if there is a concentration gradient for unreacted monomer. This typically limits the maximum dynamic range of the photopolymer, since the buildup of .DELTA.n depends on unreacted monomer diffusing into bright regions.
[0033] FIG. 4 illustrates an example of an optical see-through augmented reality system using a waveguide display that includes an optical combiner according to certain embodiments.
[0034] FIG. 5A illustrates an example of a volume Bragg grating. FIG. 5B illustrates the Bragg condition for the volume Bragg grating shown in FIG. 5A.
[0035] FIG. 6A illustrates the recording light beams for recording a volume Bragg grating according to certain embodiments. FIG. 6B is an example of a holography momentum diagram illustrating the wave vectors of recording beams and reconstruction beams and the grating vector of the recorded volume Bragg grating according to certain embodiments.
[0036] FIG. 7 illustrates an example of a holographic recording system for recording holographic optical elements according to certain embodiments.
[0037] FIG. 8 illustrates diffraction efficiency (DE) and Haze (%) as a function of exposure dose (mJ/cm.sup.2) for compound of Formula III (FDUM; experimental conditions: exposure wavelength: 460 nm; reflection-type recording (single beam); film thickness: 50 .mu.m; monomer loading: 15 wt %) according to certain embodiments.
[0038] FIG. 9 illustrates DE and Haze (%) as a function of exposure dose (mJ/cm.sup.2) for comparative compound TPTUM (experimental conditions: exposure wavelength: 460 nm; reflection-type recording (single beam); film thickness: 50 .mu.m; monomer loading: 15 wt %) according to certain embodiments.
DETAILED DESCRIPTION
[0039] Volume gratings, usually produced by holographic technique and known as volume holographic gratings (VHG), volume Bragg gratings (VBG), or volume holograms, are diffractive optical elements based on material with periodic phase or absorption modulation throughout the entire volume of the material. When an incident light satisfies Bragg condition, it is diffracted by the grating. The diffraction occurs within a range of wavelength and incidence angles. In turn, the grating has no effect on the light from the off-Bragg angular and spectral range. These gratings also have multiplexing ability. Due to these properties, VHG/VBG are of great interest for various applications in optics such as data storage and diffractive optical elements for displays, fiber optic communication, spectroscopy, etc.
[0040] Achieving of the Bragg regime of a diffraction grating is usually determined by Klein parameter Q:
Q = 2 .pi..lamda. d n .LAMBDA. 2 , ##EQU00002##
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