Frequency doubling polymeric waveguide

Claim 2

A nonlinear optical waveguide device for frequency doubling of a 700-1300 nm laser beam which comprises a thin film of a polymeric medium which exhibits second order nonlinear optical response, and which has a spatial periodic structure for quasi-phase matching of propagating wave energy, wherein the coherence length l c of the periodic polymeric medium is defined by the equation: l.sub.c =(π/Δβ) where Δβ is the propagation constant difference which is equal to β o (2ω 1 )-2β o (ω 1 ), ω 1 is the fundamental frequency, and subscript zero denotes the zero-ordered mode in the waveguide.

Claim 3

A nonlinear optical waveguide device for frequency doubling of a 700-1300 nm laser beam which comprises a thin film of a polymeric medium which exhibits second order nonlinear optical response, and which has a spatial periodic structure for quasi-phase matching of propagating wave energy; wherein the coherence length l c of the periodic polymeric medium is defined by the equation: l.sub.c =(π/Δβ) where Δβ is tne propagation constant difference which is equal to β o (2ω 1 )-2β o (ω 1 ), ω 1 is the fundamental frequency, and subscript zero denotes the zero-ordered mode in the waveguide; and wherein the polymeric medium comprises a polymer having side chains which exhibit second order nonlinear optical susceptibility and consist of at least 25 weight percent of the polymer, and the side chains have an external field-induced molecular orientation orthogonal to the waveguide plane.

Claim 4

A nonlinear optical waveguide device for frequency doubling of a 700-1300 nm laser beam which comprises a thin film of a polymeric medium which exhibits second order nonlinear optical response, and which has a spatial periodic structure for quasi-phase matching of propagating wave energy; wherein the coherence length l c of the periodic polymeric medium is defined by the equation: l.sub.c =(π/Δβ) where Δβ is tne propagation constant difference which is equal to β o (2ω 1 )-2β o (ω 1 ), ω 1 is the fundamental frequency, and subscript zero denotes the zero-ordered mode in the waveguide; and wherein the polymeric medium comprises a polymer having side chains which exhibit second order nonlinear optical susceptibility and consist of at least 25 weight percent of the polymer, and the side chains have an external field-induced molecular orientation orthogonal to the waveguide plane.

Claim 5

A waveguide device in accordance with claim 2 wherein the polymeric thin film is coated on a support substrate.

Claim 6

A waveguide device in accordance with claim 2 wherein the polymeric thin film comprises a thermotropic liquid crystalline polymer having a comb structure of mesogenic side chains, and having a glass transition temperature above about 40° C.

Claim 7

A waveguide device in accordance with claim 2 wherein the polymeric thin film comprises a polymer with a main chain polyvinyl structure.

Claim 8

A waveguide device in accordance with claim 2 wherein the polymeric thin film comprises a polymer with a main chain polysiloxane structure.

Claim 9

A waveguide device in accordance with claim 2 wherein the polymeric thin film comprises a polymer with a main chain polyoxyalkylene structure.

Claim 10

A waveguide device in accordance with claim 2 wherein the polymeric thin film comprises a polymer with a main chain polyester or polyamide structure.

Claim 11

A waveguide device in accordance with claim 2 wherein the polymeric thin film comprises a polymer which is characterized by a recurring monomeric unit corresponding to the formula: ##STR4## where P' is a polymer main chain unit, S' is a flexible spacer group having a linear chain length of between about 0-20 atoms, M' is a pendant group which exhibits second order nonlinear optical susceptibility, and where the pendant side chains consist of at least about 25 weight percent of the polymer, and the polymer has a glass transition temperature above about 40° C.

Claim 12

A waveguide device in accordance with claim 9 wherein the M' group contains a biphenyl structure.

Claim 13

A waveguide device in accordance with claim 9 wherein the M' group contains a stilbene structure.

Claim 14

A frequency converting module for producing a short wavelength laser beam which comprises: a. a 700-1300 nm laser generating source, in coupled combination with b. an optical waveguide comprising a substrate-supported thin film of a polymeric medium which exhibits second order nonlinear optical response, and which has a spatial periodic structure for quasi-phase matching of propagating wave energy; wherein the coherence length l c of the periodic polymeric medium is defined by the equation: l.sub.c =(π/Δβ) where Δβ is the propagation constant difference which is equal to β o (2ω 1 )-2β o (ω 1 ), ω 1 is the fundamental frequency, and subscript zero denotes the zero-ordered mode in the waveguide; and wherein the polymeric medium comprises a polymer having side chains which exhibit second order nonlinear optical susceptibility and consist of at least 25 weight percent of the polymer, and the side chains have an external field-induced molecular orientation orthogonal to the waveguide plane.

Claim 15

A frequency converting module for producing a short wavelength laser beam which comprises: a. a 700-1300 nm laser generating source, in coupled combination with b. an optical waveguide comprising a substrate-supported thin film of a polymeric medium which exhibits second order nonlinear optical response, and which has a spatial periodic structure for quasi-phase matching of propagating wave energy; wherein the coherence length l c of the periodic polymeric medium is defined by the equation: l.sub.c =(π/Δβ) where Δβ is the propagation constant difference which is equal to β o (2ω 1 )-2β o (ω 1 ), ω 1 is the fundamental frequency, and subscript zero denotes the zero-ordered mode in the waveguide; and wherein the polymeric medium comprises a polymer having side chains which exhibit second order nonlinear optical susceptibility and consist of at least 25 weight percent of the polymer, and the side chains have an external field-induced molecular orientation orthogonal to the waveguide plane.

Claim 16

A frequency converting module in accordance with claim 12 wherein the optical waveguide component has a two-dimensional channel structure for single mode wave transmission.

Claim 17

A process for providing a short wavelength laser source which comprises (1) introducing a 700-1300 nm laser beam into an optical waveguide comprising a substrate-supported thin film of a polymeric medium which exhibits second order nonlinear optical response, and which has a spatial periodic structure for quasi-phase matching of propagating wave energy; wherein the coherence length l c of the periodic polymeric medium is defined by the equation: l.sub.c =(π/Δβ) where Δβ is the propagation constant difference which is equal to β o (2ω 1 )-2β o (ω 1 ), ω 1 is the fundamental frequency, and subscript zero denotes the zero-ordered mode in the waveguide; and wherein the polymeric medium comprises a polymer having side chains which exhibit second order nonlinear optical susceptibility and consist of at least 25 weight percent of the polymer, and the side chains have an external field-induced molecular orientation orthogonal to the waveguide plane; and (2) doubling the frequency of the propagating wave energy to provide an output 350-650 nm laser beam.

Claim 18

A process for providing a short wavelength laser source which comprises (1) introducing a 700-1300 nm laser beam into an optical waveguide comprising a substrate-supported thin film of a polymeric medium which exhibits second order nonlinear optical response, and which has a spatial periodic structure for quasi-phase matching of propagating wave energy; wherein the coherence length l c of the periodic polymeric medium is defined by the equation: l.sub.c =(π/Δβ) where Δβ is the propagation constant difference which is equal to β o (2ω 1 )-2β o (ω 1 ), ω 1 is the fundamental frequency, and subscript zero denotes the zero-ordered mode in the waveguide; and wherein the polymeric medium comprises a polymer having side chains which exhibit second order nonlinear optical susceptibility and consist of at least 25 weight percent of the polymer, and the side chains have an external field-induced molecular orientation orthogonal to the waveguide plane; and (2) doubling the frequency of the propagating wave energy to provide an output 350-650 nm laser beam.

Claim 19

A process in accordance with claim 14 wherein the input laser beam is in a transverse magnetic (TM) polarization mode.

Claim 20

A process in accordance with claim 14 wherein the input laser beam power is between about 0.1-1 watt, and the output laser beam power is at least about one milliwatt.

Claim 21

A process in accordance with claim 14 wherein the propagating mode of the input wave energy is zero-ordered.

Claim 22

A process in accordance with claim 14 wherein the waveguide polymeric thin film exhibits a second order nonlinear optical susceptibility χ.sup.(2) of at least about 1×10 -8 esu.

Claim 23

A process in accordance with claim 14 wherein the waveguide polymeric thin film comprises a polymer which is characterized by a recurring monomeric unit corresponding to the formula: ##STR5## where P' is a polymer main chain unit, S' is a flexible spacer group having a linear chain length of between about 0-20 atoms, M' is a pendant group which exhibits second order nonlinear optical susceptibility, and where the pendant side chains consist of at least about 25 weight percent of the polymer, and the polymer has a glass transition temperature above about 40° C.

Claim 24

A process in accordance with claim 19 wherein the M' group contains a biphenyl structure.

Claim 25

A process in accordance with claim 20 wherein the M' group contains a stilbene structure.

Claim 26

A process in accordance with claim 14 wherein the waveguide polymeric thin film comprises a polymer which is characterized by a recurring monomeric unit corresponding to the formula: ##STR6## where m is an integer of at least 5; n is an integer between about 4-20; X is --NR--, --O-- or --S--; R is hydrogen or a C 1 -C 4 alkyl; and Z is --NO 2 , --CN or --CF 3 .

Claim 27

A process in accordance with claim 22 wherein the polymer exhibits liquid crystalline properties.