US3842289A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin film waveguide with a periodically modulated nonlinear optical coefficient
Assignee: California Institute of Technology
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Filing: 1973-05-18
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Granted: 1974-10-15
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Expires: 1993-05-18
Abstract
Abstract A phase matched thin film waveguide supportive of electromagnetic wave energy having angular frequencies is disclosed. In one embodiment, the waveguide includes a sequence of strips each of length A/2 in the direction of wave energy propagation and spaced apart from one another a distance A/2, A 2 pi / Delta Beta , where Delta Beta is the phase constant difference required to satisfy the relationship Beta 1 + Beta 2 Beta 3 + Delta Beta , Beta 1, Beta 2 and Beta 3 being, to a first order of approximation, the phase constants respectively of the wave energy. In other embodiments, the spaces between the strips are filled with materials whose nonlinear optical coefficient is either zero or different from the nonlinear optical coefficient of the spaced apart strips. The filling material''s index of refraction is substantially equal to that of the spaced apart strips.
Inventors
- 👤 A Yariv
- 👤 S Somekh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:09
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/37; G02F1/377; G02F1/3775; H; H03; H03B; H03B19/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
175 words
A parametric device including: a non-uniform nonlinear thin film waveguide supportive of electromagnetic wave energy having angular frequencies omega 1, omega 2 and omega 3 where omega 1 + omega 2 omega 3, said waveguide comprising a substrate defining a top surface and at least a first group of spaced apart strips of a first material in a form having a nonlinear optical coefficient on the top surface of said substrate, each strip having a length da in the direction of energy propagation, with adjacent strips of each said first group being spaced apart a distance db, where da + db A and A 2 pi / Delta Beta , Delta Beta being the phase difference required to satisfy the phase relationship Beta 1 + Beta 2 Beta 3 + Delta Beta and Beta 1, Beta 2 and Beta 3 are to a first order of approximation, the phase constants respectively of said wave energy, the indicies of refraction of said strips and said substrate being definable as n2 and n3 where n2 < n3.
Claim 2
Dependent Claim
175 words
A parametric device including: a non-uniform nonlinear thin film waveguide supportive of electromagnetic wave energy having angular frequencies omega 1, omega 2 and omega 3 where omega 1 + omega 2 omega 3, said waveguide comprising a substrate defining a top surface and at least a first group of spaced apart strips of a first material in a form having a nonlinear optical coefficient on the top surface of said substrate, each strip having a length da in the direction of energy propagation, with adjacent strips of each said first group being spaced apart a distance db, where da + db A and A 2 pi / Delta Beta , Delta Beta being the phase difference required to satisfy the phase relationship Beta 1 + Beta 2 Beta 3 + Delta Beta and Beta 1, Beta 2 and Beta 3 are to a first order of approximation, the phase constants respectively of said wave energy, the indicies of refraction of said strips and said substrate being definable as n2 and n3 where n2 < n3.
Claim 3
Dependent Claim
88 words
The parametric device ao described in claim 1 wherein said waveguide further includes a second group of spaced apart strips on the top surface of said substrate, each of length db with said first and second groups of strips being in one sequence of strips in which the odd strips consist of said first group and the even strips consist of said second group, each strip in said second group being of a material and in form which is characterized by the absence of a nonlinear optical coefficient.
Claim 4
Dependent Claim
34 words
The parametric device as described in claim 2 wherein said strips of said second group are of said first material in a form different from the form of the strips in said first group.
Claim 5
Dependent Claim
24 words
The parametric device as described in claim 2 wherein said strips of said second group are of a material different from said first material.
Claim 6
Dependent Claim
101 words
The parametric device as described in claim 1 wherein said waveguide further includes a second group of spaced apart strips on said top surface of said substrate, each strip being of a length db with said first and second groups of strips being in one sequence of strips in the direction of energy propagation, with the odd and even strips in the seqence consisting of said first and second groups of strips, respectively, each even strip being of a material and in a form which is characterized by a nonlinear optical coefficient which is different from that of the odd strips.
Claim 7
Dependent Claim
29 words
The parametric device as described in claim 5 wherein each even strip is of a material and form characterized by a nonlinear optical coefficient which is other than zero.
Claim 8
Dependent Claim
36 words
The parametric device ao described in claim 6 wherein the nonlinear optical coefficient of each even strip is characterized by a polarity which is opppsoite the polarity of the nonlinear optical coefficient of the odd strips.
Claim 9
Dependent Claim
22 words
The parametric device as described in claim 1 wherein A is in the range of one hundred to a few hundred microns.
Claim 10
Dependent Claim
36 words
The parametric device as described in claim 8 wherein the thickness of said strips in a direction perpendicular to the direction of energy propagation is of the order of not more than several tens of microns.
Claim 11
Dependent Claim
22 words
The parametric device as described in claim 2 wherein A is in the range of one hundred to a few hundred microns.
Claim 12
Dependent Claim
22 words
The parametric device as described in claim 5 wherein A is in the range of one hundred to a few hundred microns.
Claim 13
Dependent Claim
166 words
A parametric device including: a non-uniform nonlinear thin film waveguide supportive of electromagnetic wave energy having angular frequencies omega 1, omega 2 and omega 3 where omega 1 + omega 2 omega 3, said waveguide comprising a substrate defining a top surface and a single group of spaced apart strips of a first material in a form having a nonlinear optical coefficient, each strip having a length da in the direction of energy propagation, with adjacent strips of said first group being spaced apart a distance db, where da + db A and A 2 pi / Delta Beta , Delta Beta being the phase difference required to satisfy the phase relationship Beta 1 + Beta 2 Beta 3 + Delta Beta and Beta 1, Beta 2 and Beta 3 are to a first order of approximation, the phase constants respectively of said wave energy, said strips and said substrate being characterized by indicies of refraction definable as n2 and n3 respectively, where n2 < n3.
Claim 14
Dependent Claim
166 words
A parametric device including: a non-uniform nonlinear thin film waveguide supportive of electromagnetic wave energy having angular frequencies omega 1, omega 2 and omega 3 where omega 1 + omega 2 omega 3, said waveguide comprising a substrate defining a top surface and a single group of spaced apart strips of a first material in a form having a nonlinear optical coefficient, each strip having a length da in the direction of energy propagation, with adjacent strips of said first group being spaced apart a distance db, where da + db A and A 2 pi / Delta Beta , Delta Beta being the phase difference required to satisfy the phase relationship Beta 1 + Beta 2 Beta 3 + Delta Beta and Beta 1, Beta 2 and Beta 3 are to a first order of approximation, the phase constants respectively of said wave energy, said strips and said substrate being characterized by indicies of refraction definable as n2 and n3 respectively, where n2 < n3.
References Cited (Backward Citations)
US3384433A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |