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US5011250A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical harmonic generator

Assignee: Sharp Corp
•
Filing: 1989-06-16
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Granted: 1991-04-30
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Expires: 2009-06-16
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Abstract

Abstract An optical harmonic generator for obtaining a harmonic with a wavelength which is an integral measure of the wavelength of incident light by the use of a nonlinear optical effect is provided which is used, for example, to obtain a laser beam having a shorter wavelength. The optical harmonic generator is formed by laminating a dielectric, a metal thin film, and a nonlinear thin film waveguide. A very strong alternating electric field, produced by the electric field enhancement effect of a metal surface plasmon excited by the metal thin film, is applied near the interface between the nonlinear thin film waveguide and the metal thin film, and a harmonic is generated from the nonlinear thin film waveguide by the alternating electric field. By selecting the film thickness of the metal thin film and the depth of the nonlinear thin film waveguide, phase matching between the incident light and the generated harmonic is achieved.

Inventors

  • 👤 Yoshio Okada
  • 👤 Toshihiko Takano

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 02:22
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/37; G02F1/377

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 140 words
An optical harmonic generator comprising: an optical component for emitting light having a propagation constant greater than that of incident light; a metal thin film in which a surface plasmon is excited by the light emitted from said optical component; and a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is 1/N (N: integer equal to or larger than two) of the incident light wavelength, by the surface plasmon of said metal thin film wherein the thickness of said metal thin film and the depth of said waveguide are selected such that the propagation constant of said surface plasmon of said metal thin film is coincident with the propagation constant of the light having the 1/N wavelength with respect to the incident light wavelength and propagating through said waveguide.
Claim 2
Dependent Claim 140 words
An optical harmonic generator comprising: an optical component for emitting light having a propagation constant greater than that of incident light; a metal thin film in which a surface plasmon is excited by the light emitted from said optical component; and a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is 1/N (N: integer equal to or larger than two) of the incident light wavelength, by the surface plasmon of said metal thin film wherein the thickness of said metal thin film and the depth of said waveguide are selected such that the propagation constant of said surface plasmon of said metal thin film is coincident with the propagation constant of the light having the 1/N wavelength with respect to the incident light wavelength and propagating through said waveguide.
Claim 3
Dependent Claim 23 words
The optical harmonic generator according to claim 1, wherein a first dielectric is interposed between said optical component and said metal thin film.
Claim 4
Dependent Claim 26 words
The optical harmonic generator according to claim 2, wherein a second dielectric is arranged on a side of said waveguide opposite to said metal thin film.
Claim 5
Dependent Claim 22 words
The apparatus of claim 1 wherein a dielectric is arranged on a side of said waveguide opposite to said metal thin film.
Claim 6
Dependent Claim 148 words
A frequency conversion apparatus comprising a laser beam source; an optical harmonic generator including an optical component for emitting light having a propagation constant greater than that of incident light; a metal thin film in which a surface plasmon is excited by the light emitted from said optical component; and a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is 1/N (N: integer equal to or larger than two) of the incident light, by the surface plasmon of said metal thin film; wherein the thickness of said metal thin film and the depth of said waveguide are selected such that the propagation constant of said surface plasmon of said metal thin film is coincident with the propagation constant of the light having the 1/N wavelength with respect to the incident light wavelength and propagating through said waveguide.
Claim 7
Dependent Claim 148 words
A frequency conversion apparatus comprising a laser beam source; an optical harmonic generator including an optical component for emitting light having a propagation constant greater than that of incident light; a metal thin film in which a surface plasmon is excited by the light emitted from said optical component; and a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is 1/N (N: integer equal to or larger than two) of the incident light, by the surface plasmon of said metal thin film; wherein the thickness of said metal thin film and the depth of said waveguide are selected such that the propagation constant of said surface plasmon of said metal thin film is coincident with the propagation constant of the light having the 1/N wavelength with respect to the incident light wavelength and propagating through said waveguide.
Claim 8
Dependent Claim 18 words
The frequency conversion apparatus according to claim 3, wherein said laser beam source comprises a solid state laser.
Claim 9
Dependent Claim 17 words
The frequency conversion apparatus according to claim 5 wherein said laser beam source comprises a semiconductor laser.
Claim 10
Dependent Claim 17 words
The frequency conversion apparatus according to claim 5, wherein said laser beam source comprises a gas laser.
Claim 11
Dependent Claim 110 words
An optical harmonic generator comprising: an optical component for emitting light having a propagation constant greater than that of incident light; a metal thin film in which a surface plasmon is excited by the light emitted from said optical component; a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is an integral measure of a frequency of the incident light, by the surface plasmon of said metal thin film; a first dielectric interposed between said optical component and said metal thin film; and a second dielectric arranged on a side of said waveguide opposite to said metal thin film.
Claim 12
Dependent Claim 110 words
An optical harmonic generator comprising: an optical component for emitting light having a propagation constant greater than that of incident light; a metal thin film in which a surface plasmon is excited by the light emitted from said optical component; a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is an integral measure of a frequency of the incident light, by the surface plasmon of said metal thin film; a first dielectric interposed between said optical component and said metal thin film; and a second dielectric arranged on a side of said waveguide opposite to said metal thin film.
Claim 13
Dependent Claim 96 words
An optical harmonic generator comprising: an optical component for emitting light having a propagation constant greater than that of incident light; a metal thin film in which a surface plasmon is excited by the light emitting from said optical component; a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is an integral measure of a frequency of the incident light, by the surface plasmon of said metal thin film; and a dielectric arranged on a side of said waveguide opposite to said metal thin film.
Claim 14
Dependent Claim 96 words
An optical harmonic generator comprising: an optical component for emitting light having a propagation constant greater than that of incident light; a metal thin film in which a surface plasmon is excited by the light emitting from said optical component; a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is an integral measure of a frequency of the incident light, by the surface plasmon of said metal thin film; and a dielectric arranged on a side of said waveguide opposite to said metal thin film.
Claim 15
Dependent Claim 81 words
An optical harmonic generator comprising: an optical component for emitting light having a propagation constant greater than that of incident light; a thin metal film in which a surface plasmon is excited by the light emitted from said optical component; and a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is an integral measure of a frequency of the incident light, by the surface plasmon of said thin metal film.
Claim 16
Dependent Claim 81 words
An optical harmonic generator comprising: an optical component for emitting light having a propagation constant greater than that of incident light; a thin metal film in which a surface plasmon is excited by the light emitted from said optical component; and a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is an integral measure of a frequency of the incident light, by the surface plasmon of said thin metal film.
Claim 17
Dependent Claim 90 words
A frequency conversion apparatus comprising: a laser beam source; an optical harmonic generator including an optical component for emitting light having a propagation constant greater than that of incident light, a thin metal film in which a surface plasmon is excited by the light emitted from said optical component; and a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is an integral measure of a frequency of the incident light, by the surface plasmon of said metal thin film.
Claim 18
Dependent Claim 90 words
A frequency conversion apparatus comprising: a laser beam source; an optical harmonic generator including an optical component for emitting light having a propagation constant greater than that of incident light, a thin metal film in which a surface plasmon is excited by the light emitted from said optical component; and a waveguide including a nonlinear optical thin film for emitting, from an end face thereof, light with a wavelength which is an integral measure of a frequency of the incident light, by the surface plasmon of said metal thin film.

References Cited (Backward Citations)

US4583818A Cited
US4804747A Cited
US4780543A Cited
US4828758A Cited
US5867510A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-04-29 1994-10-29 1995-04-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-04-29 1998-10-29 1999-04-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-04-29 2002-10-29 2003-04-30 $7700.00 Window Closed / Lapsed

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