Mode insensitive waveguide device
AssigneeEastman Kodak Company
InventorsJohn C. Brazas, Jr., Glenn E. Kohnke
Life of this patent
Estimating the term…
Abstract
A waveguide structure includes a substrate, a waveguide film, and an overlay material in contact with the waveguide film. The overlay material may also contact the substrate or the film may be disposed between the overlay and the substrate. The overlay material has a higher refractive index than the waveguide so that the ratio of the effective refractive indexes is substantially constant for all propagating modes supported by the waveguide.
Claims20
An optical device, comprising:
- a waveguide having a film, said film having a first film and a second film boundary spaced from said first film boundary, said waveguide internally reflecting an electromagnetic wave at said film boundaries, said wave being characterized by a projected wave vector, .beta., on a z axis, where ##EQU3## and where .lambda. is the wavelength of light, n.sub.w is the waveguide refractive index, and .phi..sub.m represents the propagation angles supported by said waveguide for defined modes, m, so that an effective refractive index, N.sub.wm, of said waveguide is a function of .phi. and n.sub.w where
- N.sub.m =n.sub.w sin .phi..sub.m ;
- and
- an overlay material positioned on said waveguide film and having a higher refractive index than said waveguide so that the ratio of the effective refractive indexes is substantially constant for all propagation angles, .phi..sub.m, supported by said waveguide.
An optical device, comprising:
- a waveguide having a substrate and a film formed on said substrate, said film having a first film boundary adjacent said substrate and a second film boundary spaced from said substrate, said waveguide internally reflecting an electromagnetic wave at said film boundaries, said wave being characterized by a projected wave vector, .beta., on a z axis, where ##EQU4## and where .lambda. is the wavelength of light, n.sub.w is the waveguide refractive index, and .phi..sub.m represents the propagation angles supported by said waveguide for defined modes, m, so that an effective refractive index, N.sub.wm, of said waveguide is a function of .phi. and n.sub.w where
- N.sub.m =n.sub.w sin .phi..sub.m ;
- and
- an overlay material positioned on said waveguide film and having a higher refractive index than said waveguide so that the ratio of the effective refractive indexes is substantially constant for all propagation angles, .phi..sub.m, supported by said waveguide.
A waveguide structure, comprising:
- a substrate having a refractive index, n.sub.s ;
- a waveguide film formed on said substrate and having a refractive index, n.sub.w, with n.sub.w being larger than n.sub.s ;
- an overlay material positioned on said waveguide film and having a refractive index, n.sub.ol, with n.sub.ol being larger than n.sub.w ;
- and
A method for fabricating a waveguide structure having a substrate and a waveguide firm formed on the substrate, said substrate having a refractive index n.sub.s, said waveguide film having a refractive index n.sub.w, said method comprising:
- selecting a substrate having a refractive index, n.sub.s ;
- forming a waveguide film having a refractive index, n.sub.w, with n.sub.w being larger than n.sub.s ;
- forming overlay material having a refractive index, n.sub.ol, on the waveguide film with n.sub.ol being larger than n.sub.w ;
- and forming a cladding having a refractive index n.sub.c on said overlay.
A waveguide structure, comprising:
- a substrate having a refractive index, n.sub.s ;
- a waveguide film formed on said substrate having a refractive index, n.sub.w, with n.sub.w being larger than n.sub.s ;
- an overlay material positioned on said waveguide film and having a refractive index, n.sub.ol, with n.sub.ol being larger than n.sub.w, and
- n.sub.w is substantially equal to the average of n.sub.s and n.sub.ol.
A method for fabricating a waveguide structure having a substrate and a waveguide film formed on the substrate, said method comprising:
- selecting a substrate having a refractive index, n.sub.s ;
- forming a waveguide film having a refractive index, n.sub.w, with n.sub.w being larger than n.sub.s ;
- forming overlay material having a refractive index, n.sub.ol, on the waveguide film with n.sub.ol being larger than n.sub.w and n.sub.w being substantially equal to the average of n.sub.s and n.sub.ol.
A method for fabricating a waveguide structure having a substrate and a waveguide film formed on the substrate, said method comprising:
- selecting a substrate having a refractive index, n.sub.s ;
- forming overlay material having a refractive index, n.sub.ol, on the substrate with n.sub.ol being larger than n.sub.s ;
- and
- forming a waveguide film having a refractive index, n.sub.w, on the overlay material, with n.sub.ol being larger than n.sub.w and n.sub.w being substantially equal to the average of n.sub.s and n.sub.ol.
Dependencies are inferred from the claim text.