Curved graded-index waveguides and methods of making the same
Disclosed is a polymeric waveguide for propagating light therein along width and length dimensions of the polymeric waveguide. The polymeric waveguide has a first curved surface on one side thereof and a second curved surface on an opposite second side thereof, and a refractive index spatially varying through a thickness thereof between the first curved surface and the second curved surface. The polymeric waveguide is curved in a cross-section comprising at least one of the width and length dimensions.
1. A polymeric waveguide for propagating light therein along width and length dimensions of the polymeric waveguide, the polymeric waveguide comprising:
a concave surface on one side of the polymeric waveguide and a convex surface on an opposite side of the polymeric waveguide; and
a refractive index monotonically decreasing along a thickness dimension of the polymeric waveguide from the concave surface to the convex surface, wherein the polymeric waveguide is curved in a cross-section comprising the thickness dimension and one of the width or length dimensions.
2. The polymeric waveguide of claim 1 wherein the concave and convex surfaces follow a simple curve.
3. The polymeric waveguide of claim 1 wherein the concave and convex surfaces follow a compound curve.
4. The polymeric waveguide of claim 1 comprising one or more of: a polyacrylate, a polyurethane, a polysilicone, a polyester, a polyolefin, a polyamide, a polycarbonate, copolymers thereof, and mixtures thereof.
5. The polymeric waveguide of claim 1 having a length along the length dimension, a width along the width dimension, and a thickness along the thickness dimension, and wherein ratios of the length of the polymeric waveguide to the thickness of the polymeric waveguide and of the width of the polymeric waveguide to the thickness of the polymeric waveguide are both at least 10:1.
6. A polymeric waveguide for propagating light therein along width and length dimensions of the polymeric waveguide, the polymeric waveguide comprising:
a convex surface on one side of the polymeric waveguide and a concave surface on an opposite second side of the polymeric waveguide; and
a refractive index spatially varying along a thickness dimension of the polymeric waveguide from the convex surface to the concave surface, wherein the polymeric waveguide is curved in a cross-section comprising the thickness dimension and one of the width or length dimensions;
wherein the refractive index at the convex surface is lower than the refractive index at the concave surface.