Optical diffraction gratings and methods for manufacturing same
Described herein are diffraction gratings and methods for the manufacture thereof. One method comprises applying a force to a substrate to strain the substrate, disposing a thin film on at least a portion of the substrate, and reducing the force applied to the substrate, thereby causing the thin film to buckle.
1. A method for making an optical grating, comprising:
(a) applying a force to a substrate to strain the substrate; wherein applying a force comprises stretching the substrate;
(b) disposing a thin metal film on at least a portion of the substrate; and
(c) reducing the force applied to the substrate, thereby causing the thin film to buckle.
2. The method of claim 1 , wherein the substrate comprises an elastomer.
3. The method of claim 1 , wherein the substrate comprises polydimethylsiloxane.
4. The method of claim 1 , wherein the thin film has a thickness of about 5 to about 500 nm.
5. The method of claim 1 , wherein the thin film has a thickness of about 5 to about 200 nm.
6. The method of claim 1 , wherein the thin film is disposed on the substrate in a pre-defined pattern.
7. The method of claim 1 , wherein the thin film is disposed on the substrate using a sputtering technique.
8. The method of claim 1 , wherein reducing the force applied to the substrate comprises substantially removing the force from the substrate.
9. The method of claim 1 , wherein the thin film is caused to buckle in a substantially periodic shape.
10. The method of claim 1 , wherein the thin film is caused to buckle in a substantially sinusoidal pattern.
11. A method for making an optical grating, comprising:
(a) providing a strained substrate by applying a force comprising stretching the substrate;
(b) disposing a thin metal film on at least a portion of the strained substrate; and
(c) reducing a force applied to the substrate, thereby causing the thin film to buckle.
12. The method of claim 11 , wherein the substrate comprises an elastomer.
13. The method of claim 11 , wherein the substrate comprises polydimethylsiloxane.
14. The method of claim 11 , wherein the thin film has a thickness of about 5 to about 500 nm.
15. The method of claim 11 , wherein the thin film is caused to buckle in a substantially periodic shape.
16. The method of claim 11 , wherein the thin film is caused to buckle in a substantially sinusoidal pattern.
17. An optical grating comprising:
an elastomeric substrate; and
a thin film disposed on at least a portion of the substrate, the thin film comprising a metal and having a periodic shape,
and wherein operating temperature of the optical grating is in a range from about −45° C. to about 200° C., and wherein the temperature change results in less than 1.7% change in buckling period.