Optical wavelength tuning via actuation of a fluidic grating
Deformable optical elements may be physically altered through fluid displacement. We imprint a grating surface onto an elastomeric membrane by soft lithography. The membrane is installed as a flexible wall of a sealed fluidic chamber. Injection of excess fluid into the chamber induces expansion of the membrane, effectively varying the groove spacing of the imprinted grating. In transmission experiments using a broadband light source, we are able to achieve a 127.2-nm shift in peak wavelength with an injected fluid volume of 0.56 ml. A paraboloid model of the change in curvature of the grating during expansion accurately describes our experimental results.
Raphael A. Guerrero and Sarah Jaye C. Oliva "Optical wavelength tuning via actuation of a fluidic grating," Optical Engineering 53(2), 025104 (20 February 2014). https://doi.org/10.1117/1.OE.53.2.025104