Abstract: An optical sensor for detecting a chemical in a sample region includes an emitter for producing light, and for directing the light through the sample region. The sensor also includes a detector for receiving the light after the light passes through the sample region, and for producing a signal corresponding to the light the detector receives. The sensor further includes a thermo-optic filter disposed between the emitter and the detector. The optical filter has a tunable passband for selectively filtering the light from the emitter. The passband of the optical filter is tunable by varying a temperature of the optical filter. The sensor also includes a controller for controlling the passband of the optical filter and for receiving the detection signal from the detector. The controller modulates the passband of the optical filter and analyzes the detection signal to determine whether an absorption peak of the chemical is present.

Abstract: An apparatus for depositing films on a substrate, the apparatus including: a plasma deposition chamber having a first electrode and a second electrode that defines a target plane in which the substrate is held during deposition, and wherein during deposition a plasma is sustained between the first and second electrodes, said deposition chamber also including an input window and an output window; and a monitoring system which includes a light source and an optical detector, both located outside of the deposition chamber, said optical monitoring system also including an optical system that directs a beam from the light source through the input window and into the deposition chamber as a measurement beam, wherein the measurement beam arrives at the target plane along a path that is approximately normal to the target plane and wherein during operation said measurement beam interacts with the substrate to generate a return measurement beam that passes from the substrate out of the chamber through the output window

Abstract: According to various embodiments and aspects of the present invention, there is provided a dynamically tunable thin film interference coating including one or more layers with thermo-optically tunable refractive index. Tunable layers within thin film interference coatings enable a new family of thin film active devices for the filtering, control, modulation of light. Active thin film structures can be used directly or integrated into a variety of photonic subsystems to make tunable lasers, tunable add-drop filters for fiber optic telecommunications, tunable polarizers, tunable dispersion compensation filters, and many other devices.