Abstract: Spectroscopy systems and methods of comb-based spectroscopy are provided. A light source generates light corresponding to a frequency comb. A prism cavity is optically coupled to the light source. The prism cavity receives the generated light and produces first and second output light. The first output light is associated with reflection of the received light within the prism cavity. The second output light is associated with transmission of the received light through a prism of the prism cavity. A coupling system is coupled to the light source and the prism cavity. The coupling system adjusts a characteristic of at least one of the light source or the prism cavity, based on at least one of the first output light and the second output light. The characteristic is adjusted to increase optical coupling between the light source and the prism cavity and to compensate for a dispersion of the prism cavity.

Abstract: An apparatus and method for controlling a light source used in Cavity Ring-Down Spectroscopy. The apparatus comprises a controller that generates a control signal to activate and deactivate the light source based on a comparison of an energy signal from a resonant cavity and a threshold. The light source is activated for a time period based on the stabilization time of the light source and the time necessary to provide sufficient energy to the resonant cavity. Thereafter the controller deactivates the light source for a predetermined time period by interrupting its current source so that the light energy in the cavity rings down and so that the presence of analyte can be measured. The light energy from the light source is directly coupled to the resonant cavity from the light source.

Abstract: An apparatus and method for analyzing an impurity in a liquid. The apparatus comprises a cell coupled to a light source and a detector. The cell includes a first mirror at a first end of the cell to receive and pass the light into the cell along a longitudinal axis of the cell, and a second mirror at a second end of the cell to at least partially reflect the light. A liquid supply device projects a stream of the liquid between the first mirror and the second mirror and across the longitudinal axis of the cell. The detector is coupled to the second end of the cell and determines a decay rate of the light within the cell based on the light passing through the liquid.