Abstract: An optical system including a gain material pumped by pump energy bands delivered to the gain material from different directions and separated sufficiently to prevent crosstalk between pump energy sources. Embodiments of the pump energy sources may be configured to pump the gain material with pump energy bands that correspond to absorption bands of the gain material.

Abstract: A cavity ring-down spectrometer includes: a) multiple detectors for monitoring the intensity of the radiation emitted from the cavity and the wavelength of the radiation injected into the cavity; b) controllers which turn off the radiation into the cavity and precisely adjust the temperature of, and current to, the laser gain medium; and c) means for adjusting the beam path length of the optical cavit to bring the cavity into resonance with the injected radiation. Additionally, disclosed is a method for using the spectrometer to detect a target analyte.

Abstract: An optical waveguide device is disclosed herein and includes a core having a first index of refraction and configured to propagate at least one optical signal therethrough, the core having a first end and a second end, wherein at least one of the first end and the second end forms a termination angle of about 15 degrees to about 75 degrees, and at least one outer material positioned about the core having a second index of refraction.

Abstract: An enclosure for a cavity enhanced optical spectroscopy instrument provides a highly temperature stable environment by positioning the instrument optical cavity away from the enclosure walls and providing a wall mounted heat pump, fan and heat exchanger. The fan causes the gas contained within the enclosure to circulate over the heat exchanger and in a laminar, non-turbulent flow path along interior wall surfaces of the enclosure thereby maintaining the optical cavity in a temperature and vibration stable zone.

Abstract: A cavity ring-down spectrometer includes: a) multiple detectors for monitoring the intensity of the radiation emitted from the cavity and the wavelength of the radiation injected into the cavity; b) controllers which turn off the radiation into the cavity and precisely adjust the temperature of, and current to, the laser gain medium; and c) means for adjusting the beam path length of the optical cavit to bring the cavity into resonance with the injected radiation. Additionally, disclosed is a method for using the spectrometer to detect a target analyte.

Abstract: A fiber amplifier is disclosed and includes a fiber amplifier body comprising a core of a first diameter, at least one signal conduit in optical communication with a signal source and the fiber amplifier body, the signal conduit sized to the first diameter, and one or more pump conduits configured to propagate pump radiation to the fiber amplifier body, the pump conduits in optical communication with at least one pump source.

Abstract: A mirror translation assembly having a monolithic mirror support member affixed to a monolithic transducer, where these two members have thin sections that are spaced apart from each other and which are deformable by a transducer affixed to the transducer support member, and where the two support members preferably have substantially the same shape. In this manner, a mirror positioned on the mirror support member can be translated without undesirable tilt, while the high stress regions within the assembly are desirably spaced apart from the bond between the two monolithic members.

Abstract: An enclosure for a cavity enhanced optical spectroscopy instrument provides a highly temperature stable environment by positioning the instrument optical cavity away from the enclosure walls and providing a wall mounted heat pump, fan and heat exchanger. The fan causes the gas contained within the enclosure to circulate over the heat exchanger and in a laminar, non-turbulent flow path along interior wall surfaces of the enclosure thereby maintaining the optical cavity in a temperature and vibration stable zone.

Abstract: Methods and apparatus for decreasing the time required to calculate a ring-down time from sampled ring-down data and/or increasing the accuracy of the calculated ring-down time are provided. The time required to obtain an accurate calculation of a ring-down time is reduced by performing a linear least squares fit using an estimate B1 of the background, then using the results of the fit to estimate the error in B1. The estimated error in B1 is then used to provide an improved estimate of the ring-down time. Alternatively, the time required to accurately calculate a ring-down time is reduced by averaging consecutive data points into “bins” and performing a linear least squares fit to the resulting binned signal. The parameters obtained from the fit to the binned signal are then used to obtain an improved estimate B2 of the background, and the ring-down time is calculated by performing a linear least squares fit using B2.

Abstract: A semiconductor pump laser uses a depolarzer to depolarize the pump light entering the fiber amplifier. The depolarized light source is useful for reducing polarization dependent gain of fiber amplifiers. The pump laser includes one or more semiconductor, coherence-collapsed laser sources emitting polarized pump outputs, and one or more depolarizers disposed to depolarize the polarized pump output from the lasers. One or more fiber outputs are coupled to the one or more depolarizers to receive depolarized pump light. The depolarizer may include an N×M polarization preserving coupler having N inputs and M outputs, N and M being at least 2, an input to the depolarizer at a first coupler input, an output port from the depolarizer at a first coupler output. A polarization-controlling optical path is coupled between a second coupler output and a second coupler input.

Abstract: A fiber optic gain system has output power monitoring and control using the detected level of side light emitted through the cladding of the gain fiber. The fiber is wound on a spool that is provided with an opening adjacent to the fiber cladding. A photodetector is mounted to the spool at an opposite side of the opening, and detects side light that is transmitted through the opening. An output signal from the photodetector is indicative of the output power or the gain of the system, and may be used for monitoring and/or to adjust the power generated by a pumping source for the system. This allows feedback control of the system that helps to stabilize the output power or gain. A filtering element may also be used to exclude certain undesired wavelengths from the side light being detected.