Abstract: Disclosed is a high reflectivity integrating cavity and device to amplify and detect luminescent emissions produced by small concentrations of materials to be analyzed. Femto or nano molar concentrations of a material can be placed within the high reflectivity integrating cavity. At least the interior surface of the high reflectivity integrating cavity can comprise a coating that, at a designated wavelength of electromagnetic radiation, is transparent and non-absorbing to such designated wavelengths of electromagnetic radiation. In addition to the isotropic field induced by the interior surface of the high reflectivity integrating cavity, the high reflectivity of the interior surface of the high reflectivity integrating cavity leads to very large effective optical path lengths within the interior of the high reflectivity integrating cavity, thereby amplifying the luminescent emissions produced by the sample.

Abstract: Disclosed is a high reflectivity integrating cavity and device to amplify and detect luminescent emissions produced by small concentrations of materials to be analyzed. Femto or nano molar concentrations of a material can be placed within the high reflectivity integrating cavity. At least the interior surface of the high reflectivity integrating cavity can comprise a coating that, at a designated wavelength of electromagnetic radiation, is transparent and non-absorbing to such designated wavelengths of electromagnetic radiation. In addition to the isotropic field induced by the interior surface of the high reflectivity integrating cavity, the high reflectivity of the interior surface of the high reflectivity integrating cavity leads to very large effective optical path lengths within the interior of the high reflectivity integrating cavity, thereby amplifying the luminescent emissions produced by the sample.

Abstract: The invention relates an apparatus and method for forming a diffuse reflector. In one embodiment of the invention, a diffuse reflector is formed by exposing transmissive particles of a pre-determined purity to pressure and forming a material having desired diffuse reflective properties. The transmissive particles may further be thermally treated, such as by sintering, to form material having desired diffuse reflective properties. The treated transmissive particles may then be disposed in a vessel and define a cavity therein to form an integrated cavity diffuse reflector.

Abstract: The invention relates an apparatus and method for forming a diffuse reflector. In one embodiment of the invention, a diffuse reflector is formed by exposing transmissive particles of a pre-determined purity to pressure and forming a material having desired diffuse reflective properties. The transmissive particles may further be thermally treated, such as by sintering, to form material having desired diffuse reflective properties. The treated transmissive particles may then be disposed in a vessel and define a cavity therein to form an integrated cavity diffuse reflector.

Abstract: An apparatus for measuring an absorption coefficient includes a first diffusive material, a second diffusive material inside the first diffusive material separated from the first diffusive material by a cavity, and a transparent material proximate to an inner surface of the second diffusive material that holds an absorptive material. First and second light detectors measure light intensities in the first and second diffusive materials respectively. An absorption coefficient for the absorptive material may be determined based on the first and second light intensities measured when the cavity is illuminated by a light source.

Abstract: An apparatus for measuring an absorption coefficient includes a first diffusive material, a second diffusive material inside the first diffusive material separated from the first diffusive material by a cavity, and a transparent material proximate to an inner surface of the second diffusive material that holds an absorptive material. First and second light detectors measure light intensities in the first and second diffusive materials respectively. An absorption coefficient for the absorptive material may be determined based on the first and second light intensities measured when the cavity is illuminated by a light source.

Abstract: A system for detecting an underwater object includes an optical signal generator operable to generate and transmit an optical signal into the water. The system also includes an absorption cell operable to receive the optical signal reflected from the water and absorb an unshifted frequency component of the reflected optical signal. The system further includes a detector operable to receive a shifted frequency component of the optical signal from the absorption cell and detect the object using the shifted frequency component of the optical signal. Displacement of the water by the object causes an absence of a portion of the shifted frequency component of the optical signal.

Abstract: An apparatus for measuring an absorption coefficient includes a first diffusive material, a second diffusive material inside the first diffusive material separated from the first diffusive material by a cavity, and a transparent material proximate to an inner surface of the second diffusive material that holds an absorptive material. First and second light detectors measure light intensities in the first and second diffusive materials cavity and the transparent material respectively. An absorption coefficient for the absorptive material may be determined based on the first and second light intensities measured when the cavity is illuminated by a light source.