Abstract: A cavity enhanced optical detector comprising: i) a source of continuous wave laser light; ii) a high finesse resonant cavity comprising at least three spaced apart, high-reflectivity mirrors positioned to receive light from the laser light source; iii) at least one photo-detector for measuring the extinction coefficient of an analyte that is positioned in the resonant cavity; and iv) one or more additional photo-detectors for measuring the intensity of fluorescence emission and/or Raman scattering from the analyte.

Abstract: An apparatus for cavity enhanced optical detection having an improved flow cell is provided. Sensitivity of the cavity resonance condition to changes in refractive index of an analyte flowing through the flow cell is reduced. More specifically, the round trip optical path defined by the resonant cavity intersects a curved cavity input mirror at a point. This point has a location on the input mirror that is substantially independent of the refractive index of the analyte. In this manner, changes in sample refractive index do not lead to misalignment of the resonant optical cavity.

Abstract: A tunable laser and laser tuning method, based on the interaction of a spectrally dependent beam distortion and a spatial filter within a laser cavity. One embodiment of this laser is an external cavity semiconductor laser in which broad tunability is obtained by the insertion of an acousto-optic tunable filter (AOTF) into the laser cavity such that the intra-cavity laser beam passes through the AOTF in zeroth order.

Abstract: A laser tuning mechanism which embodies “spectrally dependent spatial filtering” (SDSF) and contemplates two key elements of the tuning mechanism. The first element of the SDSF tuning mechanism is a spectrally dependent beam distortion (i.e. alteration of the amplitude and/or phase profile of the beam) provided by an SDSF tuning element in a laser cavity. The second element of the SDSF tuning mechanism is an intracavity spatial filter which makes the round trip cavity loss a sensitive function of both beam distortion and cavity alignment. Such a laser can be aligned so that a specific beam distortion, which is provided by the SDSF tuning element at a tunable wavelength, is required to obtain minimum round trip cavity loss, thereby providing tunable laser emission. A preferred embodiment of the SDSF tuning mechanism is an external cavity semiconductor laser having a zeroth order acousto-optic tuning element.

Abstract: A laser tuning mechanism which embodies “spectrally dependent spatial filtering” (SDSF) and contemplates two key elements of the tuning mechanism. The first element of the SDSF tuning mechanism is a spectrally dependent beam distortion (i.e. alteration of the amplitude and/or phase profile of the beam) provided by an SDSF tuning element in a laser cavity. The second element of the SDSF tuning mechanism is an intracavity spatial filter which makes the round trip cavity loss a sensitive function of both beam distortion and cavity alignment. Such a laser can be aligned so that a specific beam distortion, which is provided by the SDSF tuning element at a tunable wavelength, is required to obtain minimum round trip cavity loss, thereby providing tunable laser emission. A preferred embodiment of the SDSF tuning mechanism is an external cavity semiconductor laser having a zeroth order acousto-optic tuning element.

Abstract: A tunable laser and laser tuning method, based on the interaction of a spectrally dependent beam distortion and a spatial filter within a laser cavity. One embodiment of this laser is an external cavity semiconductor laser in which broad tunability is obtained by the insertion of an acousto-optic tunable filter (AOTF) into the laser cavity such that the intra-cavity laser beam passes through the AOTF in zeroth order.

Abstract: A cavity enhanced optical detector comprising: i) a source of continuous wave laser light; ii) a high finesse resonant cavity comprising at least three spaced apart, high-reflectivity mirrors positioned to receive light from the laser light source; iii) at least one photo-detector for measuring the extinction coefficient of an analyte that is positioned in the resonant cavity; and iv) one or more additional photo-detectors for measuring the intensity of fluorescence emission and/or Raman scattering from the analyte.

Abstract: An apparatus for cavity enhanced optical detection comprising: a) a source of optical radiation b) a resonant optical cavity which provides a round trip path for said optical radiation the cavity comprising: i) a plurality of mirrors, the first mirror being an input mirror which receives the optical radiation and inputs it into the cavity; ii) a flow cell positioned within said cavity, said flow cell comprising at least a first analysis channel which accommodates a flow of analyte fluid there through, iii) a second mirror, which second mirror receives the radiation from the optical source after its passage through both said input mirror and said analysis channel and reflects said received radiation.

Abstract: The present invention provides an apparatus for determining a wavelength of an optical signal by determining a coarse wavelength response and a fine wavelength response. The coarse wavelength response is achieved by utilizing an optical filter. A suitable detector detects the wavelength-dependent response and conveys the determined coarse wavelength response to the processing logic. The fine wavelength response is achieved by utilizing an interferometer that is capable of generating an interference pattern. Two detectors are disposed in the interference pattern at a quadrature separation from each other and detect the intensity responses at their respective locations. The intensity responses are conveyed to a unit that determines the fine wavelength response. Finally, the processing logic determines the wavelength utilizing the determined coarse wavelength response and the determined fine wavelength response.

Abstract: The present invention provides an apparatus for determining a wavelength of an optical signal by determining a coarse wavelength response and a fine wavelength response. The coarse wavelength response is achieved by utilizing an optical filter. A suitable detector detects the wavelength-dependent response and conveys the determined coarse wavelength response to the processing logic. The fine wavelength response is achieved by utilizing an interferometer that is capable of generating an interference pattern. Two detectors are disposed in the interference pattern at a quadrature separation from each other and detect the intensity responses at their respective locations. The intensity responses are conveyed to a unit that determines the fine wavelength response. Finally, the processing logic determines the wavelength utilizing the determined coarse wavelength response and the determined fine wavelength response.

Abstract: A laser tuning mechanism which embodies “spectrally dependent spatial filtering” (SDSF) and contemplates two key elements of the tuning mechanism. The first element of the SDSF tuning mechanism is a spectrally dependent beam distortion (i.e. alteration of the amplitude and/or phase profile of the beam) provided by an SDSF tuning element in a laser cavity. The second element of the SDSF tuning mechanism is an intracavity spatial filter which makes the round trip cavity loss a sensitive function of both beam distortion and cavity alignment. Such a laser can be aligned so that a specific beam distortion, which is provided by the SDSF tuning element at a tunable wavelength, is required to obtain minimum round trip cavity loss, thereby providing tunable laser emission. A preferred embodiment of the SDSF tuning mechanism is an external cavity semiconductor laser having a zeroth order acousto-optic tuning element.