Abstract: There are provided infrared imaging systems and methods for imaging a sample with fluorescent markers. The system includes a light source configured to illuminate a sample-contacting surface. The light source includes first and second illumination modules, each configured to project a corresponding first and second infrared illumination beam towards a sample holder, the infrared illumination beams interacting at an imaging plane to define an illumination area having a rectangular and homogeneous power profile. The system also includes a control unit operatively connected to a motor assembly and to an optomechanical mechanism. The control unit is configured to superimpose the sample plane and the imaging plane at any of the multiple locations within the enclosure. The system includes a detector configured to receive light emitted by the fluorescent markers of the sample upon illumination of the same in the imaging plane when the sample plane is superimposed with the imaging plane.

Abstract: A broadband optical accumulator and tunable narrowband optical source use a microstructured optical fiber into which optical energy is coupled at a first wavelength. The input optical energy is spectrally broadened as it propagates through the fiber, and the output signal is directed to a wavelength separator such as a Bragg grating. A narrowband portion of the output signal is redirected by the grating, while the remainder is reinjected into the fiber. Adjustment of the output wavelength band may be accomplished by changing the incidence angle of the output signal by pivoting the grating. The grating may be located in a housing and surrounded by index matching fluid, and the narrowband portion of the output signal isolated by the grating may be redirected to an output location by a reflector that moves with pivoting of the grating.

Abstract: An apparatus and method for low noise imaging uses an image sensor, such as an EMCCD in which charges are accumulated and shifted out using analog clock signals. A sensor controller generates the clock signals from digital waveforms stored in memory units that provide outputs to digital-to-analog converters that, in turn, convert the signals to analog form. The analog signals are then amplified and applied to the sensor. The specific waveforms are determined by a digital signal processor and stored in the memories, and the desired waveforms are read out the memories using addressing provided by a field-programmable gate array. The clock signals may be sinusoids, or may be more complex waveform shapes, and the waveform shapes may be varied by a user. The clock signal rise times may be made gradual so as to minimize noise contributions.

Abstract: The present invention concerns a method and camera for obtaining a high-contrast image of a predetermined target present in an area under observation. The method involves obtaining an in-band image of the observation area including the target using a filter whose bands are aligned with selected characteristic wavelength bands of the target and an out-of-band image of the observation area excluding the target using the filter with its bands non-aligned with the selected characteristic wavelength bands of the target. Processing of the in-band and out-of-band images results in a high-contrast image highlighting the presence of the target in the observation area and thereby allowing its detection and monitoring.

Abstract: A laser induced breakdown spectroscopy (LIBS) system uses discrete optical filters for isolated predetermined spectral components from plasma light created by ablation of a sample. Independent detection elements may be used for detecting the magnitude for each spectral component. A first spectral component may include a characteristic wavelength of the sample, while a second spectral component may be a portion of a background continuum. The filters may include volume Bragg gratings and the detectors may be photodiodes. A detector that detects plasma light remaining after the isolation of the predetermined spectral components may be used together with a signal acquisition controller to precisely control the initiation and termination of signal acquisition from each of the detection elements. The system may also have optics including a collimating lens through which passes both the initial plasma light and the isolated spectral components.

Abstract: An apparatus and method for low noise imaging uses an image sensor, such as an EMCCD in which charges are accumulated and shifted out using analog clock signals. A sensor controller generates the clock signals from digital waveforms stored in memory units that provide outputs to digital-to-analog converters that, in turn, convert the signals to analog form. The analog signals are then amplified and applied to the sensor. The specific waveforms are determined by a digital signal processor and stored in the memories, and the desired waveforms are read out the memories using addressing provided by a field-programmable gate array. The clock signals may be sinusoids, or may be more complex waveform shapes, and the waveform shapes may be varied by a user. The clock signal rise times may be made gradual so as to minimize noise contributions.

Abstract: A notch filter system, where multiple filter passes of a light signal may be effected for removing a target spectral component from the light signal, is provided. Advantageously, the notch filter system may be tunable. A cascade notch filter system is provided which includes multiple notch filters arranged in a cascade, each of the filters having spectral filtering characteristics and being disposed in the path of the light signal at an appropriate filter angle so that the target spectral component is filtered out of the light signal as the light signal passes therethrough. A multipass notch filter system is provided which includes a notch filter having spectral filtering characteristics, and an optical assembly for directing the light signal for multiple filter passes through the filter at an appropriate angle, so that the target spectral component is filtered out of the light signal as the light signal passes through the filter.

Abstract: The present invention concerns a method and camera for obtaining a high-contrast image of a predetermined target present in an area under observation. The method involves obtaining an in-band image of the observation area including the target using a filter whose bands are aligned with selected characteristic wavelength bands of the target and an out-of-band image of the observation area excluding the target using the filter with its bands non-aligned with the selected characteristic wavelength bands of the target. Processing of the in-band and out-of-band images results in a high-contrast image highlighting the presence of the target in the observation area and thereby allowing its detection and monitoring.