Abstract: A method is proposed whereby photo-bleaching is used not only to change the absorption and fluorescence of a sample but is also employed to change its scattering characteristics. When the compounds which are bleached are contained in regions wherein the real part of the index of refraction is greater than or equal to the average index of the medium, the bleaching will result in reduction in the scattering at wavelengths longer than the wavelength of the bleaching source. This reduction can be useful in measuring the concentration of analytes located at significant depths within turbid media.

Abstract: An apparatus for enhancing the selectivity for spectroscopic measurements of analytes in a turbid medium is described. In one example, spatial filters are used to select only certain radii from the medium to be imaged. This selection is accomplished by placing an optical obstruction on the surface of the medium or at an image plane of the surface later in the optical imaging system. In one implementation, this is achieved by placing a fiber bundle at an image plane of the collecting optical system and then using a spacer of appropriate size at the center of the fiber bundle to act as a central obstruction.

Abstract: Weak signals scattered from analytes at multiple wavelengths can be summed to illuminate either a single detector or a multiplicity of detectors, offering the possibility of concentrating the spectral energy on a smaller total detector area. In addition, a method is disclosed whereby a calibration of the resulting signal for a given analyte can be obtained by means of measuring the quantity of water in the sample volume and by means of measuring the salinity of the fluid in the sample volume.

Abstract: An optical apparatus in which multiplexed holograms are used to achieve wavelength selectivity and polarization manipulation is used to facilitate near-normal incidence of light on the holograms. The polarization manipulation allows light reflected from the holograms to be separated from the light incident on the holograms. In one application, the apparatus can be used to extract spectral lines of an analyte from radiation scattered from a sample.

Abstract: Weak signals scattered from analytes at multiple wavelengths can be summed to illuminate either a single detector or a multiplicity of detectors, offering the possibility of concentrating the spectral energy on a smaller total detector area. In addition, a method is disclosed whereby a calibration of the resulting signal for a given analyte can be obtained by means of measuring the quantity of water in the sample volume and by means of measuring the salinity of the fluid in the sample volume.

Abstract: A single mode high power vertical cavity surface emitting laser (VCSEL) using photonic crystals. A photonic crystal is included in at least one mirror layer of a VCSEL. The reflectivity of the photonic crystal is dependent on the wavelength and incident angle of the photons. The photonic crystal can be formed such that the VCSEL lases at a single mode. Because a single mode is generated, the aperture of the VCSEL can be enlarged to increase the power that is generated by the VCSEL for that mode. The photonic crystal can be used with or without DBR layers. The photonic crystal, in one example, forms an external cavity.

Abstract: The present invention relates generally to optoelectronic devices, and particularly to a submount, pedestal, and bond wire assembly for a transistor outline package. A bottom surface of the submount is connected to a top surface of the pedestal. Each bond wire in a bond wire set is connected to a position on the top surface of the submount, and to a position on the signal line. The signal line is positioned a first distance from the position on the top surface of the submount and a second distance from the pedestal. The submount is sized such that a portion of the bottom and the top surface of the submount extends beyond the top surface of the pedestal such that the first distance is less than the second distance.

Abstract: An apparatus is described in which the temperature of a semiconductor laser (or other device) can be set to a desired value by using the heat generated by the laser itself in conjunction with an adjustable thermal impedance heat sink to effect the desired temperature rise.

Abstract: This disclosure concerns systems and devices configured to implement impedance matching schemes in a high speed data transmission environment. In one example, an optoelectronic assembly is provided that includes a TO package having a base through which one or more leads pass. The leads are electrically coupled to an optoelectronic device in the TO package, and are electrically isolated from the base. Some or all of the leads include a ground ring that is electrically isolated from the lead and electrically coupled with the base. A circuit interconnect is also included that is electrically coupled to the optoelectronic device and the TO package. The circuit interconnect includes a dielectric substrate having signal traces that are electrically coupled to the signal leads. A ground signal conductor disposed on the dielectric substrate is electrically coupled with the ground rings.

Abstract: An optical apparatus in which multiplexed holograms are used to achieve wavelength selectivity and polarization manipulation is used to facilitate near-normal incidence of light on the holograms. The polarization manipulation allows light reflected from the holograms to be separated from the light incident on the holograms. In one application, the apparatus can be used to extract spectral lines of an analyte from radiation scattered from a sample.

Abstract: This disclosure concerns optical packages such as may be used in optical transceivers and transmitters. In one example, an optical package includes a header assembly having a base portion to which is attached a header structure that is split into first and second portions that are separated from each other by a space. The header structure further includes one or more electrical leads extending through the base portion and into one of the first and second portions of the header structure. An active temperature control device is included in the optical package and resides in the space between the first and second portions of the header structure. Finally, an optical element, such as a laser, is provided that is arranged for thermal communication with the active temperature control device so that operation of the optical element can be controlled by way of the active temperature control device.

Abstract: A port including a lens for coupling one optical element with another optical element. The lens includes a focusing lens surface that has optical power and a flat lens surface that has little or no optical power. The lens is typically aspherical and couples high angle rays emitted from a source and also introduces aberrations such that the image formed on the receiving optical element is not reflected back to the source optical element. A point is imaged as a spot. The port couples light between optical elements by slightly defocusing the source without impeding the efficiency of the port.

Abstract: A reconfigurable optical add/drop module (ROADM) for dynamically adding or dropping various wavelengths of an optical signal without having to physically replace the module with a wavelength-specific add/drop module, and corresponding methods. A multiplexed optical signal in an optical network enters the reconfigurable optical add/drop module. Filters on the module separate various wavelengths of the optical signal along the module's various waveguides and a reconfigurable switching matrix directs the various wavelengths of the optical signal to be added, dropped and/or combined with other wavelengths.

Abstract: A laser system that can be used to perform manufacturing process such as welding, cutting, drilling and marking a work piece. The laser system includes an array of laser diodes that each generate a laser beam. The laser beams may collectively create a beam that is directed onto the work piece. The system also includes a control circuit that can select and control the laser diodes to vary a characteristic(s) and/or profile of the beam. The control circuit may control the laser diodes so that an outer area of the beam has a higher intensity than an inner area of the beam.

Abstract: An apparatus is described in which the temperature of a semiconductor laser (or other device) can be set to a desired value by using the heat generated by the laser itself in conjunction with an adjustable thermal impedance heat sink to effect the desired temperature rise.

Abstract: Weak signals scattered from analytes at multiple wavelengths can be summed to illuminate either a single detector or a multiplicity of detectors, offering the possibility of concentrating the spectral energy on a smaller total detector area. In addition, a method is disclosed whereby a calibration of the resulting signal for a given analyte can be obtained by means of measuring the quantity of water in the sample volume and by means of measuring the salinity of the fluid in the sample volume.

Abstract: This disclosure concerns systems and devices configured to implement impedance matching schemes in a high speed data transmission environment. In one example, an optoelectronic assembly is provided that includes a TO package having a base through which one or more leads pass. The leads are electrically coupled to an optoelectronic device in the TO package, and are electrically isolated from the base. Some or all of the leads include a ground ring that is electrically isolated from the lead and electrically coupled with the base. A circuit interconnect is also included that is electrically coupled to the optoelectronic device and the TO package. The circuit interconnect includes a dielectric substrate having signal traces that are electrically coupled to the signal leads. A ground signal conductor disposed on the dielectric substrate is electrically coupled with the ground rings.

Abstract: This disclosure concerns systems, methods and devices for temperature-based control of laser performance. One example of a method is performed in connection with a laser of an optoelectronic transceiver. In particular, the laser is operated over a range of temperatures and the optical output of the laser is monitored. During operation of the laser, the bias current and current swing supplied to the laser are adjusted to the extent necessary to maintain a substantially constant optical output from the laser over the range of temperatures.

Abstract: An interference-reducing optoelectronic device determines the value of a current data bit in an optical data stream. A receiver receives the optical data stream, which is converted to a series of samples by a D/A converter. A set of adaptive filters, each filter corresponding to a unique possible value for one or more prior data bits, filters the series of samples utilizing variable tap coefficients to generate filtered output values. The variable tap coefficients are at least partially different than the variable tap coefficients of another adaptive filter. Comparators compare the filtered output values against filter-specific adaptive threshold values to generate tentative values for the current data bit. A delay mechanism delays a determined value for the prior data bits, and a selection mechanism determines the value of the current data bit by selecting the tentative value corresponding to the delayed determined value of the prior data bits.

Abstract: This disclosure concerns optical packages such as may be used in optical transceivers and transmitters. In one example, an optical package includes a header assembly having a base portion to which is attached a header structure that is split into first and second portions that are separated from each other by a space. The header structure further includes one or more electrical leads extending through the base portion and into one of the first and second portions of the header structure. An active temperature control device is included in the optical package and resides in the space between the first and second portions of the header structure. Finally, an optical element, such as a laser, is provided that is arranged for thermal communication with the active temperature control device so that operation of the optical element can be controlled by way of the active temperature control device.