Abstract: A tunable Fabry-Perot filter and a tunable vertical cavity surface emitting laser (VCSEL) are disclosed, where both devices utilize an improved dome structure for creating an internal air gap and improved bias electrode construction for increasing the tuning range of the devices.

Abstract: Apparatus and method for stabilizing the wavelength of a tunable laser to a target wavelength, by correspondingly adjusting the electrooptical performance of the laser's gain medium, whereby to eliminate the frequency shift due to vibrational factors. The electrooptical performance of the laser's gain medium is adjusted, in the case of an electrically pumped laser, by changing the injection current used to pump the laser; and the electrical performance of the laser's gain medium is adjusted, in the case of an optically pumped laser, by changing the intensity of the pump laser used to energize the laser. The system is implemented with a feedback mechanism.

Abstract: A method for modulating the output of an optically pumped, tunable VCSEL. Two approaches are disclosed. In a first approach, the output of the VCSEL is modulated by modulating the pump laser. In a second approach, the output of the VCSEL is modulated by modulating a voltage applied across the active region.

Abstract: A wavelength monitoring system for continuously monitoring the wavelengths of different optical channels transmitted through a wavelength division multiplexed (WDM) fiberoptic system. In one construction, an optical diffraction grating is used to disperse the light being monitored onto a rotating polygon having mirrors on the facets thereof, such that the rotating polygon reflects the light onto a detector located behind a slit. In a second construction, the light is projected onto a rotating, hollow transparent cylinder having a thin film filter deposited on a surface thereof, wherein the thin film filter comprises a Fabry-Perot structure which has a gap which varies as a function of its position on the rim of the cylinder, such that the varying gap allows for a varying transmission wavelength which varies as a function of angular position. A detector is positioned in the interior of the cylinder to detect light passing through the rotating thin film filter.

Abstract: An electrically tunable Fabry-Perot structure using a deformable multi-layer mirror construction wherein Ga1-aAlaAs, where a<0.1, is used as the sacrificial layer which may be selectively removed using a citric acid enchant. The multi-layer mirrors consist of N and M period of quarter wavelength layers where N and M are integers, or integers plus ½. Further, the mirrors are made from alternating layers of Ga1-xAlxAs, where x>0.96, and a material selected from the group consisting of either Ga1-zAlzAs, where 0.7>Z>0, or Ga1-yAlyAs/Ga1-zAlzAs/Ga1-yAlyAs where 0.7>Z>0 and y>0.5. The Ga1-xAlxAs is wet oxidized by exposing its edge to water in a nitrogen or helium atmosphere at a temperature of between about 360° C. and 450° C. so as to transform it to AlOx. The resulting AlOx layers abut the sacrificial layer and act as etch stops during the formation of a cantilever Fabry-Perot structure by etching of the sacrificial layer.

Abstract: Apparatus is disclosed for providing auxiliary cooling and thermal stability to a temperature sensitive opto-electronic component. The disclosed apparatus comprising a primary thermal control system having a first thermal connection with a primary structure supporting at least one component of an optical system and a second thermal connection being thermally connected with an external environment; and an auxiliary thermal control system having a first thermal connection being thermally connected with the temperature sensitive opto-electronic component, and the auxiliary thermal control system having a second thermal connection being thermally connected with the primary thermal control system whereby the auxiliary thermal control system provides cooling to the temperature sensitive opto-electronic component and the primary thermal control system provides additional cooling to the auxiliary thermal control system through temperature regulation of the primary structure.

Abstract: Apparatus and method for stabilizing the wavelength of a tunable laser to a target wavelength, by correspondingly adjusting the electrooptical performance of the laser's gain medium, whereby to eliminate the frequency shift due to vibrational factors. The electrooptical performance of the laser's gain medium is adjusted, in the case of an electrically pumped laser, by changing the injection current used to pump the laser; and the electrical performance of the laser's gain medium is adjusted, in the case of an optically pumped laser, by changing the intensity of the pump laser used to energize the laser. The system is implemented with a feedback mechanism.

Abstract: A method is provided for fabricating microelectromechanically tunable vertical-cavity surface-emitting lasers with precise lateral and vertical dimensional control. Microelectromechanical tunable vertical cavity surface emitting laser structures are also provided which include a suspended membrane structure made of a dielectric/metal membrane or metal film that supports a cavity-tuning reflective dielectric film stack while being anchored at the perimeter by metal support post(s). Tuning is achieved by translational movement of the cavity-tuning reflective dielectric film stack in a controlled electrostatic field. The current invention deals with the intracavity electrical contacts for current injection for this type of MEM-tunable VCSEL's. The current invention also includes various mechanisms to control the current injection profile so as to ensure single mode operation throughout the tuning range of the MEM-tunable VCSEL's.

Abstract: Novel light switches and attenuators are disclosed. In one form of the invention, a novel 2×2 crossbar switch is formed by positioning a movable reflector intermediate four fiberoptic lines. In another form of the invention, a 1×N switch is formed by providing a plurality of cantilevers each having a reflective surface thereon. In still another form of the invention, a novel light attenuator is formed by positioning a movable arm intermediate two fiberoptic elements.

Abstract: This invention provides a system that combines a wavelength multiplexer with an FM discriminator for chirp reduction and wavelength locker in a filter to produce a wavelength division multiplexed signal with reduced chirp. A partially frequency modulation laser signal is converted into a substantially amplitude modulation laser signal. This conversion increases the extinction ratio of the input signal and further reduces the chirp. A wavelength division multiplexing (WDM) method is used for transmitting high capacity information through fiber optics systems where digital information is carried on separate wavelengths through the same fiber. Separate transmitters normally generate their respective signals that are transmitted at different wavelengths. These signals are then combined using a wavelength multiplexer to transmit the high capacity information through the fiber optic system.

Abstract: A compact wavelength monitoring and control assembly for a narrow band (i.e., laser) source is provided, comprising two narrow bandpass, wavelength selective transmission filter elements of Fabry-Perot structure through which two separate collimated beams from a laser source are directed onto two photodetectors. The spacing of the multiple transmission maxima for one etalon is chosen to match that of the desired set of frequencies to be used for locking purposes. The spacing of the transmission maxima for the second etalon is used, in combination with a dielectric filter, to generate a wavelength fiducial to denote an absolute frequency. The spacing of the second etalon is chosen to be much wider than the frequency grid etalon. A control circuit processes the simultaneously acquired signals from the two detectors as the laser wavelength is varied.

Abstract: Wavelength reference apparatus for use in calibrating a tunable Fabry-Perot filter or a tunable VCSEL, whereby the device may be tuned to a precise, known wavelength, the wavelength reference apparatus comprising an LED, where the LED is chosen so as to have an emission profile which varies with wavelength; an etalon, where the etalon is chosen so as to have a transmission profile which comprises a comb of transmission peaks, with each transmission peak occurring at a precise, known wavelength; and a detector for detecting the light emitted by the LED and passing through the etalon; whereby when a tunable Fabry-Perot filter or tunable VCSEL is positioned between the etalon and the detector, and the device is swept through its tuning range by varying the tuning voltage applied to the device, the known transmission wavelengths established by the LED and the etalon can be correlated to counterpart tuning voltages of the device, whereby to calibrate the device.

Abstract: A tunable Fabry-Perot filter and a tunable vertical cavity surface emitting laser (VCSEL) are disclosed, where both devices utilize an improved dome structure for creating an internal air gap.

Abstract: An optical fiber wavelength reference device for tuning a tunable Fabry-Perot filter and/or a tunable VCSEL to a desired frequency, where the device uses a fiber etalon to generate a pattern of reference frequencies against which the device is tuned.

Abstract: This invention generally relates to an optical filter for a fiber optic communication system. A coupled multi-cavity optical filter may be used, following a directly modulated laser source, and converts a partially frequency modulated signal into a substantially amplitude modulated signal. The optical filter may compensate for the dispersion in the fiber optic transmission medium and may also lock the wavelength of the laser source.

Abstract: This invention generally relates to an optical filter for a fiber optic communication system. An optical filter may be used, following a directly modulated laser source, and converts a partially frequency modulated signal into a substantially amplitude modulated signal. The optical filter may compensate for the dispersion in the fiber optic transmission medium and may also lock the wavelength of the laser source.

Abstract: A low power fiberoptic relay for radio communications. In one form of the invention, a laser is located at one end (i.e., the communication network end) of the relay and a modulator is located at the other end (i.e., the receiver end) of the relay.

Abstract: A wavelength reference device for tuning a tunable Fabry-Perot filter and/or a tunable VCSEL to a desired frequency, where the device uses a modified Michelson interferometer to generate a series of reference frequencies

Abstract: An apparatus and method for orienting a light source with individual or bundled, single- or multi-mode optical fibers so that the light source projects an efficient projection and/or an optimal projection toward at least one optical fiber.

Abstract: A method is provided for fabricating microelectromechanically tunable vertical-cavity surface-emitting lasers and microelectromechanically tunable Fabry-Perot filters with precise lateral and vertical dimensional control. Strained reflective dielectric film(s) are applied to a multiple quantum well structure to electronically band-gap-engineer the quantum wells. Appropriate strain in the reflective dielectric film layers is also used to create appropriate curvature in one of the reflective dielectric film stacks so as to form a confocal cavity between a planar reflective dielectric film layer and the curved reflective dielectric film layer in the vertical cavity surface emitting laser or filter.