Abstract: Efficient and effective internal material property monitoring systems and methods are presented. In one embodiment, a method for monitoring variations in an internal material property of an object comprises sensing variations in a characteristic over time and communicating information on the variations in the characteristic from within the object to a remote component, wherein the communication is wireless. The characteristic is related to an internal material property of an object and the variations are sensed from within the object. The characteristic can be related to a parameter associated with the material property. The characteristic can be one of a plurality of characteristics sensed, and the sensed variations are associated with a plurality of various material characteristics of a material in the object (e.g., material properties related to a composite material, etc.). A plurality of data points can be collected and the plurality of data points correspond to the sensing of the characteristic.

Abstract: Efficient and effective internal material property monitoring systems and methods are presented. In one embodiment, a monitoring tag device comprises a sensing component, a wireless unit, and a control component. The sensing component is configured to sense variations in a characteristic over time, wherein the characteristic is related to a material property of an object. The wireless unit is configured to communicate with a remote device, including transmitting information associated with the variations in the characteristic. The control component is coupled to the sensing component, wherein the control component is configured to control the sensing component and the wireless unit, wherein the control component also recognizes an indication of the variations in the characteristic over time.

Abstract: A storage information system is disclosed for keeping archival information on the individual active optoelectronic components that are used in telecommunication equipment. The system involves enclosing a nonvolatile memory chip inside the hermetic package of the active optoelectronic component. A memory chip is used to keep the relevant information about the active optoelectronic component such as serial number, part number and specifications. Sensors can also be included inside the hermetic package to monitor the operating conditions of the optoelectronic component. The information system is capable of storing information that is relevant to the component reliability such as: hours of operation, maximum current or voltage, and maximum temperature. The information storage system has the advantage that the archived information is intimately associated with the optoelectronic component thereby lessening the likelihood that information is lost or tampered with.

Abstract: The effectiveness of reflected light to stabilize the operational characteristics of a semiconductor diode laser varies with the polarization orientation of the reflected light. Stabilization failure can occur if the polarization orientation of the reflected light is orthogonal to the polarization of the light emitted by the laser source. The use of multiple reflectors can reduce the probability of stabilization failure by arranging the reflectors to return to the laser source portions of light having polarization orientations that are statistically independent with respect to each other.

Abstract: A single transverse mode semiconductor laser diode source is designed for employment in an optical transmission link comprising a transmitter module and a receiver module operable under uncooled conditions, i.e., without the need of costly cooling equipment, such as thermoelectric coolers. The optical transmission system includes both the semiconductor laser diode source and the optical receiver module that are both designed to operate uncooled under high frequencies (e.g., GHz range) over a wide temperature range without significant changes in signal bandwidth and at temperatures in excess of 125.degree. C.

Abstract: Optical semiconductor devices with integrated diffraction gratings with higher quality are realized through the use of Al-free grating layers. AlGaAs/GaAs regime optical semiconductor devices, such as laser diodes or optical filters, conventionally utilize an AlGaAs grating layer that has a strong affinity for oxidation. Instead of a Al-containing layer, a quantenary, InGaAsP grating layer is utilized, lattice matched to the underlying AlGaAs/GaAs structure, substantially eliminating any problem of oxide contamination. Also, an Al-free, ternary InGaP grating layer is utilized in the InGaP/InGaAsP/GaAs material regime. The quantum well active region of these devices may also be modified to extend the gain bandwidth of operation of these devices to insure continued operation over a wider temperature range with the wavelength peak of the grating in that the wavelength peak of the grating more assuredly remains within the wavelength operating range of the device.

Abstract: An AlGaInP/GaAs laser diode is disclosed in which the active region is made up of quantum wells that are sufficiently thin (less than 5 nm thick) that the transition energy increase due to quantum confinement of the carriers becomes significant. This allows the quantum well material composition to be selected for compressive strain so that the laser operates in the TE polarization mode, while still obtaining a transition energy of from 1.9-2.0 eV for 620-650 nm laser emission. Quantum barriers have sufficient thickness to confine carriers to the quantum wells. Self-pulsation may be obtained in a heterostructure that also includes a saturable absorption layer proximate to the active region and a ridge structure transversely confining absorption produced carriers in the central section of the absorber layer, while allowing lateral carrier diffusion to side regions where carriers are allowed to leave the absorber layer.

Abstract: An optical transmission link has both a transmitter module and a receiver module operable under uncooled conditions, i.e., without the need of costly cooling equipment, such as thermoelectric coolers. The optical transmission system includes both a semiconductor laser diode source and an optical receiver module that are both designed to operate uncooled under high frequencies (e.g., GHz range) over a wide temperature range without significant changes in signal bandwidth and at temperatures in excess of 125.degree. C. Compensation is provided to reduce the effect of photodiode noise and amplifier noise. In addition, temperature compensation can be provided that provides for overall reduction in receiver noise across the bandwidth of the receiver module through maintenance of a temperature environment optimizing receiver performance.

Abstract: An AlGaInP/GaAs laser diode is disclosed in which the active region is made up of quantum wells that are sufficiently thin (less than 5 nm thick) that the transition energy increase due to quantum confinement of the carriers becomes significant. This allows the quantum well material composition to be selected for compressive strain so that the laser operates in the TE polarization mode, while still obtaining a transition energy of from 1.9-2.0 eV for 620-650 nm laser emission. Quantum barriers have sufficient thickness to confine carriers to the quantum wells. Self-pulsation may be obtained in a heterostructure that also includes a saturable absorption layer proximate to the active region and a ridge structure transversely confining absorption produced carriers in the central section of the absorber layer, while allowing lateral carrier diffusion to side regions where carriers are allowed to leave the absorber layer.