Abstract: A substantially uninterruptible backup power system to provide power to common household appliances comprises a rechargeable battery, a trickle-charging circuit to keep the battery fully charged at all times from the receptacle power, a DC to AC inverter to supply standard AC line voltage from the battery to the lamp, a relay switch, controlled by main power voltage, to switch to the backup system when main power fails, and a timing circuit to optimize a voltage output of the system based on current battery voltage and a desired time period for the voltage output. The system can be set to operate only when the appliance is turned on, which optimizes the current and power required to provide backup power to the appliance for a maximum period of time.

Abstract: A multi-wavelength etalon suitable for tuning and maintaining the operating frequency of a laser used in an optical communication system is disclosed. The communication system has a representative channel wavelength and a channel spacing. The etalon has a plurality of steps on one of the sides with a step size that is a fraction of the channel spacing. The nominal thickness of the etalon is chosen so that a transmission peak occurs at a wavelength substantially equal to the representative channel wavelength and a next peak occurs at the wavelength of an adjacent channel. The step size is a fraction of the channel separation and is substantially optimized so that a peak or trough in the transmission curve in the region of one step overlaps a steep portion of the transmission curve for one or more other steps.

Abstract: A raised photodetector constructed to define an open channel extending between opposite edges of the photodetector and dimensioned for permitting light from laser to pass therethrough. The photodetector has a light-collecting region disposed in an outward facing wall recessed within the channel for collecting light from the laser.

Abstract: The present invention is a method for compensating for stress induced in optical components used to couple light egressing from the housing of optical modules employing, for example, a distributed optical isolator. It has been discovered that this induced stress may be counteracted by transmitting a balancing or compensating force so as to produce a counter-stress in the optical component. Preferably, the method uses pairs of circumferential laser welds judiciously formed a distance form the holder housing the optical component so as s to control the magnitude and direction of the applied compensating force and, hence, the counter-stress transmitted to the optical component. During welding, the effects of the induced stress are monitored and based upon any changes therein, pairs of laser welds are formed around the circumferential surface of the housing of the optical component until the induced stress is substantially reduced or eliminated.