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: An apparatus for performing fluxless soldering includes an enclosure having a gas inlet through which an inert gas is introduced to create an inert gas-rich environment. Components are placed in the enclosure via an access port which also functions as a vent for allowing purge gases to vent from the enclosure. In one embodiment, a heating stage is provided in the enclosure which provides sufficient heat to reflow solder provided between two or more components. The inert gas is constantly flowing, or purging the enclosure in order to displace oxygen that would initially be present in the system. The presence of inert gas exclusive of other materials provides an oxygen-free environment, i.e., the inert gases provide a “shield” or environment around the parts to be soldered to inhibit the formation of additional oxides during soldering.

Abstract: A method and fixture for laser bar facet coating are disclosed. A holder for securing devices having surfaces for coating includes first and second channels. A plurality of web slats are received in the channels. The web slats have first and second ends and first and second device engaging surfaces. The ends of the web slats are received in respective channels. The ends of the web slats cooperate with the ends of adjacent web slats. The web slats are secured at one end of the channels and otherwise are movable along the channels between an open position to receive devices therebetween for coating and a closed position in which edges of the web slats engage the devices received therebetween for coating. A bias member may be used to retain the web slats in the closed position gripping the devices for coating. In another embodiment, the invention provides a method for coating surfaces of substantially parallelepiped devices.

Abstract: A method and fixture for laser bar facet coating are disclosed. A holder for securing devices having surfaces for coating includes first and second channels. A plurality of web slats are received in the channels. The web slats have first and second ends and first and second device engaging surfaces. The ends of the web slats are received in respective channels. The ends of the web slats cooperate with the ends of adjacent web slats. The web slats are secured at one end of the channels and otherwise are movable along the channels between an open position to receive devices therebetween for coating and a closed position in which edges of the web slats engage the devices received therebetween for coating. A bias member may be used to retain the web slats in the closed position gripping the devices for coating. In another embodiment, the invention provides a method for coating surfaces of substantially parallelepiped devices.

Abstract: There is disclosed, an optical subassembly includes a platform on which a laser and photodiode are mounted. The laser has a rear facet through which passes a small portion of the light emitted by the laser. The photodiode is mounted on the surface of the platform with a light admitting facet for receiving a portion of the light emitted from the rear facet of the laser being substantially perpendicular to the light emitting facet of the laser. The surface of the platform may include a channel. The channel may be tapered from a narrower end near the laser to a wider end near the photodiode, and may be coated with a light-reflective material.