Abstract: A reconfigurable non-blocking Optical Add/Drop Module (OADM). The OADM is tunable to drop one or more target channels from an optical signal without interfering with any channels between a starting channel and the dropped channels. During tuning, all of the channels in the optical signal are expressed. In one embodiment of the OADM, two tunable optical filters are optically coupled in a cascade series such that one or more channels may be dropped by tuning both to the dropped channels. The optical filters are electronically coupled to a common controller that controls the operation of each of the tunable filters. The filters are tuned separately to reach the target dropped channels without interfering with any intermediate channels.

Abstract: An angle tunable thin film interference optical filter for wavelength multiplexing and demultiplexing. The optical filter may be used in an OADM to drop one or more target channels from an optical signal without interfering with any channels between a starting channel and the dropped channels. During tuning, all of the channels in the optical signal are expressed. In one embodiment of the optical filter, a filter is fixedly coupled to a tiltable filter stage. Reflections from the filter are collected by a corner mirror for reflection back to the filter. In another embodiment, a plurality of optical elements are coupled to rotationally coupled carousels. In another embodiment, tunable thin film interference optical filters are coupled to rotationally independent carousals for expanded wavelength coverage.

Abstract: A reconfigurable non-blocking Optical Add/Drop Module (OADM) using linearly variable thin film optical filters. The OADM is tunable to drop one or more target channels from an optical signal without interfering with any channels between a starting channel and the dropped channels. During tuning, all of the channels in the optical signal are expressed. In one embodiment of the OADM, two linearly variable thin film optical filters are optically coupled in a cascade series such that one or more channels may be dropped by tuning both to the dropped channels. The optical filters are electronically coupled to a common controller that controls the operation of each of the linearly variable thin film optical filters. The filters are tuned separately to reach the target dropped channels without interfering with any intermediate channels.

Abstract: An external cavity, single mode laser has a semiconductor gain medium, such as a diode laser, and a monolithic prism assembly positioned in an external resonant cavity having a length of 10 mm or less. The monolithic prism assembly includes a transparent substrate carrying a thin film Fabry-Perot interference filter on a face which is tilted to the path of travel of the laser light in the external cavity. Translation of the monolithic prism assembly including transversely to the optical axis provides continuous mode-hop-free tuning of the laser output wavelength. The Such optical devices can be economically mass produced in advantageously small size, having reproducible spectral performance properties held within tight tolerances. Significantly advantageous applications include dense wavelength division multiplexing systems requiring tightly spaced wavelength subranges for each of multiple channels. High wavelength stability against temperature and humidity changes, etc., can be achieved.

Abstract: Laser pumping and flashlamp pumping of apatite crystals such as trivalent neodymium-doped strontium fluorapatite (Sr.sub.5 (PO.sub.4).sub.3 F) emits efficient lasing at both 1.059 and 1.328 .mu.m. The pump sources for the SFAP material doped with Nd.sup.3+ includes pulsed Cr:LiSrAlF.sub.6 tuned to approximately 805.4 nm. Alternatively, similar results occurred using a continuous wave laser source of Ti:sapphire tuned to approximately 805.4 nm. A preferred embodiment includes a resonant cavity with a high reflectivity mirror having a reflectivity of 100% and an output coupler mirror with a reflectivity of less than 100%. An optional tuning component such as a Pockels Cell-Polarizer combination can also be included. The SFAP material doped with Nd.sup.3+ exhibits a large absorption cross section, high emission cross section, and long radiative lifetime.