Abstract: The present invention provides an optical device and a subsystem incorporating the same. In an advantageous embodiment, the optical device includes a signal multiplexer element, and a signal distributor element, both contained within a single optic package unit such that signals introduced therein propagate in free space between the signal multiplexer element and the signal distributor element.

Abstract: An optical fiber that transforms light of undesired polarization into light of desired polarization. In principle, the signal power of the non-preferred polarization is transformed into signal power of the preferred polarization, thereby actually transforming the polarization. The fiber can have a circular end for input of light having randomly phased polarization, and an elongated end for output of light having a single principal orientation component. A generally smooth transition from the circular end to the elongated end causes substantially all the light entering the fiber to exit from the fiber without losing light due to reflection or radiation. Alternatively, the fiber can have a lobed end, for input of light having first and second mutually orthogonal polarization components, and an elongated end, for output of light having a single principal orientation component. Alternatively, the fiber can be a combination of the two forms described above.

Abstract: An optical attenuator includes at least two optical fiber terminations, of which at least one is misaligned, for providing uniform attenuation, which is substantially wavelength independent. At least one of the fiber terminations is misaligned from its position that provides best optical coupling. To accomplish this misalignment, at least one of the fiber terminations is displaced, laterally, longitudinally, or both. This displacement allows only a portion of the incident optical energy to enter an optical fiber core. This reduction in transmission of optical energy provides optical attenuation that is approximately uniform as a function of wavelength. Alternate configurations include at least one lens, such as GRIN lens, a spherical lens, or an aspherical lens, placed between the optical fiber terminations.

Abstract: A color television camera includes a panchromatic light sensor such as a CCD imager. Light from a scene to be imaged is filtered by an electronically controlled light filter such as an etalon, which is scanned from color to color at the field rate, so that the image for each field is generated by a different color. The periodic spectral line or spectral band response of a single etalon is improved by a cascade of two etalons with different periodicity, which pass only a single spectral line or band. When an RGB color sequence is used, a complete color signal frame is generated in three fields. The imager may be operated at a field rate higher than the standard field rate, such as 90 Hz. for use with conventional 30 Hz. color frame rate, and a memory may be coupled to the output of the imager to store the three-field sequence of signals which occurs during each standard color frame, so that a complete color signal is available during each standard color frame.

Abstract: A Fabry-Perot etalon (310) has a cavity (12) occupied by an electric-field variable index of refraction material (22). The cavity is flanked by a pair of parallel mirrors (14), at least one of which is partially reflecting. At least one of the supporting substrates (18l) has deposited thereon a light polarizing field electrode (316l) which includes a plurality of mutually parallel, spaced apart electrical conductors (392) which define gaps (394). The electrical conductors are mutually interconnected by bus conductors (390), and may be connected by lead conductors (37) to an external voltage source, for generating the desired electric field across the cavity.

Abstract: An optical demultiplexer includes an electrooptic modulator (410) which modulates a beam of light (418) in response to frequency-multiplexed radio-frequency (RF) information signals, to produce diverging beamlets of light (420). The diverging beamlets are separated by a spatial separator arrangement (426), and each beamlet (420), including the information of its RF carrier, is coupled to a separate optical detector (428). The detector (428) can extract amplitude modulation from the signal. In order to reconstruct the RF signal as well as the amplitude modulator, an optical "local oscillator" signal (OLO) is coupled to each detector together with its information signal. Signal loss due to vibration or misalignment is avoided, and heterodyne mixing efficiency is maximized in an embodiment of the invention, by propagating the OLO and information signals through a single-mode optical fiber to the detector.

Abstract: A Fabry-Perot etalon 10 is located in the light path 30 between a light sourcesinks 40 and 44. The etalon is polarization insensitive, and its optical path length and transmission wavelength(s) is controlled by a bias source 60. When light at the desired wavelength is propagating from source 40, the bias is set to establish transmission through the etalon at that wavelength, whereupon the light propagates to the sink 44, and the switch is transmissive. By contrast, if the switch is to be nontransmissive, the bias sets the transmission wavelengths of the etalon on either side of the wavelength produced by source 40, whereupon the light from source 40 is reflected by the etalon, and does not reach sink 44. In a second embodiment, a third sourcesink 48 is coupled in a second light path 330a, for being coupled to the first sourcesink 40 when the etalon is set for reflection, to thereby form a single-pole, double-throw switch.