Abstract: An electromagnetic radiation sensor that exhibits improved performance by virtue of an ability to tune its sensitivity is disclosed. The electromagnetic radiation sensor incorporates thermal actuators that act in opposition to one another, but which have a slight difference in responsivity. A temperature controller is used to tune the sensitivity of the electromagnetic radiation sensor by controlling the temperature of the substrate on which the sensor is formed.

Abstract: A radiation sensor array that exhibits improved fill factor is disclosed. The radiation sensor array incorporates sensors having support arms that are nested in vertical fashion with the support arms of neighboring sensors. This vertically-nested structure enables the radiation-sensing portions of the sensors to be more closely-packed.

Abstract: A high power optical isolator is able to transfer excess heat to a heat sink, reduce the effect of scattered and reflected light, and be coupled to standard thin optical fibers.

Abstract: A chalcogenide glass composition composed of arsenic (As), selenium (Se), sulfur (S), and antimony (Sb) is presented. The composition includes arsenic in the range from 25% to 45% by weight relative to the total weight of the composition, selenium in the range from 40% to 65% by weight relative to the total weight of the composition, sulfur in the range from 2% to 15% by weight relative to the total weight of the composition, and antimony in the range from 0% to 15% by weight relative to the total weight of the composition. The variability of constituents on a weight basis is greater than the related arts, thus facilitating a broader range of design options. The glass composition is preferred to have a thermal expansion coefficient of about 23.6×10?6/° C., a temperature coefficient of refractive index less than about 1×10?6/° C., a glass transition temperature less than 200 degrees Celsius, and/or a glass softening temperature less than 250 degrees Celsius.

Abstract: An optical apparatus and methods for operating on a polarization state of a light beam using a compound tri-state non-reciprocal rotator having two Faraday rotators. A first Faraday rotator rotates the polarization state into one of two partially rotated states at angles +?, ??, where ?=22.5°, and the second Faraday rotates the polarization state from one of the partially rotated states into one of three fully rotated states at angles +2?, 0, ?2?. A polarization selection mechanism guides light in the three fully rotated states differently to enable various devices and different modes of operation. For example, the polarization selection mechanism can generate a tri-state output in the form of two distinct output beams corresponding to two of the three fully rotated states, and an overlapping pair of output beams obtained when the compound tri-state non-reciprocal rotator produces the third of the three fully rotated states.

Abstract: An apparatus and method to operate on a light beam by using a lens that collimates the light beam to a collimated beam with at least one cross-sectional dimension less than a critical dimension of 400 ?m or less over a working range WR. The apparatus has a bulk electro-optic material of small thickness ?, e.g., less than 300 ?m positioned within working range WR and the collimated beam traverses it along its path. The apparatus has a voltage source for applying a low operating or drive voltage Vdrive, e.g. less than 400 V to the bulk electro-optic material for performing an operation on the collimated beam. The lens for collimating the light beam is a free-space collimator such as a graded index (GRIN) lens or preferably a C-lens. The apparatus is a versatile and scalable platform that can be employed in building various electro-optic devices.

Abstract: The present invention provides improved optical switches in which only a spatial beam shifting of a small free space offset is required to direct optical pathways between plural fiber ports. This is achieved by spacing two fibers closely and collimating their beams with one imaging lens for compactness. Advantageously, the inventive switches incorporate beam correcting devices to render the beam propagations parallel, allowing light beams to be efficiently coupled into two fibers that share a single lens with substantially improved stability.

Abstract: The present invention provides improved optical switches in which no mechanical movement is required to direct optical pathways between plural fiber ports. Advantageously, the inventive switches incorporate two-stage polarization rotation to improve isolation depth, as well as temperature and wavelength independence. The inventive switches also incorporate light bending devices to allow two fibers to be coupled to the light beams using a single lens achieving small beam separation for compactness. In the inventive switch, an optical signal is spatially split into two polarized beams by a birefringent element, which passes through a polarization rotation device that comprises waveplates, walk-off elements, and electrically controllable polarization rotators, and recombine into an output fiber, achieving polarization independent operation.

Abstract: The present invention provides an improved optical wavelength switch in which no mechanical movement is required to direct optical pathways between several fiber ports. The inventive three-fiber port device divides incoming optical signals into two subsets of spectra and selectively directs them into two output ports in response to an electrical control signal. In the inventive switch, an optical signal is spatially split into two polarized beams, by a birefringent element, which thereafter pass through a series polarization rotation elements and recombine into output fibers, achieving polarization independent operation. Advantageously, the inventive switch incorporates two-stage polarization rotations to improve isolation depth, as well as temperature and wavelength independence. The invention also incorporates light bending devices to allow two fibers to be coupled to the light beams via a single lens, thereby achieving small beam separation for compactness.