Patent application number | Description | Published |
20090071708 | INTEGRATED ELECTRICAL CROSS-TALK WALLS FOR ELECTROSTATIC MEMS - To reduce cross-talk between adjacent hot electrodes, the present invention provides a ground plane, which extends beneath each side of a MEMS mirror platform covering opposite edges of a hot electrode along each side thereof. The ground plane includes an overhang section extending between the mirror platform and the hot electrode forming a first gap between the hot electrode and the overhang section, and a second gap between the overhang section and the mirror platform. The method of the present invention enables highly accurate construction using lithographic patterning and deep reactive ion etching (DRIE). | 03-19-2009 |
20090190202 | MEMS MICROMIRROR DEVICES WITH ANTI-REFLECTIVE STRUCTURES - Diffractive patterns are disposed on a MEMS substrate in the gaps between the MEMS micromirrors to reduce backreflection of light leaking through the gaps and reflected by the MEMS substrate. The diffractive patterns are silicon surface-relief diffraction gratings or silicon oxide gratings on silicon substrate. Sub-wavelength gratings are used to suppress higher orders of diffraction; 50% duty cycle surface relief gratings on a substrate having index of refraction close to 3 are used to suppress both reflected and transmitted zero orders of diffraction simultaneously. The gratings have lines running parallel or at a slight angle to the gaps, to prevent the diffracted light from re-entering the gaps. | 07-30-2009 |
20090268295 | SURFACE-RELIEF DIFFRACTION GRATING - A bilayer transmission diffraction grating having antireflection lines having rectangular cross-section over grating lines having trapezoidal cross-section is described. The process-dependent grating line profile is accounted for by characterizing the grating line profile and performing electromagnetic wave diffraction simulations, whereby a grating duty cycle is selected that results in an improvement of overall diffraction efficiency and/or reducing polarization dependent loss of a diffraction grating having the characterized grating line profile. Grooves in the substrate between the grating lines further improve diffraction efficiency and reduce polarization dependent loss. The entire grating line profile, including the antireflection line, the grating line, and the groove in the substrate between the grating lines, can be defined using a single etch mask, which reduces process and equipment related manufacturing costs. | 10-29-2009 |
20130176621 | DIFFRACTIVE MEMS DEVICE - A diffractive MEMS device has an in-plane binary reflective diffraction pattern formed in an outer surface of a tiltable platform. The binary reflective diffraction pattern includes rectangular or trapezoidal ridges and valleys, or grooves, of a same depth. The binary reflective diffractive pattern has a high diffraction efficiency even though the surfaces of the “grooves” or “ridges” are not perpendicular to the incoming optical beam. The diffractive pattern is supported by a pair of torsional hinges and is tiltable by an electrostatic actuator. The electrostatic actuator can include at least one side electrode for linearization of dependence of tilt angle on the voltage applied to the actuator. | 07-11-2013 |
20130194654 | BIAXIAL MEMS MIRROR WITH HIDDEN HINGE AND STAGGERED ELECTRODES - A multi-layer hidden hinge and actuator design for high fill factor biaxial MEMS mirror array for wavelength selective switches (WSS) including a coarsely aligned orthogonal vertical comb drive and/or parallel plate actuator. Each micro-mirror in the MEMS linear piano micro-mirror array comprises a reflective body/mirror layer, a ground/hinge layer and a hot electrode/substrate layer. To increase the amount of surface area available for the hot and ground electrodes, the dimensions of the ground/hinge layer are extended longitudinally or laterally across the air gap between reflective layers to beneath the adjacent reflective layer. Ideally, diffraction patterns are formed on the surface of the ground/hinge layer to prevent stray light from reflecting back into the system. | 08-01-2013 |
20140055695 | VARIABLE OPTICAL RETARDER - A sub-wavelength grating is placed inside a liquid crystal variable optical retarder to reduce polarization dependence of the optical retardation generated by the variable optical retarder. A small thickness of the sub-wavelength grating, as compared to a conventional waveplate, reduces the driving voltage penalty due to the in-cell placement of the sub-wavelength grating. | 02-27-2014 |
20150234221 | REFLECTIVE LC DEVICES INCLUDING THIN FILM METAL GRATING - A sub-wavelength thin-film metal grating is placed inside a liquid crystal variable optical retarder at a selected distance from a reflective electrode to form a reflective half wave plate, thereby reducing polarization dependence of the optical retardation generated by the variable optical retarder. The approach enables to form within the device the reflective half wave plate that is suitably thin without modifying the reflective electrode of the device. | 08-20-2015 |
20150276998 | REFLECTIVE DIFFRACTION GRATING AND FABRICATION METHOD - A reflective diffraction grating and a fabrication method are provided. The reflective diffraction grating includes a substrate, a UV-absorbing layer, a grating layer having a binary surface-relief pattern formed therein, and a conforming reflective layer. Advantageously, the UV-absorbing layer absorbs light at a UV recording wavelength to minimize reflection thereof by the substrate during holographic patterning at the UV recording wavelength. | 10-01-2015 |