Abstract:
An optical switch for redirecting an optical signal includes a plurality of spaced-apart mirrors disposed in an array for detecting and reflecting one or more optical signals. The mirrors include a reflective member and a sensor. Desirably, the optical signal is detected by the sensor and used for triggering drive means for orientating the mirrors in the array for redirecting the optical signal.
Abstract:
An improved intensity control system for an intensified imaging system allows continuous viewing through an intensified imaging system while protecting saturated areas from the negative effects of overexposure. A micromirror array (MMA) is used in conjunction with associated optics to control the intensity incident on the image intensifier. Control circuitry determines if pixel intensity is above or below the preset threshold level. If above, the corresponding elements of the MMA array will deflect the incident light in that specific area thereby eliminating saturation of the pixels. The rest of the image is maintained for continuous viewing. A continuous feedback loop monitors the intensity levels of pixels and actively controls the incident light using the MMA.
Abstract:
A method for forming a photovoltaic cell which includes forming a nanostructured layer in a semiconductor material having a plurality of pores opening onto a surface, the plurality of pores having a depth greater than about 1 micron and a diameter between about 5 nanometers and about 1,200 nanometers, and disposing an organic charge-transfer material in the pores of the nanostructured layer. A first electrode is attached to the semiconductor material, and a second electrode is attached to the organic charge-transfer material. The semiconductor material has a thickness between about 5 microns and about 700 microns. Desirably, the nanostructured layer has a porosity of less than the porosity corresponding to the percolation threshold, and the organic charge-transfer material extends at least about 100 nm from the surface of the nanostructured layer. The organic charge-transfer material may partially cover the sides of the pores of the nanostructured layer thereby providing a generally cylindrical cavity therein.
Abstract:
A reconfigurable compound diffraction grating is fabricated using microelectomechanical systems (MEMS) technology. The compound grating structure can be viewed as the superposition of two separately configured gratings. A common lower electrode is placed beneath selected beam elements, known as deflectable beams, to achieve the desired grating configuration (i.e. every other, every third, every fifth, etc.) of the beams in the primary grating. These deflectable beams alone comprise a secondary, lower resolution grating structure. The beam elements are linked to a common upper electrode. Voltage applied across the electrodes creates an electrostatic force that pulls the selected beams down toward the underlying electrode. Changing the vertical position of the selected beams with respect to the other stationary beams presents a different ruling spacing distribution to the incoming radiation. By changing this distribution, the diffracted power among individual diffraction orders of the wavelengths is altered. Controlling the diffracted signal in this way allows for specific diffraction passbands to be fixed on a particular detector or a particular area of a detector. Automated adjustments to the rulings can be very rapidly, which would significantly simplify and reduce the time necessary for complete spectral analysis previously achieved by mechanical movement of diffraction gratings.
Abstract:
A silicon-on-insulator (SOI) substrate is anodically bonded to a glass substrate in a MEMS structure with or without electrically bypassing the insulator layer by electrically comprising the silicon layers. The insulator layer serves as an etch stop to create a well-defined, thin silicon membrane for a sensor. A second glass substrate is anodically bonded to the other side of the SOI substrate, and debonding of the existing anodic bond prevented by eliminating any potential drop across the existing bonded surface.
Abstract:
The invention relates to a biosensor comprising living cells that express a chemosensor, or receptor, on their surface. When grown on a microarray comprising electrodes, the cells can be induced, by binding of a ligand to the receptor, to secrete a molecule. This secretion event is detected with millisecond temporal resolution via electrochemical oxidation of the secreted molecule on the electrode which is voltage-clamped slightly above its redox potential. The current so generated is indicative of the amount of the ligand bound to the receptor.
Abstract:
Systems and methods for direct-to-digital holography are described. An apparatus includes a laser; a beamsplitter optically coupled to the laser; a reference beam mirror optically coupled to the beamsplitter; an object optically coupled to the beamsplitter, a focusing lens optically coupled to both the reference beam mirror and the object; and a digital recorder optically coupled to the focusing lens. A reference beam is incident upon the reference beam mirror at a non-normal angle, and the reference beam and an object beam are focused by the focusing lens at a focal plane of the digital recorder to form an image. The systems and methods provide advantages in that computer assisted holographic measurements can be made.
Abstract:
The present invention provides a method of isolating motile cells from an animal tissue, the method comprising implanting in the animal tissue a cell trap comprising a chamber with an inlet for ingress of motile cells and a porous matrix located in the chamber comprising a chemotactic factor, for a time sufficient for the motile cells to migrate into the cell trap; removing the implanted cell trap; and retrieving the motile cells from the cell trap.
Abstract:
The present invention provides an improvement in a wavelength division multiplexer and/or a dense wavelength division multiplexer (WDM/DWDM) by incorporating an electronically reconfigurable diffraction grating. The introduction of the electronically reconfigurable diffraction grating, which is typically fabricated using MEMS (microelectromechanical systems) technology, improves the compact design, durability, and dynamic functionality of the WDM/DWDM system.
Abstract:
The invention relates to a biosensor comprising living cells that express a chemosensor, or receptor, on their surface. When grown on a microarray comprising electrodes, the cells can be induced, by binding of a ligand to the receptor, to secrete a molecule. This secretion event is detected with millisecond temporal resolution via electrochemical oxidation of the secreted molecule on the electrode which is voltage-clamped slightly above its redox potential. The current so generated is indicative of the amount of the ligand bound to the receptor.