Flake for covert security applications
Granted: August 21, 2007
Patent Number:
7258915
Covert flakes having one or more symbols and/or a selected shape are used in a composition, such as ink or paint, to provide a covert security feature to an object. In some embodiments the composition includes base pigment, and the covert flakes are covert pigment flakes that match the visual characteristics of the base pigment. In another embodiment, clear covert flakes are mixed in the carrier with base pigment. In another embodiment, clear covert flakes are mixed in a varnish base to…
Diode-pumped laser
Granted: August 21, 2007
Patent Number:
7260133
A diode-pumped laser with a direct edge coupling of a pump beam is provided. The laser includes a microchip laser cavity optically pumped by a laser diode emitting an astigmatic pump beam having a substantially elliptical beam cross-section at an output laser diode facet. The microchip laser cavity is disposed at a substantial distance exceeding 0.001? from the laser diode pump where the astigmatic pump beam has a greatly reduced ellipticity, providing high laser output efficiency…
Magnetic planarization of pigment flakes
Granted: August 21, 2007
Patent Number:
7258900
A magnetic field is applied to planarize magnetic pigment flakes relative to a surface. Pigment flakes, such as optically variable pigment flakes, are used in a variety of paints, inks, extrusions, powder coatings, and other forms for decorative and security applications. In many applications pigment flakes tend to align parallel to each other and to the surface to which they are applied. If the pigment flakes include a suitable magnetic structure, a magnetic field can be applied to…
Folding converging light into a lightpipe
Granted: August 7, 2007
Patent Number:
7252399
The present invention relates to a folded front end unit used in a light engine of a projection display device. The front end unit comprises a light source for generating a beam of light, and a lightpipe for providing spatial uniformity to the beam of light. Polarization-dependent front end units include polarization beam splitters for separating the light into orthogonally polarized sub-beams, and a polarization rotating element, e.g. a waveplate, for rotating the polarization of one of…
Polarization state frequency multiplexing
Granted: August 7, 2007
Patent Number:
7253906
A method for the rapid measurement of polarization dependent properties of an optical device under test uses a novel technique to generate light in four different polarization states in which each state is individually sensed at a different interference frequency. The device for executing this method includes a Mach-Zehnder interferometer (M-Z) having a reference arm and a signal arm. In the signal arm, a device called a “polarization state frequency multiplexer” (PSFM) splits the…
Dispersion compensating filters
Granted: August 7, 2007
Patent Number:
7254294
A filter device provides for the modification of the group delay of an optical signal without attenuation of adjacent optical signals in a WDM optical communication systems. The filters devices may be combined and used in various methods to modify the GD and dispersion. The filters are configured and designed to provide various controllable and different amounts of GD as well as dispersion at different over a range of wavelengths.
Metal alloy elements in micromachined devices
Granted: July 17, 2007
Patent Number:
7244367
A micromechanical device is provided, which includes at least one flexible member formed from an alloy, where the alloy is made up of one or more noble metals and one or more alloying elements, wherein each of the alloying elements has an equilibrium solid solubility in the noble metal, and wherein the one or more alloying elements are present in an amount that does not result in precipitates. A method for making a micromechanical device includes depositing an alloy on a substrate to…
Opaque flake for covert security applications
Granted: July 10, 2007
Patent Number:
7241489
Opaque flakes, such as pigment or bright flake used in paints and inks, have a selected shape and/or other indicia to provide a covert security feature to an object. In some embodiments the composition includes base pigment, and the opaque covert flakes match the visual characteristics of the base pigment. In another embodiment, opaque covert flakes are mixed in the carrier with base pigment at a concentration sufficient to avoid changing the appearance of the composition. In another…
All-dielectric optically variable pigments
Granted: July 3, 2007
Patent Number:
7238424
The light transmitted and reflected by all-dielectric optically variable pigments varies according to viewing angle. The color travel of an all-dielectric optically variable pigment depends on amplitude changes and wavelength shifts in reflectance peaks of the pigment. The width and center wavelength of reflectance peaks can be controlled by selecting the ratio of thicknesses between high-index and low-index layers in a thin film stack. Reflectance peaks can regenerate or become…
Reconfigurable optical add-drop module, system and method
Granted: June 26, 2007
Patent Number:
7236660
An apparatus, system, and method for all-optical wavelength add-drop switching are provided. A number of optical ports, including at least one input port and at least one output port, are each optically coupled to a respective dispersive element. When a multichannel optical signal is input through an input port, an optical beam of each channel emerges from the dispersive element at an angle depending upon its wavelength. The beams emerging from the dispersive element pass through a bulk…
Titanium-containing interference pigments and foils with color shifting properties
Granted: June 26, 2007
Patent Number:
7235300
Interference pigment flakes and foils are provided which have color shifting properties. The pigment flakes can have a symmetrical coating structure on opposing sides of a reflector layer, can have an asymmetrical coating structure with all of the layers on one side of the reflector layer, or can be formed with encapsulating coatings around a core reflector layer. The coating structure of the flakes and foils includes a reflector layer, a dielectric layer on the reflector layer, and a…
Electro-optic waveguide device capable of suppressing bias point DC drift and thermal bias point shift
Granted: June 12, 2007
Patent Number:
7231101
The present invention discloses an electro-optic waveguide device such as a modulator. The device has an electro-optic substrate having optical waveguides within the substrate at or near an upper surface. A buffer layer is formed on the top surface of the electro-optic substrate. A novel block layer is formed on the buffer layer surface, which can suppress or lessen an unwanted occurrence of chemical reactions at or near the surface of the buffer layer. A charge bleed off layer is formed…
Test system for remotely testing switches within a telecommunications network
Granted: June 12, 2007
Patent Number:
7231187
A system for centrally and remotely testing cellular and conventional telecommunications network wherein a controller located at a remote location provides instructions to Remote Call Processor (RCP) to thereby prompt the RCPs to establish a communication link from the RCP through a switch to a destination device whereby audio from said destination device is communicated, by way of the RCP, to the controller in order to verify that the network properly routed and billed the call. The…
Integration of electronic data storage into a telecommunications component
Granted: May 29, 2007
Patent Number:
7223964
A storage information system is disclosed for keeping archival information on the individual active optoelectronic components that are used in telecommunication equipment. The system involves enclosing a nonvolatile memory chip inside the hermetic package of the active optoelectronic component. A memory chip is used to keep the relevant information about the active optoelectronic component such as serial number, part number and specifications. Sensors can also be included inside the…
Optically variable security devices
Granted: May 29, 2007
Patent Number:
7224528
A security article includes a light transmissive substrate having a first surface and an opposing second surface, with the first surface having an optical interference pattern such as a holographic image pattern or an optical diffraction pattern thereon. A color shifting optical coating is formed on the substrate such as on the interference pattern or on the opposing second surface of the substrate, with the optical coating providing an observable color shift as the angle of incident…
Adaptive distortion compensation in optical fiber communication networks
Granted: May 29, 2007
Patent Number:
7224911
An apparatus for adaptively receiving, compensating, and transmitting data in optical fiber communication networks are provided. A receiver according to this invention includes at least one optical device for compensating distortion in a channel of an optical signal, at least one photodetector circuit for converting the optical signal into an electrical signal, at least one electronic device for further compensating the distortion in the electronic signal, a clock and data recovery…
Optical communications system with fiber break detection in the presence of Raman amplification
Granted: May 15, 2007
Patent Number:
7218442
An optical communications system initiates automatic power reduction by selecting a portion of a Raman optical pumping signal from optical signals propagating on an optical fiber span. A signal related to a magnitude of the selected portion of the Raman optical pumping signal is generated. Power of at least one of the optical data signals and the optical pumping signals propagating in the optical fiber span is reduced in response to the generated signal.
Methods for determining the performance, status, and advanced failure of optical communication channels
Granted: May 8, 2007
Patent Number:
7215883
Methods of determining the performance and the advanced failure of an optical communication channel. Performance of an optical communication channel may be determined by receiving light signals, generating a measure of an average received optical power in the received light signals and monitoring changes in the measure of the average received optical power. Advanced failure of an optical communication channel may be determined by transmitting a light signal at one end of the optical…
Integrated driving, receiving, controlling, and monitoring for optical transceivers
Granted: May 8, 2007
Patent Number:
7215891
An optical transceiver includes a single integrated circuit chip to integrate the drive, receive, control, and monitoring functions of the optical transceiver. The single chip may further have an advance replacement algorithm and monitoring algorithm for the opto-electronic devices of the optical transmitter and receiver to generate flags and/or an advance replacement indication. Methods, apparatus, and systems are disclosed.
Wavelength stabilized laser
Granted: May 1, 2007
Patent Number:
7212554
A high power light source having an array, bundle or separate plurality of laser diodes coupled to a same number of multimode waveguides to collect beams of light emitted from the of laser diodes is provided. An optical combiner receives the beams of light and combines the beams of light into a single forward propagating beam of light so that substantially all optical radiation within each beam of light overlaps the optical radiation each other beam to form the single beam. A reflective…
