Variable Optical Attenuator With Wavelength Dependent Loss Compensation
Granted: February 8, 2007
Application Number:
20070031104
The invention relates to compensating for the wavelength dependent loss (WDL) in a variable optical attenuator (VOA) system by using a chromatic dispersion wedge, which is inserted between the mirror and the lens. Different wavelength components, e.g. shorter blue and longer red wavelengths, are redirected at different angles by the chromatic dispersion wedge and now arrive at the output fiber at different positions. Thus the smaller mode field diameter (MFD) or mode spot size of the…
Apparatus and method for characterizing pulsed optical signals
Granted: December 21, 2006
Application Number:
20060285117
The coherent interference effect between two beam is used with one light beam delayed by a controllably variable time delay with respect to another analogous beam to obtain a convolutional profile of the oscillatory component of the interference amplitude as a function of the time delay, having a peak value representing the performance clearance between a zero-bit and a one-bit. The convolutional profile is represented by a diamond diagram (DD) of the interference amplitude, within the…
Covert Security Coating
Granted: December 21, 2006
Application Number:
20060285184
A multilayer thin film filter is disclosed an organic dielectric layer serving as a spacer layer in a Fabry-Perot structure. The dielectric has embossed regions of varying thicknesses wherein the thickness within a region is substantially uniform. Each different region of a different thickness produces a different color (shift). The size of one of the embossed adjacent regions is such that the color of said one region is uniform and cannot be seen by a human eye as different in color…
Phase Matched Optical Grating
Granted: December 21, 2006
Application Number:
20060285795
The invention relates to phase matched optical gratings for performing signal multiplexing and demultiplexing in optical communications networks. In prior art gratings there is a phase linearity error between the grating line and the outputs on the focal line, comparing the center output to the surrounding outputs. This corresponds to a relative phase difference between each output which limits the passband. In the case of the AWG this degradation comes primarily from field aberrations…
Producing two distinct flake products using a single substrate
Granted: November 30, 2006
Application Number:
20060267241
A novel method is disclosed wherein a reflective coated organic substrate is releasably coated with a thin film coating having one or more layers for forming flakes once removed from the reflective substrate. The reflective substrate is conveniently used to make glitter after the flake material is removed.
Tilted C-Plate Retarder Compensator And Display Systems Incorporating The Same
Granted: November 30, 2006
Application Number:
20060268207
A C-plate compensator is disclosed for compensating the residual A-plate and C-plate retardance of a reflective liquid crystal on silicon (LCoS) display or a transmissive liquid crystal (LC) display in a projection display system. The C-plate incorporates a form-birefringent coating, whose retardance magnitude can be adjusted by tilting with respect to the display panel (X-Y) plane. The tilted plate is rotated about the Z-axis by a prescribed amount from the slow axis of the display…
Injection seeding of frequency-converted Q-switched laser
Granted: November 30, 2006
Application Number:
20060268950
A non-linearly frequency-converted Q-switched laser is “injection seeded” with short pulses from another laser, called a seed laser. Radiation produced by the Q-switched laser is frequency converted in a non-linear process. The injection seeding can enhance peak power and frequency conversion efficiency while reducing damage to a non-linear medium used to frequency convert radiation generated by the Q-switched laser.
Alignable Diffractive Pigment Flakes And Method And Apparatus For Alignment And Images Formed Therefrom
Granted: November 23, 2006
Application Number:
20060263539
Diffractive pigment flakes are selectively aligned to form an image. In one embodiment, flakes having a magnetic layer are shaped to facilitate alignment in a magnetic field. In another embodiment, the flakes include a magnetically discontinuous layer. In a particular embodiment, deposition of nickel on a diffraction grating pattern produces magnetic needles along the grating pattern that allow magnetic alignment of the resulting diffractive pigment flakes. Color scans of test samples of…
Electro-optic waveguide device capable of suppressing bias point DC drift and thermal bias point shift
Granted: October 19, 2006
Application Number:
20060233494
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…
High dynamic range integrated receiver
Granted: October 19, 2006
Application Number:
20060233498
A high dynamic range integrated (HDRI) receiver includes a variable optical attenuator (VOA) for attenuating an incoming optical signal before the optical signal is directed to a photo-detector for conversion into an electrical signal. An optical block receives the optical signal from an optical fiber and includes optics for directing the optical signal to the VOA, and for directing the optical signal from the VOA to the photo-detector.
High chroma optically variable color-shifting glitter
Granted: October 12, 2006
Application Number:
20060228553
Opaque glitter particles that are uniform in size and shape are disclosed that have an optically variable color with a change in angle of incident light. The glitter particles have an organic substrate and an optical interference structure on one or both sides of the organic substrate. The optical interference design can be a Fabry-Perot structure or can be an optically variable ink.
Stabilization Of Actively Q-Switched Lasers
Granted: October 5, 2006
Application Number:
20060222023
The invention discloses an actively Q-switched laser with an intracavity nonlinear coupler in which a stable optical frequency converted output is generated. A Gain Fluctuation Insensitivity Condition is defined and described for several examples. The nonlinear coupler with a coupling level which satisfies this Condition permits stable laser operation with minimal interaction between pulses, even when the pulses are clipped by the Q-switch. Thus, the output pulse duration and repetition…
Engraved optically variable image device
Granted: September 14, 2006
Application Number:
20060204724
A method and image made by the method is disclosed wherein non-spherical magnetically alignable optical pigment flakes in transparent carrier are applied to a substrate and are aligned by applying a magnetic field to the substrate. The pigment flakes align along magnetic field lines and a tool for impressing or scribing the flakes is applied to a sub-region of the substrate to realign or remove flakes from a desired region. For example a scribing tool can be used to scribe a signature or…
Anti-moisture and soil-repellent coatings
Granted: September 14, 2006
Application Number:
20060204766
An anti-moisture and soil-repellent coating and a method of preparing the same includes a fluorinated alkyl ether polymer having a functionalized silane that is applied to a non-oxide surface. Advantageously, the instant invention provides a durable anti-moisture and soil-repellant coating for relatively inert surfaces, such as MgF2, without the need for a primer layer.
DYNAMIC APPEARANCE-CHANGING OPTICAL DEVICES (DACOD) PRINTED IN A SHAPED MAGNETIC FIELD INCLUDING PRINTABLE FRESNEL STRUCTURES
Granted: September 7, 2006
Application Number:
20060198998
A printed image is disclosed wherein the image may be in the form of an array of magnetically aligned platelets or flakes that may by uniform in shape and size and wherein the flakes are arranged in a particularly manner to form optically illusive images useful as security devices, or useful in beam steering applications. In one embodiment of this invention printed array is disclosed a plurality of concentric rings of magnetically aligned platelets disposed upon a substrate in the form…
Two-step method of coating an article for security printing
Granted: August 31, 2006
Application Number:
20060194040
A two-step method of making of a security printed image is disclosed and includes coating of the surface of a substrate with a predetermined image shape with an ink containing flaked magnetic pigment in a predetermined concentration, exposing a wet printed image to a magnetic field to align magnetic particles in a predetermined manner, allowing the ink to cure, and coating the substrate with a second printed image on the top of the first image. The second printed image with the same or…
Low loss grating for high efficiency wavelength stabilized high power lasers
Granted: August 24, 2006
Application Number:
20060187995
A low optical loss and high efficiency grating is placed within a broad-area high-power laser diode or single spatial mode laser diode to narrow the spectral width and stabilize the emission wavelength. Several embodiments of grating configurations are presented, together with the measured results of a reduction to practice of a particular embodiment.
Passively Q-switched laser with adjustable pulse repetition rate
Granted: August 10, 2006
Application Number:
20060176913
A method is disclosed for varying a pulse repetition rate of a passively q-switched laser while maintaining other characteristics of the laser radiation. The laser is optically pumped with a sequence of pump pulses which includes alterations between non-zero power levels and is characterized by two adjustable parameters. By simultaneously changing the adjustable parameters, the pulse repetition rate of the laser can be changed while maintaining the laser pulse energy, divergence of the…
Optical performance monitor
Granted: July 13, 2006
Application Number:
20060153498
An optical performance monitor for accurate monitoring of the OSNR of a WDM optical signal is provided wherein a demultiplexing arrayed waveguide grating (AWG) having a plurality of Vernier input ports is disposed between an optical switch and a photodiode array coupled to the output ports of the AWG. In operation, the optical switch sequentially provides the input optical signal into each of the Vernier ports, and signals detected by photodiodes are stored in a memory unit. The…
Two-panel color management system
Granted: June 8, 2006
Application Number:
20060119797
The invention provides a two-panel color management system for projection display applications, wherein color sequencing is accomplished using achromatic beam switching and static color separation. In a preferred embodiment, a liquid-crystal polarization switch alternates a polarization of an input light beam between two orthogonal states. A polarization beam splitter directs the beam comprising three primary color components alternately along a first and second paths, wherein first and…