Humidity Tolerant Electro-Optic Device
Granted: July 17, 2008
Application Number:
20080170821
The invention relates to an electro-optic modulator structure containing an additional set of bias electrodes buried within the device for applying bias to set the operating point. Thus the RF electrodes used to modulate incoming optical signals can be operated with zero DC bias, reducing electrode corrosion by galvanic and other effects that can be present in non-hermetic packages. The bias electrodes are at least partially separated from the substrate with a buffer layer, which in one…
Printed Magnetic Ink Overt Security Image
Granted: July 17, 2008
Application Number:
20080171144
A security image and method of forming said image is disclosed wherein a substrate having an image or indicia thereon is coated with a dilute solution of pigment flakes in an ink or paint. The flakes are subsequently aligned in a magnetic field and are fixed after the field is applied. Most or all of the flakes in a region are aligned so as to be partially upstanding wherein their faces are essentially parallel. Coating the image with flakes yields a latent image which can be clearly…
Humidity Tolerant Electro-Optic Device
Granted: July 17, 2008
Application Number:
20080170818
The invention relates to an electro-optic modulator structure containing an additional set of bias electrodes buried within the device for applying bias to set the operating point. Thus the RF electrodes used to modulate incoming optical signals can be operated with zero DC bias, reducing electrode corrosion by electro-migration and other effects that can be present in non-hermetic packages. The bias electrodes include an upper split portion and an optically transparent lower portion.…
Circuit And Method For Lessening Noise In A Laser System Having A Frequency Converting Element
Granted: June 19, 2008
Application Number:
20080144678
A method and circuit is disclosed for a laser system wherein the power of the laser signal is kept at a constant near optimum value and a portion of an frequency doubled output signal is monitored and detected so that noise within the frequency doubled output signal can be minimized. A feedback signal is used to dither the temperature of a frequency doubled crystal so as to minimize the noise in the frequency doubled output signal.
Small Optical Package Having Multiple Optically Aligned Soldered Elements Therein
Granted: June 19, 2008
Application Number:
20080144997
A thermally stable small optical package is disclosed housing optically aligned elements forming an optical component. The elements are all directly soldered to a base member or directly soldered to a supporting member soldered to a common base member. The sealed container has a supporting base member of stainless steel and a first optical fiber mount is directly soldered to the supporting base. A first optical fiber is directly soldered to the upper end of the first optical fiber mount.…
Harmonic Frequency Conversion Module
Granted: June 12, 2008
Application Number:
20080137693
A harmonic frequency conversion module is disclosed including a polarization maintaining (PM) fiber optical link for providing an output stabilized from power fluctuation by the inclusion of one or more polarizers in the PM fiber optical link. Removing polarization distortions removes noise which has a significant negative effect on the output of harmonic frequency conversion elements. It has been found that the noise in frequency converted light has additional components, caused by mode…
Power Stabilization Of Semiconductor Laser Harmonic Frequency Conversion Modules
Granted: May 29, 2008
Application Number:
20080124023
The invention relates to a fiber laser and harmonic frequency conversion module incorporating a 90 degree Polarization Maintaining (PM) fiber fusion splice therebetween for providing temperature insensitive power stabilization. The present invention has found that incorporating at least one 90 degree splice of the transmission axes of the PM fiber, coupling a fast axis to a slow axis, to create substantially equal optical path lengths of the two transmission axes of the fiber coupling…
Kit For Providing An Image On A Substrate
Granted: May 29, 2008
Application Number:
20080124491
A kit for producing optically variable images is disclosed wherein the kit includes a special effect pigment having particles that are magnetically alignable, a magnet for aligning the particles and a scribing tool for personalizing an image. Alternatively or in addition the kit can include e-field responsive flakes in a carrier vehicle and an electric field source for aligning said flakes. A stylus may be included for moving or changing the alignment of a portion of the flakes that have…
Semiconductor Laser Diode With Narrow Lateral Beam Divergence
Granted: May 15, 2008
Application Number:
20080112451
The invention relates to high power broad-area semiconductor lasers incorporating a structure that provides both gain guiding and index guiding. The lateral width of the index guiding region is greater than the lateral width of the gain guiding region by at least 20 micron. This results in a high power broad-area semiconductor laser which has reduced lateral divergence of the output beam.
Provision of Frames Or Borders Around Pigment Flakes For Covert Security Applications
Granted: May 8, 2008
Application Number:
20080107856
Opaque flakes, such as pigment or bright flakes used in paints and inks, have a selected shape and/or other indicia to provide a covert security feature to an object. Shaped opaque covert flakes are not readily detectable by causal observation, but in some embodiments are easily seen at 50× magnification. In manufacturing the flakes a sheet of embossed frames are provided having embossed symbols or indicia within. Upon removing a coating from the embossed sheet the coating material…
Bias-Control for Optical Mach-Zehnder Modulators with Voltage-Induced Optical Absorption
Granted: April 24, 2008
Application Number:
20080094123
A bias-control circuit that provides operating point control for a Mach-Zehnder modulator experiencing optical absorption at their interferometric arms. The bias control circuit generates compensation signals that are used to counter the thermally induced index shifts as a result of absorption. In addition, an operating point with desirable transmitter characteristics can also be arbitrarily chosen by over-compensating or under-compensating thermal effects.
Integrated Termination For EO Modulator With RF Signal Monitoring Functionality
Granted: April 24, 2008
Application Number:
20080095542
The invention relates to RF termination for reducing electrical signal reflections at the end of transmission line electrodes on an electro-optical (EO) optical modulator. The disclosed termination incorporates a RF tap which permits the monitoring of the RF power and reflection conditions at the EO modulator. The integrated termination/tap can also be integrated with detection circuitry, such as RF diodes and passive components, giving improved performance, lower cost manufacturability…
Article With Micro Indicia Security Enhancement
Granted: April 17, 2008
Application Number:
20080088895
The invention provides an article having an enhanced security feature provided by association of first indicia imaged directly on a substrate or an additional layer supported thereby, and second indicia imaged on flakes within or supported by the substrate. At least the second indicia are discernible only with magnification.
Wafer Scale Method Of Manufacturing Optical Waveguide Devices And The Waveguide Devices Made Thereby
Granted: April 10, 2008
Application Number:
20080085089
The invention relates to a wafer scale process for the manufacture of optical waveguide devices, and particularly for the manufacture of ridge waveguide devices, and the improved waveguides made thereby. The present invention has found a process for achieving sub-micron control of an optical waveguiding layer thickness by providing a dimensionally stable wafer assembly into which adhesive can be introduced without altering the planar relationship between a carrier wafer and an optically…
Semiconductor Laser Diode With Advanced Window Structure
Granted: March 20, 2008
Application Number:
20080069165
The invention relates to a semiconductor laser diode structure with increased catastrophic optical damage (COD) power limit, featuring three sections, sometimes called windows, at the output facet of the diode. These include an optically transparent section, a current blocking section and a partially current blocking section.
Electro-Optic Device
Granted: March 20, 2008
Application Number:
20080069491
The invention relates to an electro-optic modulator structure containing an additional set of bias electrodes buried within the device for applying bias to set the operating point. Thus the RF electrodes used to modulate incoming optical signals can be operated with zero DC bias, reducing electrode corrosion by electro-migration, galvanic, and other effects that can be present in non-hermetic packages. The RF electrodes are supported by a first surface of the electro-optic substrate,…
Security image coated with a single coating having visually distinct regions
Granted: March 20, 2008
Application Number:
20080069979
A security image is disclosed which is formed from flakes having a first color with flakes having a second different color mixed within a carrier uniformly. The flakes having the second color are magnetically orientable and the flakes having the first color are non-magnetic and do not align or orient in a magnetic field. By exposing at least a single coated region to a magnetic field that is substantially orthogonal to the substrate upon which the coating of flakes is coated, a visible…
Printed Article With Special Effect Coating
Granted: March 6, 2008
Application Number:
20080054623
A printed article is disclosed having a light transmissive substrate having a reverse printed region on a surface thereof in the form of a plurality of very closely spaced printed lines or regions. The printed regions and spaces therebetween are subsequently flood coated with special effect ink such as optically variable ink wherein the ink particle size is on average greater than the gap between reverse printed regions. The image is viewed from the non-printed side of the substrate and…
Passive Depolarizer
Granted: February 28, 2008
Application Number:
20080049321
The present invention relates to a passive depolarizer for use in an optical system having an image plane. The passive depolarizer includes a patterned half wave plate incorporating a monolithic layer of birefringent material. The monolithic layer includes a plurality of regions having fast axes with at least four different orientations. Accordingly, a polarized beam of light launched into the patterned half wave plate is substantially depolarized at the image plane.
Optical Pick-Up Unit
Granted: February 28, 2008
Application Number:
20080049584
An optical pick-up including a fold mirror having an achromatic quarter-wave plate coating is provided. To allow the thin film coating to efficiently provide the quarter-wave retardation, the optical pick-up is configured such that the polarization of light incident on the fold mirror is at a predetermined angle. According to one embodiment, the predetermined angle is provided by rotating the light sources. According to another embodiment, the predetermined angle is provided by rotating…
