Non-toxic flakes for authentication of pharmaceutical articles
Granted: June 23, 2009
Patent Number:
7550197
In one embodiment of the present invention, non-toxic inorganic flakes are used for identification and anticounterfeit protection of pharmaceutical articles, such as pills, tablets and capsules, having a core of a biologically active material and/or a biologically inert material. Non-toxic inorganic authentication flakes, either optically variable flakes or taggant flakes having one or more symbols and/or a selected shape are disposed on the surface or inside of the pharmaceutical…
Temperature compensated lasers
Granted: June 2, 2009
Patent Number:
7542493
A novel approach for providing temperature compensation for semiconductor lasers is disclosed. This approach utilizes reflectivity characteristics in the at least one of the mirrors of the semiconductor laser to provide temperature compensation to the device.
Humidity tolerant electro-optic device
Granted: May 5, 2009
Patent Number:
7529433
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.…
Pluggable small form factor transceivers
Granted: May 5, 2009
Patent Number:
7529521
The present invention provides a transceiver housing comprising: an opening at a proximal end thereof for receiving a optical receptacle; an electrical contact for engaging the optical receptacle and retaining the optical receptacle in the housing body; and a first side and a second side, each of the first side and the second side including mountings for mounting a printed wire assembly within the housing. In a preferred embodiment, the transceiver housing of the present invention has a…
Continually variable demetallization of metallized films and similar objects
Granted: April 28, 2009
Patent Number:
7525705
A method of generating a variable demetallized pattern in a holographic web and a security device using such method. A holographic microstructure pattern is imparted to an oligomer disposed on a surface of a substrate. A metal layer, such as aluminum, is deposited to the holographic microstructure pattern of the substrate and then covered with a variable resist pattern. The variable demetallized pattern in the holographic web is then generated by removing the metal layer not covered by…
Asymmetric directional coupler having a reduced drive voltage
Granted: April 21, 2009
Patent Number:
7522784
The invention relates to an electro-optic directional coupler suitable for use as a variable optical attenuator at reduced voltages compared to those known in the prior art. The present invention has found that by careful selection of an asymmetric directional coupler geometry, the transfer function of the device can be shifted so that it has an operating point between maximum and minimum transmission. Signal electrodes driven in push pull configuration advantageously use this operating…
Method and apparatus for orienting magnetic flakes
Granted: April 14, 2009
Patent Number:
7517578
Apparatus and related methods align magnetic flakes in a carrier, such as an ink vehicle or a paint vehicle to create optically variable images in a high-speed, linear printing operation. Images can provide security features on high-value documents, such as bank notes. Magnetic flakes in the ink are aligned using magnets in a linear printing operation. Selected orientation of the magnetic pigment flakes can achieve a variety of illusive optical effects that are useful for decorative or…
Power stabilization of semiconductor laser harmonic frequency conversion modules
Granted: April 14, 2009
Patent Number:
7518786
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…
Phase matched optical grating
Granted: April 7, 2009
Patent Number:
7515791
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…
Polarization maintaining fiber pigtail assembly
Granted: March 31, 2009
Patent Number:
7512306
The invention provides a fiber pigtail assembly wherein a polarization maintaining fiber is soldered directly to a mounting pad without a sleeve or a ferrule therebetween. A portion of the polarization maintaining fiber near a fiber end is embedded in a vertical slow axis orientation within an asymmetrical solder ball having a flat portion for adhering to the mounting pad. The vertical slow axis orientation of the polarization maintaining fiber within the solder ball enhances power…
Wafer scale method of manufacturing optical waveguide devices and the waveguide devices made thereby
Granted: March 31, 2009
Patent Number:
7512303
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…
Compact optical sub-assembly with ceramic package
Granted: January 13, 2009
Patent Number:
7476040
The present invention relates to an optical sub-assembly, i.e. a receiver optical subassembly or a transmitter optical sub-assembly, for use in an optical transceiver device. The optical sub-assembly according to the present invention includes a hermetic ceramic package with a multi-layer ceramic structure providing a unique RF signal and ground structure providing a controlled signal impedance to achieve high signal transmission quality.
Variable Optical Attenuator
Granted: January 13, 2009
Patent Number:
7477827
A variable optical attenuator is disclosed, which attenuates a beam of light while preserving its polarization substantially independent of wavelength. The beam of light is attenuated by a filter patterned with a grating of blocking stripes with serrated edges, which partially block and partially transmit the beam of light, respectively. The serrated edges provide for low polarization dependent loss. Along a length of the filter, a mark to space ratio of blocking stripe and aperture…
Flexible control and status architecture for optical modules
Granted: December 16, 2008
Patent Number:
7466922
The invention relates to optoelectronic modules for generating and/or receiving optical signals for use in fiber-optic communication systems, such as optical transponders or transceivers, having a reconfigurable control and status (C&S) interface with a host device. The optoelectronic module includes an electrical multi-pin host connector having a plurality of pins for communicating a plurality of digital C&S signals between the host and the module, functional hardware responsive…
Low loss grating for high efficiency wavelength stabilized high power lasers
Granted: November 25, 2008
Patent Number:
7457341
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.
Pulse shaping circuit
Granted: November 18, 2008
Patent Number:
7453306
The invention relates to a pulse shaping circuit for shaping electrical pulses driving an optical transmitter, e.g. a lased diode or an LED, and for providing electrical pulses having independently height and width-adjustable peaking at the edges thereof. The pulse shaping circuit of the present invention includes a high-pass RC filter with a differential output for providing transient electrical pulses from an input differential pulse, an adjustable voltage offset generating circuit, a…
Micro-electro-mechanical-system two dimensional mirror with articulated suspension structures for high fill factor arrays
Granted: October 28, 2008
Patent Number:
7443569
The invention provides a micro-electro-mechanical-system (MEMS) mirror device, comprising: a mirror having a 2-dimensional rotational T-shaped hinge at a first end, and having a flexible connection at a second end opposite the first end. The invention also provides a MEMS mirror device, comprising: a mirror having a 2-dimensional rotational T-shaped hinge at a first end; and a vertical actuator connected to the 2-dimensional T-shaped hinge through a rigid connection. The invention also…
Planar lightwave circuit based wavelength selective switch
Granted: October 21, 2008
Patent Number:
7440650
The present invention extends the concept of a standard array waveguide grating (AWG), which focuses each wavelength component launched via an input AWG to a Rowland circle inside a planar lightwave chip (PLC) where discrete waveguides are located, to one which focuses each wavelength component outside of the PLC chip along a straight line. An array of MEMS mirrors or other redirecting elements is positioned at the focus location for independently redirecting each of the wavelength…
Articulated MEMs structures
Granted: October 7, 2008
Patent Number:
7432629
The present invention relates to an articulated micro-electro-mechanical (MEMS) device, which is constructed in such a way as to enable several of the devices to be closely packed together, i.e. high fill factor, for redirecting specific wavelengths of light from a dispersed optical signal to different output ports. The articulated MEMS device includes multiple pivotally connected sections that are pivotable about two perpendicular axes for limiting the amount of dynamic cross-talk as…
Tunable optical add/drop multiplexer
Granted: October 7, 2008
Patent Number:
7433557
The tunable add/drop multiplexer including a tiltable mirror, a fixed thin film filter, and first and second retro-reflector elements for redirecting express channels back out an input/output port and for redirecting drop channels back out an add/drop port, respectively.
