Intel Corporation

Other

Lockheed Missiles & Space Company, Inc.

Transparent Networks, Inc.

Cheng-Chung Huang

Dmitry Vasily Bakin

Steven Saeed Nasiri

Janusz Bryzek

Alex Harwit

Randall Brian Sprague

Zbigniew Sufleta

James Higgins Smith

David Skurnik

Eric Charles Abbott

Daryl Ray Hawkins

Tao Chang

A method of controllably attenuating a beam of light coupled into a port includes directing the beam of light against a mirror, and controlling an orientation of the mirror such that a predetermined fraction of the beam of light is coupled into the port. The predetermined fraction is less than a maximum fraction corresponding to optimal coupling of the beam of light into the port. The method may be implemented with a variable optical attenuator including a first port, a second port, a mirror located to direct light output by the first port to the second port, and a controller coupled to the mirror to align it such that the predetermined fraction of light is coupled into the second port. The method may also be implemented with an optical switch.

Variable optical attenuator

In the beam path of an Optical Cross Connect between the front face of a fiber block and a moveable mirror array are placed a telecentric lens and multi-surface optical element. The lens is placed adjacent the front face with a front focal plane coinciding with the front face. The substantially parallel beam path axes between the front face and the telecentric lens are converted by the lens into dispersing directions towards the optical element. Discrete optical surfaces of the optical element redirect the dispersing beam paths in a fashion such that the beam paths coincide in the following with corresponding moveable mirrors of a mirror array. Pitches of arrayed fiber ends and of the optical surfaces as well as the moveable mirrors are independently selectable. The telecentric lens simultaneously focuses the signal beams with improved beam separation and reduced signal loss.

Optical cross-connect switch with telecentric lens and multi-surface optical element

Methods of calibrating and operating optical switches as well as optical switches in which the orientations of mirrors are measured and controlled using control light beams and position sensing detectors are described. The present invention may provide high resolution control of a plurality of mirrors in an optical switch and thus allow the optical switch to cross-connect a large number of input and output ports with a low insertion loss.

Optical system for calibration and control of an optical fiber switch

An optical fiber switch in accordance with an embodiment of the present invention includes a first plurality of ports, a second plurality of ports, a first plurality of mirrors disposed on a first surface, and a second plurality of mirrors disposed on a second surface. Each one of the first plurality of mirrors is individually controllable to direct light output from a corresponding one of the first plurality of ports to any one of the second plurality of mirrors. Each one of the second plurality of mirrors is individually controllable to direct to a corresponding one of the second plurality of ports light incident on it from any one of the first plurality of mirrors. Advantageously, optical fiber switches in accordance with embodiments of the present invention may couple more than a thousand input ports to more than a thousand output ports with an insertion loss of less than about 3 decibels.

Optical configuration for optical fiber switch

An optical switching fabric enables an optical signal entering the device on any one of multiple input ports to be directed to any one of multiple output ports. The present optical switching fabrics include sensing and monitoring devices that permit precise initial calibration and continuous switch connection status monitoring and control. Light entering the switching fabric on an input port is reflected by one of a first set of individually controllable mirrors to one of a second set of individually controllable mirrors and then to a corresponding output port. The switching fabrics include control lasers and position sensing devices which provide output signals corresponding to the orientations of the mirrors. In addition, a subset of the input ports and output ports can be attached to monitor light sources and detectors for recalibration and control. Further, sensors for detecting the intensity of input signals, of signals that have been reflected by a mirror in the first set and by a mirror in the second set, and of signals backscattered from the output ports may be included.

System architecture of optical switching fabric

A control system for controlling individual mirrors in a MEMS-based optical switching fabric is presented. The control system includes a position sensitive detector positioned to receive a control beam reflected from individual mirrors of a first mirror array. In some embodiments, the control beam can be time-multiplexed with a calibration beam. The position of the control beam corrected in response to the position of the calibration beam can be compared with a position calculated on the port assignment of the individual mirrors in order to provide feedback to a feed-back based control system for the individual mirrors.

Feedback control system for a MEMS based optical switching fabric

An adjustable, head mountable stereoscopic viewer having a head band to mount the viewer to the user. A tilt bracket is pivotally joined on one end to the head band and at a pivot point on an opposite end to an optical assembly for adjustment of the assembly position to obtain maximum field of view. The optical assembly includes first (left) and second (right) mirror assemblies that receive and direct left and right stereo images from an image source, such as a poster, a TV image, etc., to the corresponding left and right eyes of the user. The left and right stereo images are displayed horizontally at the source, the right image preferably displayed above the left image. Each mirror assembly has two mirrors and an aperture, and functions in a similar manner to a periscope. Adjustment for a range of image sizes and distances is accomplished with a mirror adjustment, provided to vary the tilt of the mirror of one of the assemblies to adjust the overlap of the images. The optical assembly is adjustable about the pivot point to eliminate the unwanted upper (right) image from the left eye. An adjustable shutter plate is provided to restrict the optical opening to the right assembly for eliminating the unwanted lower (left) image from the right eye.

Adjustable head mountable stereoscopic viewer

Two optical beams of different frequencies are focussed as concentric spots, one spot being larger than the other, on a reflective surface whose roughness is to be measured. The smaller spot has a maximum dimension that is smaller than any significant deviation of the profile of the surface from spatial uniformity, and the larger spot has a minimum dimension that is larger than any significant deviation of the surface profile from spatial uniformity. The two beams are reflected from the surface along a common path with a phase difference that is measured by a heterodyne interferometric technique. The phase difference measurement is indicative of the roughness of the surface, and is substantially insensitive to vibration of the surface.

Optical heterodyne roughness measurement system

A sensor for measuring angular deviations of a radiation beam relative to a reference plane. The sensor comprises a shearing interferometer block formed of a beamsplitter cube having a first reflecting device on one face of the cube for forming a first exit beam and a second reflecting device on the opposite face of the cube for forming a second exit beam. The first device can be a corner cube or a flat block mirror. The second device can be a right angle prism for one dimensional measurements and a 90.degree. pyramid prism for two-dimensional measurements. A photo-detector unit is adjacent to and spaced from the beam splitter cube and has a number of detector members across the path of travel of the wavefronts of the exit beams. The detector members provide output signals which can be used to calculate the angular deviation of the incoming beam from a normal to the reference plane. The optical path difference between the two arms of the interferometer block are equal substantially to odd multiples of one-fourth the wavelength of the incoming radiation. The sensor is accurate to better than 0.001 arc seconds of angular measurements for a photodetector unit whose maximum transverse dimension is 2.5 cm.

Angular alignment sensor

The disclosed heterodyne measurement apparatus utilizes a single coherent light source to simultaneously measure the location of a number of points on a surface. The coherent light is split into two parts by a Bragg Cell. One part, after being spatially split into a plurality of beams by a second Bragg Cell, fed to a plurality of reflectors on the surface, and recombined by the second Bragg Cell, is heterodyned with the second part. The heterodyned signal is fed to a photodetector and further processed to produce a signal representative to the distance to the points of interest on the surface.

Growing community of inventors

Sunnyvale, CA, United States of America

Cheng-Chung Huang