The United States of America As Represented by the National Security Agency

The United States of America As Represented by the National Security

The United States of America As Represented by the Director of the

The United States of America As Represented by the Director of the National Security Agency

Duane Anthony Satorius

Timothy E Dimmick

Paul John Boudreaux

A photonic integrated chip having low insertion loss and facilitating alignment of the optical fiber with an optical device, preferably a waveguide or optical detector. The photonic integrated chip includes an optical fiber having a substantially spherical lens attached to one end. The device includes an etched via that receives the spherical lens attached to the optical fiber. An optical device is aligned with the via opposite the spherical lens such that light transmitted through the spherical lens is transmitted to the optical device. An anti-reflection coating is preferably applied on the end of the optical device abutting the via and the surface of the spherical lens to reduce scattering and insertion loss during transmission of data from the spherical lens to the optical device. Index matching fluid is alternatively disposed between the spherical lens and the via for this same purpose.

Photonic integrated circuit and method of fabricating same

Device whereby one or more bands of optical wavelengths may be selected for further transmission. All light within the optical bandwidth of operation is first coupled from the core mode of an optical fiber to a specific cladding mode by a chirped broadband cladding mode coupler. These cladding mode lightwaves then enter a narrow-band core mode coupler whereby selected optical bands of wavelengths, tuned by the tension on the optical fiber, are re-coupled back into the core of the optical fiber. The chirped broadband cladding mode coupler is isolated from the narrow-band core mode coupler by an acoustic absorber to limit the acoustic interaction between them.

Tension-tuned acousto-optic bandpass filter

A device whereby one or more bands of optical wavelengths may be selected for further transmission. All light within the optical bandwidth of operation is first coupled from the core mode of an optical fiber to a specific cladding mode by a chirped broadband cladding mode coupler. These cladding mode lightwaves then enter a narrow-band core mode coupler whereby selected optical bands of wavelengths are re-coupled back into the core of the optical fiber. The chirped broadband cladding mode coupler is isolated from the narrow-band core mode coupler by an acoustic absorber to limit the acoustic interaction between them.

Chirped fiber acousto-optic bandpass filter

The acousto-optic bandpass filter is a device whereby one or more bands of optical wavelengths may be selected for further transmission. In this device, all light within the optical bandwidth of operation is first coupled from the core mode of a optical fiber to a specific cladding mode by a long-period photo-induced grating. These cladding mode lightwaves then enter an acousto-optic interaction region where selected RF frequencies of flexure waves, induced by an acoustic wave amplifier, re-couple selected bands of wavelengths back into the core mode. The interaction region is isolated from the broadband coupler by an acoustic absorber to limit acoustic interaction to the interaction region.

Acousto-optic bandpass filter

A device for compensating for dispersion that includes a single-mode optical fiber consisting of a core, and a cladding, where the fiber has five section, a first section of a user-definable length; a second section of a user-definable length that is tapered at a user-definable rate to a user-definable diameter; a third section of a user-definable length and user-definable cutoff wavelength that is of a diameter equal to that which the second section was tapered; a fourth section of a length equal to the length of the second section, where the fourth section is tapered at the same, but opposite, rate of taper as the second section to a diameter equal to the diameter of the first section; a fifth section of a length equal to the length of the first section, and where the fiber has a user-definable cutoff wavelength. In a second embodiment, two spatial-mode converters are included with the fiber. In a third embodiment, a core-block is induced in the fiber. In other embodiments, a polarizer and a polarization rotator are included in the previous embodiments.

Device for dispersion compensation using tapered single-mode optical fiber

The present invention is a tunable optic fiber bandpass filter using flexural acoustic waves that includes an optic fiber; a first silica horn; a first acoustic transducer; a first signal generator; a first acoustic absorber; a core blocker; a second acoustic absorber; a second silica horn; a second acoustic transducer; and a second signal generator. The method of the present invention is receiving an optic signal in a core of an optic fiber; inducing a first flexural acoustic wave in the optic fiber where there is no buffer coating; absorbing the first flexural acoustic wave after it has traveled a distance down the optic fiber; causing user-definable wavelengths of the optic signal to exit the core and enter the cladding of the optic fiber; blocking wavelengths of the optic signal that remain in the core of the optic fiber; inducing a second flexural acoustic wave in the optic fiber where there is no buffer coating; absorbing the second flexural acoustic wave after it has traveled a distance down the optic fiber; and causing user-definable wavelengths of the optic signal to exit the cladding and enter the core of the optic fiber. One signal generator may be used to induce both flexural acoustic waves. In an alternate embodiment, one absorber may be used.

Tunable optic fiber bandpass filter using flexural acoustic waves

The present invention stores and retrieves digital information by altering the phase transmission characteristics of a multiple layer phase recording by modulating the carrier frequency and the carrier frequency angle. These layers are organized into several regions, called page areas, which contain an array of juxtaposed encoded digital information data. Each page area may have several pages of digital information; each recorded with a different carrier frequency and carrier angle. The data layers are stacked together and aligned such that the page areas and encoded digital information on them are also aligned with each other into books. When one of these books is selectively illuminated by a controllable light source, a lenslet aligned with that book projects the transformed images of the data pages within that book, through a shutter array, and a reimaging lens onto a photosensor detector array. By selectively illuminating individual books and selectively opening the transform plane shutter to pass a single desired transformed page of digital data, any desired page of any desired book in the stack of data layers can be imaged onto the photosensor detector array. Pages of data can thus be randomly accessed and all data on that page can be read in parallel at speeds limited only by the access speeds of the illumination source, spatial frequency plane shutter array, and photosensor detector array.

Photorefractive read-only optical memory apparatus using phase,

The present invention is a wide field of view electro-optic detector and locator of coherent light of unknown wavelength that includes a collecting optic that collimates incoming optical radiation, a common-path electro-optic polarization interferometer placed at an exit pupil plane, an imaging optic, a detector array placed one focal length away from said imaging optic, an image processor that processes the incoming signal in a manner that is independent of the phase of the modulation signal, and an output device. The preferred collecting optic includes a first lens, a field lens, and a collimating lens. The preferred interferometer includes a first polarizer, a liquid crystal variable phase modulator, a fixed phase retarder, and a second polarizer.

Growing community of inventors

Fulton, MD, United States of America

Duane Anthony Satorius