A method and apparatus are provided for determining a property of a fluid downhole by using a tunable optical grating to collect a fluid's spectrum over a wavelength region of interest. A property of the fluid is estimated from spectra that are obtained from light that has interacted with the fluid and then been reflected off of the tunable optical grating onto a photodetector.

Method and apparatus for estimating a property of a fluid downhole

Systems for extended depth frequency domain optical coherence tomography are provided including a detection system configured to sample spectral elements at substantially equal frequency intervals, wherein a spectral width associated with the sampled spectral elements is not greater than one-half of the frequency interval. Related methods are also provided herein.

Systems for Extended Depth Frequency Domain Optical Coherence Tomography (FDOCT) and Related Methods

Optical coherence tomography systems for imaging a whole eye are provided including a sample arm including focal optics that are configured to rapidly switch between at least two scanning modes in less than about 1.0 second.

Systems for Comprehensive Fourier Domain Optical Coherence Tomography (FDOCT) and Related Methods

We review techniques to characterize optical data with very high fidelity using the principle of optical sampling based on four-wave mixing in a highly nonlinear fiber. This approach results in sub-ps time resolution without artifacts in the impulse response and also excellent sensitivity allowing statistical analysis. In particular we describe implementations aimed at differentially phase encoded data (such as DQPSK) with all-optical balanced detection, formats requiring the complete signal field recovery (such as QAM) with phase-sensitive sampling, and signals requiring real-time recovery with all-optical real-time sampling. The all-optical approach to characterize optical waveform is shown to be very attractive and practical way to capture the details of various kinds of data and is, in principle, also scalable to extremely high baud rates.

All-Optical Waveform Sampling in High-Speed Optical Communication Systems Using Advanced Modulation Formats

A color management system is described herein. Various embodiments of a method described herein can include receiving source color content that is associated with a source device, and transforming the source color content into destination color content for rendering on one or more destination devices. Various embodiments of an apparatus described herein can include a color infrastructure transformation engine that further includes a sequential transform component, which is adapted to receive source color content and to create a transform to facilitate mapping the source color content to destination color content. The color infrastructure transformation engine can also include a transform optimization component that is adapted to receive the transform and to create an optimized transform table based on the transform, and a transform execution component that is adapted to receive the optimized transform table and to generate the destination color content based thereon.

Multimedia color management system

An optical spectrum analyzer has a deflection section for changing an incidence angle of measured light on a diffraction grating, a plurality of light detection sections for detecting the dispersed measured light and outputting an electric signal responsive to the light strength, and a signal processing section for finding an optical spectrum of the measured light based on the electric signal from the light detection sections. The light detection sections are arranged along the wavelength dispersion direction of the diffraction grating and output electric signals independently of each other.

Optical spectrum analyzer

http://ieeexplore.ieee.org/iel5/5757121/5757122/05758675.pdf

Monitoring of DPSK/DQPSK Signals using 1-Bit Delayed Self-Homodyne Detection with Optical Phase Diversity

We describe a technique for measuring the phase-distribution of optical signals without requiring an optical reference using delayed self-homodyne detection. The intended phase distributions of 40-Gbit/s RZ-DPSK and -DQPSK were obtained experimentally.

Measurement of Phase-Distribution of Phase-Modulated Optical Signals using Delayed Self-Homodyne Detection

B-10-50 Measurement of Phase-Distribution of Phase-Modulated Optical Signals using Delayed Self-Homodyne Detection

We propose a new technique to measure an optical spectrum instantaneously by using an acousto-optic deflector. We successfully observed a wavelength-changed optical spectrum at 1-msec intervals with 100-?sec scanning time and 80-pm wavelength resolution.

Hiroshi Ohta

Papers

Optical spectrum analyzer

Monitoring of DPSK/DQPSK Signals using 1-Bit Delayed Self-Homodyne Detection with Optical Phase Diversity

Measurement of Phase-Distribution of Phase-Modulated Optical Signals using Delayed Self-Homodyne Detection

B-10-50 Measurement of Phase-Distribution of Phase-Modulated Optical Signals using Delayed Self-Homodyne Detection

High-Speed Scanning Optical Spectrum Measurement with Acousto-Optic Deflector