US 2017/0363415 A1 · Multichannel Optical Receivers

Abstract

Methods and apparatus are presented for multichannel optical coherence tomography. Light from a wavelength tuneable or steppable optical source is separated into one or more sample beams and one or more reference beams, and the one or more sample beams directed onto a sample to form one or more interaction regions. A plurality of returning probe beams are collected and mixed with the one or more reference beams to form an interference pattern comprising a plurality of interferograms having at least two distinct carrier frequencies. The multichannel optical apparatus can be provided with polarisation discrimination by mixing the returning probe beams with two orthogonally polarised reference beams to form one or more interference patterns each comprising a plurality of interferograms having at least two distinct carrier frequencies. In preferred embodiments each interferogram has a distinct carrier frequency, which may be provided by ensuring that each returning probe beam has a distinct propagation angle with respect to a reference beam. Also presented is a means of generating a plurality of beamlets from a sample beam using a nonreciprocal optical splitter configured to split a beam propagating in a forwards direction into a plurality of beamlets, and to transmit without splitting a beam propagating in the reverse direction.

Claims45

Dependent claims

A multichannel optical coherence tomography apparatus comprising a wavelength tuneable or steppable optical source and an interferometer, said interferometer being configured to:

separate light from said optical source into one or more sample beams and one or more reference beams;
direct said one or more sample beams onto a sample to form one or more interaction regions within which said light interacts with said sample;
collect a plurality of returning probe beams emanating from said one or more interaction regions;
mix said plurality of returning probe beams with said one or more reference beams to form an interference pattern comprising a plurality of interferograms having a set of carrier frequencies, wherein said set of carrier frequencies comprises at least two distinct carrier frequencies;
and
detect said interference pattern with a photodetector array, such that a temporal sequence of interference patterns can be detected with said photodetector array as said optical source is stepped or tuned in wavelength.

3 more elements

Dependencies are inferred from the claim text.

Multichannel Optical Receivers

Life of this patent

Multichannel Optical Receivers

Life of this patent

Abstract

Claims45