Optical measuring device

Patent metadata

Field	Value
Publication number	US-2016356708-A1
Application number	US-201514861606-A
Country	US
Kind code	A1
Filing date	Sep 22, 2015
Priority date	Jun 3, 2015
Publication date	Dec 8, 2016
Grant date	—

Abstract

An optical measuring device for measuring a measurement region, the optical device comprising a photonic chip with an interferometer defined on said chip, said interferometer comprising first and second waveguides on said photonic chip and an interference region, wherein the first and second waveguides carry signals from the interference region to the sample region and back to the interference region, the device further comprising a phase adjusting unit configured to vary a phase difference between the signals in the first and second waveguides reflected by the measurement region.

First claim

1 . An optical measuring device for measuring a measurement region, the optical device comprising a photonic chip with an interferometer defined on said chip, said interferometer comprising first and second waveguides on said photonic chip and an interference region, wherein the first and second waveguides carry signals from the Interference region to the sample region and back to the interference region, the device further comprising a phase adjusting unit configured to vary a phase difference between the signals in the first and second waveguides reflected by the measurement region.

2 . An optical measuring device according to claim 1 , wherein the measurement region comprises a first region and a second region, the signal in the first waveguide being reflected by the first region and the signal in the second waveguide being reflected by the second region, wherein the phase adjusting unit is configured to adjust the phase such that there is maximum interference at the interference region when the reflectance properties of the first region and the second region match.

3 . An optical measuring device according to claim 1 , further comprising an input waveguide and an output waveguide defined on said photonic chip, the input waveguide being adapted to pass a light signal to said interference region such that the light signal propagates along the first and second waveguides after the Interference region, the output waveguide being configured to carry a signal from the interference region after it has been reflected by the measurement region, the amount of signal transferred to the output waveguide from the input waveguide being controlled by the phase adjusting unit.

4 . An optical measuring device according to claim 3 , wherein the measurement region comprises a first region and a second region, the signal in the first waveguide being reflected by the first region and the signal in the second waveguide being reflected by the second region, wherein the phase adjusting unit is configured to adjust the phase such that the signal transferred to the output waveguide is minimised when the reflectance properties of the first region and the second region match.

5 . An optical measuring device according to claim 3 , wherein a detector is provided to receive the output from the output waveguide.

6 . An optical measuring device according to claim 1 , further comprising a variable loss element provided in at least one of the first and second waveguide, wherein the variable loss element is configured to vary the amplitude of the signal in said at least one of the first and second waveguide.

7 . An optical measuring device according to claim 1 , wherein the measurement region comprises a sample having a surface, and wherein the surface of the sample is orthogonal to the direction of travel of the signal in the first and second waveguides.

8 . An optical measuring device according to claim 1 , wherein the first and second waveguides are single mode waveguides.

9 . An optical measuring device according to claim 3 , wherein a light source is attached to the input waveguide.

10 . An optical measuring device according to claim 1 , wherein the phase adjusting element on said photonic chip is a heating element configured to heat part of the first and/or second waveguide.

11 . An optical measuring device according to claim 3 , further comprising a controller adapted to control the phase adjusting controller to minimise the output signal in the output waveguide and determine the phase adjustment applied for minimising the signal in the output waveguide.

12 . An optical measuring device according to claim 1 , the measurement region comprising a first region and a second region, wherein the first region and the second region transmit radiation at the frequency of the input optical signal, the device further comprising a mirror provided such that an optical signal transmitted through the first region is reflected from the mirror back into the first waveguide and a mirror provided such that an optical signal transmitted through the second region is reflected back from the mirror into the second waveguide.

13 . An optical measuring device according to claim 12 , wherein the first region is configured to contain a fluid and the second region is configured to contain a fluid, the first and second regions being configured such that the physical path length of the optical signal through the fluids contained in the first and second regions is the same to allow variations in the refractive index to be determined between the fluid in the first region and the fluid in the second region.

14 . An optical measuring device according to claim 1 , further comprising a movement stage configured such that the measurement region is moveable with respect to the first and second waveguides.

15 . An optical measuring device according to claim 3 , configured to measure the displacement of an object in said measurement region, further comprising a measurement stage configured to position the object such that the displacement of the object in the measurement region causes a variation in the path length between the signals following the first waveguide and the second waveguide, the device further comprising a detector adapted to measure the signal in the output waveguide over time.

16 . An optical measuring device according to claim 3 , configured to measure an optically activated quantum emitter, the optical measuring device further comprising a stage for supporting said quantum emitter in the measurement region such that said quantum emitter is coupled to one of the first or second waveguide, the phase adjusting unit configured to vary a phase difference between the signals in the first and second waveguide to minimise the signal transferred from the input waveguide to the output waveguide.

17 . An optical measuring device according to claim 16 , wherein the light signal provided from the input waveguide is at an energy that can excite the quantum emitter.

18 . An optical measuring device according to claim 17 , wherein the output waveguide is coupled to a further photonic circuit, an interferometer.

19 . An optical measuring system comprising a first optical measuring device and a second optical measuring device, the first optical measuring device comprising the optical measuring device of claim 17 and the second optical measuring device comprising the optical measuring device of claim 17 , wherein the output guide of the first optical measuring device and the output guide of the second optical measuring device are coupled at a coupler.

20 . A method of performing an optical measurement of a measurement region, the method comprising providing an optical measuring device comprising a photonic chip with an interferometer defined on said chip, said interferometer comprising first and second single mode waveguides on said photonic chip and an interference region,
the method comprising passing signals from the interference region via said first and second waveguides to the measurement region and back to the interference region via the same first and second waveguides and varying a phase difference between the signals in the first and second single waveguides reflected by the measurement region.

Assignees

• Toshiba Kk

Inventors

• Bennett Anthony John
• Ellis David Julian Peter
• Shields Andrew James
• Meany Thomas David

Classifications

• G02B2006/12121

  Laser · CPC title

• G02F1/0147

  based on thermo-optic effects (G02F1/132 takes precedence) · CPC title

• G01N2201/08

  Optical fibres; light guides · CPC title

• G02B6/125

  Bends, branchings or intersections · CPC title

• G01N21/45 Primary

  using interferometric methods; using Schlieren methods · CPC title