High sensitivity phase microscopy imaging

Patent metadata

Field	Value
Publication number	US-12038569-B2
Application number	US-201917273255-A
Country	US
Kind code	B2
Filing date	Sep 4, 2019
Priority date	Sep 5, 2018
Publication date	Jul 16, 2024
Grant date	Jul 16, 2024

Abstract

A device for phase microscopy is disclosed that comprises a spatial light modulator and a connecting means adapted to fix the spatial light modulator onto a phase microscope. The phase microscope comprises a light path comprising at least a sample area, a light device for lighting said sample area, and an imaging device for capturing a phase image of said sample area. The phase image is a 2D matrix of pixels. The spatial light modulator is positioned in the light path in a conjugated plane of the sample area. The device also comprises a command of the spatial light modulator connected to the imaging device and adapted to measure the phase shift of a plurality of pixels of the phase image and to command the spatial light modulator in order to subtract the measured phase shifts.

First claim

The invention claimed is:

1. Device for phase microscopy comprising:
a spatial light modulator;
one or more elements adapted to fix the spatial light modulator onto a phase microscope, said phase microscope comprising a light path comprising at least a sample area, a first device configured to light said sample area and a second device configured to capture a phase image of said sample area, said phase image being a 2D matrix of pixels, so that the spatial light modulator is positioned in the light path in a conjugated plane of the sample area; and
at least one processor of the spatial light modulator connected to the second device and adapted to:
measure the phase shift of a plurality of pixels of the phase image and
command the spatial light modulator in order to subtract the measured phase shift from light rays associated with the plurality of pixels.

2. Device according to claim 1 , wherein:
the phase image is generated by an optical field E written as the sum of a plane reference wave E R and a scattered wave E S :E=|E|e iψ(x,y) =|E R |+|E S (x, y)|e iϕ(x,y) , where:
Ψ(x,y) is the phase of the optical field E,
|E R | is the field amplitude of the plane reference wave E R ,
ϕ(x,y) is the phase of the scattered wave E S ,
|E S | is the field amplitude of the scattered wave E S , which yields to an intensity of the phase image I(x, y)=|E S (x, y)| 2 +|E R | 2 +2|E S (x, y)||E R |cos(ϕ(x, y)−α), where α is chosen to be equal to ±π/2,
the spatial light modulator subtracts the measured phase-shift from the light rays associated with the plurality of pixels,
the at least one processor of the spatial light modulator is further adapted to command a repetition of capturing the phase image of said sample area, measuring the phase shift of the plurality of pixels of the phase image, and controlling the spatial light modulator in order to subtract the measured phase shifts, recursively, and until the absolute value of the difference ψ(x, y)−ψ meas (x, y) is less than π/8, where Ψ meas (x,y) is the measured phase shifts.

3. Device according to claim 1 , characterized in that the spatial light modulator is positioned between the first device and the sample area.

4. Device according to claim 1 , characterized in that the spatial light modulator is positioned between the sample area and the second device.

5. Device according to claim 1 wherein the at least one processor is a part of a computer, and wherein the computer further comprises:
at least one memory including computer program code, the at least one memory and computer program code configured to cause the at least one processor to measure the phase shift of a plurality of pixels of the phase image and control the spatial light modulator in order to subtract the measured phase shifts.

6. Method for obtaining a phase image of a sample by using a phase microscope according to claim 1 , characterized in that the method comprises:
a step of capturing a first phase image of the sample with the spatial light modulator in a pass-through mode;
a step of measuring a phase shift of at least one pixel of the first phase image;
a step of controlling the spatial light modulator so that it subtracts the measured phase shift from the light rays associated with the plurality of pixels.

7. Method according to claim 6 , characterized in that the step of capturing a first image is replaced by a step of acquiring a plurality of images that allow for an estimate of the phase shifts induced by the sample area.

8. Method according to claim 6 , characterized in that the steps are repeated recursively.

9. A non-transitory computer readable medium encoding a machine-executable program of instructions to perform a method according to claim 6 .

Assignees

• Univ Sorbonne
• Centre Nat Rech Scient
• Ecole Normale Superieure De Paris

Inventors

• Gigan Sylvain
• Juffmann Thomas
• De Los Ríos Sommer Andrés

Classifications

• G02B21/365

  Control or image processing arrangements for digital or video microscopes (G02B21/361, G02B21/362 take precedence) · CPC title

• G02B21/14 Primary

  affording illumination for phase-contrast observation · CPC title