US 12,189,104 B2
Methods and apparatus for optimised interferometric scattering microscopy
Josiah Kane, Oxford (GB); Max Felix Hantke, Oxford (GB); and Lewis Carney, Oxford (GB)
Assigned to REFEYN LTD, Oxford (GB)
Appl. No. 17/912,260
Filed by REFEYN LTD, Oxford (GB)
PCT Filed Mar. 15, 2021, PCT No. PCT/GB2021/050639
§ 371(c)(1), (2) Date Sep. 16, 2022,
PCT Pub. No. WO2021/186154, PCT Pub. Date Sep. 23, 2021.
Claims priority of application No. 2003946 (GB), filed on Mar. 18, 2020.
Prior Publication US 2023/0185067 A1, Jun. 15, 2023
Int. Cl. G02B 21/00 (2006.01)
CPC G02B 21/0028 (2013.01) [G02B 21/0032 (2013.01); G02B 21/0056 (2013.01); G02B 21/0084 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method of imaging a sample by interferometric scattering microscopy, the method comprising:
illuminating a sample with at least one light source, the sample being held at a sample location comprising a reflective surface, such that a reflected signal is formed; the reflected signal comprising light from the light source and light scattered by the sample;
detecting an output light over a first time window for a first frame N1;
detecting an output light over a second time window for a second frame N2;
calculating a ratiometric signal R which is: a ratio of N1 and N2, minus 1;
estimating a ratiometric motion signature S=(Sx, Sy) from the native camera frames N1 and N2, which is a ratiometric image which would be measured from an invariant sample moving along x and y for a given motion vector m=(mx, my);
estimating m as a most consistent vector such that R is approximated using S and m;
calculating a corrected ratiometric contrast image R* from R, S and m;
wherein the corrected ratiometric contrast image frame R* is calculated as
R*=R−(mxSx+mySy).