Patent ID: 9103784
Filing Date: 2015-08-11
Classification: G01B,G01N,G01Q,G02B

Abstract:
1. A method of determining Z-axis position of a fluorescent nanoscale object with nanometer precision and accuracy relative to a reference surface defined by X- and Y-axes comprising: a. generating a standing wave excitation pattern between a reflecting surface and the reference surface along the Z-axis with a focused excitation light source selected to excite fluorescence from the object and a reflection of the excitation source along the same Z-axis; b. placing the object in the standing wave to generate an excited fluorescence having an intensity that oscillates proportionally to the standing wave; c. recording the oscillating intensity and phase of the excited fluorescence while varying distance of the reflecting surface from the object along the Z-axis; and d. deriving position of the object along the Z-axis by comparing the phase of the recorded excited fluorescence to a reference.