High-resolution light microscope using coherent light reflected from a target to modulate the power output from a laser

US5260562A · kind A · utility

Assignee

• The Regents of the University of California · US

Inventors

• Alan J. Bearden · Berkeley, US
• Michael P. O'Neill · Richmond, US

Key dates

• Filing date: Mar 24, 1991
• Grant date: Nov 9, 1993
• Expiry date: Mar 24, 2011

Classification

• Technology area (CPC G): Physics
• CPC primary: G01B11/303
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An optical microscope for examining surface features of a target surface, at a resolution, in one dimension, in the picometer-to-nanometer range. The microscope includes a laser for use in producing a coherent output light beam, a lens for focusing the output beam onto a target, and a photodetector for measuring the power output of the beam. The focused beam is moved relative to the target surface in a defined position-dependent pattern, with a portion of the light reflected from the target surface being reflected back into the laser. Changes in the measured power of the laser are converted to position-dependent surface displacements, in the direction of the output beam.