FOCUSING METHODS AND OPTICAL SYSTEMS AND ASSEMBLIES USING THE SAME

摘要

A method for controlling a focus of an optical system. The method includes providing a pair of incident light beams to a conjugate lens. The incident light beams are directed by the lens to converge toward a focal region. The method also includes reflecting the incident light beams with an object positioned proximate to the focal region. The reflected light beams return to and propagate through the lens. The method also includes determining relative separate measured between the reflected light beams and determining a degree-of-focus of the optical system with respect to the sample based upon the relative separation.