Optical microscope with nanometer longitudinal resolution based on a Linnik interferometer

TL;DR

This paper presents a Linnik interferometer-based optical microscope achieving nanometer longitudinal resolution, utilizing phase-shifting and polarized single-shot methods for precise, vibration-insensitive measurements suitable for various applications.

Contribution

The paper introduces a novel optical microscope design with nanometer resolution using a Linnik interferometer and compares two effective interference measurement techniques.

Findings

Achieves 10 nm Z resolution with phase-shifting method

Vibration-insensitive observation with polarized single-shot method

Low-cost, simple design suitable for diverse applications

Abstract

A microscope based on the Linnik interferometer was designed, built, and tested. Two methods were used for interference pattern measurement: phase-shifting and polarized single-shot methods. The former uses a low coherence light emitting diode as a light source, providing 10 nm resolution in the Z direction and diffraction-limited resolution in the X and Y directions. The second method is insensitive to vibrations and enables observation of moving objects. The simplicity and low cost of this instrument make it valuable for a variety of applications.