Microscopic transmittance spectroscopy using a supercontinuum laser source

Abstract

A supercontinuum laser source emitted from an optical fiber is suitable for developing microscopic transmittance spectroscopy. The microscopic supercontinuum transmittance spectrum can be taken with a fiber probe or a reflective objective. The reflective objective is only suitable for measuring a very thin sample of a thickness less than 1 µm. Therefore, while measuring a relatively thick sample, the fiber probe is the better choice because it effectively simplifies the system without lowering the resolution. The spatial resolution of the microscopic transmittance spectrum as a function of the optical wavelength, measurement distance, and sample thickness is quantitatively evaluated for a fiber probe.