Imaging and measurement of the surface profile of an object with high resolution has become essential in both of
biological research and industry application. Many samples under investigation such as cultured cells are usually
immersed in liquid. Although the techniques such as scanning electron microscope and atomic force microscope can
provide imaging or measurement of the surface profile with nanometer resolution, it is difficult for them to image an
immersed object with their typical types. Recently, we have proposed and demonstrated a new technique based on
composite interferometer which can perform imaging and measurement of the surface profile of an object with accuracy
in the axial direction within 5 nm through a self-phase-compensation mechanism. In this research, an optical system
based on the concept of combination of optical coherence microscopy (OCM) and composite interferometer was built for
imaging of biological tissue immersed in water with axial accuracy at nanometer scale. In the system, a Ti:sapphire laser
with center wavelength at 800 nm and spectral width of 140 nm was used as the light source. The composite
interferometer comprises two Michelson interferometers sharing common light source, reference arm and photodetector.
One of the two interferometers served as a typical OCM system and the other was used to measure the phase shift in the
reference arm in each axial scan with the sample being a fixed reflection mirror. The system was used to image the
surface profiles of various immersed biological samples with accuracy at nanometer scale through the self-phasecompensation
mechanism.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Citation
Chun-Wei Chang and I-Jen Hsu
"Composite low-coherence interferometer for imaging of immersed tissue with high accuracy", Proc. SPIE 8493, Interferometry XVI: Techniques and Analysis, 84930A (September 13, 2012); doi:10.1117/12.929126; http://dx.doi.org/10.1117/12.929126
