Biomedical subjects

Hidenao Iwai

Publications and source records attributed to Hidenao Iwai.

3 recordsLinked to original sources

PubMed2006

Full-field quantitative phase imaging by white-light interferometry with active phase stabilization and its application to biological samples.

We report a Koehler-illumination-based full-field, actively stabilized, low-coherence phase-shifting interferometer, which is built on a white-light Michelson interferometer. By using a phase-stepping technique we can obtain full-field phase images of the sample. An actively stabilized phase-lock circuit is employed in the system to reduce phase noise. An application to human epithelial cells (HeLa cells) is achieved in our experiment. The advancement of this technique rests in its ability to take images of unstained biological samples quantitatively and on a nanometer scale.

Equipment Design↗

PubMed2004

Fourier phase microscopy for investigation of biological structures and dynamics.

By use of the Fourier decomposition of a low-coherence optical image field into two spatial components that can be controllably shifted in phase with respect to each other, a new high-transverse-resolution quantitative-phase microscope has been developed. The technique transforms a typical optical microscope into a quantitative-phase microscope, with high accuracy and a path-length sensitivity of lambda/5500, which is stable over several hours. The results obtained on epithelial and red blood cells demonstrate the potential of this instrument for quantitative investigation of the structure and dynamics associated with biological systems without sample preparation.

Cells, Cultured↗

PubMed2004

Quantitative phase imaging using actively stabilized phase-shifting low-coherence interferometry.

We describe a quantitative phase-imaging interferometer in which phase shifting and noise cancellation are performed by an active feedback loop using a reference laser. Depth gating via low-coherence light allows phase measurement from weakly reflecting biological samples. We demonstrate phase images from a test structure and living cells.

Equipment Design↗