June 14-18th

Four talks will be hold and two posters presented at Photonics Europe in Munich, Germany from June 14-18th.

A DHM T1000 will also be presented by our distributor Schaefer Tec and Lyncée Tec on booth B2.543 at SPIE Laser World of Photonichs 2009.

SPIE Europe Optical Metrolog

• "Several micron range measurements with sub-nanometric resolution by the use of dual-wavelength digital holography and vertical scanning",
  T.Colomb, 7389-54, 18 June - 08:40
  
• "Depth-of-field extension and 3D reconstruction in digital holographic microscopy",
  I. Bergoënd, 7390-49 (poster), 15 June - 16:30

• "Optical Tomography by Digital Holographic Microscopy",
  N. Pavillon, SuC3, 14 June - 16:15
• "Digital Holographic Microscopy at Fundamental and Second Harmonic Wavelengths",
  E. Shaffer, TuK3, 16 June - 14:15
• "Monitoring the Dynamics of Cell with Digital Holographic Microscopy",
  P. Marquet, TuK4, 16 June 14:30
  
• "Endoscopic Low Coherence Interferometry in Upper Airways",
  Y. Delacrétaz, MJ38 (Poster), 15 June - 15:00

Abstracts:

Several micron range measurements with sub-nanometric resolution by the use of dual-wavelength digital holography and vertical scanning
Reflection DHM is a powerful technique measuring topography with a sub-nanometer axial resolution from a single hologram acquisition. But, the vertical range is limited to half the wavelength when unwrapping procedure can’t be applied. Nevertheless, dual-wavelength DHM allows increasing the range up to several microns by saving the single wavelength resolution if conditions about phase noise are fulfilled. We demonstrate that a synthetic wavelength of about 17um allows measuring precisely a 4.463um certified step; and show the feasibility of a sub-nanometer resolution on a range higher than the synthetic wavelength by mapping the dual-wavelength measurement on data acquired from a vertical scanning process.

Depth-of-field extension and 3D reconstruction in digital holographic microscopy
The limited depth-of-field is a main drawback in microscopy. The algorithms developed to compute a completely focalized image with virtually extended depth-of-field from a stack of partially focalized images can lead to improved results when applied to digital holographic microscopy.
A comparison of such algorithms is presented using phase images of a biological specimen, taking advantage of several properties of holography. A quantitative measurement and a visual criterion are considered.
From this process of focalization, a method of 3D information extraction is deducted. It is compared with the reconstruction of 3D shapes using the quantitative phase information.

Optical Tomography by Digital Holographic Microscopy
Three-dimensional imaging coupled with quantitative phase signal gives rise to 3-D refractive index reconstruction, leading to interesting perspectives for cell observation. We present results of tomographic measurements, taken in the framework of digital holography.

Digital Holographic Microscopy at Fundamental and Second Harmonic Wavelengths
We report on multi-functional second harmonic generation digital holographic microscopy, and present its application to determination of (1) 3-D-position and (2) nature of nanoparticles (here polystyrene microspheres and barium titanate nanoparticles).

Monitoring the Dynamics of Cell with Digital Holographic Microscopy
Digital holographic microscopy, by providing a quantitative phase signal, has permitted to investigate cellular membrane nano-fluctuations of red blood cells as well as to non-invasively monitor an optical signature of the electrical activity of cells.

Endoscopic Low Coherence Interferometry in Upper Airways
We introduce endoscopic low coherence interferometry to obtain topology of upper airways through commonly used rigid endoscopes. Our device is fully compatible with procedures used in day-to-day examinations and can potentially be brought to bedside.