Image resolution improvement in digital holography

Image resolution improvement in digital holography

Applications to interferometric microscopy by RGB multiplexing and to lensless scanning holography.

Carlos Ferreira, Universitat de Valencia

Abstract:

During a long time the classical resolution limit of an ideal imaging system has been considered as unsurpassable. As is well known, under certain conditions, this limit can be surpassed. In this seminar, I will present two different approaches for beating the resolution limit imposed by diffraction when considering imaging systems with or without lenses under coherent illumination.
When dealing with conventional lens systems, the methods to get super resolution are mostly based on illuminating the object with tilted waves and on interferometric techniques to properly manage the phase of the recovered frequency bandpass. To avoid the time delay in the recording of the different tilted waves, we have recently proposed a new method named single-exposure interferometric microscopy by RGB multiplexing (SESRIM), that uses either a color camera or a B&W one as detector, in order to achieve one-dimensional superresolved imaging in a single CCD recording.
In addition, we have proposed a lensless object scanning holographic method (LOSH) for improving image quality when using reflective objects in lens free digital Fourier transform holography. As opposed to SESRIM method, where the holographic recording is performed in a single snapshot, LOSH method is based on the recording of multiple digital lensless holograms and their subsequent digital post-processing. This post-processing results in a synthetic image with improved resolution, field of view (FOV), signal-to-noise ratio (SNR) and depth of field (DOF).

תאריך: 
14/03/2012 - 15:00
מרצה: 
Carlos Ferreira
דוא"ל להרשמה: 
Affiliation: 
Universitat de Valencia
מיקום: 
building 1103, Room 329