Transmisní holografický mikroskop - charakteristiky zobrazení

Transmission Holographic Microscope - Image Characteristics

conference paper

en

The intensity of the reconstructed image in the transmission holographic microscope is depth discriminated as it is in a transmission confocal microscope. The effect is the consequence of the limited coherence of the illumination – hence no scanning system is needed. As the technique is based on the incoherent holography, the phase image component may be reconstructed in addition to the intensity one. The overall imaging process is coherent. Its three-dimensional coherent transfer function is derived using the first Born approximation of the scattering theory. In order to understand clearly the imaging process of the microscope, two-dimensional imaging characteristics are derived in this paper in addition to the three-dimensional one, and images of a rectilinear slit as a model two-dimensional structure are calculated for various amounts of defocus. Theoretical axial distributions of the intensity integral are compared with the experimental ones.

Intenzita rekonstruovaného zobrazení v transmisním holografickém mikroskopu je hloubkově diskriminována podobně, jako je tomu v konfokálním mikroskopu. Protože tento jev vzniká v důsledku omezené koherence osvětlení, nemusí být mikroskop vybaven rastrovací soustavou. Protože jde o holografickou techniku, může být rekonstruována nejen intenzitní, ale také fázová složka zobrazení. Zobrazovací proces je koherentní. Teoreticky je popsán pomocí trojrozměrné koherentní funkce přenosu odvozené za předpokladu první Bornovy aproximace teorie rozptylu světla ve vzorku. Pro názornější představu o vlastnostech zobrazení jsou odvozeny také dvojrozměrné charakteristiky zobrazení a vypočteno zobrazení štěrbiny, která slouží jako modelová dvojrozměrná struktura, pro různé hodnoty jejího rozostření. Teoretické osové rozložení integrálu intenzity je porovnáno s experimentem.

The intensity of the reconstructed image in the transmission holographic microscope is depth discriminated as it is in a transmission confocal microscope. The effect is the consequence of the limited coherence of the illumination – hence no scanning system is needed. As the technique is based on the incoherent holography, the phase image component may be reconstructed in addition to the intensity one. The overall imaging process is coherent. Its three-dimensional coherent transfer function is derived using the first Born approximation of the scattering theory. In order to understand clearly the imaging process of the microscope, two-dimensional imaging characteristics are derived in this paper in addition to the three-dimensional one, and images of a rectilinear slit as a model two-dimensional structure are calculated for various amounts of defocus. Theoretical axial distributions of the intensity integral are compared with the experimental ones.

holographic applications; confocal microscopy; interference microscopy; three-dimensional microscopy

2005

01.01.2005

SPIE-The International Society for Optical Engineering

Bellingham, USA

0-8194-5951-8

14th Slovak-Czech-Polish Conference on Wave and Quantum Aspects of Contemporary optics

5945

59450V-1–59450V-6

6