Limits of Digital Holographic Interferometry used for Measurement of Temperature Fields

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F46747885%3A24210%2F18%3A00006045" target="_blank" >RIV/46747885:24210/18:00006045 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/46747885:24220/18:00006045

Výsledek na webu

<a href="https://www.iaras.org/iaras/filedownloads/ijap/2018/015-0009(2018).pdf" target="_blank" >https://www.iaras.org/iaras/filedownloads/ijap/2018/015-0009(2018).pdf</a>

DOI - Digital Object Identifier

—

Jazyk výsledku

angličtina

Název v původním jazyce

Limits of Digital Holographic Interferometry used for Measurement of Temperature Fields

Popis výsledku v původním jazyce

Holographic interferometry (HI) is an optical measurement method that combines the principles of holography and classical interferometry. Compared to classical interferometry, two significant benefits are achieved. The first advantage is the ability to measure diffuse reflecting surfaces of objects, but this is not a matter of phase measurement. The second advantage is the fact that this is a differential technique. In principle, holographic interferometry, similar to classical interferom etry, measures the change in the optical path of two waves. However, in classical interferometry, both optical paths of the interferometer must be optically equivalent, which means minimal difference in optical paths at each point. The resulting interferometric pattern is a combination of the measured deviation and variance introduced by the interferometer. Both deviations cannot be distinguished from one another. For this reason, the interferometer must be composed of highly accurate optical components and adjusted with high precision. In the case of HI, an initial reference state is recorded at first, than it is compared to the changed (in the optical point of view) state of the object. The optical inequality of both paths does not play a role and does not affect the measurement result. Digital holographic interferometry, compared with HI, uses numerical reconstruction of a hologram which is recorded on a digital camera. The presented paper shows an overview of different modes and configurations of digital holographic interferometry (DHI) for precise measurement of temperature fields in fluids. It shows basic equations used for evaluation of achieved results and for the reconstruction of temperature fields. The paper shows basic configuration of interferometers (Mach-Zehnder and Twyman-Green) used for DHI. Paper also brings analysis of physical limits of the experimental method.

Název v anglickém jazyce

Limits of Digital Holographic Interferometry used for Measurement of Temperature Fields

Popis výsledku anglicky

Holographic interferometry (HI) is an optical measurement method that combines the principles of holography and classical interferometry. Compared to classical interferometry, two significant benefits are achieved. The first advantage is the ability to measure diffuse reflecting surfaces of objects, but this is not a matter of phase measurement. The second advantage is the fact that this is a differential technique. In principle, holographic interferometry, similar to classical interferom etry, measures the change in the optical path of two waves. However, in classical interferometry, both optical paths of the interferometer must be optically equivalent, which means minimal difference in optical paths at each point. The resulting interferometric pattern is a combination of the measured deviation and variance introduced by the interferometer. Both deviations cannot be distinguished from one another. For this reason, the interferometer must be composed of highly accurate optical components and adjusted with high precision. In the case of HI, an initial reference state is recorded at first, than it is compared to the changed (in the optical point of view) state of the object. The optical inequality of both paths does not play a role and does not affect the measurement result. Digital holographic interferometry, compared with HI, uses numerical reconstruction of a hologram which is recorded on a digital camera. The presented paper shows an overview of different modes and configurations of digital holographic interferometry (DHI) for precise measurement of temperature fields in fluids. It shows basic equations used for evaluation of achieved results and for the reconstruction of temperature fields. The paper shows basic configuration of interferometers (Mach-Zehnder and Twyman-Green) used for DHI. Paper also brings analysis of physical limits of the experimental method.

Druh

O - Ostatní výsledky

CEP obor

—

OECD FORD obor

10306 - Optics (including laser optics and quantum optics)

Projekt

<a href="/cs/project/GA16-16596S" target="_blank" >GA16-16596S: Optimalizace generování pulzujících proudů v mechanice tekutin</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů