| Summary: | 碩士 === 國立成功大學 === 航空太空工程學系 === 85 === The purpose of this research is to apply the white light
reconstruction technique on the double-exposure holographic
interferometry of phase objects. Here are two white light
reconstruction techniques.They are the one-step rainbow
technique and the volume reflection technique. Where the
method to make white light reconstruction of one-step rainbow
hologram is using the property of spatial filtering. The method
to make white light reconstruction of volume reflection hologram
is using the Bragg effect of three-dimensional gratings to
filter light of different wavelengths. I choose volume
reflection hologram as the white light reconstruction technique
to apply on double-exposure holographic interferometry of phase
object according to the light amplitude where the hologram
displays. In double-exposure holographic interferometry
,interference takes place between the wave fronts reconstructed
by two holograms of the object recorded on the same photographic
plate. In this experiments ,the first exposure is made with the
phase object in its initial state ,and the second is made when
the phase object was heated. In this research using the
He-Ne laser as the recording light source. White light as the
reconstruction light source. Agfa 8E75 as the recording
material. The phase object(test section) of the
holographic interferometry is the air which light pass through
in dark room. The phase difference at any point in the
interference pattern is due to the variation of the refraction
index of the two exposures.The case which can be analytic
treated is that the refractive index distribution which is
radial symmetric about an axis normal to the line of sight.
Here I use a three-order function to map the radial symmetric
refraction index of air . Under a simple calculation
process compared with the numerical analysis ,I got a similar
temperature distribution with the data measured directly by
thermocouple.
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