Visual and dynamic measurement of temperature fields by use of digital holographic interferometry

The measurement of temperature field distribution in transparent media is an attracting subject in many research fields. In transparent medium, the temperature change will induce a corresponding refractive index change and thus lead to the phase distribution and variation of the object wavefront passing through the medium. Different from the traditional optical holographic interferometry, the recently developed digital holographic interferometry allows recording the hologram using digitally imaging devices such as CCD, and reconstructing the holographic image by numerically simulating beam diffraction, so it can directly obtain the complex amplitude distribution of the object wavefront in different states by dynamically recording a series of holograms of the object field in different time. Then more detail information can be calculated, such as the refractive index distribution and variation in transparent media. In this paper, we introduce the principles and review some of the applications on dynamically measuring the temperature field distribution by using digital holographic interferometry with specially designed experimental setups, such as the temperature distributions and variations corresponding to Rayleigh-Benard convection, heat conduction process in glass samples, heating process of the oil in container, flame filed, cooling process of heat sink and so on.