Evaluation of the curing process of Ultraviolet (UV) curable adhesive by using phase-shifting digital holography is proposed. In digital holography, interference fringes produced by the reference wave and the object wave reflected from the adhesive film are recorded sequentially as hologram over a period of time and the curing process of adhesive is analyzed from the phase difference of two successive reconstructed complex amplitudes of the object waves. The variation of phase image obtained by digital holography is followed during the hardening process of adhesive. It is shown that the local variation of hardening process can be visualized and analyzed numerically. Experimental analysis is conducted with a constant UV light intensity.Correlation between the UV light intensity and the hardening process obtained by digital holography is discussed in this paper.

In this paper, the method to evaluate the distribution of bright materials contained in multilayer coating on car body panels using low coherence digital holography is proposed. In comparison with the conventional methods based on either confocal microscopy or optical coherent tomography, the proposed method can achieve both surface profile measurement and wider measurement area of car body panels. In this method, the reconstructed amplitude and the phase distribution of the object wave reflected from each paint layer can be obtained and used for investigating both the surface profile of the coating film and the distribution of bright materials in the desired paint layer. It is shown that the thickness of the clear paint layer on two pieces of gray car-body-panels having the different appearance is different and the depth distribution of the bright materials shows a local variation in both body-panels. In addition, by comparing the results with optical microscope observation, it is suggested that the paint appearance depends on the thickness of the clear coat layer in the car-body-panel.

Frequency-Modulated Continuous-Wave (FMCW) technique has been introduced into digital holography (DH) by using an injection-current-induced frequency modulation of a laser diode (LD) as a light source. Since the frequency of beat signals observed in time series holograms captured by a high speed digital camera depends on the optical path length difference between the reference and the object light waves, the introduction of FMCW technique into DH makes it possible to multiple record the object information in time-frequency domain. By the technique, a polarization state of the object wave transmitting through a PMMA sample was investigated using the proposed technique in which the object wave interfered with two orthogonally linearly polarized reference waves having the different optical path lengths.キーワード：ディジタルホログラフィ，FMCW，偏光解析.

Movement of an optical component such as a mirror or a beam splitter glued by Ultraviolet (UV) curable adhesive on a metal plate has been investigated by using phase-shifting digital holography. When the optical mirror cube is glued on the metal plate under the illumination of UV-LED light beam, interference fringes produced by the reference wave and the reflected wave from the mirror surface are recorded sequentially as hologram over a period of time and movement of the mirror cube is analyzed from the phase difference of two successive reconstructed complex amplitudes of the reflected waves. The movement of the mirror cube in the hardening process of UV curable adhesive has been followed. It is shown that the movement of the mirror cube can be analyzed by using both the magnitude and the orientation of the vector normal to the displacement of the mirror detected by digital holographic interferometry. Experimental analysis is conducted with a constant UV light intensity. Correlation between the orientation of UV light illumination and the movement of the mirror cube obtained by digital holography is discussed in this paper.

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