Development of Phase Shifting Device Using the Deflection of a Cantilever for Digital Holography

2006 ◽  
Vol 326-328 ◽  
pp. 19-22
Author(s):  
Hitomi Matsukawa ◽  
Motoharu Fujigaki ◽  
Toru Matui ◽  
Yoshiharu Morimoto

Phase-shifting digital holography can be used for displacement measurement instead of strain gauge. Our research group is developing the measurement equipment for phase-shifting digital holography. Generally, in the measurement equipment, piezo stages are used as phaseshifting devices. But the piezo stage is expensive. Cheaper and smaller phase-shifting device is required in order to put the measurement equipment into practical use. In this paper, we, therefore, propose a phase-shifting device using the deflection of a cantilever and we verify whether this phase-shifting device can be usedfor digital holography.

2006 ◽  
Vol 3-4 ◽  
pp. 211-216
Author(s):  
T. Kita ◽  
Yoshiharu Morimoto ◽  
Motoharu Fujigaki ◽  
Toru Matui

Displacement measurement can be performed with high accuracy using phase-shifting method. In phase-shifting method, it is often used four steps of phase-shifting for one cycle. In conventional method, to measure the displacement of an object by an interferometer, the phase of a reference beam should be shifted by every π/2 in the four-step phase-shifting. In this paper, a phase-shifting method with unknown intervals is proposed. This method does not need to shift a phase by every π/2. It can detect an intensity distribution and a phase distribution from five fringe images with equal intervals even if the phase-shift amount is unknown. Using this method, we propose a displacement measurement of phase-shifting digital holographic interferometry using spherical wave as reference wave.


2003 ◽  
Vol 2003.9 (0) ◽  
pp. 175-176
Author(s):  
Isao TAKAHASHI ◽  
Yoshiharu MORIMOTO ◽  
Takanori NOMURA ◽  
Satoru YONEYAMA ◽  
Motoharu FUJIGAKI

2010 ◽  
Vol 6 (10) ◽  
pp. 472-478 ◽  
Author(s):  
Takashi Kakue ◽  
Kenichi Ito ◽  
Tatsuki Tahara ◽  
Yasuhiro Awatsuji ◽  
Kenzo Nishio ◽  
...  

2006 ◽  
Author(s):  
Sang Keun Gil ◽  
Seok Hee Jeon ◽  
Nam Kim ◽  
Jong Rae Jeong

Author(s):  
Roghayeh Yazdani ◽  
Hamidreza Fallah

In digital holography, errors of the reference field degrade the quality of the reconstructed object field. In this paper, we propose an effective method in phase-shifting digital holography in which the reference field does not need to be known and perfect. The unknown complex amplitudes of both reference and object fields are derived simultaneously. The method employs only five digital holograms and a single execution of a phase retrieval algorithm. So, the required measurements and algorithm executions in this method are fewer than those in other methods; it suggests a simpler and faster method. The effectiveness of the suggested method is indicated by simulation, under noise-free and noisy conditions. Moreover, the capability of the method to extract full information about the phase singularities in both fields is demonstrated.


Sign in / Sign up

Export Citation Format

Share Document