Vibration Phase Measurements using Holographic Optical Elements

The application of an out-of-plane sensitive electronic speckle pattern interferometer (ESPI) using holographic optical element (HOE) to vibration amplitude and phase mapping is reported. The novelty of the proposed system is the use of a speckle reference wave stored in a reflection holographic optical element (HOE). The incorporation of a HOE minimizes the alignment difficulties. The HOE based ESPI system is compact containing only a diode laser, HOE and a digital CMOS camera. The measurement technique is a combination of time averaged ESPI and reference beam phase modulation in an unbalanced interferometer. The reference beam phase modulation is implemented by modulating the drive current of the diode laser. The presented HOE based ESPI system is easy to align and compact and thus suitable for industrial non-destructive testing and vibration analysis.

[1]  Vincent Toal,et al.  Out-of-plane vibration analysis with a transmission holographic-optical-element-based electronic speckle pattern interferometer , 2009, Optical Metrology.

[2]  Vincent Toal,et al.  Multipoint laser Doppler vibrometry using holographic optical elements and a CMOS digital camera. , 2008, Optics letters.

[3]  P. Hariharan,et al.  Holographic and Speckle Interferometry , 2007 .

[4]  Ventseslav Sainov,et al.  Compact electronic speckle pattern interferometer using a near infrared diode laser and a reflection holographic optical element , 2006 .

[5]  Vincent Toal,et al.  Detection of cracks and defects using electronic speckle pattern interferometry with a holographic optical element , 2003, International School on Quantum Electronics: Laser Physics and Applications.

[6]  Krzysztof Patorski,et al.  Modified electronic speckle pattern interferometer with reduced number of elements for vibration analysis , 1997 .

[7]  Ralph P. Tatam,et al.  Heterodyning of fibre optic electronic speckle pattern interferometers using laser diode wavelength modulation , 1994 .

[8]  John R. Tyrer,et al.  Whole field in-plane vibration analysis using pulsed phase-stepped ESPI. , 1991, Applied optics.

[9]  John R. Tyrer,et al.  An electronic speckle pattern interferometer for complete in-plane displacement measurement , 1990 .

[10]  O J Løkberg,et al.  Vibration phase mapping using electronic speckle pattern interferometry. , 1976, Applied optics.

[11]  O J Lokberg,et al.  Use of modulated reference wave in electronic speckle pattern interferometry , 1976 .