Shear-unlimited common-path speckle interferometer
- Resource Type
- Article
- Authors
- Dong, Jie; Wang, Shengjia; Yetisen, Ali K.; Dong, Xingchen; Pöller, Franziska; Ong, Nicholas; Jakobi, Martin; Liu, Zhanwei; Salazar Bloise, Félix; Koch, Alexander W.
- Source
- Optics Letters; March 2020, Vol. 45 Issue: 6 p1305-1308, 4p
- Subject
- Language
- ISSN
- 01469592; 15394794
A single-aperture common-path speckle interferometer with an unlimited shear amount is developed. This unlimited shear amount is introduced when a Wollaston prism is placed near the Fourier plane of a common-path interferometer, which is built by using a quasi-${4f}$4f imaging system. The fundamentals of the shear amount and the spatial carrier frequency generation are analyzed mathematically, and the theoretical predictions are validated by a static experiment. Mode-I fracture experiments through the three-point bending are conducted to prove the feasibility and the capability of this method in full-field strain measurement with various shear amounts. A remarkable feature of this setup is that no tilt is required between the optical components to produce the unlimited shear amount in off-axis holography.