Full-field stress measuring method based on terahertz time-domain spectroscopy.

Terahertz wave has been used to obtain the internal information of materials due to its penetrability to optically opaque materials. In this paper, we propose a full-field stress measuring method using terahertz time-domain spectroscopy. The theoretical model of the method was established based on the stress-optical law, and the method was then validated experimentally.

DIC/Moiré hybrid method based on regular patterns for deformation measurement.

Digital Image Correlation (DIC) is a superior optical method to measure the surface deformation with a high accuracy. Currently, most researches on DIC are based on random patterns. In this paper, A DIC/Moiré hybrid method using regular patterns is proposed for deformation measurement.

Determination of plane stress state using terahertz time-domain spectroscopy.

THz wave has been increasingly applied in engineering practice. One of its outstanding advantages is the penetrability through certain optically opaque materials, whose interior properties could be therefore obtained. In this report, we develop an experimental method to determine the plane stress state of optically opaque materials based on the stress-optical law using terahertz time-domain spectroscopy (THz-TDS).

Active modulation of refractive index by stress in the terahertz frequency range.

Experimental tests are presented to investigate the stress effect on terahertz (THz) waves with a THz time-domain spectroscopy system. Through the Jones matrix method, an experimental principle is derived according to the experimental system. Experimental results indicate the linear relationship between a polytetrafluoroethylene refractive index and applied stress.