Terahertz Ray System Calibration and Material Characterizations

Chiou, Chien‐Ping; Blackshire, James L.; Thompson, R. B.

doi:10.1063/1.3114262

Cited by 15 publications

(18 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The focal lengths of the CW system are also 50mm and 150mm. Both the TDS and the CW systems are fully fiber optics connected [1,11,12].…”

Section: Methodsmentioning

confidence: 99%

“…The terahertz radiation is of critical importance in the spectroscopy evaluation of airport security screening, medical imaging, polar liquids, industrial systems and composites as well [1]. Also the terahertz time domain spectroscopy (TDz-TDS) is leading noncontact and accurate detection of defects and impact damages in composites [2], in which the TDz-TDS is based on photoconductive switches, which rely on the production of few-cycle terahertz pulses using a femtosecond laser to excite a photoconductive antenna [3].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Influence of terahertz waves on the penetration in thick FRP composite materials

Hsu

Chiou

et al. 2014

AIP Conference Proceedings

Self Cite

View full text Add to dashboard Cite

Fiber reinforced plastics (FRP) are increasingly utilized in engineering structures because of their performance and fabrication advantages. With this increased utilization, a technique to gage quality and further characterize the materials would be beneficial. The nondestructive applications for Terahertz (T-ray) methods have also experienced increased utilization for evaluating engineering materials and will be reported on here in applications for the inspection and characterization of FRP materials used in wind energy components. First, refraction and transmission T-ray modes are used to determine the refractive index (n) of a glass fiber reinforced plastic (GFRP) reference sample, and extended for calculating the refractive indices for a sample of GFRP, balsa and epoxy. Additionally, carbon fiber reinforced plastic (CFRP) samples were evaluated with respect to fiber directions versus T-ray electric field polarization direction to evaluate the level of penetration of T-ray energy due to the fiber orientation dependent conductivity of this composite material. Finally, an evaluation of T-ray data was made to evaluate resonance effects, where the resonance frequency was found to agree with that expected from reflections from individual plies in thick GFRP laminates.

show abstract

“…The focal lengths of the CW system are also 50mm and 150mm. Both the TDS and the CW systems are fully fiber optics connected [1,11,12].…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Influence of terahertz waves on the penetration in thick FRP composite materials

Hsu

Chiou

et al. 2014

AIP Conference Proceedings

Self Cite

View full text Add to dashboard Cite

show abstract

“…The terahertz radiation is of critical importance in the spectroscopy evaluation of airport security screening, medical imaging, polar liquids, industrial systems and composites as well [1]. Also the terahertz time domain spectroscopy (TDz-TDS) is leading noncontact accurate detection of flaws and impact damages in composites, in which the TDz-TDS is based on photoconductive switches, which rely on the production of few-cycle terahertz pulses using a femtosecond laser to excite a photoconductive antenna [2].…”

Section: Introductionmentioning

confidence: 99%

Nondestructive and noncontact evaluation on FRP composite laminates using a terahertz ray

Park

Hsu

et al. 2012

SPIE Proceedings

Self Cite

View full text Add to dashboard Cite

Recently, a terahertz ray (T-ray) technique has emerged as one of the most promising new powerful nondestructive evaluation (NDE) techniques, and new application systems are under processing development for the area applications. In this study T-ray technique will be adopted for the characterization of the FRP composite solid laminates as an imaging and useful nondestructive evaluation (NDE) tool. So, in order to detect and evaluate the flaws in FRP solid composite laminates a new time-domain spectroscopy system was utilized. Various experimental measurements in reflection and through-transmission modes were made in order to map out the T-ray images. Especially in this characterization procedure, we estimated the electromagnetic properties such as the refractive index and a couple of techniques were proposed to measure the refractive index. It is found that estimations of properties with the proposed different ways are in good agreement with known data. Furthermore woven CFRP Honey comb sandwich panel with Al wire were observed in reflection mode and limitations will be mentioned in the T-ray processing.

show abstract

“…Recently, T-ray (terahertz ray) advances of technology and instrumentation has provided a probing field on the electromagnetic spectrum. The terahertz radiation is of critical importance in the spectroscopy evaluation of airport security screening, medical imaging, polar liquids, industrial systems and composites as well [1]. Also the terahertz time domain spectroscopy (THz-TDS) is leading noncontact accurate detection of flaws and impact damages in composites, in which the THz-TDS is based on photoconductive switches, which rely on the production of few-cycle terahertz pulses using a femtosecond laser to excite a photoconductive antenna [2][3][4].…”

Section: Introductionmentioning

confidence: 99%

Terahertz radiation study on FRP composite solid laminates

Im¹,

Hsu²,

Chiou³

et al. 2012

AIP Conference Proceedings

Self Cite

View full text Add to dashboard Cite

Investigation of terahertz time domain spectroscopy (THz TDS) was made and reflection and transmission configurations were studied as a nondestructive evaluation technique. Here carbon fiber-reinforced plastics (CFRP) derived their excellent mechanical strength, stiffness and electrical conductivity from carbon fibers. Especially, the electrical conductivity of CFRP composites depends on the direction of unidirectional fibers since carbon fibers are electrically conducting while the epoxy matrix is not. The THz TDS can be considered as a useful tool using general non-conducting materials; however it is quite limited to conducting materials. In order to solve various material properties, the index of refraction (n) is derived by using the terahertz time domain spectroscopy. Also, for a 48-ply thermoplastic PPS(poly-phenylene sulfide)-based CFRP solid laminate, the terahertz scanning images were made at the angles ranged from 0° to 180° with respect to the nominal fiber axis. So, the images were mapped out based on the electrical field (E-field) direction in the CFRP solid laminates. ABSTRACT. Investigation of terahertz time domain spectroscopy (THz TDS) was made and reflection and transmission configurations were studied as a nondestructive evaluation technique. Here carbon fiberreinforced plastics (CFRP) derived their excellent mechanical strength, stiffness and electrical conductivity from carbon fibers. Especially, the electrical conductivity of CFRP composites depends on the direction of unidirectional fibers since carbon fibers are electrically conducting while the epoxy matrix is not. The THz TDS can be considered as a useful tool using general non-conducting materials; however it is quite limited to conducting materials. In order to solve various material properties, the index of refraction (n) is derived by using the terahertz time domain spectroscopy. Also, for a 48-ply thermoplastic PPS(poly-phenylene sulfide)-based CFRP solid laminate, the terahertz scanning images were made at the angles ranged from 0 o to 180 o with respect to the nominal fiber axis. So, the images were mapped out based on the electrical field (E-field) direction in the CFRP solid laminates.

show abstract

Terahertz Ray System Calibration and Material Characterizations

Cited by 15 publications

References 0 publications

Influence of terahertz waves on the penetration in thick FRP composite materials

Influence of terahertz waves on the penetration in thick FRP composite materials

Nondestructive and noncontact evaluation on FRP composite laminates using a terahertz ray

Terahertz radiation study on FRP composite solid laminates

Contact Info

Product

Resources

About