Fastest Thickness Measurements with Terahertz Pulses – TeraFlash smart: Ultrafast Time-Domain Terahertz Platform

14 Jun 2019

TOPTICA's new time-domain terahertz system TeraFlash smart sets new standards in terms of measurement speed: The system records up to 1600 pulse tracks per second, enabling real-time layer thickness measurements even on rapidly moving samples.

In contrast to conventional terahertz time-domain spectrometers, the TeraFlash smart does not use any mechanical delay unit, but includes two synchronized femtosecond lasers with an electronic delay (“electrically controlled optical sampling”, ECOPS).

Within a measurement time of only 625 µs, the TeraFlash smart achieves a spectral bandwidth of 3 THz. The dynamic range of the pulse trace is greater than 50 dB. Within one second of averaging, this value increases to > 80 dB and the bandwidth exceeds 4 THz. Users can flexibly adjust the terahertz path length from 10 cm to 180 cm.

Due to its high measurement speed, the TeraFlash smart lends itself to non-destructive testing of rapidly moving samples, e.g. in settings that involve conveyor belts or extrusion lines. The fiber-coupled transmitter and receiver antennas can be flexibly positioned and enable measurements in transmission or reflection.

Reflection measurements are particularly suitable to determine layer thicknesses, for example to investigate the wall thickness of plastic pipes, or the structure of polymer coatings or single- and multi-layered paint. The 10 m long fiber cables allow a spatial separation of the control unit from the measurement head, which can even be mounted on a robot arm.