Abstract

Previously, we demonstrated an intense THz-ra- diation source from a femtosecond laser irradiated InAs in a magnetic field with shallow incidence angle.^1–5 From this system, THz-radiation intensity achieved about 100-μW at magnetic field around 3 T. This THz-radiation intensity is sufficient strong for most application and detectable even with a thermal receiver. The printing is one of the traditional and huge industries. For printing applications, the simultaneous control of thickness and water content of black ink films is key issue. An adjustment of thickness and water content of black ink on the ink rollers in a printing machine still depends on the trained craftsperson. This bottleneck significantly increases the cost and limits the easy mass-production capability. In this presentation, we demonstrate the simple, non-contact and simultaneous measurement for thickness and water content of black ink films using THz radiation.

© 2002 Optical Society of America