Optical Alignment for Non-contact In vivo THz Sensing

A key obstacle to the non-contact measurement of in vivo skin samples is the alignment of reflected THz pulses. The inevitable movements of participants during in vivo measurements significantly affects the reflected THz response. This work introduces a new protocol for non-contact measurements in which, counterintuitively, the sample is deliberately moved. We then apply an algorithm to determine the most probable sample properties. We demonstrate proof of concept with a plastic disc, as we can also characterize this in transmission to validate our results.