To combat this, the researchers used an NIR-absorbant cyanine dye that exhibits rapid photocuring. The team reports times of 60 seconds per layer and resolution as high as 300 micrometers.

These absorbance and emission spectra can not only exist within the visible spectrum, but also in ultraviolet (UV) and near infrared (NIR). Additionally, fluorescent dyes are highly sensitive, ...

dyes and finishes (sourced straight from the thrift store). The cumulative 64 fabrics types' NIR "fingerprints" are documented as well. "This reference data will help improve sorting algorithms ...