![HDRS](https://schrader-institute.de/wp-content/uploads/2023/01/hdrs-300x225.jpg)
HDRS – Hybrid Diffuse Reflectance Spectroscopy
In order to define a label SPF of topically applied sunscreens in vivo test methods like ISO 24444, FDA-Guideline, or the Australian Standard are used worldwide. Basis of all these methods is provoking …