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Thank you for your continued interest in the next generation of gold standard SPF Test and Measurement Solutions from Solar Light!
In Polychromatic Diffuse Reflectance Spectroscopy (PDRS), a polychromatic source illuminates the skin via a custom light guide array, and the diffuse reflected light is measured with a photomultiplier. The measured diffuse reflectance intensity with and without the sunscreen on the skin determines the polychromatic diffuse reflectance UVA-PF (PDRS UVA-PF0).
Polychromatic HDRS is a rapid, noninvasive technique to accurately determine both UVA-PF and SPFs without high doses of UV radiation necessary with traditional erythemal test methods.
To learn more, click the link below to read a recent article on Polychromatic Diffuse Reflectance Spectroscopy and how it correlates to HDRS (ISO/CD 23698): Cole C, Silverman J, Bonitatibus M. Evaluating sunscreen ultraviolet protection using a polychromatic diffuse reflectance device. Photodermatol Photoimmunol Photomed. 2019;35:436–441..
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