Quantitative cosmetic evaluation of long-lasting foundation using multispectral imaging.

BACKGROUND

We tried to search appropriate wavelength to quantitatively evaluate the ability of long-lasting foundation using a hyperspectral imager (HSI) which can simultaneously measure position and wavelength information.

MATERIALS AND METHODS

A good reputable long-lasting foundation was applied to the skin of 10 healthy volunteers. Their skin was measured by our newly developed HSI every 2 hours from immediately after application to 6 hours. The application state of the foundation was quantified using the standard deviation of reflectance.

RESULTS

A high correlation between standard deviation and the application state of the foundation was confirmed at many wavelengths. In particular, it was suggested that by using the standard deviation of 800 nm, the application state of the foundation can be evaluated quantitatively without depending on the subject's oxygen saturation level.

CONCLUSION

By quantitatively evaluating the cosmetic-applied skin by our system, further efficiency improvement of the volunteer experiment is expected.