Handheld Optical System for Skin Topography Measurement Using Fourier Transform Profilometry
In medicine and cosmetics a need has arisen for an accurate, fast, simple and broadly applicable three-dimensional skin surface measuring system. A new development of such handheld optical device that uses white light Fourier transform profilometry for skin surface topography measurement is presented here. The device is based on a commercially available DSLR camera and a newly designed optical system which projects a Ronchi grating pattern on the measured surface and records its image. The 3D surface is reconstructed from a single image. The topography is described using four surface roughness parameters: mean absolute deviation Ra, root-mean-square deviation Rq skewness Rsk and kurtosis Rku. Experimental measurements were conducted on five facial skin areas, together belonging to three people, before and after the laser skin treatment therapy, to evaluate its effects on skin surface roughness. The results show the viability and usefulness of the developed optical system for skin topography measurement.