Polarized material inspection apparatus
US5742392A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 1996 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Apr 16, 2016 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/442
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Light reflected from skin has two components: regular reflectance, or "glare" arising from the surface, and light backscattered from within the tissue. The regular reflectance contains the visual cues related to surface texture, whereas the backscattered component contains the cues related to pigmentation, erythema, infiltrates, vessels and other intracutaneous structures. Unlike the backscattered component, regular reflectance preserves the plane of polarization of polarized incident light. Thus, viewing skin through a linear polarizer, under linearly polarized illumination, separates the two components of tissue reflectance. When the planes of polarization are parallel, images with enhanced surface detail are obtained. When the planes are orthogonal, wrinkles and surface detail disappear, and an enhanced view of vasculature and pigmented lesions is obtained. Apparatus for performing such inspection is disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.