Uneven-surface data detection apparatus
US4924085A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 1989 |
| Grant date | May 8, 1990 |
| Priority date | — |
| Expiry date | Jun 23, 2009 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/1172
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An uneven surface data detection apparatus for detecting an uneven surface, such as a human finger, having projected portions and recessed portions. A transparent base having upper and lower surfaces and an upper surface defining an uneven surface contact portion is provided, and a light is incident on the uneven surface so that the light derived from the recess portions enters to the transparent base and comes out thereof. However, a part of the light derived from the projected portions is totally reflected at least one time by the lower opposite surface and focussing lens is integrally formed on the transparent base so that the totally reflected light is drawn out of transparent base and enters to an image sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.