Iris image acquisition system
US11209633B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 7, 2018 |
| Grant date | Dec 28, 2021 |
| Priority date | — |
| Expiry date | Mar 23, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/55
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An iris image acquisition system for a mobile device, comprises a lens assembly arranged along an optical axis and configured for forming an image comprising at least one iris of a subject disposed frontally to the lens assembly; and an image sensor configured to acquire the formed image. The lens assembly comprises a first lens refractive element and at least one second lens element for converging incident radiation to the first refractive element. The first refractive element has a variable thickness configured to counteract a shift of the formed image along the optical axis induced by change in iris-lens assembly distance, such that different areas of the image sensor on which irises at different respective iris-lens assembly distances are formed are in focus within a range of respective iris-lens assembly distances at which iris detail is provided at sufficient contrast to be recognised.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.