Automatic focus adjusting device
US4908645A · kind A · utility
31Cited by
6References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 2, 1989 |
| Grant date | Mar 13, 1990 |
| Priority date | — |
| Expiry date | Feb 2, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/34
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An automatic focusing device for foreseeing or predicting the position of object after a predetermined time, based on plural past focusing operations on the object, utilizing a function of a higher order, and driving a lens for focusing to the predicted object position. According to the present invention there is provided a correcting circuit for correcting the coefficients of the higher-order function to reduce the influence of the measuring errors contained in the past focusing results, thus constantly enabling appropriate focusing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.