Improved flash lockout
US5432585A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1993 |
| Grant date | Jul 11, 1995 |
| Priority date | — |
| Expiry date | Aug 31, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B15/05
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A camera locks out an attempted flash photograph when the voltage of the flash charger is below a minimum voltage necessary for the flash to fire. Flash lockout may also take place when: the flash charger voltage is equal to or greater than the minimum flash voltage but less than the lowest voltage in a voltage range providing optimum flash lighting; and the photographic subject distance is beyond the flash range at the present flash charger voltage. Lockout may also be determined based on current flash charger charging time compared to predetermined times for the flash charger to reach the minimum voltage and/or the lowest voltage in the optimum lighting range from a substantially discharged state.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.