Digital flash intensity control system for phototypesetters
US4051486A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 3, 1975 |
| Grant date | Sep 27, 1977 |
| Priority date | — |
| Expiry date | Nov 3, 1995 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41B21/12
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
For variable letter sizes being photographically recorded in a second generation phototypesetter, it is desired to increase generated quantities of light flux produced by the flash lamp operating in conjunction with a font disc where larger letter sizes are thereby imaged upon the photosensitive medium, and conversely, to reduce such flux where smaller characters are to be projected. The disclosed system employs a digital letter size code for controlling the amount of charge inserted into a storage capacitor via a digital to analog converter and multivibrator. When the flash lamp is triggered at the appropriate time to selectively illuminate a given character, the energy associated with the stored charge is employed to energize the lamp.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.