Patent ID: 6721531
Filing Date: 2004-04-13
Classification: G03G

Abstract:
A flash fixing apparatus for flash-fixing a toner image onto a medium being carried at a predetermined carriage velocity, comprising:a flash fixing unit having a flash lamp and a reflection plate disposed to surround said flash lamp excluding at an aperture portion, so as to reflect light from said flash lamp to direct toward said aperture portion; and a controller for controlling to flash said flash lamp, wherein said flash fixing unit has a flash energy distribution on the medium, that is produced by a single flash of said flash lamp, the flash energy distribution having substantially a constant value at a center zone of said flash energy distribution and decreasing values at both a front zone and rear zone thereof as each position therein becomes farther from said center zone, wherein the flash fixing unit flashes at a flash frequency f such that the rear zone of one flash overlaps the front zone of a succeeding flash within a superposition zone on the medium; wherein a fusion energy distribution is obtained by subtracting a fixing start energy &bgr; from said flash energy distribution; and and wherein said controller controls a said flash frequency f such that said fusion energy distribution within the superposition zone is substantially equal to a fusion energy distribution within the center zone that is outside the superposition zone, whereby fusion energy is substantially uniform across the medium.