Patent ID: 7446789
Filing Date: 2008-11-04
Classification: B41J

Abstract:
1. A heat accumulation correcting method of correcting heat accumulation of a thermal head for thermal recording, wherein said thermal head has an array of heating elements arranged in a main scan direction, for image recording on recording material by one line in driving of said heating elements according to heat data, wherein one of said thermal head and said recording material is moved relative to a remaining one thereof in a sub scan direction in recording of said line, said heat accumulation correcting method comprising steps of: wherein said thermal head has first to Lth heat accumulating layers lying over one another, said first layer having said heating elements thereon; wherein a first specific point of said first to Lth layers is predetermined commonly behind said heating elements in a thickness direction thereof, and a second specific point is predetermined in at least one of said first to Lth layers and offset from said first specific point in said sub scan direction; processing initial heat data of an Mth line, and heat accumulation correcting data for said first and second specific points in said first to Lth layers in relation to said Mth line, to determine said heat data adapted to driving said heating elements to print said Mth line; and processing said determined heat data and accumulated heat data related to heat accumulation of said first and second specific points of said first to Lth layers in printing said Mth line, according to a predetermined linear function, to determine accumulated heat data of said first and second specific points of said first to Lth layers for said (M+1)th line, and for multiplying said accumulated heat data by a coefficient, to determine heat accumulation correcting data for said (M+1)th line.