Line printer
AssigneeFuji Photo Film Co., Ltd.
InventorKazuo Miyaji
Life of this patent
Estimating the term…
Abstract
A line printer including a device for receiving gradation scale values of pixels for one line to be printed, and a plurality of tables for correcting a density variation caused by common resistance unevenness. The line printer further includes a device for arithmetically obtaining a number of printing elements to be operated for each gradation scale for printing from the gradation scale values of the pixels for one line received by the receiving device, and a device for retrieving an optimal table from the plurality of tables on the basis of the number of printing elements obtained by the arithmetic device.
Claims15
A line printing method for a line head having a plurality of heating elements and capable of printing with a plurality of gradation scale values comprising the steps of:
- a) storing received gradation scale values of pixels for a line to be printed;
- b) determining the number of pixels of the line to be printed for each respective gradation scale value;
- c) determining the number of heating elements to be heated for each respective gradation scale value for the line to be printed based on the number of pixels determined in said step b);
- d) storing a plurality of tables for correcting a density variation in a printed line caused by common resistance unevenness;
- e) retrieving an optimal table for each respective gradation scale value for the line to be printed based upon a gradation scale value and the number of heating elements to be heated for the respective gradation scale value as determined in said step c);
- and
- f) controlling the line head to print the line in accordance with the retrieved optimal tables.
A line printing system for a line head having a plurality of heating elements and capable of printing with a plurality of gradation scale values comprising:
- memory means for storing received gradation scale values of pixels for a line to be printed;
- arithmetic means, coupled to said memory means, for determining the number of pixels of the line to be printed for each respective gradation scale value and for determining the number of heating elements to be heated for each respective gradation scale value for the line to be printed based upon the determined number of pixels;
- storage means for storing a plurality of tables for correcting a density variation in a printed line caused by common resistance unevenness;
- and
- control means, coupled to the line head, for retrieving an optimal table for each respective gradation scale value for the line to be printed from said storage means based upon a gradation scale value and the determined number of heating elements to be heated for the respective gradation scale value and for controlling the line head to print the line in accordance with the retrieved optimal tables.
A line printing system for a line head having a plurality of heating elements and capable of printing with a plurality of gradation scale values comprising:
- a memory which stores received gradation scale values of pixels for a line to be printed;
- an arithmetic unit, coupled to said memory, which determines the number of pixels of the line to be printed for each respective gradation scale value and which determines the number of heating elements to be heated for each respective gradation scale value for the line to be printed based upon the determined number of pixels;
- a storage unit which stores a plurality of tables for correcting a density variation in a printed line caused by common resistance unevenness;
- and
- a controller, coupled to the line head, which retrieves an optimal table for each respective gradation scale value for the line to be printed from said storage unit based upon a gradation scale value and the determined number of heating elements to be heated for the respective gradation scale value and for controlling the line head to print the line in accordance with the retrieved optimal tables.
Dependencies are inferred from the claim text.