Back to results
US 4,549,222 AGranted
Dot matrix printing method and printer therefor
AssigneeIng. C. Olivetti & C., S.p.A.
InventorsGiuseppe Fogaroli, Giuseppe Coli
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeIng. C. Olivetti & C., S.p.A.
InventorsGiuseppe Fogaroli, Giuseppe Coli
Estimating the term…
The method enables images recorded with different definitions to be printed by the same printer, and the information to be printed with maximum print definitions. For this purpose, the print definitions (dots per mm) is a common multiple of the possible recording definitions. The information to be printed is extracted from a signal generator with a frequency corresponding to the recording definition, and is repeated in accordance with the multiple. For example with a print definition of 24 dots/mm defined by a row and column grid L1, L2, etc., C1, C2, etc., a character definition of 8 dots/mm is obtained by printing each dot three times in each row and repeating each row a further two times. The printer, which is therefor suitable for various purposes, for example as a word processor printer and as a facsimile printer, repeatedly prints each dot, along the horizontal and/or along the vertical, for a number of times corresponding to the multiple, to provide a line continuity and an improved image resolution. The printer used may be of electrophotographic type, with the printing element provided by a laser generator.
A dot printer operable for printing an image recorded in accordance with a pair of predetermined definitions associated to a pair of perpendicular directions on the original image, said printer including a printing element conditionable at a control frequency for printing the dots in accordance with a matrix having along at least one of said directions a definition multiple of the corresponding definition by which the original image has been recorded, signal generating means for generating electrical signals corresponding to the bits of the recorded image, signal extracting means conditionable for extracting said signals from said signal generating means in sequence, a pair of frequency generating circuits associated with said directions and arranged for selectively defining in the corresponding direction said multiple, each circuit conditioning said extracting means to extract said signals from said signal generating means with an extraction frequency such that the ratio of said control frequency to said extraction frequency is equal to said multiple, and a pair of frequency dividers associated with said directions and each one controlled by said frequency generating circuit for so conditioning said extracting means, whereby said printing element prints in said directions for each extracted signal a number of dots equal to said multiple so that the images recorded upon being scanned according to one of a plurality of definitions is printed according to said multiple definition.
Dependencies are inferred from the claim text.