Back to results
US 3,947,853 AGranted
Subscripting, superscripting, and character height compression in ink jet printing apparatus
AssigneeInternational Business Machines Corporation
InventorsClifford M. Denny, Hugh E. Naylor, III, Thomas H. Williams
Life of this patent
Estimating the term…
Abstract
Techniques are described for producing superscripts (half indexing), subscripts, and character height reduction for an ink jet printer.
Claims12
An ink jet printing apparatus for characters along a common base line and of normal height, superscript characters, subscript characters, and compressed characters, on a record medium, and wherein during printing of normal characters, successive drops are separated by a predetermined inter-drop spacing at said record medium established by predetermined inter-drop charge increments, comprising:
- means for forming and propelling a stream of ink drops toward said record medium;
- charging means operable to variably charge said drops in said stream, and constant deflection means for deflecting said drops in accordance with the charge on said drops in order to form on said record medium at least a line of characters having a normal height range, said characters normally being printed so that they are positioned along a normal common base line and said characters generally extending above said common base line, but some of said characters also normally subtending below said base line each of said characters comprising a series of vertical columns of drops serving to form said characters within a predetermined normal character height range;
- driving means for applying a predetermined range of potentials to said charging means in order to deflect drops in said stream from a lower extremity of said normal character height range to an upper extremity of said normal character height range;
- supplementary potential means for superimposing a supplementary deflection potential to said charging means in order to establish a different character base line level and thereby print certain characters along a base line that differs from said normal character base line;
- compression means interconnected with said supplementary potential means to establish a smaller inter-drop spacing between successive drops directed to said record medium by reducing said inter-drop charge increments whereby each vertical column of drops occupies a shorter range of character height, thereby achieving compression of characters during printing.
2 more elements
An ink jet printing apparatus for printing characters along a common base line and of normal height, superscript characters, on a record medium, comprising:
- means for forming and propelling a stream of ink drops toward said record medium;
- charging means operable to charge said drops in said stream, and deflection means for deflecting said drops in accordance with the charge on said drops in order to form on said record medium at least a line of characters having a normal height range, said characters normally being printed so that they are positioned along a normal common base line and said characters generally extending above said common base line, but some of said characters also normally subtending below said base line each of said characters comprising a series of vertical columns of drops serving to form said characters within a predetermined normal character height range;
- driving means for applying a predetermined range of potentials to said charging means in order to deflect drops in said stream from a lower extremity of said normal character height range to an upper extremity of said normal character height range;
- supplementary potential means for superimposing a supplementary deflection potential to said charging means in order to establish a different character base line level and thereby print certain characters along a base line that differs from said normal character base line;
- a driving circuit incorporated in said driving means for producing a range of charging potentials from a base line reference level during printing of characters;
- reference voltage switching means interconnected with said driving means for switching the base line reference level of said charging potentials during printing of characters other than said normal characters.
3 more elements
An ink jet printing apparatus for printing characters on a record medium, comprising:
- an ink drop source, said ink drop source forming and propelling a stream of ink drops toward said record medium;
- charging means positioned along the path of travel of said ink drop stream for variably charging selected drops in said stream in accordance with intelligence signals;
- deflection means interconnected with said ink drop source and operable to deflect drops from said stream onto said record medium within a predetermined normal range of character height from a lower extremity to an upper extremity of said normal range and each character normally being printed along a normal character base line;
- character generating means including at least a first analog switch means interconnected with said charging means to form on said record medium at least a line of said characters having a normal range of character height along said normal character base line;
- and
- supplementary means including at least a second analog switch means interconnected with said character generating means and operable during print operations to control said charging means to selectively establish a character base line position on said record medium that differs from said normal character base line in order to print characters above or below said normal character base line.
3 more elements
Dependencies are inferred from the claim text.