Ink jet printing using horizontal interlacing

DETAILED DESCRIPTION What is claimed is: 1.
A method of printing on an image-receiving surface using an oscillating bar ink jet printer, which comprises: (a) advancing said image-receiving surface at a substantially constant rate in a first direction, (b) oscillating said bar in a direction substantially at a right angle to said first direction, (c) expelling droplets from the oscillating bar as it moves from left to right to form a first row of droplets on said image-receiving surface, (d) expelling droplets from the oscillating bar as it moves from right to left to form a second row of droplets, (e) repeating steps (c) and (d) at least once, wherein the rows of droplets formed during oscillating bar movement from left to right form a first set of columns, and the rows of droplets formed during oscillating bar movement from right to left form a second set of columns and wherein said first and said second sets of columns are interlaced on said image-receiving surface in a direction substantially at a right angle to said first direction.




Description:
The invention relates to an oscillating bar drop-on-demand ink jet printer where printing occurs while the bar is moving bidirectionally.
When using an oscillating bar printer, the placement of drops on the record-receiving surface is affected by the timing of the droplet ejection and the velocity of the record-receiving surface.
Where the oscillating bar is oscillated in a direction perpendicular to the movement of the record-receiving surface, a sine wave trace results as is well known (see, for example, U.
S.
Pat.
No.
4,379,300 issued Apr.
5, 1983, to Kenneth H.
Fischbeck).
A sine wave trace is not normally desirable for the production of printed matter.
To eliminate the sine wave trace, it is possible to use intermittent motion of the record-receiving surface and print only when the record-receiving surface is motionless.
It is also well known that in a printer design, the use of constant record-receiving surface motion results in a printer having reduced weight, lower power requirements and less noise as compared to a printer using intermittent or stepped movement of the record-receiving surface