User manual

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1.0 INTRODUCTION
1.1 General Description
The OYO Instruments TechSetter thermal imager is a computer to film imagesetter for
graphic applications; it is a high-tech narrow-format and rugged imaging device designed
for office use. It utilizes direct thermal printing technology; with few moving parts and
no liquid chemicals to contend with, it operates efficiently and requires only nominal
maintenance.
1.2 Functional Description
The TechSetter is a raster-scan device that plots information on thermal-sensitive media
by sequentially addressing an array of nibs (dots) along a fixed thermal print head and
incrementally moving the media a fraction of the dot length. Fig. 1 is a block diagram of
the TechSetter. The components include (a) thermal print head and its driver circuitry;
(b) micro-stepper motor and its control circuitry; (c) pressure roller (platen) which is
driven by the micro-stepper motor; (d) media cutter, and (e) interface electronics and
power supplies.
Thermal-sensitive media from the supply roll is fed between the platen and the thermal
print head. The micro-stepper motor turns the platen, moving the media past the print
head in steps of 0.026 mils (0.0006 mm) for 600x600dpi models. Stepping can be
controlled directly by the TechSetter or indirectly by the data source. As the media
moves, the nibs in the thin-film print head are addressed through the interface circuitry
and heated by applying power to produce an array of dots representing graphic data and
alphanumeric characters. Each dot is 1.6 x 2.5 mils (0.04 x 0.06 mm) for 600x600dpi
models. The heated nibs in contact with the thermal-sensitive media develop color
(black) through a thermo-chemical reaction in the media's coating. Plotting and stepping
is repeated until the desired image is produced.
1.3 Media Description
The thermal-sensitive paper used in the TechSetter consists of a base paper and coating of
colorless, non-toxic dye. Some papers with lower sensitivities also employ protective
coatings to improve their handling characteristics. The paper has a bright, smooth
surface, is about 3 mils (0.075 mm) thick. Color (black) is developed to an optical
density of about 0.8 Ortho.
The thermal-sensitive film used in the TechSetter consists of a base polyester, imaging
layer and protective top-coat layer. The film is approximately 5 mils (0.0127 mm) thick.
The imaging layer consists of a silver nitrate that exposes to black when heat is applied.
This reaction results in optical densities of greater than 3.o Ortho and 4.0 UV.