Universal Laser Systems ULS-25PS, Operation Manual

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graphics software. Some basic functions such as cropping, scaling, or mirroring might
be possible but it is usually necessary to use an image processing software to perform a
dot by dot editing or rotation of the bitmap.
Monochrome bitmaps are engraved in the same manner as black filled text. The black
area will turn the laser on and the white area turns the laser off. In order to engrave a
photograph however, a halftone pattern must be created. A halftone is a series of dots
arranged in a specific pattern. By varying the size and intensity of these dots, shading
can be simulated in a process that is similar to that used to generate newspaper
photographs. Sometimes this is referred to as setting the screen for printing. Usually,
imaging software gives the choice of using different halftone patterns including
frequency of lines per inch and pattern angles. The size of the dots decreases as the
line frequency increases. Experiment to see which pattern looks the best. Big dots look
good on some materials and small dots look better on others. If it is not possible to
assign a halftone pattern in the imaging or graphic software, the ULS Printer Driver will
automatically default to a predetermined pattern based on the Resolution setting in the
driver.
RESOLUTION ANGLE SHAPE LINES PER INCH
1000 45 DEGREES ROUND 180
500 45 DEGREES ROUND 90
333 45 DEGREES ROUND 60
250 45 DEGREES ROUND 45
200 45 DEGREES ROUND 36
Bitmap images cannot be cut by the laser system only engraved. The only way to have
the laser system cut out a bitmap is to first convert it to a vector file format such as an
EPS. Raster to vector conversion programs are available that trace the bitmap (this
only works well with monochrome bitmaps) and creates a separate EPS vector file.
These EPS files can then be imported into the graphics program and printed out from
there. Since tracing programs have many adjustments, some practice with them is
necessary to produce desirable results.
Postscript Files
The laser system does not support Encapsulated Post Script (EPS) printing directly.
EPS files can only be edited and printed if they are first imported into a graphics
program. However, since EPS files do support engraving and cutting objects, they are
therefore useful for transferring artwork from one graphics program to another. Once an
EPS file has been imported into a graphics program, the objects can be outlined,
stretched, rotated, mirrored, filled with different colors, or anything else desired. Be
careful when using EPS files in layout software as opposed to true graphics software.
Layout software may allow the placement of EPS files in the artwork but may not
actually import and convert the EPS file to a useful format for the ULS Printer Driver.
The laser system is not a postscript device. This means that postscript fills, postscript
textures, and postscript fonts will not be able to print to the laser system.
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