Datalogic PowerScan PD8590-DPM, Руководство пользователя

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POWERSCAN D8590 User’s Manual
3-7
Basic Operations
Illumination System
The POWERSCAN D8590 ensures reliable decoding of the toughest direct part marks.
Through an advanced combination of low angle (dark field) and multi-colored dome (bright
field) illumination techniques, the imager provides even illumination of flat, shiny surfaces,
enhancing embossed features, or differentiating features on curved surfaces.
Dome Illumination
Low Angle Illumination
Anti-Reflective Coated Window
Low Angle (Dark Field) Illumination
The low angle illumination zone provides what is called “dark field” illumination, ideal for
very low-contrast marks such as laser-embossed or engraved marks. This zone is useful
on both specular and non-specular surfaces and emphasizes surface texture. The optimum
lighting angle for most marks is 30 degrees, which occurs when the imager is approximately
0.25” away from the target mark. This illumination zone actually directs light inward at an
angle, which varies with the actual working distance and provides a good source of low
angle illumination from contact (5 degrees) to about 0.5 inch (45 degrees). Beyond this
working distance for low angle illumination the illumination zone converts to a general purpose
illuminator due to a portion of the illumination passing straight through the prism. This can
be useful in providing “bright field” illumination. This zone was designed for reading larger
marks such as 1D symbols at longer working distances.
Low Angle
Illumination
Zone 1
(Contact to
0.5”)
Low Angle
Illumination
Zone 2 (0.5”
and greater)