4 - 15
Thermal Considerations
Care must be taken when designing the Image Engine into any system. Internal
heating of the Image Engine can occur in high duty cycle scanning applications
in several ways. The high visibility aimer dissipates a significant amount of
power as heat. The illumination and aiming LEDs also release heat, and are a
major contributor to thermal increases in high use or in presentation mode.
An increase in temperature around an Image Engine can cause noise levels on
the imager, degrading image quality. The thermal rise can also affect the laser
diode. In a continuous scanning or high use environment, the Image Engine
temperature can rise 15° to 20°C. Under high ambient temperature conditions,
the laser diode is at risk of thermal breakdown and possible failure. The image
quality and decode performance will also degrade.
The Power Control PWM can be used to reduce the effect of the illumination
LEDs on thermal rise, however, this also reduces the intensity of the illumination.
Reducing the intensity of the illumination reduces total power used but can also
reduce the depth of field in low light environments.
Centering
Use Centering to narrow the scanner’s field of view to make sure that when the
scanner is hand-held, it reads only those bar codes intended by the user. For
instance, if multiple codes are placed closely together, centering will insure that
only the desired codes are read. (Centering can be used in conjunction with
Aimer Delay on page 4-13 for the most error-free operation in applications where
multiple codes are spaced closely together. Using the Aimer Delay and
Centering features, the scanner can emulate the operation of older systems,
such as linear laser bar code scanners.)
If a bar code is not touched by a predefined window, it will not be decoded or
output by the scanner. If centering is turned on by scanning Centering On, the
scanner only reads codes that pass through the centering window you specify
using the Top of Centering Window, Bottom of Centering Window, Left, and
Right of Centering Window bar codes.
To Next Page
Loading...
Need help?
General
