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Some functions of machine vision can be very undemanding for
lighting quality of a scene. Especially when using cameras, which can
sufficiently extend the exposure time in poor light without
significant increase of noise in image, we can succeed even with
common room lighting or table lamp. Cheap lighting can be often
handled by fluorescent tubes, which provide intensive and color-stable
light. Fluorescent tubes could be the only rational solution for large
dimensioned lighting devices.
In practice, the prevailing applications are those, which have the
right parameters of lighting, like intensity, color and direction.
Those are the crucial factors for visibility of followed objects in
scene. Here the LED illuminators are used. These illuminators are
characterized by low power consumption and long-term stability of
parameters.
DataLight LED illuminators fulfill high demands. At very pleasant
cost, they can easily solve difficult applications, in which is
necessary to take images automatically in different directions,
intensity and colors of light. DataLight illuminator could be
controlled by camera. Permanently shining illuminators can work even
without camera. After connecting power voltage, it begins to shine by
its maximum brightness.
The advantages of these illuminators are:
Direct control by DataCam cameras. It is possible to connect
up to four illuminating units to a single camera. At permanently
shining units, camera can turn on and off the illuminator and set
the intensity of the light. At flashing units, camera can emit
flashes during exposure time. By regulating brightness and several
illuminating units is possible to, e.g., adjust lighting of
variously distanced surfaces or to highlight single objects in a
scene. It is possible to combine automatically and sequentially
several lighting types of a single scene. Lighting units have solid body from aluminous alloy and
can be equipped by a diffuser of an optional type: It is possible to change the color of light, which can
be: By choosing the color of light is possible to solve, for
example, the suppression of unwelcome surrounding lighting. Camera
could be equipped by colored filter, which transmits the light of a
lighting unit and suppresses the rest of the color spectrum. This
proceeding can significantly increase durability of the application
against undesirable lighting. The choice can be even between narrow, middle wide and wide
emissive angle. The illuminator can be adapted to size and distance
of the scene, especially at reflectors without diffuser. Units can be determined for permanent light or can generate
flashes controlled by camera exposure. By flashes, we can lighten,
for example, moving objects. The influence of undesirable lighting
of a scene can be suppressed by intense flashing light, because then
camera can work with shorter exposure time. Units are powered by contact power sources 12VDC and are
characterized by very low power consumption approximately 4W.
Powering can be twisted among single illuminators and several
illuminating units can be powered by one power source.
DataLight LED lighting units exist in several
versions:
Circular coaxial lighting unit mounted on DataCam cameras
with shining annulus with inner diameter of 45mm and outer diameter
of 65mm 
Circular illuminator DataLight LT-41S in set with
DataCam digital camera Flat lighting units with rectangular LED matrix and shining
area of 60 * 40 mm 
Stand-alone flat illuminator LT-40S Large flat lighting units with rectangular LED matrix and
shining area of 130 * 200 mm Backlight for rear lighting. With these units is possible to
choose only the color of light, illuminators are always equipped
with such diffusers, which provide uniform distribution of
brightness on its surface. 
Backlight with white light LT-81
We can specify permanently shining or flashing variant, type of
diffuser, color and LED emitting angle for almost every type of
illuminator.
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