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:

  • clear diffuser with surface structure

  • opal diffuser

  • clear front face without diffuser

• It is possible to change the color of light, which can be:

  • white

  • red

  • blue

  • infrared

  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.