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  • Colored Light Selection Guide

    There are many factors to consider when designing a lighting system for your smart camera.

    Choosing the appropriate color (wavelength) of light is one of these factors.  It is also critical to consider ancillary factors such as lighting geometry, pattern, structure, and other elements that may influence the effectiveness of colored lighting for a specific application.

    An Overview of Colored Lighting Options for Smart Cameras

    Color

    White

    Infrared (IR)

    Red

    Green

    Blue

    Ultraviolet (UV)

    Wavelength

    WHI

    850nm - 1050nm

    625nm-660nm

    530nm

    470nm

    365nm - 395nm

    Benefits

    Includes every wavelength of the spectrum

    IR light is invisible, so it is suitable in situations where visible wavelengths disturb workers

    Typically the least expensive; CCD sensitivity; is usually high

      

    High scattering rate

    365nm light can cause materials to flouresce

    Drawbacks

    Difficult to use bandpass filter to avoid interference from ambient light

    Double check camera sensitivity, some CCDs are not sensitive in IR range

    IR light requires special polarization filters, be sure to use IR lens

      

      

    High scattering rate could create noise on an object with many defects

    Be aware of safety precautions in environments where humans are present

    Typical    Applications

    Color camera applications

    For applications requiring that light penetrate through material like plastic  such as plastic; where and object needs to be made to be seen through

    Any

    For inspecting green colored objects such as PCBs or wafers

    For applications requiring higher resolution of minor defects

    For inspecting glue, adhesives, paint, UV ink

    How to use color reflection/absorption to obtain contrast

    Does the part have color?

    • If the wavelength used is the same color as the object,
      the light will be reflected bright in the binary image.
    • If the wavelength used is opposite the color of the object,
      the light will be absorbed and present as dark in the binary image.
    Colored Light Graphic: In-Sight 7000