Lightpipe design

According to Breault Research Organization, any off-highway instrument or control that needs illumination is a candidate for a lightpipe to take light from where it is generated to where it is needed.

In the past, the lighting of instrument panels and controls was done with direct illumination. An incandescent light bulb placed in front of instruments or behind the control directly illuminated the area of interest. This works, but the illumination is not very uniform. There has to be plenty of empty space between the bulb and the working area to avoid blocking the light.

To complicate matters, equipment manufacturers want to cram more electronics into smaller spaces for lower cost, so there is a need to take light from a small number of lower-power sources on a circuit board and move it around corners to the illuminated areas. Something is needed that takes light from a remote location, feeds it directly to the area where it is necessary, and uniformly distributes it over one or more areas of interest. The device has to be low cost, robust, and able to work in confined spaces.