| Title |
Brightness Uniformity Evaluation of the LED Planar Light Source using a Illuminometer |
| Authors |
Deukhyeon Nam ; Duck Hee Lee |
| DOI |
http://dx.doi.org/10.5207/JIEIE.2016.30.8.011 |
| Keywords |
Brightness Uniformity ; LED Planar Light Source ; Illuminance Meter ; Luminance Meter |
| Abstract |
We used an illuminance meter in order to evaluate brightness uniformity of a LED planar light source inexpensively and compared with the value measured by a luminance meter. We selected two different LED planar light sources: direct-type and edge-type. The measured uniformity of edge-type is more than 0.95 irrespective of the aperture size. However, the uniformity of direct-type LED source is measured differently for aperture size. Since the uniformity of direct-type is affected by the pixel size, the pixel size should be considered in evaluating uniformity. Both the luminance meter and the illuminance meter(combined the barrel and the aperture) showed similar pattern in uniformity and the standard deviation. By improving the aperture and the barrel, the illuminance meter can measure brightness uniformity with to the luminance meter at low cost. |