Fitted line plot of irradiance recorded with the BM I linear sensor radiometer versus integrating sphere derived irradiance for Type I and Type II LED-LCUs.

High outliers (circled from left to right of the graph) were noted for the Spark SK-L036A, Satelec Supercharged, and Blast Mini LED-LCUs. A similar pattern was noted with the Ledex CM 4000 sensor. These two radiometers were the only ones with relatively narrow linear sensors. When beam profiles for these three units were inspected, it was noteworthy that all three units exhibited centrally located "hot spots" with low areas of light output on the outer regions of the light guide exit faces. Fig 7C and 7D show representative beam profiles for two of these three LCUs.