Glare and blue light from LED-based lamps have raised great concerns for medical professionals around the world. Addressing them requires accurate quantification of luminous intensity distribution (LID) generated by LEDs. For the first time, we demonstrate why inorganic LED chips including a phosphor coating produce non-uniform luminance, high peak luminance, high glare, and very intense blue spectrum. We explain why flat light-emitting devices generate a 3D Lambertian LID in near-field, and offer a novel formulation of the near-field LID from a finite-size flat-light source. Our analytic formula, extendable for lasers, is very useful for calculating the peak luminance and LID profiles from an LED light source. It reveals that larger LED chips and 2D arrays with higher luminance generate higher peak luminance, higher luminous intensity, and increased glare and can result in consuming unsafe amounts of bright light and harmful blue light when we directly look at high-power LED lamps.
(This article was rejected by OSA and other scientific journals. Rebuttals are also published independently by Khan.)
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