The Far-Field Optical Distribution Profiles and Properties of a Planar White Organic Light-Emitting Diode

摘要

The far-field optical distribution characteristics of a planar white organic light-emitting diode (WOLED) source with 10x10mm2 emissive area were experimentally investigated and compared to that of a near point-source white light-emitting diode (WLED) as control by using an automatic 2-axis optical measuring system in hemi-spherical space. WOLED has become a potential planar lighting source due to its single device structure consisted of multiple organic layers sandwiched by cathode and anode electrodes on glass substrate. The far-field optical distribution profiles and characteristics of a planar lighting source are crucial for optical design work in specific application. The far-field optical distribution characteristics of a planar WOLED source is expected to be unique and different compared to that of a near point source WLED. Our experimental result indicates that the far-field optical distribution function measured from near point-source WLED is close to that predicted by an ideal Lambertian source. The far-field optical distribution function measured from the planar WOLED source with 10x10 mm2 emissive area reveals slightly different characteristics around normal direction from that of the near point-source WLED.