A tandem organic light-emitting diode structure, excited electrically in the pulsed domain and confined within a double spatial filter configuration, is observed to emit a low-divergence beam ((DELTA)(theta)(approx=)2.53 mrad, or approx1.1 times the diffraction limit) with a near-Gaussian spatial distribution. The emission originates from the laser dye Coumarin 545 T, which is used as a dopant. Spectral coherence was determined by use of a double-slit interferometer. The interferometric distribution from our device approximates the interferometric pattern obtained from well-known lasers emitting at (lambda)(approx=)540 nm.
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