Organic solid-state lasers are reviewed, with a special emphasis on works
published during the last decade. Referring originally to dyes in solid-state
polymeric matrices, organic lasers also include the rich family of organic
semiconductors, paced by the rapid development of organic light emitting
diodes. Organic lasers are broadly tunable coherent sources are potentially
compact, convenient and manufactured at low-costs. In this review, we describe
the basic photophysics of the materials used as gain media in organic lasers
with a specific look at the distinctive feature of dyes and semiconductors. We
also outline the laser architectures used in state-of-the-art organic lasers
and the performances of these devices with regard to output power, lifetime,
and beam quality. A survey of the recent trends in the field is given,
highlighting the latest developments in terms of wavelength coverage,
wavelength agility, efficiency and compactness, or towards integrated low-cost
sources, with a special focus on the great challenges remaining for achieving
direct electrical pumping. Finally, we discuss the very recent demonstration of
new kinds of organic lasers based on polaritons or surface plasmons, which open
new and very promising routes in the field of organic nanophotonics