The present invention addresses the problem of obtaining illumination light having the desired light emission spectrum stably and with simple controls even when using a fluorescent semiconductor light source. A fluorescent semiconductor light source, wherein the green semiconductor light source (36) is configured from an excitation light LED (44) for emitting blue excitation light (LBe) and a green fluorophore (47), which is excited by the blue excitation light (LBe) and emits green fluorescence (LGf). The dichroic filter of the third dichroic mirror (81) of the light path-unifying section (41) has a transmission characteristic such that at least the blue excitation light (LBe) is removed from the light emission spectrum of the mixed light of the blue excitation light (LBe) and the green fluorescence (LGf) emitted by the green semiconductor light source (36) and functions as an excitation light-cutting filter, which cuts the blue excitation light (LBe). The light source device is able to constantly supply illumination light having the desired light emission spectrum without the blue excitation light (LBe) affecting the amount of blue light (LB) from the blue semiconductor light source (35).La présente invention aborde le problème dobtention dune lumière déclairage présentant de manière stable, le spectre démission de lumière souhaité et à laide de commandes simples même lors de lutilisation dune source lumineuse semi-conductrice fluorescente. Linvention concerne une source lumineuse semi-conductrice fluorescente, la source lumineuse semi-conductrice verte (36) étant conçue à partir dune DEL de lumière dexcitation (44) pour émettre de la lumière dexcitation bleue (LBe) et dun fluorophore vert (47) qui est excité par la lumière dexcitation bleue (LBe) et qui émet de la fluorescence verte (LGf). Le filtre dichroïque du troisième miroir dichroïque (81) de la section dunification du trajet lumineux (41) présente une caractéristique de transmission telle quau moins la lum
