Light source device and exposure device

A light source device using a plurality of light sources of different wavelengths is provided, and the light source device needs not be strictly arranged in a predetermined arrangement. A plurality of LD modules 1 and 2 are respectively provided with one LD (lasers Diode) and a condenser lens, and emit lasers of different wavelengths. LDs of the LD module 1 and 2 are controlled by a control unit 99 for lighting, non-lighting and the output (illuminance). Emitted light of three LD modules 1 and one LD module 2 are input to a first fiber bundle part b1 and is gathered to a second optical fiber 7 by means of four first optical fibers 5 and a first connector 6. Three second optical fibers are led to a second fiber bundle part b2, and outgoing end sides are bundled according to array patterns corresponding to the shapes of the light irradiation areas of DMDs 56 in an exposure head 18, are connected to a third optical fiber 9 and are connected to an incident light system 40 via a second connector 10, with leading a laser beam to the exposure head 18 of an exposure device B.