Exposure apparatus

In order that an exposure apparatus for a substrate comprising, as a substrate base, a flat material having mutually opposite substrate base surfaces and, on each of the substrate base surfaces of the substrate base, a photosensitive layer in which photochemical processes can be initiated by selective exposure and selective structures can be produced as a result, comprising a machine frame, and at least one exposure unit, is improved in such a way that a substrate having sensitive layers arranged on opposite sides can be exposed as efficiently as possible, it is proposed that a substrate guide is provided on the machine frame, which substrate guide positions the substrate with the substrate surfaces thereof parallel to an exposure guiding area and transversely with respect to the exposure guiding area in a defined manner and guides it movably in an advancing direction running parallel to the exposure guiding area, that for the purpose of exposing the photosensitive layers exposure units arranged on the machine frame in a stationary manner on both sides of the exposure guiding area are provided for selectively exposing in each case one of the photosensitive layers, and that the substrate is movable for the purpose of exposure relative to the exposure units in the advancing direction.