In various examples, an installation is provided for optically examining surface regions of objects, in particular of painted vehicle bodies, having a test light apparatus for irradiating an object, which is situated in a test region of the installation, with test light and/or for producing a test pattern on the surface region, wherein the test light apparatus has a light-emitting system having a plurality of light-emitting units for emitting test light into the test region, wherein the light-emitting units have a transparent cover with respect to the test region. An operator apparatus is arranged, as viewed from the test region, behind the transparent cover and is set up such that the operator apparatus can be operated by touching at least one section of the cover or/and by approaching such a section. A light-emitting system for such an installation and to a test light module for assembling such an installation are provided.