Techniques are described for the detection of multiple target species in real-time PCR (polymerase chain reaction). For example, a system is described that includes a data acquisition device and a detection device coupled to the data acquisition device. The detection device includes a rotating disk having a plurality of process chambers having a plurality of species that emit fluorescent light at different wavelengths. The device further includes a plurality of optical modules. Each of the optical modules is optically configured to excite the species and capture fluorescent light emitted by the species at different wavelengths. A fiber optic bundle coupled to the plurality of optical modules conveys the fluorescent light from the multiple optical modules to a single detector.