TOPTICA offers different sets of optomechanics, designed for the most common beam-path configurations. For transmission-mode experiments, three rail-based assemblies produce a collimated terahertz beam (2-mirror setups), or an additional focus (4-mirror setup). For applications that require a reflection geometry, a compact reflection head generates a focus at the location of the sample. The optomechanics are compatible with photoconductive antennas for both frequency-domain and time-domain applications.