Antenna-coupled optical detectors, also named as optical antennas, are being developed as detection devices with micro- and nano-scale features for their use in the millimetre, infrared, and visible spectral range. They are optical components that couple the electromagnetic radiation in the visible and infrared wavelengths in the same way that radioelectric antennas do at the corresponding wavelengths. Optical antennas show polarization dependence, tuneability, and rapid time of response. They also cann be cosndiered as point detectors and directionally sensitive elements. So far, these detectors have been operated in the mid-infrared with positive results in the visible. The measurement and characterization of optical antennas requires the use of an experimental set-up with nanometric resolution. On the other hand, a computational simulation of the interaction between the material structures and the incoming electromagnetic radiation is needed to explore alternative designs of practical devices. In this contribution we will present the concept of optical and infrared antennas, and some experimental results of their performance, along with the experimental set-up arranged for their characterization in the visible.