Onychomycosis is the most common nail disorder. The treatment for this type of infection is one of the main difficult ones in clinical practice, due to the fact that the nails are nonvascularized structures, which compromise the penetration of drugs delivered systemically and favor slow nail growth. We present two devices based on light-emitting diode arrays as light sources for the treatment of onychomycosis by photodynamic therapy (PDT). PDT is an emerging technique that uses a photosensitizer (PS) activated by light in the presence of oxygen. The PS absorbs energy from light and transfers it to oxygen, producing reactive oxygen species such as hydroxyl radicals, superoxide, and singlet oxygen which inactivate fungi and bacteria. Our proposal is the use of a portable and secure light source device in patients with onychomycosis. Additional advantages are the low cost involved, the possibility of topical treatment rather than systemic and the simplicity of operation. These advantages are important to ensure the implementation of this technology for the treatment of an impacting health problem.