Organic field-effect transistors (OFETs), which are based on organic semiconducting materials as a channel layer, have been spotlighted because of their potential for futuristic logic devices. However, the charge carrier mobility of OFETs is still limited for the application of logic device applications. In this regard, the study of OFETs has been scattered to a variety of applications that do not need high-charge mobilities. The potential applications include photon-detecting or light-sensing OFETs which seem to be actually viable in that most organic semiconducting materials are able to absorb photons in an energy range between ultraviolet (UV) and infrared (IR). Compared to UV and visible light, the IR range is relatively tricky to detect owing to a small energy level gap leading to a less pronounced photovoltaic effect. This presentation reviews our ongoing efforts for the sensing of IR with a device geometry of OFETs.