To secure an optical lens over an optoelectronic transmitter or receiver, it is proposed to use a UV-initiated or photoinitiated, cationically curing epoxy resin, by means of which the bonded joint can be set and thereby fixed in a few seconds. Also proposed, for use as adhesives, are resin compositions that can be applied as liquids, are optically matched, and are optimized for durable, reliable use in optoelectronic components and for the large-scale manufacture thereof.