Abstract: An optocoupler with a light guide defining element is presented. The light guide defining element has at least one cavity configured to define the shape of the light guide formed by a transparent encapsulant encapsulating the optical transmitter and receiver dies. The transparent encapsulant in liquid form may be injected into the cavity prior to a curing process to harden the encapsulant into a light guide with a predetermined shape. The cavity of the light guide element may be defined by a reflective surface having micro-optics formed thereon. A multichannel optocoupler with multiple transmitter and/or receiver dies having such light guide defining element is also presented. The light guide defining element may have a single cavity enveloping all the optical transmitter or receiver dies, or a multiple cavities by having a pair of transmitter and receiver dies inside each cavity.