Group of optical sensors (S) for a weft feeder, in particular for weaving looms, of the type in which one or more pairs of emitting sensors (E) and SMT-type reception (R) sensors welded on a card printed circuit (8) are arranged on a part of the weft feeder (C) that extends laterally to the drum (T) of the weft feeder in which the wefts of the weft thread are wound, so that they form paths of outflow of optical radiation, from each of said emitting sensors (E) to a reflection surface (9) provided on said drum (T) and return paths of optical radiation, from said reflection surface (9) to the sensors corresponding reception (R), for the detection of the presence / absence of a wire that crosses said paths, characterized in that said optical sensors (E, R) have the optical axis parallel to the plane of said card (8) and why additionally comprises a prime r group of total reflection mirrors (V), one for each pair of sending / receiving sensors (E, R), inclined so that they deflect an optical radiation parallel to the plane of the card (8) in a plane perpendicular to or inclined with respect to it； and a second group of partial reflection mirrors (H), one for each pair of sending / receiving sensors (E, R), inclined so as to partially deflect an optical radiation, keeping it in a plane parallel to the plane in which it place the card (8).Grupo de sensores ópticos (S) para un alimentador de trama, en particular para telares tejedores, del tipo en el que uno o más pares de sensores emisores (E) y de sensores de recepción (R) de tipo SMT soldados sobre una tarjeta de circuito impreso (8) se disponen sobre una parte del alimentador de trama (C) que se extiende lateralmente hasta el tambor (T) del alimentador de trama en el que las bobinas del hilo de trama se enrollan, de modo que forman unos trayectos de ida de radiación óptica, desde cada uno de dichos sensores emisores (E) a una superficie de reflexión (9) provista sobre dicho tambor (T) y unos trayectos de vuelta de radi
