The present invention relates to a light emitting diode, LED, light source that may be arranged for retrofitting into a luminaire employing an incandescent light source. The light source comprises a light guide into which light from one or more LEDs in a light unit arranged at one end of the light guide is injected, and a reflector having a reflecting surface arranged at the other end of the light guide and facing towards the light guide capable of reflecting light incident on the reflecting surface. According to the present invention, the reflector comprises at least one transmitting portion being arranged such that at least a portion of light incident on the at least one transmitting portion is transmitted through the reflector, for example a through hole extending along an axis, allowing for an almost viewing angle independent light intensity of the light source.