The present invention relates to an optical module or the like having a structure which prevents the efficiency in a sleeve securing operation or optical characteristics from deteriorating and improves adhesion durability. In particular, a resin mold portion including an optical device in the optical module according to the present invention is processed into a shape which can directly irradiate the UV-curable resin introduced between the resin mold portion and the sleeve with ultraviolet rays, and a structure for restricting the flow of the resin changing into a flowing state during the sleeve securing operation or a structure for improving the adhesion durability of the sleeve is provided on at least one of the sleeve side and resin mold portion side.