Fastening member and optical receptacle module

An optical receptacle module comprising:

• an optical fiber connector including
• a supporting member supporting an optical fiber, and
• a flange part spreading outward in a radial direction;
• an optical receptacle including
• a laser package,
• a holding member holding the laser package, and
• a fiber holding member disposed on an end portion of the holding member and including an outer lateral surface defining a recess;
• and
• a fastening member removably attached to the optical fiber connector and the optical receptacle to fasten the optical fiber connector and the optical receptacle together, the fastening member including
• a base portion defining a slit having a width smaller than a diameter of the flange part of the optical fiber connector and greater than a diameter of the supporting member of the optical fiber connector such that the supporting member of the optical fiber connector is inserted into the slit and a first surface of the flange part is pressed against the base portion, and
• an engaging portion extending from the base portion perpendicularly to the base portion, and including a spring portion at a tip portion of the engaging portion with the spring portion abutting on the recess of the fiber holding member of the optical receptacle to fasten the fastening member to the optical receptacle.