Optical receptacle, optical module, and method for manufacturing optical module

An optical receptacle configured to be disposed between an optical transmission member and a photoelectric conversion device, the photoelectric conversion device including a photoelectric conversion element and a detection device for monitoring emission light emitted from the photoelectric conversion element which are disposed on a substrate, the optical receptacle being configured to optically couple the photoelectric conversion element and an end surface of the optical transmission member, the optical receptacle comprising:

• a first optical device including a first fitting part disposed in a surface different from a surface opposite to the substrate, the first optical device being disposed on the substrate so as to be opposite to the photoelectric conversion element;
• and
• a second optical device including a second fitting part configured to be fitted to the first fitting part, the second optical device being disposed on the substrate so as to be opposite to the first optical device and the detection device;
• wherein the first optical device includes:
• a first optical surface configured to allow incidence of first emission light emitted from the photoelectric conversion element, or to emit, toward the photoelectric conversion element, reception light that is a part of second emission light that has been emitted from the end surface of the optical transmission member and has passed through an inside of the second optical device and the first optical device, and
• a second optical surface configured to emit the first emission light toward the second optical device, or to allow incidence of the reception light that has passed through the inside of the second optical device,
• wherein the second optical device includes:
• a third optical surface configured to allow incidence of the first emission light that has passed through the inside of the first optical device, or to emit, toward the first optical device, the reception light that has passed through the inside of the second optical device,
• a fourth optical surface configured to emit, toward the end surface of the optical transmission member, signal light that is a part of the first emission light and has passed through the inside of the first optical device and the second optical device, or to allow incidence of the second emission light emitted from the end surface of the optical transmission member, and
• a light separation part disposed on a light path between the third optical surface and the fourth optical surface, and configured to separate the first emission light incident on the third optical surface into monitor light travelling toward the detection device and signal light travelling toward the end surface of the optical transmission member, or to advance, toward the third optical surface side, the reception light that is a part of the second emission light incident on the fourth optical surface, wherein the light separation part includes:
• a plurality of divided reflection surfaces that are surfaces inclined with respect to an optical axis of the first emission light, and
• a plurality of divided transmission surfaces that are surfaces perpendicular to optical axes of the first emission light and the second emission light,
• wherein the plurality of divided reflection surfaces and the plurality of divided transmission surfaces are alternately disposed along an inclination direction of the divided reflection surface,
• wherein the plurality of divided reflection surfaces internally reflect, toward the detection device side, a part of the first emission light as the monitor light, and wherein the plurality of the divided transmission surfaces allow, to pass through the plurality of the divided transmission surfaces toward the fourth optical surface side, a part of the first emission light as the signal light, or to allow, to pass through the plurality of the divided transmission surfaces toward the third optical surface side, a part of the second emission light as the reception light.