Photoelectric sensor

A photoelectric sensor comprising:

• a light emitting element configured to project detection light toward a detection region;
• a light receiving element configured to receive the detection light reflected from the detection region;
• a connecting section for light projection to which a light propagation member for light projection optically coupled to the light emitting element is connected;
• a connecting section for light reception to which a light propagation member for light reception optically coupled to the light receiving element is connected;
• a signal generating unit configured to compare a light reception signal generated by the light receiving element and a threshold and generate a detection signal indicating a result of the comparison;
• a second light emitting element for indication which is optically coupled to the connecting section for light projection and projects an indication light in response to the light reception signal;
• and
• a mounting substrate which the second light emitting element for indication and the light emitting element are mounted on or above, and each of the second light emitting element for indication and the light emitting element provided on the mounting substrate being positioned to the connecting section for light projection or one of the second light emitting element for indication and the light emitting element being positioned to the connecting section for light projection via the other.