Location detection apparatus

A location detection apparatus for detecting an object existing in a space, comprising:

• a light source that generates light having a directivity for detection;
• a light output side reflector that is rotatable and has a reflecting surface, wherein the reflecting surface reflects at least a part of the light from the light source to the space;
• a rotation mechanism that rotates the light output side reflector around a predetermined rotation axis;
• a drive element that drives the rotation mechanism;
• a first light receiving element that receives the light reflected from the object existing in the space;
• a light reception side reflector that reflects the light from the object to the first light receiving element when the object is irradiated with the light reflected from the reflecting surface of the light output side reflector;
• a second light receiving element that receives and detects the light from the light output side reflector, and provides a detection result;
• a light conductor that conducts one of
• (i) the light reflected from the reflecting surface of the light output side reflector and
• (ii) the light transmitted through the reflecting surface of the light output side reflector toward the second light receiving element when rotational position of the light output side reflector becomes a predetermined position;
• and
• a rotational position detector that detects the rotational position of the light output side reflector based on the detection result of the second light receiving element, wherein
• the light output side reflector includes a beam splitter;
• the beam splitter includes a first reflecting portion and a second reflecting portion, the first reflecting portion having the reflecting surface, the second reflecting portion being a portion of the light conductor;
• the reflecting surface of the first reflecting portion reflects the part of the light from the light source so that the light reflected from the first reflecting portion travels in a first direction;
• and
• the second reflecting portion reflects the light transmitted through the reflecting surface of the first reflecting portion, so that the light reflected from the second reflecting portion travels in a second direction different from the first direction.