Patent ID: 8624585

Claim:
A proximity sensor detecting presence or absence of a metal body or a position of the metal body using a magnetic field, said proximity sensor comprising: a light-blocking housing having an elongated cylindrical shape and including a frond end and a rear end in an axial direction; a detecting coil located at the front end within said housing; a circuit board in a shape of a flat plate, said circuit board being provided with a processing circuit electrically connected to said detecting coil and disposed behind said detecting coil so as to extend along the axial direction of said housing; a light emitting device mounted on one of main surfaces of said circuit board and emitting light in accordance with an operation state; and a light-transmitting cylindrical light guide surrounding, along a circumferential direction of said housing, a portion of said circuit board having said light emitting device mounted thereon, said cylindrical light guide guiding outgoing light from said light emitting device to be emitted to outside, said cylindrical light guide including a first light outgoing region causing the light emitted from said light emitting device to pass therethrough and directly emitting the light to outside, a reflective surface reflecting the light emitted from said light emitting device to guide the light through said cylindrical light guide in the circumferential direction, and a second light outgoing region emitting, to outside, the light reflected on said reflective surface and propagated through said cylindrical light guide, wherein said first light outgoing region is provided in a portion of an outer circumferential surface of said cylindrical light guide covering said one of the main surfaces of said circuit board on which said light emitting device is mounted, and wherein said second light outgoing region is provided in a portion of the outer circumferential surface of said cylindrical light guide blocked by said circuit board as seen from said light emitting device.