Push button switch

A push button switch comprising a push button that may be pushed in, a movable contact that moves together with the push button, and a fixed contact with respect to which the movable contact comes into contact or separates in accordance with an operation of the movable contact, the push button switch comprising:

• a light emitting element that emits light;
• and
• a light receiving element that detects light,
• wherein a light emitting position at which light emitted from the light emitting element is radiated to an outside, and a light receiving position at which light detected by the light receiving element is received from the outside are disposed outward of an edge of the push button in a line of sight viewed in a pushing direction, and
• wherein the light receiving element is disposed is such a way as to detect light that has been emitted from the light emitting element and has been reflected by an object in a detection region set in a space on a side of the push button in an opposite direction to the pushing direction.