Vehicle headlight

Abstract

A vehicle headlight can be configured such that the size of the vehicle headlight which includes a semiconductor laser element employed as a light source is reduced. The vehicle headlight can includes: a projection lens disposed on an optical axis extending in a front-to-rear direction of a vehicle body; a light-emitting device including a semiconductor laser element configured to emit a laser beam and a light-transmitting member configured to absorb and convert the wavelength of at least part of the laser beam from the semiconductor laser element; and a first reflection surface configured to reflect the light from the light-emitting device so as to transmit and project forward the resulting light through the projection lens. The vehicle headlight can further include: a light detection unit configured to detect a light beam of a specific color, the light detection unit being disposed between the projection lens and the light-emitting device and below the optical axis; a second reflection surface configured to reflect the light beam from the light-emitting device toward the light detection unit, the second reflection surface being disposed ahead of the front end of the first reflection surface; and a control unit configured to control the semiconductor laser element in accordance with a detection result provided by the light detection unit so that the semiconductor laser element does not emit the laser beam.