Patent ID: 11933468
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC F  B | IPC F

Claim 9:
10. A headlight device comprising:
a first optical system that emits first light in a predetermined emission direction, the first optical system having a first optical axis; and
a second optical system on which second light traveling in an incidence direction opposite to the emission direction is incident, the second optical system having a second optical axis, and including a light receiver and a beam splitter,
wherein:
part of the first optical axis coincides with part of the second optical axis in the emission direction,
the beam splitter emits the first light in the emission direction and guides the second light traveling in the incidence direction to the light receiver,
the beam splitter includes a central part, which is arranged on the first optical axis, the central part reflects the first light and transmits part of the second light traveling in the incidence direction and guides the part to the light receiver,
the central part sets a diameter of the second light traveling toward the light receiver through the second optical system to be smaller than a diameter of the second light when entering the second optical system,
the beam splitter further includes a peripheral part that is arranged on an outer side relative to the central part and reflects the first light, reflectance of the peripheral part is higher than reflectance of the central part.