Vehicle headlight device

A vehicle headlight device used for a vehicle, comprising

• a first lamp that includes:
• a first light source that emits a ray;
• an optical system that has a first wedge prism and a second wedge prism for receiving, deflecting, and projecting the ray from the first light source;
• a rolling mechanism that rotates the first wedge prism about a rotation axis;
• and
• a control circuit that controls the rolling mechanism so as to rotate the first wedge prism, wherein
• the first wedge prism has a first refractive surface perpendicular to the rotation axis and a second refractive surface tilted with respect to the first refractive surface, the first wedge prism having an end at which a distance between the first refractive surface and the second refractive surface is smallest;
• the second wedge prism has a third refractive surface perpendicular to the rotation axis and a fourth refractive surface tilted with respect to the third refractive surface;
• an optical axis of the first light source passes through the first refractive surface and the second refractive surface of the first wedge prism;
• the first refractive surface and the second refractive surface of the first wedge prism are flat surfaces;
• the first refractive surface and the third refractive surface are disposed so as to face each other;
• and
• the control circuit controls the rolling mechanism so that the end of the first wedge prism is located on an opposite side of a road surface with respect to the optical axis of the first light source.