Head-up display device for the display of data aboard automobiles

In an automobile, a head-up display device for displaying data on the windshield of the automobile, said display device comprising:

• image forming means for generating visual information transmitted along a first optical path that extends transversely of the vehicle substantially parallel to the lengthwise dimension of the windshield;
• a first optical refractive element situated in said first optical path so as to refract the visual information generated by said image forming means;
• a reflector having a nil optical power situated in said first optical path downstream of said first optical refractive element with respect to the direction in which the visual information is transmitted in the device so as to receive the visual information refracted by said first optical refractive element, said reflector oriented at substantially 45.degree. to said first optical path so as to reflect visual information impinging thereon along a second optical path that subtends an angle of approximately 90.degree. with said first optical path;
• a second optical refractive element situated in said second optical path so as to refract the visual information reflected by said reflector;
• and said reflector being so oriented relative to the windshield of the automobile that said second optical path intersects said windshield at such an angle and location that visual information traveling along said second optical path and refracted by said second optical refractive element reflects at the inner surface of said windshield within the field of vision of a driver whereby the driver can concurrently observe at the surface of the windshield a combination of the panorama in front of the automobile and the visual information generated by said image forming means;
• a structure fixing said image forming means, said first optical refractive element and said reflector to one another so as to together constitute an integrated unit, said structure including a tubular structure to which said image forming means and said first optical refractive element are mounted, and a shaft extending from and parallel to said tubular element and supporting said reflector thereon at an angle of substantially 45.degree. relative to the longitudinal axis of the shaft, said tubular structure having a longitudinal axis coincident with said first optical path;
• and a seat fixed relative to the automobile and supporting said tubular element for rotation about the longitudinal axis thereof wherein said unit is rotatably supported in the device about an axis coincident with said first optical path such that the location of the visual image at the surface of the windshield is adjustable by rotating said unit.