Head-up display

A head-up display for displaying picture information viewed as a virtual image from a view point, said virtual image is formed by reflecting the picture information projected from an optical unit, the optical unit comprising a display device which emits light of a plurality of wavelength-bands for displaying said picture information and a prism which is located on a light path between said display device and said view point, further comprising an optical element which changes the light path between said display device and said prism, wherein;

• the position of each of lights of a plurality of wavelength-bands in said virtual images of said display device formed by said optical element is made different from another in the virtual image of said display device formed by said optical element by a distance d expressed as follows,
• d=L1×|φi1−φi2|+L2×|φo1−φo2|×(cos φi1/cos φo1)
• and further
• |φo1−φo2| is within a permissible range;
• where L1 denotes the length of the light path between said virtual image of said display device formed by said optical element and said prism, L2 denotes the length of the light path between said prism and said view point, φi1 denotes the angle of incidence at which a light of a center wavelength λ1 in said first wavelength-band incidents onto said prism, φo1 denotes the angle of emergence at which the light emerges from said prism, φi2 denotes the angle of incidence at which a light having a center wavelength λ2 in said second wavelength-band incidents onto said prism, and φo2 denotes the angle of emergence at which the light emerges from said prism.

A head-up display for displaying picture information viewed as a virtual image from a view point, said virtual image is formed by reflecting the picture information projected from an optical unit, the optical unit comprising a plurality of display devices which emits light of a plurality of wavelength-bands, an optical element which synthesizes lights emitted from said display devices, and a prism which is located on a light path between said display device and said view point, for displaying said picture information, wherein;

• the position of each of said virtual images of said a plurality of display devices formed by said optical element is made different from each other by a distance d expressed as follows,
• d=L1×|φi1−φi2|+L2×|φo1−φo2|×(cos φi1/cos φo1)
• and further
• |φo1−φo2| is within a permissible range;
• where L1 denotes the length of the light path between each virtual image of said plurality of display devices formed by said optical element and said prism, L2 denotes the length of the light path between said prism and said view point, φi1 denotes the angle of incidence at which a light of a center wavelength λ1 in said first wavelength-band incidents onto said prism, φo1 denotes the angle of emergence at which the light emerges from said prism, φi2 denotes the angle of incidence at which a light having a center wavelength λ2 in said second wavelength-band incidents onto said prism, and φo2 denotes the angle of emergence at which the light emerges from said prism.

A head-up display for displaying picture information viewed as a virtual image from a view point, said virtual image formed by reflecting the picture information projected from an optical unit, the optical unit comprising a display device which emits light of a wavelength-band of a center wavelength λ and a half width Δλ plurality of wavelength-bands and a prism which is located on a light path between said display device and said view point;

• wherein,
• when the length of the light path between said display device and said prism is L1, the length of the light path between said prism and said view point is L2, the angle of incidence at which a light of a wavelength λ3=λ−Δλ/2 incidents onto said prism is φi3, the angle of emergence at which the light emerges from said prism is φo3, the angle of incidence at which a light a wavelength λ4=λ+Δλ/2 incidents onto said prism is φi4, and the angle of emergence at which the light emerges from said prism is φo4, a difference Δφ expressed as follows
• Δφ=|φo4−φo3|=(L1/L2)×(cos φo3/cos φi3)×|i4−φi3|
• is within a predetermined permissible range.

A signal generator for generating signal to control each of pixels of a display device in a head-up display for displaying picture information viewed as a virtual image from a view point, said virtual image is formed by reflecting the picture information projected from an optical unit, said optical unit comprises said display device which emits light of a plurality of wavelength-bands for displaying said picture information and a prism which is located on a light path between said display device and said view point, wherein;

• generating signal to make different the position of the first pixel at which emits light of a first wavelength-band among said a plurality of wavelength-bands and the position of the second pixel which emits light of a second wavelength-band among said a plurality of wavelength-bands from each other on said display device by a distance d expressed as follows,
• d=L1×|φi1−φi2|+L2×|φo1−φo2|×(cos φi1/cos φo1)
• and further
• |φo1−φo2| is within a permissible range;
• where L1 denotes the length of the light path between said display device and said prism, L2 denotes the length of the light path between said prism and said view point, φi1 denotes the angle of incidence at which a light of a center wavelength λ1 in said first wavelength-band incidents onto said prism, φo1 denotes the angle of emergence at which the light emerges from said prism, φi2 denotes the angle of incidence at which a light having a center wavelength λ2 in said second wavelength-band incidents onto said prism, and φo2 denotes the angle of emergence at which the light emerges from said prism.