| 摘要 |
PURPOSE: To effectively reduce flare incident from the outside of a vehicle by using a hologram as a combiner for diffracting light toward an observer in a vehicle with low diffraction efficiency for S-polarized light and high diffraction efficiency for P-polarized light. CONSTITUTION: Regarding a head-up display using a hologram as a combiner 2 built into the windshield or the like of a vehicle, a display source is provided at the lower position of a windshield 47. This display source emits information to be indicated as light 26 after the passage thereof through a display body 5, using light reaching from a light source 46 via a lens system 44. Then, the light 26 is irradiated to the combiner 2 and diffracted for recognition by a driver. In this case, a hologram with high diffraction efficiency for P-polarized light and low diffraction efficiency for S-polarized light is used, or the hologram is a combined body made of a transmissive hologram 10 diffracting only the S-polarized light without any diffraction of the P-polarized light, and a reflective hologram 21. |
