| 摘要 |
PURPOSE: To uniformly make the display of a head up type display device brightened. CONSTITUTION: On the front side of the parabolic mirror 1 having the focal distance (f), the halogen lamp 2 is arranged in the position that satisfies the next relation when assuming the distance between the filament 3 and the optical axis center of the parabolic mirror 1 as L, L>(f). The parabolic mirror 1 is provided with the diffusion area applied with the luminous flux diffusion process such as the surface roughening so as to prevent the occurrence of the light collecting part (hot spot) in the vicinity of the center of the display area of the transmission type liquid crystal display element 7 by the reflected luminous flux. Thus, a part of the luminous flux made to enter the parabolic mirror 1 is diffuse reflected in the diffusion area and the remainder is convergently reflected. The luminous flux convergently reflected is reflected by the planar reflection mirror 5, projected on the transmission type liquid crystal display element 7 through the diffusion plate 6, reflected by combiner 9 of the windshield 8 and made to enter the eye 10 of the driver, and then the information is displayed as the virtual image 11 by overlapping the foreground 12. |
