| 摘要 |
PURPOSE:To make an optical signal generator small-sized, by providing an external light quantity adusting means on a combiner, relating to a display device for use by an aircraft pilot, etc. CONSTITUTION:In a head-up display device (HUD) used by an aircraft pilot, a light quantity control means of a liquid crystal, an electrochromic element, etc. is provided on a combiner 3 for reflecting a signal light 5 so that a pilot can visually confirm it together with external light. Also, the external light quantity is controlled, detecting the quantity of incident light to a light quantity detector 8, so that small luminance of a signal generated by an optical signal generating part 1 is made enough. |
