Patent ID: 6292305
Filing Date: 2001-09-18
Classification: G02B

Abstract:
A virtual screen display apparatus comprising:a display arranged to generate display information and having an effective diagonal length DLC;an optical projecting element arranged to receive the display information from the display and to project and form an image, the optical projecting element having an effective F number which is defined by Fe=S1/PuD wherein S1 is a distance between the display and a principal point of the optical projecting element and PuD is a diameter of an exit pupil of the optical projecting element; anda field optical element arranged to form an in-space image in a position of a virtual screen and to direct a divergent light flux from the virtual screen to a view region where the image is viewable to an observer; whereina diameter of a range in which the image is viewable to the observer in the view region is ERD and a diagonal length of the virtual screen is VSD and a distance between the virtual screen and the view region is VSP, and the following equation is satisfied:VSD/VSP=DLC/(ERD.times.Fe).