| 摘要 |
A projection screen 111 comprises a total reflection prism lens 114 and a lenticular lens 115 provided on the viewer's side of the total reflection prism lens 114. The total reflection prism lens 114 has a plurality of unit prisms 113 on its back surface (the outermost plane of incidence) on which imaging light L is incident. Each unit prism 113 has an apical angle lambda that corresponds to the angle between the plane of incidence 113a and the plane of total reflection 113b, and the apical angles lambda of the unit prisms 113 vary with the position of each unit prism 113 on the screen plane. In particular, the unit prisms 113 have apical angles lambda varying continuously from 30 DEG to 45 DEG so that the apical angles lambda on the side distant from the center O of the concentric circles are greater than the apical angles lambda on the side close to this center O. <IMAGE> |
