| 摘要 |
PURPOSE: A projection screen having a multi-short focal distance is provided to make a focal distance of a screen and a focal distance of a short-focus projector coincide, thereby removing a hot-spot phenomenon. CONSTITUTION: A projection screen having a multi-short focal distance includes a surface base (1), a rear base (2), and a transmissive surface (3). The surface base has the convex spherical surface on the pixel surface (D) of 0.1-5m/m unit. The rear base has the convex spherical surface on the pixel surface of 0.1-5m/m unit. The screen includes a focal distance in which the sum of the plus focal distance of the convex spherical surface and the minus focal distance of the concave spherical surface coincides with a projection distance of the short focus projector. |
