| 摘要 |
A variable density light transmitting device comprising a first light transmitting layer having a plurality of light polarizing areas with differently oriented transmission axes; a second light transmitting layer overlying said first light transmitting layer and movable relative said first layer while remaining generally parallel to said first layer, said second light transmitting layer having a plurality of light polarizing areas of differently oriented transmission axes of corresponding size and arrangement to said light polarizing areas on said first light transmitting layers said light polarizing areas on said first layer being selectively positionable opposite different ones of said light polarizing areas of said second layer by relative movement of said first layer with respect to said second layers whereby variable density light transmission is provided through said first and second layers by said relative movement. In one embodiment the relative movement is linear, and in another embodiment the relative movement is rotational. |
