An optical element having a front side and a back side operates in an ambient lit mode and a backlit mode. The optical element includes a diffusely reflecting layer facing the front side for reflecting ambient light. A light absorbing layer faces the back side and is positioned to prevent back light from illuminating the diffusely reflecting layer. A plurality of light transmitting regions extend through the light absorbing layer and the diffusely reflecting layer for permitting back light to pass through in a restricted angular range without illuminating the diffusely reflecting layer.
申请公布号
US7419272(B2)
申请公布日期
2008.09.02
申请号
US20050297615
申请日期
2005.12.08
申请人
3M INNOVATIVE PROPERTIES COMPANY
发明人
SCHENKE KAY-UWE;HITSCHMARIN GUIDO;DIETRICH STEFAN O.;BENNETT ROBERT;HUMPAL PAUL E.;KOTCHICK KEITH M.