发明名称 Opaque adapter for overhead projector
摘要 An opaque adapter for an overhead projector uses a hood with clamshell doors to provide generous access to the projector stage during transparency projection and efficient light shielding during opaque projection. The clamshell doors are oriented upon hinges slanted to the vertical so as to rise away from the stage when opened. Spring devices offset the gravitational forces on the doors, allowing rapid motor actuation with very little power. Dual dichroic optics maintain a cool stage despite high light intensity, and internal baffles further increase brightness.
申请公布号 US4930886(A) 申请公布日期 1990.06.05
申请号 US19880281180 申请日期 1988.12.08
申请人 NUMA CORPORATION 发明人 WILLIAMS, RICHARD E.;SLIMAK, LEWIS W.
分类号 G03B21/08;G03B21/132 主分类号 G03B21/08
代理机构 代理人
主权项
地址