A system for focussing a lens on a point light source is provided that includes an opaque member disposed near the lens. The member cast a shadow having a distinguishable orientation in the image of the light source. An image processing device determines the focus condition and range to the point light source from the orientation and size of the shadow.
申请公布号
US4974010(A)
申请公布日期
1990.11.27
申请号
US19890363716
申请日期
1989.06.09
申请人
LC TECHNOLOGIES, INC.
发明人
CLEVELAND, DIXON;CLEVELAND, JAMES H.;NORLOFF, PETER L.;FORSYTHE, JEFFREY A.