摘要 |
<p>A reflection-type optical focusing apparatus comprising an optical focusing system including at least two 4th-degree surface reflectors with their revolving symmetric axis formed by a line connecting the position of a point source and the point source focusing position, said reflectors being used in combination so that the light emitted from a point source placed at the point source position is focused to form a virtual point source at the point source focusing position, and a 4th-degree surface reflector with its cross-section, on a plane including the revolving symmetric axis, forming a part of an ellipse with its major axis having a certain inclination with respect to the revolving symmetric axis, said virtual point source being located at one focal point of the ellipse so that a light image in the shape of an arc band is obtained.</p> |