| 摘要 |
PURPOSE:To make a titled device compact by placing a light source in the axial direction of a column body in a focal plane containing the first focus of an ellipse, on a condensing block which is formed by a transparent column body whose refractive index is larger than that of the outside, and also whose cross section shape constitutes a part of the ellipse. CONSTITUTION:A condensing block 1 consisting of a transparent body whose refractive index is larger than ''1'' extends as a column body in the direction falling at right angles to the paper surface, and as for its cross section, outside circumferential parts 2, 3 constitute a part of an ellipse, and end parts 4, 5 are linear. The first focus 6 exists on the end part 4, and also a position of the second focus 7 is shown in the figure. The outside of the condensing block is surrounded by a medium whose refractive index is ''1''. A light from a light source 8 placed on the first focus 6 existing on an input end face 4 is totally reflected by the outside circumferential parts 2, 3 of the ellipse, and converged to the second focus 7. When the light source 8 is formed like a light source array extended in the axial direction of the column body of the condensing block 1, a high illumination irradiating area like a straight line, which passes through the second focus 7 and extends in the axial direction is obtained. |
