| 摘要 |
PURPOSE:To prevent the excessive rise in the temp. of an original surface and to decrease the loss in the quantity of light of an illuminating system by installing a cold mirror in a part of plural pieces of luminous flux courses in such a way that the light reflected by the mirror directs toward the original surface. CONSTITUTION:The luminous flux which is emitted from a light source 23 and is reflected by the 1st reflecting mirror 21 converts to the point P below contact glass 2, and the luminous flux reflected by the 2nd reflecting mirror 22 irradiates the original 3 on the glass 2. Since a plane cold mirror 24 is installed in the route for the reflected luminous flux of the mirror 21 in such a way that the light reflected thereby directs toward the original 3, only the visible rays of roughly a 350-750nm wavelength range reflects and irradiate the original surface. Since IR rays transmit through the mirror 24 and advance toward the point P, the deficiency in the quantity of light is prevented and overheating of the original is avoided. |
