| 摘要 |
<p>PURPOSE:To make efficient measurement with the decreased quantity of the IR rays to be lost from a measuring region by making measurement between a 1st reflecting means having a light condensing characteristic and the 2nd reflecting means which reflects the light condensed by a projecting lens. CONSTITUTION:The light emitted from a convex lens 8 is made into the collimated beams of light which are projected on paper 3. The light transmitted through the paper 3 includes the rectilinear light and the light deflected by scattering which are stopped down by a convex lens 9 and are reflected by a mirror 10 and a detector 11. The reflected light beams return by tracing the same passage again. On the other hand, the light applied to the detector 11 includes the component which is transmitted by the IR ray from an IR source 4 through the paper 3 and is directly entered from the convex lens and the component which is entered after the reflection between the mirrors 7 and 10 and repeated transmission through the paper 3. The ratio of these components is easily changeable by changing the mounting angle phi' of the detector 11.</p> |
