| 摘要 |
PURPOSE:To measure the thickness and shape of a plastic optical mold without contact with an object to be measured by utilizing absorption of IR rays. CONSTITUTION:A specified quantity of IR rays generated by an IR emitting element 1 such as an IR emitting diode or IR semiconductor is made into parallel light by a collimator lens 9 and passes through a null lens 3 held by a jig 2 and a plastic optical mold 4 which is an object to be measured. The material of the lens 3 is glass which does not absorb IR rays and has an optically complementary relation with the mold 4. The IR rays attenuated by passing through the mold are detected by an IR detecting element 5 and the quantity of the light is amplified and measured in a signal amplifying and processing part 6 and is recorded by a cord 7. If the object to be measured having a known thickness is preliminarily measured, the thickness of the object to be measured is measurable from the above-described relation and the change in the thickness is also measurable by the moving measurement thereof. |
