| 摘要 |
PURPOSE:To enable stable measurement of a temperature response to changes in the atmosphere inside a furnace such as variations in the refractive index of a medium, by employing a solid lens in which the incident surface is a spherical one with a temperature measuring point as the center while the emitting surface is a spherical one with a focusing point as the center, as optical system. CONSTITUTION:An incident surface of a lens 1 is spherical one with the radius r1 and with a temperature measuring point 2 as the center while an emitting surface is spherical one with the radius r2 and with a focusing point 3 as the center. A part 4 with a high refractive index is provided like a convex lens in the lens 1 to include a focusing action as convex lens as a whole. Because of such a shape of the incident surface and emitting surface, an incident light beam entering a lens and emitted light beam conversing on the focus point leaving a lens are both vertically to the incident surface and the emitting surface respectively and hence, there is no refraction caused in the incident surface and the emitting surface. Therefore, changes in the refractive index medium causes no effect thereby enabling stable temperature measurement in no way depending on the atmospheric temperature and pressure. |
