| 摘要 |
PURPOSE: To realize the control of the composition distribution and refractive index distribution and the stabilization of quality with high precision by sprinkling a showered or misty liq. on a porous body obtained by a sol-gel method for a specified time. CONSTITUTION: A columnar porous body 4 obtained by a sol-gel method is fixed to a rod-shaped gel holder 3 provided to the lower part of a stage 2 erected in a closed vessel 1. The porous body 4 is turned on its axis, and the holder 3 is moved in direction of the arrow X. A showered or misty liq. is simultaneously sprayed on the porous body 4 through a soln. feed nozzle 5 hung from a nozzle support 6 fixed to the upper part of the stage 2 for 0.2γ<2> min (γ is the shortest distance between the surface of the porous body 4 and the center of gravity). |
