PRODUCTION OF LIGHT DIVERGENCE ELEMENT MADE OF GLASS

PURPOSE:To produce the light divergence element useful for photoirradiation into a soln. in photochemical reaction, etc. CONSTITUTION:A bar-shaped body 1 is formed of a glass material which can be phase split by heating. This body is heat treated by applying a temp. gradient of the temp. lower in the upper part and higher in the lower part to cause the phase splitting of the glass body in a heating furnace 2 of a temp. gradient type. Irregular reflections take place in the glass body and light is diffused to the outside when light is made incident on the resulted element from its end face. The more irregular reflections the nearer the exit face take place as a result of the gradual increase in the phase splitting density toward the exit surface when the light incidence is executed from the end face on the low temp. side of the above-mentioned treatment. The element having the higher uniformity of light diffusion in the longitudinal direction of the element than the uniformity of the light divergence obtainable with the conventional elements with which the much light is already emitted in the part near the incident end face is thus obtd.