Bloom on float glass

Bloom is an interference pattern of optical wave caused by the wrinkling surface of the heat treated float glass. The ratio of transmittance of float glass after heat treatment to that before, eta=T-after/T-before, is used to describe the bloom and it is defined as the bloom parameter for the float glass. The bloom parameter is discussed in this paper. The following results were obtained by experiments and calculations: (1) the bloom parameter is a good description of the light or heavy level of the glass bloom. The smaller the parameter, the heavier the glass bloom; (2) the parameter is approximately proportional to the total amount of tin in the glass; (3) it decreases by exponential law as the treatment temperature increases; (4) no definite relation exists between it and the tin concentration on the glass surface.