| 摘要 |
<p>This invention is directed to the production of glasses exhibiting an annealing point between 290 DEG -325 DEG C, an index of refraction between 1.57-1.66, a linear coefficient of thermal expansion (25 DEG -300 DEG C) between 130-160X10<-><7>/ DEG C, and a weight loss after exposure to boiling water for six hours no greater than 0.1% consisting essentially, expressed in terms of mole percent on the oxide basis, of <TABLE> with the proviso that, in the presence of SnO and/or Bi2O3, Ag2O will be essentially absent.</p> |
