Manufacture of concave lens

Abstract

Abstract PURPOSE:To easily and exactly manufacture a concave lens having a desired curvature radius by a method in which an appropriate number of releasable spheres are buried in a molten lens material and then taken out of the molten lens material. CONSTITUTION:An appropriate number of true spheres 6 made of a removable material (e.g., tungsten, graphite, etc.) having a melting point higher than a lens material 5 composed of a crystalline material, e.g., ruby, sapphire, etc. are supported on a vertically movable plate 7, and Al2O3 powder is covered on the spheres 6 and melted by oxyhydrogen flame 9 to cover the spheres 6. In other words, molten Al2O3 to be crystallized and buried with the spheres 6 is deposited and covered on the spheres 6. The spheres 6 buried in the crystalline Al2O3 are finally taken out.

Inventors

• 👤 Masaki Watanabe
• 👤 正樹 渡辺

Bibliographic Details