METHODS FOR FORMING GLASS ELLIPTICAL AND SPHERICAL SHELL MIRROR BLANKS

摘要

A method of producing glass focusing mirror blanks comprises providing a glass sheet, heating the glass sheet sufficiently to allow permanent deformation and reforming the glass sheet into an array of glass shell structures by either (1) pressing the sheet or (2) vacuum or differential-pressure forming the sheet. Either (1) the step of pressing is performed using a positive mold surface comprising an array of protrusions pressed in contact with respective resulting inner concave surfaces and without contacting resulting respective outer convex surfaces of the shells or (2) the step of vacuum or differential-pressure forming is performed using a mold surface comprising an array of through holes with the shell structures formed by vacuum or differential pressure forming of the sheet against the mold surface without contacting the resulting respective outer convex surfaces or the resulting respective inner concave surfaces.

主权项

1. A method of producing glass focusing mirror blanks, the method comprising:
providing a glass sheet; heating the glass sheet or otherwise providing for the temperature of the glass sheet to be near the softening point of the glass so as to allow permanent deformation thereof; and reforming the glass sheet so as to form an array of glass shell structures therein by (1) pressing the sheet or (2) vacuum or differential-pressure forming the sheet, the respective resulting glass shell structures each having a respective outer convex surface and a respective inner concave surface, wherein the step of pressing is performed using a positive mold surface comprising an array of protrusions pressed against and in contact with the respective inner concave surfaces and without contacting the resulting respective outer convex surfaces with any solid object, and wherein the step of vacuum or differential-pressure forming is performed using a mold surface comprising an array of through holes with the shell structures formed by vacuum or differential pressure forming of the sheet against the mold surface with the glass shell structures formed into the array of through holes without contacting the resulting respective outer convex surfaces with any solid object and without contacting the inner resulting respective inner concave surfaces with any solid object.