Lightweight optical elements with honeycomb support plate

Claim 2

A lightweight optical assembly comprising an optically transparent plate, which plate is supported by and fused to a fused silica perforated support structure, which support structure comprises walls extending perpendicular to the major surfaces of said plate wherein said plate is fused to said walls at the interface of the ends of said walls and the rear surface of said plate and wherein the rear side of said plate extends convexly in lens form into the perforations of said supporting structure between the walls thereof, said supporting structure having perforations of a diameter between 40 and 80 mm, substantially uniformly distributed throughout its area, all of said perforations generally extending axially parallel to one another, and there being perforations having a diameter at both ends of said range and at a number of intermediate values with at least some of the perforations having smaller diameter being at the outer peripheral edge of said supporting structure, the walls between said perforations being between 2 and 6.0 mm in thickness.

Claim 3

An optical assembly according to claim 1, wherein the small perforations are substantially uniformly distributed throughout the area of the supporting structure and the diameter of the large and small perforations and the wall thicknesses therebetween have a relationship as set forth in the following table: Diameter of Diameter of Smallest Greatest the large the small remaining wall thick- perforation perforation wall thick-ness in mm in mm ness in mm in mm I 40 15 2.5 4.0 II 50 15-20 3.0 4.0 III 60 15-22 3.0-3.5 4.5-5.0 IV 70 20-25 3.5-4.0 5.0 V 80 22.28 4.0-4.5 6.0

Claim 4

An optical assembly as claimed in claim 1, whereIn said optical plate is quartz glass.

Claim 5

An optical assembly as claimed in claim 1, having a back plate fused to said support structure at the interface between said back plate and the ends of the walls of said support structure opposite the ends thereof fused to said transparent plate, said back plate having apertures therein communicating with said perforations.

Claim 6

An optical assembly as claimed in claim 4, wherein said back plate extends convexly into the perforations of said supporting structure between the walls thereof.

Claim 7

A lightweight optical mirror or window assembly comprising an optically transparent plate, which plate is supported by and fused to a fused silica perforated support structure, which support structure comprises walls extending perpendicular to the major surfaces of said plate wherein said plate is fused to said walls at the interface of the ends of said walls and the rear surface of said plate and wherein the rear side of said plate extends convexly in lens form into the perforations of said supporting structure between the walls thereof, said support structure having perforations of a diameter between 40 and 80 mm, substantially uniformly distributed throughout its area, all extending generally axially parallel to each other, and wherein said perforations comprise large and small perforations with the diameter of the large and small perforations and the wall thicknesses therebetween, having a relationship as set forth in the following table: Diameter of Diameter of Smallest Greatest the large the small remaining wall thick- perforation perforation wall thick-ness in mm in mm ness in mm in mm I 40 15 2.5 4.0 II 50 15-20 3.0 4.0 III 60 15-22 3.0-3.5 4.5- 5.0 IV 70 20-25 3.5-4.0 5.0 V 80 22-28 4.0-4.5 6.0

Claim 8

A lightweight optical mirror or window assembly comprising an optically transparent plate, which plate is supported by and fused to a fused silica perforated support structure, which support structure comprises walls extending perpendicular to the major surfaces of said plate wherein said plate is fused to said walls at the interface of the ends of said walls and the rear surface of said plate and wherein the rear side of said plate extends convexly in lens form into the perforations of said supporting structure between the walls thereof, said support structure having perforations of a diameter between 40 and 80 mm, substantially uniformly distributed throughout its area, all extending generally axially parallel to each other, and wherein said perforations comprise large and small perforations with the diameter of the large and small perforations and the wall thicknesses therebetween, having a relationship as set forth in the following table: Diameter of Diameter of Smallest Greatest the large the small remaining wall thick- perforation perforation wall thick-ness in mm in mm ness in mm in mm I 40 15 2.5 4.0 II 50 15-20 3.0 4.0 III 60 15-22 3.0-3.5 4.5- 5.0 IV 70 20-25 3.5-4.0 5.0 V 80 22-28 4.0-4.5 6.0