SYSTEMS AND METHODS FOR PROVIDING MIRRORS WITH HIGH STIFFNESS AND LOW INERTIA INVOLVING CHEMICAL ETCHING
A method is disclosed of fabricating a mirror for use in limited rotation motor systems, said method comprising the steps of providing a mirror structure including at least one wall section, and exposing the at least one wall section to a fluid etching agent to thereby provide chemical milling of the mirror structure.
1 . A method of fabricating a mirror for use in limited rotation motor systems, said method comprising the steps of providing a mirror structure including at least one wall section, and exposing the at least one wall section to a fluid etching agent to thereby provide chemical milling of the mirror structure.
2 . The method as claimed claim 1 , wherein said mirror substrate includes beryllium.
3 . The method as claimed in claim 1 , wherein said fluid etching agent includes hydrofluoric acid (HF).
4 . The method as claimed in claim 1 , wherein said fluid etching agent includes nitric acid (HNO 3 ).
5 . The method as claimed in claim 1 , wherein said method includes the step of applying a mask to a protected area to prevent etching of the protected area.
6 . The method as claimed in claim 5 , wherein said protected area is a front reflective surface of the mirror.
7 . The method as claimed in claim 1 , wherein said method further includes the step of agitating a bath that includes the beryllium structure and the fluid etching agent.
8 . The method as claimed in claim 7 , wherein said method further includes the step of controlling a rate of agitation of the bath that includes the beryllium and the fluid etching agent to control a shape of the at least one wall section.
9 . The method as claimed in claim 1 , wherein said mirror structure is removed from the fluid etching agent when the mirror reaches a target reduced weight.
10 . The method as claimed in claim 1 , wherein said method further includes the step of drawing the beryllium structure from the fluid etching agent at a controlled rate such that the at least one wall section forms a tapered wall.
11 . The method as claimed in claim 1 , wherein said method provides uniform milling of exposed surfaces of the beryllium structure.
12 . A mirror for use in a limited rotation motor systems formed from the method of claim 1 .
13 . A mirror for use in a limited rotation motor system, said mirror comprising a backing structure opposite a front of the mirror, said backing structure including at least one wall section having a tapered shape that tapers as the wall extends away from the front of the mirror.
14 . The mirror as claimed in claim 13 , wherein said backing structure includes beryllium.
15 . The mirror as claimed in claim 13 , wherein said wall sections are formed by chemical etching.
16 . The mirror as claimed in claim 13 , wherein said tapered shape of the wall section has a thickness of no greater than about 0.25 mm.
17 . The mirror as claimed in claim 13 , wherein said backing structure includes a plurality of hexagonally shaped wall sections each of which is tapered as the wall extends away from the front of the mirror.
18 . A mirror for use in a limited rotation motor system, said mirror comprising a backing structure opposite a front of the mirror, said backing structure including features that provide rigidity to the mirror and that have thicknesses that become reduced in a direction away from the front of the mirror.
19 . The mirror as claimed in claim 18 , wherein said backing structure includes beryllium.
20 . The mirror as claimed in claim 18 , wherein said features have thicknesses of no greater than about 0.25 mm.