Satin Finished Straight Edge — Titanium Satin Finished Straight Edge — Optical Straight Edge

Satin-Finished Straight-Edge


One of the desirable tests, for optical scanners, of all types, is to measure the geometry of a really flat surface. The major difficulty with this, is that spectral reflectivity or local hot spots received from the flat surfaces of any standard material, disturbs the systems ability to evaluate the geometry of the subject. The normal procedure used to reduce the spectral reflectivity is to spray the test surface with a satin texture coating. The problem that is created by this technique, is that, the uneven deposit of the spray coating appears to be an error in flatness. The sprayed on coating always accumulates a heavier deposit at the edges. The perfect solution to this problem, is to use a very flat block of titanium metal that is ground and electro etched simultaneously, to produce an almost perfectly flat satin finished surface, that has no spectral reflectivity, at all.

The perfect satin finish of titanium, is probably based on the fact that the crystallographic structure of titanium is a hexigonical close pack, instead of the normal cubic structure  of other metals. In contrast to, the almost black surfaces, other attempts to produce artifacts for optical scanner calibration, that aren’t shiny, satin finished titanium procedures good optical images. The standard model SFF-2-4 is 4 inches (101.6mm) long, 2 inch (50.8mm) wide and 1.5 inches (38.1mm) thick. The 4 inch (101.6mm) by 2inch (50.8mm) surface is satin finished.

The larger version SFF-2-8 is 8 inches (203.2mm) long 2 inches (50.8mm) wide and 1.5 inches (38.1mm) thick. The 8 inch (203.2mm) by 2 inch (50.8mm) surface is satin finished. We have occasionally satin finished multiple surfaces of the titanium block, for special customer applications. The grind etch process, that produces the satin finish, is a slow, expensive procedure, that is only applied as needed. We have developed, a unique mounting device, to hold these satin finished straight edges, for optical evaluation. By using this unique, double sphere, mounting device, the satin finished titanium straight edges can be held without distortion in our standard Ball Bar clamp.

The ball bar clamp, along with the satin finished straight edge, can be mounted on the collar, of any of our Heavy Duty Stands or any of the Anchor Systems, (see our website). Using this clamping approach, the satin finished titanium straight edge, can be located at any height and at any angle in either plane.

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