Melles Griot Increases Optics Group Polishing Capability

ROCHESTER, NY, Feb. 12 -- Melles Griot Optics Group announced it recently commissioned installation of its QED Q22-Y magnetorheological (MRF) finishing system and large-aperture, digital phase-measuring interferometer at its Rochester, N.Y., manufacturing complex, in a new class-10,000 clean facility.

The company said the system will enable it to produce spherical surfaces accurate to 1/250 of a wavelength, root-mean-square (rms), at 632 nm, using the "3-sphere" calibration method. The system uses a computer-directed, electromagnetically controlled "ferro-fluid" polishing method to selectively reduce the height of nanometer-scale surface features on optical elements, reducing rms surface roughness to the 5-angstrom region.