Patent ID: 6459487
Filing Date: 2002-10-01
Classification: G02B

Abstract:
A system for enabling manufacture of elements of precise optical path length to levels of precision needed for DWDM filtering applications, comprising:an adjustable monochromatic optical wavelength source providing a test beam output; a scanning control coupled to the source to vary the test beam output sequentially through incrementally varying wavelengths; an optical delay line system coupled to receive the test beam from the source and including at least one input beam displacer for receiving the test beam and propagating two beams in parallel along a first and second delay path, at least one output beam displacer for recombining beams from the first and second delay paths into a single, co-propagating path, the two delay paths each being adapted to receive one or more glass elements, each of different optical path length, and an optical transmission analysis system receiving recombined beams from the delay line system and providing an output representing the frequency periodicity of the recombined optical beams, the frequency periodicity resulting from the interference of beams traveling along the different optical delay paths.