Low Coherence, Spectrally Modulated, Spherical Wavefront Probe for Nanometer Level Free-Form Metrology, Phase I

To-date free-form optic manufacture is limited due to inadequate metrology to measure surfaces with free-form and conformal shapes, with large surface slopes and to the required measurement uncertainty. In this proposal we describe a new interferometric non-contact probe capable of measuring free-form optics with nanometer sensitivity. The probe has favorable metrology characteristics and uses a new interferometric modality allowing the advantages of low-coherence interferometry in common path interferometer designs. The combination of high acceptance angles and high sensitivity make possible the use of a simple three-orthogonal-axis metrology frame and fulfills the precision requirements demanded by NASA and industry. The projected data acquisition rates in excess of 10 kHz will provide an attractive manufacturing metrology tool. More »