Low-coherence interferometer for contact lens surface metrology

Application of optical coherence tomography to automated contact lens metrology.

Optical coherence tomography (OCT) is a nondestructive imaging modality with the potential to make quantitative spatial measurements. OCT's noncontact nature, sensitivity to small refractive index mismatches, and micron-scale resolution make it attractive for contact lens metrology, specifically, measuring prism. Prism is defined as the maximum difference in thickness of the contact lens, measu...

A "virtual-interferometer" technique for surface metrology.

We demonstrate a novel technique for performing aberration-corrected surface metrology within existing wavefront-feedback systems. Our technique uses several phase measurements to calculate phase differences that directly reveal the surface gradients of an object under test, due to orthogonal displacements of that object between measurements. We then apply a least-squares algorithm for surface ...

New Millennium Interferometer Laser Metrology Testbed New Millennium Interferometer Laser Metrology Testbed by

The New Millennium Interferometer Laser Metrology Testbed is a technology demonstration for a key component of the New Millennium Interferometer (NMI). For the success of NMI, NASA's proposed mission to fly a space-based interferometer, control of its position must be very precise. Laser Metrology is a powerful tool that uses interferometry to make hyper-fine distance measurements. The proposal...

Contact Lens Anterior Surface pH (Reprint)

A clinical decision support system for contact lens evaluation

Background: Contact lenses are transparent, thin plastic disks that cover the surface of the cornea. Appropriate lens prescription should be performed properly by an expert to provide better visual acuity and reduce side effects. The lens administration is a multi-stage, complex and time-consuming process involving many considerations. The purpose of this study was to develop a decision support...