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Point Diffraction Interferometer
The Smartt interferometer or its evolution, the Phase-shifting point diffraction interferometer is probably the most accurate one can make, and it is not even expensive. It has its limitation, doesn’t everything, such as that we need a focus to create a reference wave with a pinhole. If the focus is at a high numerical aperture,…
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Coherence
Coherence is perhaps the most interesting property of light and arguably, the effects of interference are at the core of what we consider to be the field of optics. Yet, you don’t have to look too far to find an optics specialist that simply will not have anything to do with it. In practice, we…
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Wavefront Metrology
Optical wavefront measurement, or wavefront metrology, is a big subject. In this tech talk, we will focus on two topics which could even be considered dichotomies, phase-shifting interferometry and Shack-Hartmann wavefront sensing. With phase-shifting interferometry, accuracy is key and every nanometer is significant. Speed and versatility come second. Quite the opposite can be said for…
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Optical System Design
The meaning of optical system design varies depending on whom you ask. In my view, it’s more of an ongoing process than a single task. A process is something you execute continuously, using feedback to refine and improve each stage of development. On the other hand, a task focuses on developing a specific system or…