Telephoto- lens-based Optical Differentiation Wavefront Sensor for freeform metrology

We report an Optical Differentiation Wavefront Sensor based on a telephoto lens system and binary pixelated filters. It provides a five-fold reduction in the system length compared to a 4f system with identical effective focal length. Measurements of phase plates with this system are compared to measurements performed with a commercial low-coherence interferometer. The telephoto-lens-based system can measure wavefronts with accuracy better than lambda/10 Root Mean Squared (RMS) at lambda=633 nm. Experimental investigation shows that the system has a high tolerance to components alignment errors. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.

Automated summary

An Optical Differentiation Wavefront Sensor based on a telephoto lens system and binary pixelated filters is reported in this study, which can measure wavefronts with accuracy better than lambda/10 Root Mean Squared (RMS) at lambda=633 nm. The system shows a high tolerance to components alignment errors in experimental investigation.