Search

The application of precision interferometers is generally restricted to expensive and smooth high-quality surfaces. Here, we offer a route to ultimate miniaturization of interferometer by integrating beam splitter, reference mirror and light collector into a single optical element, an interference lens (iLens), which produces stable high-contrast fringes from in situ surface of paper, wood, plastic, rubber, unpolished metal, human skin, etc. A self-referencing real-time precision of sub-20 picometer (~ lambda/30000) is demonstrated with simple intensity detection under ambient conditions. The principle of iLens interferometry has been exploited to build a variety of compact devices, such as a paper-based optical pico-balance, having 1000 times higher sensitivity and speed, when compared with a high-end seven-digit electronic balance. Furthermore, we used cloth, paper, polymer-films to readily construct broadband acoustic sensors possessing matched or higher sensitivity when compared with piezo and electromagnetic sensors. Our work opens path for affordable yet ultra-precise frugal photonic devices and universal micro-interferometers for imaging., Comment: This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in (P. Munjal & K. P. Singh, Appl. Phys. Lett., 115(11), 111102, (2019) (https://doi.org/10.1063/1.5108587))