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An essential goal for physics and optical science instructors is to encourage students to find excitement and beauty in physical and optical phenomena while helping them learn the theoretical concepts and conducting experiments that can test the validity of the concepts. Such motivation largely relies on realistic hands-on lab opportunities where students can interact with physics-based phenomena as well as their corresponding laws and principles. Virtual simulation and modeling tools provide a great alternative to deliver interactive experiences when participating in physical lab environments is limited or unavailable (i.e., during distance learning due to the COVID-19 pandemic). The use of computer-based simulations can improve students' ability to make predictions and explain the phenomena practiced in the experiments. The educational value of virtual labs has been extensively investigated and reported, showing that students who use simulated equipment outperformed their peers.

One of the most profound and philosophically captivating foci of modern astronomy is the study of Earth-like exoplanets in the search for life in the Universe. The paradigm-shifting investigation described here calls for a new type of scalable space telescope that redefines the available light-collecting area in space. The Nautilus Space Observatory, enabled by multiple-order diffractive optics (the MODE lens), is ushering in the advent of large space telescope lenses designed to search for biosignatures on a thousand exo-earths. The Kinematically Engaged Yoke System (KEYS) was developed to align a segmented version of the MODE lens. A technology demonstration prototype of KEYS was built and tested using scanning white light interferometry and deflectometry. A deflectometry system was also developed to monitor the closed-loop alignment of the segmented MODE lens during its UV (i.e., Ultraviolet) curing. [ABSTRACT FROM AUTHOR]

Grazing-incidence reflective optics are commonly used in synchrotron radiation and free-electron laser facilities to transport and focus the emitted X-ray beams. To preserve the imaging capability at the diffraction limit, the fabrication of these optics requires precise control of both the residual height and slope errors. However, all the surface figuring methods are height based, lacking the explicit control of surface slopes. Although our preliminary work demonstrated a onedimensional (1D) slope-based figuring model, its 2D extension is not straightforward. In this study, a novel 2D slope-based figuring method is proposed, which employs an alternating objective optimization on the slopes in the x- and y-directions directly. An analytical simulation revealed that the slopebased method achieved smaller residual slope errors than the height-based method, while the height-based method achieved smaller residual height errors than the slope-based method. Therefore, a hybrid height and slope figuring method was proposed to further enable explicit control of both the height and slopes according to the final mirror specifications. An experiment to finish an elliptical-cylindrical mirror using the hybrid method with ion beam figuring was then performed. Both the residual height and slope errors converged below the specified threshold values, which verified the feasibility and effectiveness of the proposed ideas. [ABSTRACT FROM AUTHOR]

Standard mid-spatial frequency tooling mark errors were parameterized into a series of characteristic features and systematically investigated. Diffraction encircled and ensquared energy radii at the 90% levels from an unpowered optical surface were determined as a function of the root-mean-square surface irregularity, characteristic tooling mark parameters, fold mirror rotation angle, and incident beam f-number. Tooling mark frequencies on the order of 20 cycles per aperture or less were considered. This subset encompasses small footprints on single-point diamond turned optics or large footprints on sub-aperture tool polished optics. Of the characteristic features, off-axis fabrication distance held the highest impact to encircled and ensquared energy radii. The transverse oscillation of a tooling path was found to be the second highest contributor. Both impacts increased with radial tooling mark frequency. [ABSTRACT FROM AUTHOR]

Phase measuring deflectometry has been applied for free-form specular surface metrology, but its measured slope results are sensitive to the depth of sample positioning, which is also called the height-slope ambiguity. The objective of this work is to tackle this height-slope ambiguity problem. The main idea is to introduce collimated camera rays using a telecentric imaging lens and collimated structured-light illumination with a Fourier lens. This setup makes the fringe phases become only sensitive to the surface slopes and insensitive to the depth of the sample positioning. In this way, the slope calculation is theoretically independent of the sample depth. We call this new deflectometry technique Collimated Phase Measuring Deflectometry (CPMD). With our developed CPMD experimental setup, the measurement is insensitive to the depth of sample positioning, e.g. , the measured height dispersion is less than 30 nm RMS within a 10 mm depth range when measuring a 50-mm-diameter spherical mirror with a 200 mm radius of curvature. The merits and limitations of the proposed CPMD technique are discussed, revealing its prospects in practical metrology applications and potential future investigations. • We proposed Collimated Phase Measuring Deflectometry (CPMD) for optical metrology. • The CPMD theoretically eliminates the height-slope ambiguity in deflectometry. • Collimated camera rays and illuminations relax the tolerance for sample positioning. • This feature opens new potential metrology applications by using CPMD. • It allows for more practical measurements, such as the inspection of freeform optics. [ABSTRACT FROM AUTHOR]