Wide Range Interferometric Probe

From flagship observatories to small earth-observation satellites, many NASA missions require high performance optical components that are also cost-effective to manufacture and launch. Freeform optical components can reduce a telescopes size and weight (reducing launch costs) but are challenging to test and validate with traditional metrology tools due to their lack of symmetry and large changes in curvature (increasing manufacturing costs). Improved metrology systems for freeform optics have potential to improve performance and reduce manufacturing costs by avoiding prescription-specific null correctors or holograms. Metrology systems for freeform optics require a challenging combination of capabilities: high-resolution (ideally sub-nanometer) measurement of large deviations from a planar surface and steep surface slope. At OptiPro Systems, we have recently developed (in part through NASA SBIR projects) an interferometric probe capable of sub-nanometer metrology of optical surfaces, which is essential for precision optical components such as telescope mirrors. In Phase I, we designed probes capable of measuring large surface sag and steep surface slope, which would allow direct application of these probes to freeform optics. We propose constructing, testing, and calibrating new prototype interferometric probes that will enable cost-effective metrology of freeform optics. These probes have long measurement range and wide acceptance angle while maintaining sub-nanometer performance. Using the results of our Phase I, we have completed a major redesign of the probe optical system. The Phase II project aims to finalize the optical design; construct, align, and calibrate these probes; and deliver a report detailing the prototype probes performance and their potential use in metrology of high-performance freeform optics. The quality of optical components determine the performance of advanced space telescopes and Earth-observation satellites. At the same time, cost is a factor in telescope design, and compact telescopes may be less expensive. Future telescopes may be able to improve both performance and cost metrics using freeform optics, which lack rotational symmetry, and fast F/# designs using optics with steep curvature.   One sticking point is the difficulty of precisely measuring the shape of freeform and fast F/# surfaces, requiring a challenging combination of 1) measurement resolution, 2) measurement range (surface sag), and 3) acceptance angle (steep slopes).   In this proposal, we offer improved metrology of freeform and fast F/# optical components by fundamental enhancements to OptiPro's non-contact metrology probe that extend the measurement range and acceptance angle. Specific innovations include: 1) increased measurement range using multiple reference paths, 2) increased acceptance angle by optimizing interference fringe contrast, and 3) custom calibration system for sub-nanometer accuracy. The technical objectives of the Phase II project focus on improving the capabilities of OptiPro's Nanometric Probe for measurement of freeform, fast F/#, and large diameter optical components while maintaining sub-nanometer performance.   Specifically, we aim to: Design and construct a calibration system capable of measuring nanometer-scale slope-dependent inaccuracy. Design, construct, and test a prototype Wide-Angle optical probe capable of measurements on steeply sloped surfaces. Design, construct, and test a prototype Long-Range optical probe capable of measurements over a long range of distances.   The deliverable at the end of Phase II is a detailed report containing the design and test performance of the slope-dependent calibration system, Wide-Angle Probe, and Long-Range Probe. The suitability for integrating these probes into existing and future metrology systems, such as CMM’s and OptiPro’s UltraSurf, will be evaluated.

Potential NASA applications include metrology of freeform and other optical components for NASA missions, including flagship/decadal missions, small satellites, and everything between. Some specific applications: Origins Space Telescope (OST) and Large UV/Optical/IR Surveyor (LUVOIR), which may use freeform optics. Lynx, Advanced X-ray Imaging Satellite (AXIS), and other X-ray telescopes. Large telescope mirrors, such as those for the Habitable Exoplanet Observatory (HabEx), OST, and LUVOIR, requiring sub-nanometer metrology. The proposed metrology probe would benefit many applications, including: Metrology of high-precision optical components for commercial products Metrology of x-ray and neutron mirrors (Department of Energy) Vibration analysis of mechanical components and machines

This is early/mid-stage (TRL 3) — the most realistic path in is NASA SBIR/STTR, which funds small businesses and research institutions to develop technology aligned with NASA's needs (equity-free, phased funding). Check whether a current SBIR/STTR solicitation topic overlaps with this project's technology area, or contact the project directly (above) to ask.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.