TransCal – An Innovative, Highly Accurate, Transmissive Radiometric Calibration Approach

TransCal is an innovative calibration approach using Polymer Dispersed Liquid Crystal (PDLC) material to continue the precise solar diffuser based radiometric calibration used extensively in the Landsat program, while significantly reducing the size and complexity of the calibration subsystem. An essential aspect underlying the utility of the long-term Landsat data record is extensive pre-launch sensor characterization and on-orbit calibration. To improve on current earth remote sensing capabilities, the Sustainable Land Imaging-Technology (SLI-T) 2019 program aims to reduce resources needed (e.g., cost, size, volume, and mass) for the next generation SLI instruments, while meeting or exceeding the current Land Imaging capabilities, with emphasis on improved temporal, spatial, and spectral resolution. TransCal meets this objective of reducing sensor Size, Weight, and Power (SWaP) while maintaining critical radiometric performance. PDLC material is composed of liquid crystal (LC) micro-droplets encased in a transparent polymer matrix. The orientation of the LC molecules defines the optical, electrical, magnetic, and mechanical properties. In its nominal state, each LC micro-droplet is randomly aligned, resulting in a high degree of optical scattering and creating an opaque, diffuse PDLC material. The LC molecules orientation may be controlled through weak electric or magnetic fields. To accomplish this, the PDLC material is typically flanked by thin conductive layers of Indium Tin Oxide (ITO). This enables the application of a local electric field which preferentially orientates the LC molecules across all droplets and renders the PDLC optic transparent. The objectives of the TransCal program are to develop a TransCal PDLC optic and to fully characterize this optic as a reversible, highly accurate solar diffuser permanently located in the optical path of a future sensor. Full characterization will include spectral transmittance, Bidirectional Transmittance Distribution Function, and the transmitted wavefront. The temporal stability and radiation testing will verify its applicability for space flight instrumentation. Finally, the on-orbit imaging and calibration performance will be modeled and verified with an operational sensor such as the Compact Hyperspectral Prism Spectrometer (CHPS). To achieve this, we propose a two-year-long program beginning at TRL 2 and exiting at TRL 4.

Accelerate mission development, reduce risks and costs for future Sustainable Land Imaging missions

This is early/mid-stage (TRL 4) — 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.