Advanced treatment of optical reflective surface blackening
Journal
Proceedings of SPIE the International Society for Optical Engineering
Part Of
Proceedings of SPIE - The International Society for Optical Engineering
Journal Volume
13699
Start Page
136995U
ISSN
0277-786X
1996-756X
ISBN
[9781510693470]
Date Issued
2025-07-28
Author(s)
Editor(s)
Bernard, Frédéric
Karafolas, Nikos
Kubik, Philippe
Minoglou, Kyriaki
Abstract
In this paper, we propose two blackening treatment methods to suppress stray light for future applications in observational remote sensing telescopes. Traditionally, remote sensing telescope component surfaces are treated by either attaching or coating them with space-grade blackening materials. This approach can achieve a total integrated reflectance (TIR) of less than 2% at incident angles up to 45°. However, as the incident angle increases beyond 45°, the TIR correspondingly rises, reaching as high as 6.3% at an 80° incident angle. Therefore, we propose two surface blackening treatments: one for non-3D-printable metals (e.g., Invar 36 and Al6061) and another for 3D-printable materials (e.g., Ti6Al4V, resin, and polymers). For non-3D-printable metals, the blackening process involves first creating micron-scale structures using a high-energy laser, followed by coating the surface with a blackening material (BM). This method achieves a TIR of 0.61% to 4.3% for incident angles ranging from 8° to 80°. For 3D-printable materials, microstructures are created during the 3D printing process, and the surface is then coated with Z307 or Black Matrix, yielding similar TIR results. Both methods offer over twice the stray light suppression compared to traditional techniques. In the future, these surface treatments will undergo various environmental tests to validate their applicability in upcoming space projects.
Event(s)
International Conference on Space Optics — ICSO 2024
Subjects
3D print microstructure
6U cube-sat
bidirectional reflectance distribution function
blackening treatment
FORMOSAT-8
laser microstructure
Publisher
SPIE
Type
conference paper