Mirrors, lenses, windows and baffles forming the image.
What decides the purchase: Aperture · focal length · surface figure (RMS wavefront) · coating reflectance · stray light rejection
Typical materials: Zerodur, ULE, silicon carbide, fused silica, aluminium
Typical processes: Grinding, polishing, ion-beam figuring, diamond turning, thin-film coating
What changes when it has to fly: Named independently by two Indian companies as the hardest capability to source domestically — lens and mirror manufacture, including fine-steering mirrors.
Engineering reference written by us, not a supplier claim.
No Indian supplier in this index makes telescope optics, plus 1 international.
| Supplier | Location | Certifications | Evidence |
|---|---|---|---|
| Excelitas (Qioptiq) intl | international | — | stated capability |
Certifications are as published by each company and unverified. "Product indexed" means we hold an actual product record; "stated capability" means the company says it does this.