DFM Engineering, Inc.
1035 Delaware Ave. Unit D
Longmont, CO 80501
Phone: 303-678-8143
Fax: 303-772-9411


Telescope Optics Custom Features


DFM Engineering delivers the assurance that only experience can provide. Every optical system is custom created to meet customers' specifications and optical requirements.

telescope optics custom features
Telescope Optical Tube Assembly Sample

The DFM Engineering Team has considerable experience handling large optics typically used in telescopes.

DFM has engineered mirror handling systems to safely allow technicians to remove, reinstall, and collimate the optics.

Also, all primary and secondary mirror finishes are tested at DFM so as to be within proper range.

Large optical flats (0.9-m and 1.6-m), several smaller flats, an interferometer in addition to a 2 ton variable speed electric hoist and a gantry crane allows for safe and efficient handling of large optics.

field corrector diagram
3 Element Field Corrector Diagram

• DFM concentrates on fast, highly aspheric primary mirrors.

• Mirrors are typically 1.3-m F/2.3 mirrors for the wide field F/4 telescopes.

• These mirrors have a surface departure from the best fit sphere of 60 waves.

In the optics shop, DFM has completed:
• five 1.3-m primary mirrors
• a 1-m primary mirror
• a 1.3-m Hindle sphere

prime focus instrument
Prime Focus Corrector Diagram


DFM has also made several field corrector elements which are fourth order (Schmidt) type lenses that are used with the 1.3-m F/4 wide field telescopes. A 3 element field corrector is featured in the ATLAS Optical Tube Assembly (Asteroid Tracker), also manufactured at DFM.

DFM has created and manufactured a Prime Focus Instrument™ (PFI™). A PFI™ retrofitted to older telescopes can allow them to be re-purposed to perform wide field astronomy such as multi object photometry, super nova patrol, variable stars, planetary transits, occultations, orbital debris searches, asteroid searches, etc. With a PFI™ the FOV can be increased to 1° or more.



•  Telescope Optics

•  Standard Features

•  Observatory Dome & Pier