DFM Engineering

DFM Engineering. The company is a prominent American manufacturer of professional-grade optical telescope systems and observatory infrastructure, founded in 1978 by optical engineer Douglas B. McKenna. Specializing in the design and construction of medium to large-aperture instruments, it has supplied telescopes and related systems to major university departments, national observatories, and planetarium facilities worldwide. The firm is recognized for its innovative and robust engineering, particularly in the development of high-performance altazimuth mounts and automated observatory systems.

History

The company was established in 1978 by Douglas B. McKenna, an engineer with extensive experience in aerospace optics and precision engineering. Initial projects focused on designing and fabricating specialized components for the astronomical community, including work for institutions like the University of Denver and the United States Air Force Academy. Throughout the 1980s and 1990s, the firm gained a reputation for building reliable, research-class instruments, leading to contracts for complete turnkey observatories. Key to its growth was the development and refinement of its proprietary servo drive systems and computerized telescope control software, which allowed for precise tracking and pointing essential for modern astrophotography and photometry. This period saw the company move to larger facilities in Longmont, Colorado, to accommodate the construction of ever-larger optical assemblies.

Products and Services

The primary offerings include complete Cassegrain and Ritchey–Chrétien telescope optical systems, ranging from 0.5-meter to 2.0-meter apertures. The company manufactures all critical subsystems in-house, including massive fork mounts and English equatorial mounts, Serrurier truss structures, and observatory domes with automated slit operation. A core service is the design and integration of sophisticated observatory control systems, which orchestrate the telescope mount, dome, instrument rotators, and adaptive optics systems. The firm also provides extensive site testing and observatory construction management, working with clients from initial planning through to final commissioning and observatory automation.

Telescope Designs

The company is renowned for its optimized Ritchey–Chrétien optical designs, which provide wide, coma-free fields ideal for CCD camera imaging and spectroscopy. Its mechanical designs emphasize stiffness and thermal stability, utilizing materials like Invar and carbon fiber to minimize thermal expansion effects on optical alignment. A signature innovation is the implementation of extremely rigid altazimuth mounts with direct-drive torque motors on both axes, eliminating traditional worm gear systems and their associated periodic error. These mounts are often housed within compact, thermally controlled enclosures that utilize active optics principles to maintain optimal performance. The optical fabrication is typically outsourced to specialist firms like LOMO or Richardson Grating Laboratory, with the company performing final alignment and optical testing using Foucault knife-edge test and interferometry.

Notable Installations

The company's telescopes are installed at major research facilities across the globe. Significant installations include the 1.8-meter Plaskett Telescope upgrade at the Dominion Astrophysical Observatory in Canada, and the 1.3-meter Robotically Controlled Telescope at the Skinakas Observatory in Greece. In the United States, notable systems include the 1.0-meter telescope at the Kitt Peak National Observatory, the 0.8-meter instrument at the Sommers-Bausch Observatory of the University of Colorado Boulder, and the 0.6-meter telescope at the Frosty Drew Observatory. Internationally, the company has delivered instruments to the Mount John University Observatory in New Zealand, the Wise Observatory in Israel, and the Saint Mary's University (Halifax) in Nova Scotia.

Company Operations

The firm operates from its design and manufacturing facility in Longmont, Colorado, employing a team of optical, mechanical, and software engineers. Project management follows a collaborative model, working closely with client astronomers from institutions like the University of North Carolina at Chapel Hill or the United States Naval Observatory to define specific scientific requirements. The manufacturing process integrates modern computer-aided design and finite element analysis with traditional precision machining and welding. While the company has occasionally collaborated on projects with larger entities like the Association of Universities for Research in Astronomy, it remains a privately held, specialist firm focused on the high-end professional and institutional market, distinct from the mass-market commercial telescope industry dominated by companies like Celestron and Meade Instruments.

Category:American companies established in 1978 Category:Telescope manufacturers Category:Companies based in Boulder County, Colorado