Custom Size Telescopes and Optical Systems

DFM Engineering can accommodate your specific requirements whether it is a custom
size, specialized instrumentation or custom optical systems.

A unique project designed and manufactured by DFM Engineering was a 40 cm telescope for a balloon borne experiment.  This telescope used Invar spacers to minimize focus shift with temperature and had special mirror supports to allow the telescope to look below the horizon.

DFM also designed and manufactured several specialized telescopes and instruments for measuring astronomical seeing that utilized hermetically sealed optics that breath through a canister of desiccant.  These telescopes were customized versions of the standard DFM CCT-16 but with special optics, invar spacers and a full aperture optical window with dew shield.

1.6M solar telescope

Sun spot

Another example is the Big Bear Solar Telescope which presents unique problems of scattered light and thermal control.

A 1.6M solar telescope was designed and manufactured by DFM Engineering to study solar surface granulation.

The clear aperture, off-axis telescope design included particular attention to the full light path, from its entrance through the adaptive optics to the final field of view. Calibration and heat uniformity throughout the light path were of primary concern.

The primary mirror is 1.7 m off-axis, which leaves the secondary mirror well-away from the path of the incoming light.

After the secondary, the light comes to the first set of polarization optics, which contains calibration optics.

The tertiary mirror then sends the light down the declination axis of the solar telescope.

The off axis, unobstructed optical system has much reduced diffraction and much less scattered light compared to a concentric Cassegrain configuration.  This combined with adaptive optics and careful temperature control results in very high quality solar images.

The engineering of this high quality optical system enabled observation of solar mini-granules that form a multi-fractal structure in real time.

This discovery of remarkable bursting, jagged behavior, mimicked other systems in nature, such as coastlines, glaciers, earthquakes, etc. providing scientists with extraordinary data.

For more information about the telescope: The New Solar Telescope in Big Bear: Polarimetry II