PlaneWave IRDK 20" Fused Silica
New product
20" f/6.8 Dall-Kirkham telescope optimized for infrared, with Fused Silica optics, fully reflective design, and 20 mm diffraction-limited field.
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Description:
The PlaneWave IRDK20 is a 508 mm infrared-optimized Dall-Kirkham telescope designed for scientific infrared astronomy and LIDAR applications. It features a purely reflective optical path with no lenses. Mirrors are coated with protected gold, achieving over 98% reflectivity from 650 nm to 5000 nm. Optional UV-optimized coatings are also available.
The optics are made of Fused Silica, a high-purity synthetic glass with excellent thermal and optical stability. It offers a thermal expansion coefficient six times lower than Pyrex, maintaining optical precision and focus over temperature changes.
The IRDK20 delivers diffraction-limited performance over a 20 mm image circle. The OTA includes an 8" dovetail and is compatible with the 3.5" Hedrick focuser and optional EFA Kit. It is Delta-T Ready, with internal wiring for primary and secondary mirror heaters (controller #1329110 required, not included).
The carbon fiber structure ensures rigidity and minimal thermal distortion, making this system ideal for long-exposure imaging and scientific research.
Technical specifications:
Optical design: Dall-Kirkham (infrared optimized, reflective)
Aperture: 20" (508 mm)
Focal length: 3454 mm (135.98 inch)
F-ratio: f/6.8
Corrected field: 20 mm (diffraction limited)
Back focus: 8.9" (226 mm) from mounting surface, 5.81" (147 mm) from racked-in focuser
Central obstruction: 39% of primary mirror diameter
Glass type: Fused Silica
Optical length: 47" (1194 mm)
OTA weight: 140 lbs (64 kg)
Mounting: 8" dovetail
Delta-T Ready: yes (requires controller #1329110, sold separately)
Shipping crate required: #1323520 (charged separately)