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IRDK17 (Infrared Optimized)

SKU# 170120Q

Price: $26,000.00


*Price is based on PlaneWave’s Pricing Policy

The IRDK17 is a 17-inch infrared-optimized optical tube designed for research applications where on-axis performance is crucial.

  • Dall-Kirkham optical design
  • Focal length of 2,939 mm (f/6.8)
  • Mirror coatings that are optimized to transmit in infrared wavelengths (ultraviolet optimization available)
  • Fused silica mirrors with low thermal expansion
  • Ready for Delta-T dew prevention


This is a Dall-Kirkham optical design with coatings that are optimized to transmit in infrared wavelengths. There are no refractive lenses, only reflective components to the design. For IR application, reflective coatings are a protected gold that gives better than 98% reflectivity from .65 micron (650nm) to 5 micron (5000nm). This design is ideal for infrared astronomy or LIDAR applications. UV-optimized coatings can be provided as well, so please reach out to our technical sales team to discuss UV optimization.

  • IRDK17 is a 17-inch infrared-optimized optical tube with fused silica mirrors
  • Focal length of 2,939 mm (f/6.8)
  • Dall-Kirkham optical design with coatings that are optimized to transmit in infrared wavelengths (ultraviolet optimization available)
  • Ready for Delta-T dew prevention


IRDK 17 Features

Carbon Fiber Truss Design


Minimizes thermal expansion which causes focus shift as temperature changes during an imaging session. Carbon fiber also reaches ambient temperatures quickly and is extremely lightweight and rigid to help ensure excellent imaging data is produced.

3D Printed Baffles


PlaneWave uses digital 3D printing technology to produce lightweight baffle tubes. 3D printers add successive layers of material to construct a baffle system with precision positioned internal stray light baffles to minimize vignetting and maximize image contrast. Quality baffling makes an incredible difference in overall image quality, so we ensured an optimal design was created for our telescopes.

Dovetail Expansion Joint


Allows for the difference in thermal expansion between carbon fiber and aluminum. The expansion joint allows the aluminum dovetail to expand and contract without stressing the carbon fiber lower truss. This results in images that are not distorted due to expansion, or contraction of the optical tube materials.

Delta-T Ready


For added dew prevention, the IRDK17 is internally wired with polyimide film heater pads and temperature sensor, which is ready to be controlled with the Delta-T via PlaneWave Interface 3 software.

Cooling Fans


Three fans on the backplate of the optical tube pull air through the telescope and by the primary mirror. Three fans on the side of the optical tube also blow air across the primary to ensure a boundary layer of air does not distort images. These fans help the telescope reach thermal equilibrium quickly, further reducing any distortion in images due to temperature variations. The fans are controlled by a switch on the optical tube, or can be controlled by via PWI3 software if a PlaneWave Electronic Focus Accessory (EFA Kit) is purchased.



Optical System

Optical Design Infrared Dall-Kirkham
Aperture 17 inch (432 mm)
Focal Length 2939 mm (115.71 inch)
Focal ratio F/6.8
Central Obstruction 23.7% by surface area; 48.6% of the primary mirror diameter
Back Focus from Mounting Surface 10.32 inch (262.33 mm)
Back Focus from Racked in Focuser 7.24 inch (184 mm)
Weight 106 lbs (48 kg)
OTA Length 42 inch (1067 mm)
Optical Performance 6.5 micron rms at 21mm and 9.6 micron at 26mm off-axis
Upper Cage Carbon fiber truss
Lower Cage Carbon fiber truss with carbon fiber light shroud
Optimal Field of View 70mm image circle

Secondary Mirror

Diameter 190 mm (7.48 inch)
Material Fused silica (quartz)
Shape Spherical
Coating Gold Protected

Primary Mirror

Optical Diameter 17 inch (432 mm)
Outer Diameter 17.5 inch (445 mm)
Shape Prolate ellipsoid
Material Fused silica (quartz)
Coating Gold Protected


Crated Shipping Weight 225 lbs   (102.1 kg)
Crate Width 30 inch   (762 mm)
Crate Height 37 inch   (940 mm)
Crate Length 58 inch   (1,473 mm)


Included Items

Included Items

Primary Mirror Cover To protect the primary mirror
PlaneWave Thumb Drive Contains software and instructions for collimation and spacing the primary to secondary mirror
12VDC Power Supply Provides power for the fans (Not included for European orders)
Wrench Set
Standard hex wrenches (European orders only)





For warranty information please check our Standard Warranty Page.