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Glass
Coating
Quality Examination 
Quality Warranty
Alluna Ritchey Chretien Telescopes 
Alluna Newtonian Astrograph Telescopes

Info: Ritchey-Chretien or Dall Kirkham Telescope?
Info: Easy collimation of a Alluna Ritchey Chrétien Telescope
 
 
 
Intoduction
No matter whether you need a parabolic, hyperbolic, or spherical mirror. At Alluna Optics you will receive the suitable optices manufactured for highest demands and exactly fitting to your telescope and your specific application.  We manufacture primary mirrors and complete Ritchey-Chrétien Cassegrain systems of highest accuracy and surface smoothness. Our lenses are known for their high quality. Sharp star images, high resolution at highest contrast characterise our primary mirrors and secondary  mirrors. Our clients are manufacturers of premium telescopes, public observatories, research institutions and ambitious amateur astronomers who want to be sure to have a perfect optics. Our customers include, for example, Germany's national research center for aeronautics and space DLR, the Bern Physics Institute Space research & planetology, the International Amateur Observatory IAS and many more. We produce large-sized single optics for industry, research and technology, for example for striation optics, LIDAR telescopes, collimators, laser technology and other applications.. 

Alluna Ritchey Chrétien and Newtonian astrographs are extremely high-quality, durable and value conserving telescopes. Know-how, experience, best materials as well as most advanced construction/manufacturing processes provide for top class telescopes "Made in Germany".


 
Glass
Producing high-quality telescope mirrors requires high-quality glass. Mostly we use "Pyrex ® No. 7740 fine annealed and precision annealed " for the smaller sizes. Since the production of Pyrex was stopped we also use Suprax or Supremax from Schott as replacement material. 
For larger mirrors and for particularly high-quality applications we use glass ceramic Zerodur. Glass ceramics offer the advantage of a lower thermal expansion coefficient of about 0.1 × 10-6 1 / K. Hence it shows virtually no expansion in case of temperature changes. 
We choose the thickness of the glass in a way that no surface deflexion will occur under normal, appropriate storing conditions. 

 
Cassegrain Optik
20" Pyrex Cassegrain f2,5

24-inch glass-ceramic mirror


 
Coating
We offer aluminuim coating with a reflection of 94% as standard coating, whereas the actual reflection in fact is higher than 94% throughout almost the entire visible wavelength range. For special applications we also offer other coatings such as silver or gold for the IR range.  As a service feature we offer cleaning and a new coating of telescope mirrors. 


 
Quality Examination
A perfect shape and, at the same time, a very smooth surface are the characteristics of all Alluna telescope mirrors.
Each mirror is calibrated by interferometry and, depending on the mirror size, up to 10,000 points on the whole surface are analysed per software. For that purpose we use to the so-called compensation measurement also known as Ross Null test. Mirrors and RC systems up to a size of 24 inches (610 mm) diameter are calibrated in autocollimation against a high-precision flat mirror. 
Since we do not rely on one test only, we also use other tests such as Foucault, Ronchi, the phase-contrast test and others.
 
 
Oberflächen Bild
WaveFront Chart
Ronchitest am Stern
Alluna 25 Inch f3, 8 Mirror Ronchi recording directly
at the star with a 26 lines / millimeter Grid !

Ronchi in Autokollimation 10L/mm

Certificat Mirror

In case of the moon, the planets, disconnecting of close double stars and some planetary nebulae you will clearly see the advantages of a smooth surface structure both visually and photographically. In case of mirror telescopes it is particularly the smooth surface that significantly contributes to highest contrast and highest possible resolution. Compare Yourself


 
Quality Warranty
With a mirror of Alluna Optics give you one of the best currently available on the market Optics for the telescope. The production does not occur in a highly possible time but in the most profit potential optical Quality! We guarantee this and provide any look with a certificate and the original Interferogram.

The quality of our mirrors will convince you! For standard parabolic mirrors we guarantee surface accuracy better than 1/30 wave RMS at 632nm. For Ritchey Chretien systems, we guarantee a surface accuracy of 1/25 wave RMS / 632nm. Each Alluna mirror has a very smooth surface that is achieved by hardly any other manufacturer. Various test procedures guarantee consistent high quality.
 

20 inches Ritchey-Chrétien Telescope
30 Zoll Parabolspiegel Endkontrolle
30 inches parabolic Astro Sitall mirror


 
Alluna Ritchey Chretien Telescopes
Our Ritchey Chretien telescopes are real RC systems with a hyperbolic primary mirror and a hyperbolic secondary mirror. The optical design was developed for Alluna Optics by one of the best European specialists in this field. Every single mirror set is being manufactured and tested with extreme precision and care in our own production.
 


 


CNC manufacturing of tube Components
 

Upon developing the high-end RC OTA we have made no compromises. Precision and reliability were made the most impartant target during development and construction. All parts were optimised in advance with regards to weight, stability and expansion behaviour. All components for the carbon truss tube are made of special high-quality aluminium alloys and manufactured on most advanced CNC machines. With this procedure we achieve a very lightweight yet extremely stable and warp-resistant overall construction by means of a complex honeycomb-pocket structure. The accuracy of the milled aluminium parts lies at about 1/100 mm up to the 24-inches OTA. 
more about our Ritchey Chretien Telescopes 

 


 
Alluna Newtonian Astrograph
Same as the Ritchey Chretien telescopes our Newtonian Astrograph telescopes are also manufactured from the best material with most advanced methods. With every telescope you will receive a masterpiece of mechanics as well as the guarantee for a perfect optics. The same honeycomb pocket structure is applied for a light but highly stable and warp-resistant truss tube. All components are manufactured directly in our production plant or at partner companies. Only in case of the 3.5 inches feather touch draw tube we use am external product that is well proven in practice.
more about our Newtonian Astrograph Telescopes