The Zeiss DT3/25/35 is based around the quite common 384x288 17um VOx just like the little variant of Leica Calonox (Sight version).
Here in Denmark the DTI3/25 & 35 goes for 2550 & 3125 euros, so a tad cheaper than Lecica's Calonox Sight variant which is around 4000 euros for the corresponding 384x288 17um variant.
Calonox is most likely Infiray sensor+lens but with custom image processing, Zeiss is 640*480 unlike Chinese sensors and i didnt see any monocular/sight with 20mm f1 or 40mm f1 lenses. Even more, i didnt see any 12m monocular with interchangeable lenses, users and servicemen will have much fun with dirt) their pdf brochure says sensors can be Vox or Asi, so maybe its newest ASi Ulis there.
upd: lens is German-designed, custom-made in China:
https://blogs.zeiss.com/sports-optics/hunting/en/faqs-about-zeiss-dti-6/