I recently wrote a quick overview of the new Carl Zeiss Victory HT Binoculars that were soon to be released in Australia. One of the things evident in the press release is that the biggest step up is going into the new HT Glass. After further reading on this HT Glass from SHOTT, I found out some interesting information.
SCHOTT is no stranger to Sport Optics or Telescopes. Their glass is extensively used in premium Telescopes from Takahashi and SYNTA Skywatcher for many years. Founded in Germany by Otto Schott, SCHOTT AG have been developing and manufacturing special glass, components and systems to improve how people live and work for more than 125 years. Their contribution extends to not just Telescopes and Binoculars but various other Optics as well.
SCHOTT HT Glass
Optical Glass with Ultra High Transmittance
As mentioned countless times, no glass (or Mirror) can transfer 100% of the light hitting it. A percentage is lost due to absorption, stray reflection. This percentage varies between binoculars, obviously, the cheaper the binoculars, the lower the transmission.
SCHOTT has recently developed this HT optical glass that has significantly improved transmittance levels. This was not designed exclusively for Zeiss and we expect to see it in various optical systems such as Telescopes or other premium Optics Products. Currently, eleven of these special versions exist and are marketed as HT or HTultra. It can be safely assumed that they are working on more offerings and expanding this into as many categories as possible.
Improved Color & Image Quality
According to SCHOTT, Mesopic Vision has been optimized – this is your vision in vision in low but not quite dark lighting situations. Due to this, the image quality and also how vividness has improved, this is a given due to the exceptionally high light transmission.
Reduced Thermal Blooming
Moreover and according to SCHOTT, the “thermal lensing effect” has also been reduced through lower absorption of energy. This means that when a narrow beam shines through the glass, a small amount of the incident energy is locally absorbed. This heats the glass slightly which causes the refractive index of the glass to change, this can affect how the light exits the glass and also the quality of the image.
So there you have it, the overview of this amazing SCHOTT HT Glass. To keep costs low, optics manufacturers often share components or outsource them to specialist manufacturers like SCHOTT. We’ve seen this done via OEM Binoculars by Celestron and Barska, SYNTA Telescopes being made as Skywatcher and various other brands and much more. Binoculars would probably be the most consumer oriented product you will see this glass in. SCHOTT expects to use this in high-end Projectors, Industrial Optics products and other specialist applications.