KBr viewports and Parylene coating

Torr Scientific offer a range of Infrared vacuum windows using a range of materials.  One such material is potassium bromide (KBr).  Under standard conditions KBr is a white crystalline powder, but it can also be manufactured in optical blanks which can be ground and polished into a variety of different optical shapes.

The history of KBr really begins in the 19^th century when it was used by the medical profession as an anticonvulsant and a sedative.  It was the first drug used to control epilepsy, but it had many side effects.  Nowadays better epilepsy treatments are available, but KBr is still widely used in veterinary practise to control epilepsy in dogs.

KBr was discovered to have a wide transmission range from the near ultraviolet (UV) to long infrared (IR) over a range of ~0.25µm to ~25µm, it also has no significant optical absorption lines in its high transmission region which has made it a useful material for IR spectroscopy.

On the downside, KBr is water soluble and therefore must be protected from moisture degradation of polished surfaces.  We therefore offer KBr optics protected by a Parylene C coating, which is highly effective against water vapour in a very thin coating and has very low outgassing.

If you would like to get more details, or request a quotation, please contact us at sales@torrscientific.co.uk