Our IR Filters are deposited by  sputtering, using our ‘Rockard’ © technology, traditionally thermal evaporation has been used for IR filters.   Some of the benefits of sputtering are outlined below.

  • Highly durable coatings suitable for the toughest environments.
  • Extremely low temperature shift.
  • Reduced passband ripple for an even response.
  • High blocking efficiency to increase signal to noise ratio.

Sputtering Vs Thermal Evaporation

A brief overview of IR Filter deposition technology is outlined below. Sputter deposition has a process energy approximately 3x that of thermal evaporation, this is responsible for the densely packed structure. This structure leads to superior environmental properties as outlined below.

Traditional Thermal Evaporation

  • Voids in coating.
  • Poor environmental performance.
  • High shift with temperature change.

Open structure of traditionally evaporated coatings with gaps and voids.

Sputter Deposition

  • Voids eliminated.
  • Excellent environmental performance.
  • Extremely low temperature shift.

Densely packed sputtered coating with no gaps
or voids.

Look out for the Rockard Logo on products featuring our specialist technology.