Optical coating technology allows us to use Indium Tin Oxide (ITO) as a coating for optical components, to alter how they reflects and transmit light. One type of optical coating is an anti reflection coating.
ITO Coatings use low temperature vacuum depositing to make this highly conductive and transparent coating which can be applied to glass & plastic (acrylic, polycarbonate and polyester) substrates.
ITO is a highly conductive material that can be deposited onto various substrates to increase conductivity, whilst maintaining optical transparency.
Anti Reflective Optical Coatings
An antireflective or anti-reflection (AR) coating is a type of optical coating applied to the surface of lenses and other optical elements to reduce reflection.
In typical imaging systems, this improves the efficiency as less light is lost due to reflection. In complex systems such as telescopes and microscopes the reduction in reflections also improves the contrast of the image by elimination of stray light when using anti reflective coatings.
In other applications, the main benefit of using anti reflective optical coatings is the elimination of the reflection itself, such as a coating on eye glass lenses that makes the eyes of the wearer more visible to other people.
Applications of Optical Coatings
⦁ Beam splitters, often used in fluorescence microscopy
⦁ Front surface mirrors
⦁ Infra-red blocking filters (hot mirrors)
⦁ Bandpass and edge filters
Edge Filters
Edge filters can be used to reflect one portion of an incident spectrum and transmit another. Edge filters can be used as:
⦁ Cold mirrors, which transmit the infra-red portion and reflect the visible one
⦁ Hot mirrors, which transmit the visible portion and reflect the infra-red one. Hot mirrors are often used in the automotive industry. Early digital cameras were often sensitive to infrared radiation, producing contaminated colours. Insertion of a photographic hot mirror filter into the imaging pathway resolved this problem.
⦁ UV light filters
⦁ Colour filters
⦁ Narrow band filters
