Selecting an Optical Filter

                            Attributes of a Hard Coat Filter

Optical Performance: Steeper slopes create a sharp transition from high peak transmission to deep OD4 blocking.

Resistance to the Environment: Hard coat filters are deposited on borosilicate glasses, making them suitable for high temperature as well as high humidity environments.

Longevity: Hard coated filters will last for decades under normal operationg conditions.

Surface Quality: Hard coat thin films are deposited on polished optical glass resulting in the best possible surface quality.

                  Attributes of a Soft Coat (Traditional) Filter

Optical Performance: UV to Near Infrared filters that block well beyond 1200nm.

Shelf Life: Andover runs extensive environmental and real worl testing on our soft coat filters, with demonstrated shelf life of up to 10 years.

Improved Optical Wavefront: Soft Coat filters can be corrected after lamination to create better than 1/10 wave (TWF). With no internal reflection, a corrected optic better than 1/4 wave TWF with a high efficiency A/R can be used in any imaging application including digital cameras and telescopes. Soft coat filters also have lower surface stresses, with less distortion.

Extended Blocking: Traditional filters can use metals in the coating designs to greatly extendtheir blocking ranges.

Larger Yields, Faster Process Means Lower Cost: Andover's advanced coating process handles larger batch sizes, with higher yields, in reduced time.

CONTACT US TODAY AND WE WILL HELP YOU MAKE THE RIGHT CHOICE FOR YOUR APPLICATION!