Telescope Mirror Coating Specifications

 

What We Offer

At Spectrum Coatings we strive for near perfection. A small business that cares about our customers. If you have any questions, please contact Paul Zacharias. Our best effort is put into each and every job that comes through our doors. We are dedicated to giving the amateur astronomer prompt service along with the most durable front surface mirror optical coatings available today. Rest assured that your mirror is in good hands. Your mirror is a precious object (we know because some of you are reluctant to even ship them!). Each one is handled with the utmost care. Don't worry about your optics, we have had many years of experience in stripping (old coatings), cleaning (prep for coating), and loading (the actual coating) of a countless number of telescope mirrors, as well as thousands of pieces of precision optics.When it comes to a durable, efficient, long lasting thin film, we are the best. Our Ion Assisted Deposition (IAD) is the state of the art in the optical coating industry. Our process for exceeds the MIL SPECS set forth for any of the military's optical coating requirements. Please see the Coating Technology section of our web page and then be fully convinced that the film applied to your mirror is one of the best front surface mirror coatings on the market today.Spectrum Coatings stands behind each product or service that we provide. Our policy is that if the customer is not completely satisfied we will re-coat the mirror at no charge to you (no shipping charges as well).

 

Coating Performance Specs:

Percent Reflection of (PAL) Protected Aluminum w/quartz (SiO2) overcoat.

Avg.(450-650nm)
450nm
500nm
550nm
600nm
650nm
90.6%±1%
87.6%
90.5%
91.6%
91.2%
90.5%

 

Coating Performance Specs:

Percent Reflection of Our (EAL) Regular Enhanced Aluminum overcoat.

Avg.(450-650nm)
450nm
500nm
550nm
600nm
650nm
96.48%±1%
95.77%
95.84%
96.85%
96.40%
95.77%

 

Coating Performance Specs:

Percent Reflection of Our MAX - "R"© EAL

Tried and thoroughly tested. This film is solid and stable. High contrast, low absorption and very durable. This is a modified enhanced aluminum coating. It is not a "pure dielectric" coating. One of the great benefits of this coating is it can etched like a normal EAL or PAL coating. Therefore, if the coating does fail you will not have to have the primary mirror polished to remove the film (unlike a dielectric coating). A pure dielectric coating has no metal layer, which means it cannot be etched off - it must be polished off which would require re-figuring the primary mirror. No one wants to do that! Front surface mirrors were once reserved for the laboratory, fragile and delicate - not with this coating. We have performed tests on all our coatings, tests that surpass the Government tests: Humidity, adhesion (actually pulled the adhesive off of a piece of 3M masking tape & a piece of 2" gray duct tape - not just cellophane tape like the government requires), abrasion and salt fog tests have not attacked the aluminum film that lies under these ion assisted deposited oxides. If it's not ion assisted, it's not a fully developed oxide. That is the bottom line.Please note that we do not offer the Max - "R" coating on any secondary mirrors. Most of our secondaries get coated with the Regular EAL coating.

Avg.(450-650nm)
450nm
500nm
550nm
600nm
650nm
98.27%±1%
97.00%
98.76%
98.81%
98.28%
97.03%

Mirror Handling Policy.