Optimax currently provides 19 antireflection coatings for the Coating Library in OpticStudio. They can be divided into four categories, which are described below. The coating designs are encrypted, but this article will help determine which coating to select and how to evaluate its performance.
Authored By Jennifer Michels (Optimax Systems, Inc), Sandrine Auriol (Zemax LLC)
There are four classes of Anti-Reflection coatings provided by Optimax. The coating designs are available as encrypted coatings in OpticStudio.
Selecting an AR coating
To preview all of the coatings available in OpticStudio, click Libraries tab...Coatings...Coating Catalog. You can find the names of the available Optimax coatings in the encrypted coatings section, towards to the bottom of the catalog listing:
To apply a coating in your sequential design, in the Lens Design Editor go to Properties..Coating for the surface of interest. Then use the Coating drop down to select your coating.
To find out how to apply coatings to non-sequential objects please see to the article "How to add coatings and scattering functions to Non-Sequential objects".
Evaluating the coating
For an example of the use and performance of these anti-reflection coatings, refer to the file in the Article Attachments. This file contains singlet lens for coupling light between two single mode fibers and provides a useful example of how the application of coatings can affect the performance of an optical system. The front and back surfaces of the lens have an anti-reflective coating. Each configuration is a different coating and the screenshots below show how the coatings change the amount of light reflected at the lens faces. In addition, the merit function shows a comparison of the coupling between the different configurations and coatings.
Configuration 1 shows the lens when uncoated. The following image shows Reflection vs. Wavelength at the front face of the lens, but under Analyze...Polarization and Surface Physics...Coatings you can also access plots to transmission, absorption, phase, etc. vs. wavelength or angle.
Description of Anti-Reflection coatings
This is a single layer of magnesium fluoride, creating the simplest Anti-Reflection (AR) coating. The layer thickness is adjusted for the primary wavelength of the system (relative definition). The coating performance will also depend on the lens material. The coating design cannot be optimized for the lens material.
This coating is applied on Configuration 2:
These are V notch AR coatings, which are designed for a specific wavelength and are thus higher performing than the SLMGF2 layer. The design wavelength is xxx in nanometers. The design is further optimized for the lens material as indicated by the index of refraction 1.N, where N = nd. Select the index (nd) that most closely matches the substrate index. For example, if the design wavelength is 632.8 nm, and the lens is made of SILICA (nd = 1.46), the AR coating to select would be OPTIMAX-V633-1_46.
This coating is applied on Configuration 3.
These are Broadband AR coatings designed to perform over the wavelength range 400‐700 nm. The design is further optimized for the lens material as indicated by the index of refraction 1.N, where N = nd. Select the index (nd) that most closely matches the substrate index.
This coating is applied on Configuration 4.
These are Broadband AR coatings designed to perform over and extended range 450‐900 nm. The design is further optimized for the lens material as indicated by the index of refraction 1.N, where N = nd. Select the index (nd) that most closely matches the substrate index.
This coating is applied on Configuration 5.
The figure below shows a comparison between the different configurations.
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