The Thin-film Software RP Coating for the Design of Optical Multilayer Structures: Laser Mirrors, Anti-reflection Coatings, Edge Filters, Thin-film Polarizers, Etc. (original) (raw)

RP Coating – Advanced Software for Designing Optical Multilayer Structures

Simulate all relevant coating features,
reach best performance!

RP Coating V4 is a particularly flexible and powerful thin-film software tool for developing all kinds of optical multilayer structures. It is not limited to a range of standard devices as conceived by the software developer, but also gives the developer the power to analyze and optimize anything new. At the same time, it is extremely convenient for industry people who often need to quickly adapt optical coating designs to new parameter values: designs can be fully parameterized such that the whole structure can be controlled with a few parameters instead of a long list of layer thickness values. That can be particularly useful for numerical optimizations.

Essentially, a thin film coating design is characterized by a sequence of material layers (with known optical properties) and the corresponding film thickness values. While it is relatively simple to analyze the optical properties of a given design, it can be challenging to find designs with optical properties suitable for specific applications, fulfilling certain specifications. To some extent one can work with numerical optimization, but it is often helpful to begin with some conceived type of design where not too many parameters need to be optimized. Here, it is vital to have (a) a flexible and powerful software and (b) competent and helpful technical support. That way, you can efficiently design thin film coatings for many applications.

Start with Simple Forms

With the software we provide various demo files for different kinds of thin film coatings, containing handy custom forms, with which you can very easily get started. See examples of a Bragg mirror and a GTI mirror:

When executing the calculation, you get various diagrams (not shown here), showing both the resulting thin-film design (possibly involving a numerical optimization) and the resulting essential optical properties. You can also get outputs displayed in the form itself. Further numerical outputs can appear in the output area on the right side.

A great feature is that those forms and calculations are not hard-wired: you obtain script files, in which you can easily modify the forms and calculations according to your specific needs! For example, you may introduce more parameters to the design, create additional diagrams or numerically display additional optical properties of the thin film design. And in case that things are getting too difficult for you, you will get very helpful technical support. You can get even complete new scripts made according to your informal description of what you need.

The Product Brochure

You can download our brochure in PDF format.

Design Anything You Need!

RP Coating can be used, for example, to analyze and optimize the following kinds of thin-film devices:

• dielectric mirrors (laser mirrors), including chirped mirrors (e.g. most advanced double-chirped mirror designs with extremely high bandwidth) or other kinds of dispersive mirrors (e.g. GTIs)
• anti-reflection coatings, including advanced multilayer structures, found e.g. with a Monte-Carlo technique
• optical filters (short-pass and long-pass edge filters, band-pass filters, monolithic and air-spaced etalons, volume Bragg gratings, rugate filters and other types of interference filters)
• thin-film polarizers (plate polarizers, polarizing cubes)
• semiconductor structures, such as SESAMs, including saturable absorption characteristics, chromatic dispersion, etc., and also VECSEL gain structures

You may also define any other multilayer structures, for whatever purpose.

Main Features

• RP Coating offers different methods to define a thin-film multilayer structure. Apart from simply listing all layer materials and thickness values one by one, it is also possible to specify a structure with mathematical expressions (e.g. to calculate a chirped mirror structure according to a few given parameters). This allows you to fully parameterize your designs: you can control the whole design with a couple of parameters instead of a long list of layer thickness values, and also do at least a preliminary numerical optimization with those parameters only. Another option is to read a structure from a file – with great flexibility concerning binary and text file formats.
• The program can calculate a large number of relevant properties of a multilayer design, including its reflection and transmission amplitudes and phases (with a variable angle of incidence), chromatic dispersion, field distribution inside the structure, etc.
• There are material data for a substantial selection of materials. It is also no problem to add data for any additional materials, using essentially any kind of definition: tabulated data (refractive index versus wavelength), a Sellmeier formula or whatever may be more appropriate.
• The software allows for various kinds of design optimizations. A figure of merit can be freely defined as a mathematical expression which may refer to arbitrary combinations of different properties, including fabrication error tolerances. (Note that competing products normally only allow you to modify parameters of a fixed type of figure of merit.) The optimization can be a local one or use a Monte-Carlo algorithm. It can affect all layer thickness values separately, or only some parameters which indirectly determine a layer structure.
• By fitting to experimental data, deviations from specified thickness values or material data can be calculated.
• All results can be shown graphically. The user can essentially define any kind of plot or color diagram, and not only select from a set of predefined diagrams.
• Also, results can be shown in text form: written into a special area in the software window, written into graphical diagrams or to text files. There is full flexibility concerning text or binary file formats. For example, you can read files from a spectrometer and write files for controlling your coating machine.

You will hardly find a competing software which is similarly flexible and suitable for such a wide range of applications!

More than 15 demo files are delivered the software, treating simple mirror structures as well as sophisticated optimizations. If you need more specific examples, you can get them within the technical support.

If you have any further questions or need a quotation: Contact us