Request for source of coating polymer film

I have been looking for a product/manufacturer that exists because I have seen it but, for some reason, cannot be found anywhere in the USA nor does anyone know who can even make it.

Here goes .. I need ·

Optically transparent film · 4 mil in thickness ·

Anti-reflective coating but is able to reflect 30% of the visible light that strikes it to cut down on ghosting (along the i-line frequency) ·

Very low refractive index ·

Up to 4 meter wide rolls in any length

This will be used as a large HUD display for a show we are putting on. The film will be used like a large teleprompter.

Answer.

Let me start with some of the easier bits.

4m wide rolls.   This may be a problem. Specialised film tends to be manufactured in limited widths. The reason for this is the volume of manufacture. A large manufacturing machine produces a huge amount of product that all needs to find a home. With specialise film there tends to be a limited market and so volumes are small and so there is less justification to invest in a large machine.

This also applies to vacuum coating machines. The largest produced so far has been 4.45m width for a simple aluminium metallizer which runs a limited range of materials at high speed. The aluminium is deposited with a thickness of a few 10's nm with a uniformity of +/-10% or with additional shields +/-5%.

The optical coating you require is much more specialised and so requires multiple sources and this tends towards magnetron sputtering where the largest with is only around 3m, again for a single metal system or more usually less than 2m width for multilayer coatings.

Thus you may find it hard to source the polymer at 4m width, it depends if it can be made on the same manufacturing system as a higher volume material otherwise the width will be limited.  Once you have the film you may be further limited to the width of the vacuum coating system available.

My starting point would be to approach some of the expert vacuum coating companies.

Flex Products Inc (FPI) & Optical Coating Laboratories Inc (OCLI) who are both part of JDSU based in Santa Rosa CA are experts in designer optical multilayer coatings. OCLI have >20 years of designing specialist AR filters as used in many exotic applications and can model your optical requirements and what coatings you need to achieve the desired results.  I know they have experience in HUD technology. OCLI make small optical components whereas FPI are the flexible substrate division and operate the polymer film vacuum deposition roll coaters.

If you want a contact, the senior scientist at FPI is Roger Phillips  (Roger.Phillips@jdsu.com) who may be able to help you, if only to discuss through the problems.

FPI have to make money and so it may depend on the volume of material you want that determines the time they can spend on the project.

Most of the magnetron sputtering roll coating companies will have some form of the thin film modelling program that can predict the materials and coating thickness that would be required to give you the filter you require. They may also have the same quantity limitations that might limit the chances of getting the coating done.

An alternative strategy might be to use a narrower web width of a thinner material and laminate panels to make up the larger dimension final product. (just a thought)

Other vacuum roll coating companies that are worth contacting would include CPFilms ( hassan.memarian@cpfilms.com) or Bekaert Speciality Films (gary.phillips@Bekaert.com)

One other person to contact who may be a help to you and much closer to home would be Don McClure.  Don, until recently, was a senior scientist with 3M and is an expert on vacuum deposition and has worked on many optical coating products including AR's, controlled reflectance, filters,etc. He also has expertise in film manufacture and has a wealth of knowledge on speciality films such as low refractive index films.  He has set up a consultancy business since retiring from 3M (acuityct@hotmail.com )

If you make contact with any of these people I would welcome you letting them know that I have directed you to them so they can thank/blame me as appropriate.

I hope the above is of use.  If none of the contacts proves to be of use please feel free to come back to me and I will do what I can to help.