I do not know of any. It is usual to use a metal mesh, with holes much less than half a wavelength across. If you want just a small window,to send a laser beam in, for example, a metal tube a quarter of a wavelength across and several wavelengths long would be fine. Look up cut-off waveguide (circular or rectangular) and transparency of metal meshes as a function of hole size and spacing.
It all depends on the frequency you are talking about. As Malcom pointed out, metal meshes work fine for RF, but lower frequencies are much more complicated, magnetic shielding is also an issue, people usually employ ferrites (high permeability).
As frequencies go up its easier to provide a shielding, aluminum foil is a good example, it effectively blocks higher frequencies, in spite of being very thin. Its got to be thicker (3 x) than the skin depth for that particular frequency.
There are many good books on that, take a look into Ott, Electromagnetic Compatibility Engineering.
If you really need transparency as of "glass": ITO (Indium Tin Oxide). That's the material the conductors on resistive touch screens and some other things are mode of. But you will find it difficult to find a way of depositing it on a "random" surface.
IIRC, very thin layers of aluminum or even copper might work too. Deposited via PVC or CVD - very much like the deposition of ITO.
OK - all these coatings are of limited shielding efficiency. As layer thickness increases, transparency decreases. What we are talking about are layer thicknesses in the nm (nanometer!) range.
Aside from that: wire mesh. See the answers of the esteemed colleagues.
thank you for your answer and help. I would like to explain more about this issue. I try to design a shield for windows, clothes, and ....for the frequencies between 1 to 5GHz and up to -25dbm damping. It Should be flexible and transparent like ruching clothes. what materials are good solutions for this purpose? and how it should be designed and constructed?
Like ruching clothes ? Check for woven metallized fabrics! These are either fabricated with metallized fibers of with interwoven wires.
I know such fabrics are available... Search for "Abschirmgewebe" (I hope, these pages have also an English version) of "shielding fabric", "shielding netting" and alike. According to a short search of mine, your attenuation requirements should be fulfillable. The remaining "issue" will be how to ground your fabric as full efficiency requires grounding the shield.
Regards
It is not so much grounding but continuity that matters.If the mesh doesn't make good contact at the edges of a window frame (will it be metal anyway?) then there will be leakage round the edge. With clothes, contact between different articles of clothing will affect the shielding. It may be possible to build chokes into the edges of the mesh (probably challenging but maybe not impossible) that will reduce leakage where there is not contact between adjacent panels. See microwave oven door chokes, then work out how to make that work in thin fabric!
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