[Surabh K.t]

I have to measure the transmittance of a 6mm thick polycarbonate sheet.Should i use a film holder in this case or an integrating sphere?
Thanks in advance.

[P]

I am going to guess that it might not matter too much. As long as the UV path is blocked by sample at some point it will absorb/transmit in its range and you will get a spectrum, the sample holder should not really matter for a simple polymer film. I do not really know the full functionality of the integrating sphere though being honest, so I guess it would depend on what you are trying to do. Why would you need an integrating sphere?

[Corribus]

Integrating sphere is probably better in this case. 6 mm is very thick: not much light will make it to detector most likely.  Also there is scattering to worry about.

[Surabh K.t]

The main problem is the thickness. I really doubt whether film holders can take up samples upto 6mm thick.Integrating spheres can be used with uv spectrophotometers.They can take larger samples but they are not easily accessible.Moreover less number of people know how to operate uv spectrophotometers using integrating spheres.

[Surabh K.t]

Thanks for your help.

[P]

The main problem is the thickness. I really doubt whether film holders can take up samples upto 6mm thick.

A dollop of plasticine or blue tack would hold the plastic in place. It only needs block the ray.