Integrated sphere for diffusal reflectance and transmittance

Claim 1

A hollow integrating sphere for reflectance spectroscopy formed within a substantially cubical block of diffusely reflecting hard sintered polymeric material having totally bounding planar external walls internally hollowed into a spherical and polished surface of the said material, and provided in one planar wall thereof with first aperture means for passing an external beam of light into the block, the block externally mounting a sample holder having a planar wall corresponding to the block planar wall at which it is mounted at one of the first aperture means and an oppositely disposed second aperture means for one of diffuse transmittance and reflectance measurements of the sample, and in which the polymeric material comprises at least one fluorinated aliphatic long chain addition polymer having at least one monomer wherein at least one fluorine atom is attached to a chain carbon atom being selected from the group consisting of polytetrafluoroethylene, polychlorotrifluoroethylene, polychlorofluoroethylene, polyvinylidene fluoride and polyvinyl fluoride.