We have considered a cholesteric elastomer slab whose thickness is smaller tan fifteen helix periods, immersed in a racemic solvent. We have calculated the reflectance and transmittance of obliquely incident circularly polarized light due to a cholesteric elastomer slab. We have found that even for such a thin slab there appears a regime of circular Bragg diffraction for certain values of the nematic penetration depth. We have also shown that for certain conditions on the solvent, the elastomer slab behaves as a universal filter. We summarize our work and address our conclusions.