Abstract
We have carried out high resolution spatial measurements of the surface reflectance and responsivity of single and trap-configured silicon photodiodes at laser wavelengths between 325 nm and 780 nm. The results indicate that the spatial nonuniformity of quantum efficiency for a given photodiode varies with laser wavelength and internal structure. For radiometric quality diodes this nonuniformity of response leads to uncertainties in detector measurements which can be reduced to 0,03% or better.