Re: Bizarre, but in the interests of science...
Sorry, but I must cry "Bollocks." Surrey satellites are protecting their chips from energetic particles (e.g. in the Van Allen belts around the earth); the protection from light could be accomplished by something much flimsier. My guess is that the packaging of the chop is to some extent permeable to UV or EUV light, with an energy (h*nu) similar to the work function of the semiconductor.
And by the way, lead make a terrible energetic particle shielding: it spells more secondary ions than it stops primaries. Indium or tantalum, that's yer stuff.