I am very curious about those judges' dark glasses and what form they took.

I was trying to look into that myself and all the citations I could find kept circling back to Needham's Science and Civilisation in China. This page does the same, but adds that Chinese spectacles "were quite different than early spectacles from the West as they were made from rock crystal and were monoculars that could be attached together," which if true means the pair under debate cannot be an early model. It's not well-footnoted, though: it claims that the "tea lens" variant (what Needham transliterates as chha ching) were used as sunglasses proper and I can't tell if he has another source for that information or if he just disagrees completely with the paper on fire-pearls and spectacles that Needham is willing to believe partly. In short, I want more than the one book on the subject.