IKAROS used this technique. The bird was spin-stabilised and a section of the sail had LCD shades that could be dark or light. It could darken its, say, venus-s

IKAROS used this technique. The bird was spin-stabilised and a section of the sail had LCD shades that could be dark or light. It could darken its, say, venus-side segments as they went round. Gloriously over-engineered.