The industrial production would inject the transparent shields to final shape, or extrude the curved profile and cut out the shields.
Here under are explanations for craft methods.
The bending process is adapted from bending thin wood. The tools must be optically smooth hence stainless and polished. Chromium or nickel layers should achieve that. Maybe silicone oil prevents adherence.
The glueing process needs few layers since the individual stiffness depends on the cubed thickness. Soft materials like paper can protect the sheets' smoothness.
A bubble-free glue layer hopefully results from pressing a drop or a line from the centre with training. Remove the protective films from the transparent sheets at last moment. MMA is runny, it polymerizes under a fluorescent lamp and binds PMMA perfectly, but it irritates the eyes brutally, so excellent air flow is mandatory. I succeeed with a similar process.
PC resists shocks and can make the deep layers, but detergents and hard objects damage it easily, so PMMA is preferred at outer layers. Maybe transparent sheets exist with anti-reflective coating.
A craft casting process may be possible too. It needs a mould with optically smooth big faces, curved in this case, normally made of glass, supposedly covered with an unmoulding agent. Silicone rubber can make the small faces. MMA is introduced, better from the bottom, and cured by exposure to a fluorescent lamp.
Marc Schaefer, aka Enthalpy