Although I can't find the link to an article I read about the early development of PV cells using a purple glass filter I did manage to dig out a research paper

Although I can't find the link to an article I read about the early development of PV cells using a purple glass filter I did manage to dig out a research paper that provides more or less the same regarding colored filters https://web.archive.org/web/20220709132444/https://reader.elsevier.com/reader/sd/pii/S2214157X20303439?token=D712E898BFAB825FEF279C6C0AAFA3E60C4F6E537E003477BE578C2F76C138BCB8D65EE02F66AD7535CE4C79C2150B9F&originRegion=eu-west-1&originCreation=20220709132338 https://web.archive.org/web/20220709132444/https://reader.el... https://reader.elsevier.com/reader/sd/pii/S2214157X20303439?token=D712E898BFAB825FEF279C6C0AAFA3E60C4F6E537E003477BE578C2F76C138BCB8D65EE02F66AD7535CE4C79C2150B9F&originRegion=eu-west-1&originCreation=20220709132338 https://reader.elsevier.com/reader/sd/pii/S2214157X20303439?...