<prompt> Which of the following material is used in hard IOL?PMMASiliconHydrogelAcrylic  <response>: Ans. is a i.e., PMMA o Depending on the material of manufacturing, following types of IOLs are thereRigid IOLs Made entirely from polymethyl methacry late PMMAFoldable IOLs Are used after phacoemulsification and are made of silicon, acrylic, hydrogel and collamer.Reliable IOLs Ultra thin IOLs and are sued after phokonit technique micro- incision : 1mm. These are made of hydrogel 