The present invention discloses to a high refractive index polysiloxane
(co)polymer comprising refractive index modifying groups chemically
bonded in clustered configuration to the polysiloxane backbone. The
invention also discloses methods for the preparation of such high
refractive index polysiloxane (co)polymers. A polysiloxane according to
the invention is very suitable for use as a material for the production
of intra-ocular lenses.