Senior cat with eye issue

we noticed out senior cat Squiggly (hes 14) started having more eye crust than usual (He's always been a eye crust cat) and last night i noticed that hes has a weird reddish/whitish rings around his lids...im suspecting en infection or allergy to a new food....any one else think of what else it could possibly be?

Conjunctivitis, which needs to be checked out by a vet.