Seeing of colored rings around bulb may be due to :
Conjunctivitis.
Cataract
Glaucoma - narrow angle
In conjunctivitis and cataract it may be of no significance but it may be early symptom of narrow angle glaucoma. Early diagnosis and treatment by Yag iridotomy , a minor procedure done by laser , prevents acute stage of glaucoma which is painful and may lead to loss of some eyesight.
Conjunctivitis.