Optical orthogonal codes (OOCs) were introduced by Salehi, as signature sequences to facilitate multiple access in optical fibre networks. The existence of optimal (υ,3,1)-OOCs had been solved completely. Although there are some partial results, the existence of optimal (υ, 4, 1)-OOCs is far from settled. In this letter, three general constructions for (υ, 4, 1)-OOCs via perfect difference families are presented, new infinite classes of (υ, 4, 1)-OOCs are then obtained.