English scholar who wrote on practical applications of optics, as well as on other scientific subjects. A member of the Franciscan order, Peckham taught at Oxford and later Rome before becoming archbishop of Canterbury in 1279. In his scientific writing, most notably his Perspectiva communis, he showed the influence of Ibn al-Haytham (Alhazen; 965-1039) and Witelo (c. 1230-1275). During the fourteenth century, the writings of Peckham and Witelo gained a much wider audience than those of Roger Bacon (1213-1292) with regard to optics. It would only be in the mid-sixteenth century that scholars took a new interest in Bacon's work on the subject, which, as it turned out, offered much more promise with regard to development of optical instruments.