Having turned his back on agriculture Allen decided in 1957 to study art first at Worcester then Bath Academy of Art. Drawing inspiration from Adrian Heath and Gwyther Irwin whose lectures particularly interested him he began to experiment with various forms of abstraction. From 1960 Allen began concentrating on his own form of Op Art or Optical Art. This art form which focused on the use of optical illusions  was pioneered by himself, Bridget Riley, and Michael Kidner with whom he exhibited.  These early experiments with Op Art had a seminal influence on the artist and whilst his style changed  during his lifetime one can always see elemnets of early works.  After numerous exhibitions throughout the 60's and 70's  in 1975 his achievements were recognised with the solo show at the ICA, London which led to him gaining an international reputation with  further exhibitions in Europe Japan and the United States. Whilst Allen’s work was often geometric and formulaic as one would expect with Op Art there was an element of spirituality to his pieces that is integral to the artists messagefor as he said “I have never approached painting with the idea that there has to be a beautiful end product. If beauty can be said to exist in a work I would consider it more a by-product. I would prefer to think of it in terms of a spiritual experience for some people.”