Obverse portraits
1933-1965
Over the years, the portrait on the coins has changed a number of times.  Here are some images of each, from selected coins:
George V King Emperor, is shown on all coins 1933 - 1936 (incl).
George VI King Emperor is shown on all coins from 1937 - 1947 (incl).
King George the Sixth, is shown on all coins from 1948 - 1952 (incl).
Queen Elizabeth the Second, is shown on all coins from 1953 onwards.
This is her first portrait, and doesn't change until decimal currency is brought in, in 1967.