We propose a colour-based technique for the visualisation of the phase of complex signals, in particular of Fourier transforms and of analytic signals. Using the fact that both the hue and the angle are cyclic magnitudes, a one-to-one relationship can be established between angles and colour hues that respects the cyclic order: an order isomorphism. With the help of a Matlab GUI tool, called a chromatic profiler, the correspondence is made so that the cardinal points [2] of the cyclic variables are preserved, and the rest of the points are mapped so that the result is best readable. What the technique may lack in accuracy is gained in readability.