An optical angular mapping for invariant optical/digital pattern recognition is presented using self-pumped phase conjugation followed by a vertical projection. In this method, the vertical contour features of an object are most enhanced and vertically projected at each angle as the object is rotated. The vertical enhancement of the contour and the projection are optically performed with self-pumped phase conjugation and a cylindrical lens, respectively. The peaks in the resulting projection at the angle are extracted and summed to produce an angular signature function. The signature function is then energy-normalized for scale invariance and pattern recognition is performed by calculating a crosscorrelation between two signature functions. The method exhibits invariance to shift, rotation, and variations in scale.