A quadratic phase holographic lens can perform Fourier transformation on a two-dimensional input, but the transform is multiplied by a detrimental parasitic phase that is caused by the off-axis configuration. Fortunately, with the proper geometry, and for a limited spatial frequency, this parasitic phase can be considered as a constant, so it need not affect the Fourier transformation. We show how to set the frequency dependence ofthe parasitic phase in order to handle inputs with different spectrum characteristics, and how to choose the geometrical parameters of the system in an optimal way.