Simulated lensed CMB temperature anisotropy map (top left), the amplitude of the difference of a simulated lensed and unlensed CMB temperature anisotropy map (top right), the amplitude of the simulated deflection field map (bottom left) and the lensing potential map (bottom right) with HEALPix pixelisation parameter N_side = 1024. These maps are obtained using the NFFT for the oversampling factor σ = 2 and convolution length K = 4.