Fig. 1. Light path diagram and focal spot distribution of light through CPP and focusing lens. (a) Light path diagram; (b) focal spot distribution

Fig. 2. Filtering distribution of different focal spots. (a) Circle focal spot; (b) ellipse focal spot, e=0.64; (c) eccentric focal spot

Fig. 3. Histograms of surface gradient and far-field intensity of circular Gaussian focal spot. (a) Comparison of one-dimensional gradient histogram and normal distribution function; (b) two-dimensional gradient histogram; (c) light intensity ratio histogram

Fig. 4. Histograms of depth gradient and light intensity distribution for circular focal spots of different radii in the CPP surface shape. (a) Histogram of gradient distribution; (b) histogram of light intensity distribution at different radii

Fig. 5. Comparison chart of the horizontal and vertical gradients of the elliptical focal spot surface shape

Fig. 6. Comparison chat of the probability distribution of the surface gradient of elliptical focal spots under different ellipticities

Fig. 7. Probability distribution comparison charts of the surface gradient and the light intensity of different radii at different eccentric focal spots. (a) Gradient probability distribution diagram; (b) light intensity distribution at different radii

Fig. 8. Random wavefront distribution with different minimum spatial periods. (a) L=10 mm; (b) L=20 mm

Fig. 9. Comparison of the gradient distribution histogram and the far-field focal spots intensity proportion histogram at different radii under different random wavefronts. (a) L=10 mm; (b) L=20 mm