On this slide we have the intersection with the ray and the focal plane on the x-axis, and ray and aperture plane on the u-axis.
This slide is telling us that normal 2D cameras capture the irradiance which is the integral of all light intensities from all rays that cross the u-plane. That's why there's a vertical bar on the right, representing the sum across all u-values.
On this slide we have the intersection with the ray and the focal plane on the x-axis, and ray and aperture plane on the u-axis.
This slide is telling us that normal 2D cameras capture the irradiance which is the integral of all light intensities from all rays that cross the u-plane. That's why there's a vertical bar on the right, representing the sum across all u-values.