Stellar (S) and eclipsing body (A) disks as seen from a pixel on the shadowed body during a penumbral eclipse. The stellar shadowed area is decomposed in two components A₁ and A₂. The angular radius of the bodies is represented by α_S and α_A, and δ is the angular separation between the bodies’ center. The central angles of the circular segments defined by the common cord of the intersecting stellar and eclipsing body disks are represented by θ_S and θ_A. The minimum distance from the star and eclipsing body centers to the common chord is defined as l_S and l_A, respectively.