Illustration of the pulsar viewing geometry in Cartesian coordinates using the angles of ζ = 25° and α = 35° in the magnetic frame. The magnetic axis is aligned with the z_b-axis, and the line-of-sight (LOS) and the rotation axis are indicated by the green and red arrows, respectively. Also drawn is the boundary of an open-field region (dotted gray), centered at the magnetic pole. The orientation is chosen so that the magnetic axis, the rotation axis and the line-of-sight all lie in the x_b − z_b plane at ψ = 0°. At this phase, the visible point is located at {θ_bV,  ϕ_bV}={6.7° , 0° }, as indicated by the blue dot.