principal plane


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principal plane

A vertical plane which contains the principal point of an oblique photograph, the perspective center of the lens, and the ground nadir.
References in periodicals archive ?
There is a group of events which slips deviate from this principal plane. This phenomenon was referred many times e.g.
Figure 6 shows a classical geometry of a thick lens, a ray that enters the principal plane P and exits the principal plane P' at the same position with respect to the optical axis (however, generally not at the same angle) [18].
For each surface, the principal plane of symmetry is identified as the symmetry plane that aligns with, or runs parallel to, the G-or H-axis respectively; see Figures 3(d) and 4(d).
In either principal plane, the co-polarized patterns with and without DGS are found to be almost identical over [+ or -] 100[degrees].
Total visual arc, the angle of the principal plane and the visual angle were used to plot fields of view for B.
Three with the small circle for checking the NC controls (one for each principal plane), and six (two per plane) with the large circle to check machine geometry.
Although both A and B are now rotated relative to the GH axes, the orientation of the principal plane [X.sub.B][Z.sub.B] of the surface B is always rotated counter-clockwise by a constant angle n/4 relative to the principal plane [X.sub.A][Z.sub.A] of the surface A regardless of the values of the participating coefficients.
In this kind of antennas, the electromagnetic confinement mechanism within the horn relies wholly on the 3D EBG, which is flared in one principal plane; the antenna shows a typical sectoral horn pattern, with a directional beam in one principal plane and a broader beam in the other [29].
For CP antennas, the term principal plane can be defined simply as any slice or cut of the radiation pattern that passes through the peak of the main beam.
In contrast, the peak radiation still occurs in the two principal plane of [phi] = 0[degrees] and [phi] = 90[degrees] in n = +2 mode.
Figure 4 shows a comparison of the co-polar radiation patterns (principal plane) generated by the two models.
The elevation positioner (i.e., [theta]) was rotated from -180[degrees] to 180[degrees] with an increment of 5[degrees] for principal plane measurements.