principal plane


Also found in: Dictionary, Thesaurus, Medical, Wikipedia.

principal plane

[′prin·sə·pəl ′plān]
(mathematics)
For a quadric surface, a plane that passes through the midpoints of all the chords perpendicular to it.
(optics)
Two planes perpendicular to the optical axis such that objects in one plane form images in the other with a lateral magnification of unity.
The vertical plane passing through the internal perspective center and containing the perpendicular from that center to the plane of a tilted photograph.

principal plane

A vertical plane that contains the principal point of an oblique photograph, the perspective center of the lens, and the ground nadir. It is the vertical plane containing the optical axis.
References in periodicals archive ?
The principal plane of symmetry of surface B is no longer parallel with the HB plane passing through the point G = -b/3a.
2] d lens thickness n refractive index Principal planes (VH): Front: [V.
Figure 11 compares the simulated and measured ARs against frequency in the two vertical principal planes ([phi] = 60[degrees] and [phi] = 150[degrees]) defined in the aforementioned section in n = 0 mode.
phi]]([psi]) are stored electronically, they can be post-processed to reconstruct the co- and cross-polarized components of the CP radiation pattern across that same principal plane cut.
8) and (9), the radiation patterns of the principal planes have been computed, and the results given by the AEP method and CST simulation are shown in Fig.
Good broadside radiation patterns with low cross polarizations (Less than 23 dB) are observed in the two principal planes.
Total far-field radiation patterns of electromagnetically modeled antenna (# 5), in both principal planes of [phi] = 0[degrees] (x-z) and [phi] = 90[degrees] (y-z), are obtained at its simulated resonant frequency of 5.
The radiation patterns of the antenna were measured in the principal planes at several frequencies in the cellular and GPS bands.
Radiation patterns of two principal planes [phi] = 0[degrees] and [phi] = 90[degrees] in simulation are depicted in Figure 8.
The radiation patterns in the three principal planes are plotted in Figure 4, for selected frequencies of (3, 5, 7.
The antenna is sensitive to both vertically and horizontally polarized waves and its radiation patterns have good isotropic characteristics in all the principal planes.