Mike Kaliski wrote:

...
It is only when looking at the exact edge of the antenna that any
appreciable drop in light out put will be noticed. At all broadside
angles an appreciable amount of light would be seen. The same effects
can be expected to occur at RF but the majority of amateur test
equipment would not have the resolution to measure the dip with the
antenna edge on. The width of the receiving antenna and diffraction
effects would tend to hide this in the far field, and alignment,
reflection effects and manufacturing tolerances in the near field.
...
Mike G0ULI

The eye, like the ear, has defects, in the fact it is not linear.

However, if a ribbon the width and depth of a razor blade is white hot,
a light meter available and rotated around this ribbon--the least energy
would come from the side, the most from the flat. There would be
something of a linear graph in the 90 degree rotation between thinnest
to broadest ... please, don't attempt to kid a kidder.

Regards,
JS