On Apr 14, 9:31 pm, Cecil Moore wrote:
Roy Lewallen wrote:
K7ITM wrote:
. . .
It's a useful visualization tool and design aid; it's a poor analysis
tool at best. At worst, it will lull you into building something that
just won't work, wasting time and resources.

In my opinion, the potential harm can be much worse. If it causes you to
buy into the notion that traveling waves interact in a linear medium,
that opens the door to a whole universe of invalid conclusions.

Here is how Hecht described interference in "Optics":
"... interference corresponds to the *interaction* of two or
more lightwaves yielding a resultant irradiance that deviates
from the sum of the component irradiances."

If traveling waves cannot interact in a linear medium, why
does Hecht say they do indeed interact?

It is exactly that kind of misleading terminology that has caused his
text to fall out of favor among many physics faculty.

To deny the body of laws of physics regarding EM waves from
the field of optics is an example of extreme ignorance.

You really aren't qualified to speak on behalf of the field of optics,
Cecil. You aren't quaified to speak on behalf of Eugene Hecht either,
for that matter. However, I think Dr. Hecht is still around so
perhaps you can persuade him to back you up. Be sure to ask him what
he thinks about the 4th mechanism of reflection.

ac6xg