Re: in laser guided bombs, the receptor/photodetector

On Feb 15, 7:17 pm, extremewanderer <ewu...@xxxxxxxxx> wrote:
On Feb 4, 2:00 pm, Alan Dicey <a...@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
wrote:





extremewanderer wrote:

 > No,no, ofcourse the light needs to be reflected.
 >
 > My question is;
 > Now, what if there was a method by which a spot of light which does
 > not need something to bounce off and is visible to the
 > receptor/photodetector that is installed on the bomb.

One or both of us is having problems with the language here:
you say

"No,no, of course the light needs to be reflected."
Then immediately below
"Now, what if there was a method by which a spot of light which does not
need something to bounce off"

Those two statements directly contradict one another.

 > Meaning the light is reflected & detected by the receptor/
 > photodetector without having to bounce off the target, without
 > needing something to bounce off.

reflection = bouncing off something.  Once again your statements
contradict themselves.

 > Pls see the diagrams below;
 >
 > Fig 1
 >  -------------------------------------------------------{}
 >
 >
 > In fig 1, dashed line is laser beam, the brackets represent the
 > target, the laser needs to touch the target and then bounce of in
 > order to be detected.

No.  No no no nyet he ne nej ei nem não (isn't google translation
wonderful?)

The laser does not need to be reflected off the target "in order to be
detected".
The laser must bounce off the target *in order to designate it as a target*
Wherever the laser spot is, the bomb will aim for.

 > Fig 2
 > ------------------------------------------------------O {}
 >
 >
 > In fig 2, dashed line is laser beam, the brackets represent the
 > target, the circle represents a spot of light in front of the target
 > which does NOT NEED TO TOUCH THE TARGET and then bounce of in order
 > to be detected.

Optically, the same case as Figure 1, exactly the same optical
situation.  The laser is now being reflected off the ground in front of
the target.  You are now designating a patch of ground as the target
rather than the tank, bunker or whatever.  If your bomb is big enough,
it may still work.

The "spot of light" in front of the target is the same as the spot of
light on the target produced in Figure 1, as far as the bomb is concerned.

...

Unless what you're trying to propose, in an elliptical fashion, is that
the bomb should offset its impact point from the designated spot.  The
main problem with this is that the bomb can't tell how far or in which
direction it should displace itself.  There are other optical issues too.

What I mean is that the laser beam is reflecting = bouncing off
without touching the target, and,with reference to, "The laser is now
being reflected
 off the ground in front of> the target.  You are now designating a patch of ground as the target
rather than the tank, bunker or whatever.", is not being reflected off the ground.,

All that is needed to reflect the laser is just air, only air.
As per the fig 2 below, the spot of light is hanging in air in front
of the target.

 Fig 2
  ------------------------------------------------------O {}

 In fig 2, dashed line is laser beam, the brackets represent the
 target, the circle represents a spot of light in front of the target
 which does NOT NEED TO TOUCH THE TARGET and then bounce of in order
 to be detected.- Hide quoted text -

- Show quoted text -

I know this sounds physically impossible, but it is not.
.

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