Curious bicycle reflector incident

http://www.niquette.com/puzzles/cornrefp.htm

Cheers,

Carl Fogel

On Jun 15, 4:38*am, wrote:
http://www.niquette.com/puzzles/cornrefp.htm

And check out the solution to the puzzle at
http://www.niquette.com/puzzles/cornrefs.htm
The commentary by Myles Buckley on the solution, starting about
halfway down the page, explains very well why I so much like flashing
lights on my bike, front and rear, day and night.

Andre Jute
A little, a very little thought will suffice -- John Maynard Keynes
A good education helps too -- Andre Jute

On Jun 15, 9:35*am, wrote:

The same goes for Scotchlite that one should not overlook as a good
safety reflector. *What is more annoying are the many HID lights with
nearly collimated illumination that illuminate road signs poorly,
signs that are not in the middle of the traffic lane. *To make up for
that, these lights on cars and bicycles are blinding to oncoming
traffic until they are close enough that the collimated beam misses
the approaching observer.

That is mostly due to NHTSA and their unwillingness to adopt ECE
regulations for beam pattern for headlamps. The ECE lights have a
sharp horizontal cutoff with a kickup to the curb side to illuminate
roadside signs. I've been running them in my personal car for years
with no noticeable effects other than that I can see the road better;
I haven't noticed any inability to see overhead signs (most of which
are lit anyway) which is the usual argument put forward by NHTSA as to
why they are unacceptable.

Also, ECE codes mandate automatic levelers for HID lights (to
compensate for empty/loaded conditions) while NHTSA regs do not, only
making the problem worse.


You'll notice that they are most irritatingly blinding when still far
away and less so at close range... unless it is one of those bicyclist
who aim their light at oncoming observers to demonstrate their
powerful equipment, mostly in daylight... and how safely equipped.

To be fair, there's plenty of automobile owners that do that too. The
thing that I really hate is the cyclists (and motorcyclists too) with
strobing headlights, it's just annoying to look at. Not really
dangerous though unless poorly aimed. Of course some motorcyclists
leave their high beams on during the day, which can be painfully
blinding...

nate

wrote:
Carl Fogel wrote:

http://www.niquette.com/puzzles/cornrefp.htm

Cheers,

That item is interesting in a few ways. Unlike optical engineers, the
writer chooses to call a "cube corner" (trihedral) reflector, a
"corner cube" in a jargon that should include "shell eggs" instead of
"egg shells", or "tread tires" instead of "tire treads" as is common
in English for compound words. This is often a flag that something
else going on than rational discussion.

If you Google the terms "corner cube" and "cube corner" you'll find that
both are used to reference retroreflectors, but "corner cube" is the
more popular term. When I did laser interferometer application design
the term used was "corner cube".


Beyond that, the writer is apparently unaware that road signs, Botts
dot lane dividers, and spot reflectors, those 3-inch round, red,
yellow, and blue plastic reflectors in a two screw hole metal frame
use cube corners and serve well as safety devices. Overlooked is that
these cube corners do not have perfect 90° corners so they reflect a
diverging beam that does not go only back to the light source. If
that were not so, road markings wold not be visible in headlight
beams.

Indeed, that was the "solution" to the "puzzle". That the problem was a
"puzzle" reflects the author's unfamiliarity with optics more than
anything else.

These "gotcha" problems to me often reflect badly on the posers. In his
explanation he says: "The query in the puzzle calls for an explanation,
which will be elementary for a sophisticated solver who understands how
a Corner Cube works". So, the fact that he was surprised by the failure
of his retroreflector must be explained either by his "unsophistication"
at problem solving or his ignorance of retroreflectors. Presumably it's
the latter since he seems to regard himself a very clever fellow. If so
clever, why does he attempt to use things without a basic understanding
first? It's just plain vanilla ignorance on his part, which he also
presumes of his audience.

wrote:
Peter Cole wrote:

If you Google the terms "corner cube" and "cube corner" you'll find
that both are used to reference retro reflectors, but "corner cube"
is the more popular term. When I did laser interferometer
application design the term used was "corner cube".

Google is smart and knows that these backassward terms are used by
enough folks that they need search targets. It is the corner that
reflects and it is a cube corner into which light enters. When
working in retro reflectors, I was curious about the logic of the
reversed name given to the cube corner that is a trihedral corner.

Google isn't tagging these sites with synonyms, just indexing the text
they find as they crawl.

Apparently, "cube-corner" was the original term, but has been largely
replaced (even in technical books, and journals) by "corner cube". The
following abstract from 1987 is an example of the mixed use, presumably
the author used the more correct term in the body of the paper while
using the more popular term in the title so people could find the paper:

http://adsabs.harvard.edu/abs/1987SPIE..818..162F

"Retroreflector concepts - Corner-cube compared to catseye" -- Fuller,
Joseph B. C., Jr.

"A standard solid and open cube-corner retroreflector (CCR) is compared
with a catseye retroreflector (CER) in terms of field of view (FOV) and
expected wavefront errors."

It's not uncommon to see a paper using one term to reference one using
the other.

In article ,
wrote:

http://www.niquette.com/puzzles/cornrefp.htm

Yes.

--
Michael Press

aka Jobst Brandt wrote:
Carl Fogel wrote:

http://www.niquette.com/puzzles/cornrefp.htm

Cheers,

That item is interesting in a few ways. Unlike optical engineers, the
writer chooses to call a "cube corner" (trihedral) reflector, a
"corner cube" in a jargon that should include "shell eggs" instead of
"egg shells", or "tread tires" instead of "tire treads" as is common
in English for compound words. This is often a flag that something
else going on than rational discussion.

Beyond that, the writer is apparently unaware that road signs, Botts
dot lane dividers, and spot reflectors, those 3-inch round, red,
yellow, and blue plastic reflectors in a two screw hole metal frame
use cube corners and serve well as safety devices.

And found in your local hardware store at reasonable prices.

Overlooked is that
these cube corners do not have perfect 90° corners so they reflect a
diverging beam that does not go only back to the light source. If
that were not so, road markings wold not be visible in headlight
beams.

This is not new. AAA formerly made STOP signs of porcelain coated
steel signs using glass retro reflectors. These were the earliest
reflective road signs on our highways and are collector's items today.

http://sfbay.craigslist.org/nby/clt/1212893604.html

The same goes for Scotchlite that one should not overlook as a good
safety reflector. What is more annoying are the many HID lights with
nearly collimated illumination that illuminate road signs poorly,
signs that are not in the middle of the traffic lane. To make up for
that, these lights on cars and bicycles are blinding to oncoming
traffic until they are close enough that the collimated beam misses
the approaching observer.

You'll notice that they are most irritatingly blinding when still far
away and less so at close range... unless it is one of those bicyclist
who aim their light at oncoming observers to demonstrate their
powerful equipment, mostly in daylight... and how safely equipped.

Automotive HID lights are also very irritating when being tail-gated at
night.

--
Tom Sherman - 42.435731,-83.985007
I am a vehicular cyclist.

On 16 June, 04:25, Tom Sherman °_°
wrote:
aka Jobst Brandt wrote:



Carl Fogel wrote:

http://www.niquette.com/puzzles/cornrefp.htm

Cheers,

That item is interesting in a few ways. *Unlike optical engineers, the
writer chooses to call a "cube corner" (trihedral) reflector, a
"corner cube" in a jargon that should include "shell eggs" instead of
"egg shells", or "tread tires" instead of "tire treads" as is common
in English for compound words. *This is often a flag that something
else going on than rational discussion.

Beyond that, the writer is apparently unaware that road signs, Botts
dot lane dividers, and spot reflectors, those 3-inch round, red,
yellow, and blue plastic reflectors in a two screw hole metal frame
use cube corners and serve well as safety devices.

And found in your local hardware store at reasonable prices.



Overlooked is that
these cube corners do not have perfect 90° corners so they reflect a
diverging beam that does not go only back to the light source. *If
that were not so, road markings wold not be visible in headlight
beams.

This is not new. *AAA formerly made STOP signs of porcelain coated
steel signs using glass retro reflectors. *These were the earliest
reflective road signs on our highways and are collector's items today.

*http://sfbay.craigslist.org/nby/clt/1212893604.html

The same goes for Scotchlite that one should not overlook as a good
safety reflector. *What is more annoying are the many HID lights with
nearly collimated illumination that illuminate road signs poorly,
signs that are not in the middle of the traffic lane. *To make up for
that, these lights on cars and bicycles are blinding to oncoming
traffic until they are close enough that the collimated beam misses
the approaching observer.

You'll notice that they are most irritatingly blinding when still far
away and less so at close range... unless it is one of those bicyclist
who aim their light at oncoming observers to demonstrate their
powerful equipment, mostly in daylight... and how safely equipped.

Automotive HID lights are also very irritating when being tail-gated at
night.


Stick a couple of white cube corner array panels to a raincoat and
hang it on the back of your drivers seat.

On Jun 15, 8:19*am, wrote:
Peter Cole wrote:
http://www.niquette.com/puzzles/cornrefp.htm
Cheers,
That item is interesting in a few ways. *Unlike optical engineers,
the writer chooses to call a "cube corner" (trihedral) reflector, a
"corner cube" in a jargon that should include "shell eggs" instead
of "egg shells", or "tread tires" instead of "tire treads" as is
common in English for compound words. *This is often a flag that
something else going on than rational discussion.
If you Google the terms "corner cube" and "cube corner" you'll find
that both are used to reference retro reflectors, but "corner cube"
is the more popular term. When I did laser interferometer
application design the term used was "corner cube".

Google is smart and knows that these backassward terms are used by
enough folks that they need search targets. *It is the corner that
reflects and it is a cube corner into which light enters. *When
working in retro reflectors, I was curious about the logic of the
reversed name given to the cube corner that is a trihedral corner.

I suppose people also ride bike roads and bike mountains in that
sense.





Beyond that, the writer is apparently unaware that road signs,
Botts dot lane dividers, and spot reflectors, those 3-inch round,
red, yellow, and blue plastic reflectors in a two screw hole metal
frame use cube corners and serve well as safety devices.
Overlooked is that these cube corners do not have perfect 90°
corners so they reflect a diverging beam that does not go only back
to the light source. *If that were not so, road markings wold not
be visible in headlight beams.
Indeed, that was the "solution" to the "puzzle". *That the problem
was a "puzzle" reflects the author's unfamiliarity with optics more
than anything else.
These "gotcha" problems to me often reflect badly on the posers. *In
his explanation he says: "The query in the puzzle calls for an
explanation, which will be elementary for a sophisticated solver who
understands how a Corner Cube works". *So, the fact that he was
surprised by the failure of his retro reflector must be explained
either by his "unsophistication" at problem solving or his ignorance
of retro reflectors. *Presumably it's the latter since he seems to
regard himself a very clever fellow. *If so clever, why does he
attempt to use things without a basic understanding first? *It's
just plain vanilla ignorance on his part, which he also presumes of
his audience.

I don't see it as a puzzle as the writer apparently wanted to make it
seem. *I guess he once looked into a laser surveyor's target and saw
only his own eye regardless of how he moved his head.

Jobst Brandt- Hide quoted text -

- Show quoted text -

Thank you for recommending that I should change the expression "corner
cube" at...

http://niquette.com/puzzles/cornrefp.htm

....to the argot of the optical engineer, "cube corner."

A Wikipedia search on "corner cube" turns up...

http://en.wikipedia.org/wiki/Corner_cube

....and a search on "cube corner" turns up no article by that name.
Perhaps you will offer an expert change via the discussion page,
which is currently blank.

Excuse me for wincing, but it is hardly collegial to imply "...that
something else [is] going on than rational discussion." Try humor.
And a satirical illustration of “Perfection est l’enemie du bien.”

Perhaps the calendar plays a part in the mystery. The self-
deprecative narrative describes events that occurred in 1972, which
possibly pre-dates the terminology as applied to both "Botts dots"
and "Scotchlite." You are invited to do the research on that.

Meanwhile "corner cube" is the only expression I have ever heard as
a synonym for "retro-reflector," beginning with my staff
responsibilities at Electro-Optical Systems in Pasadena during the
Apollo Program.

Best regards,
Paul Niquette

P.S. The "Corner Cube" puzzle has been quite popular, with most
people expressing appreciation for the graphic-intensive explanation.

hibike wrote:
On Jun 15, 8:19 am, wrote:
Peter Cole wrote:
http://www.niquette.com/puzzles/cornrefp.htm
Cheers,
That item is interesting in a few ways. Unlike optical engineers,
the writer chooses to call a "cube corner" (trihedral) reflector, a
"corner cube" in a jargon that should include "shell eggs" instead
of "egg shells", or "tread tires" instead of "tire treads" as is
common in English for compound words. This is often a flag that
something else going on than rational discussion.
If you Google the terms "corner cube" and "cube corner" you'll find
that both are used to reference retro reflectors, but "corner cube"
is the more popular term. When I did laser interferometer
application design the term used was "corner cube".
Google is smart and knows that these backassward terms are used by
enough folks that they need search targets. It is the corner that
reflects and it is a cube corner into which light enters. When
working in retro reflectors, I was curious about the logic of the
reversed name given to the cube corner that is a trihedral corner.

I suppose people also ride bike roads and bike mountains in that
sense.





Beyond that, the writer is apparently unaware that road signs,
Botts dot lane dividers, and spot reflectors, those 3-inch round,
red, yellow, and blue plastic reflectors in a two screw hole metal
frame use cube corners and serve well as safety devices.
Overlooked is that these cube corners do not have perfect 90°
corners so they reflect a diverging beam that does not go only back
to the light source. If that were not so, road markings wold not
be visible in headlight beams.
Indeed, that was the "solution" to the "puzzle". That the problem
was a "puzzle" reflects the author's unfamiliarity with optics more
than anything else.
These "gotcha" problems to me often reflect badly on the posers. In
his explanation he says: "The query in the puzzle calls for an
explanation, which will be elementary for a sophisticated solver who
understands how a Corner Cube works". So, the fact that he was
surprised by the failure of his retro reflector must be explained
either by his "unsophistication" at problem solving or his ignorance
of retro reflectors. Presumably it's the latter since he seems to
regard himself a very clever fellow. If so clever, why does he
attempt to use things without a basic understanding first? It's
just plain vanilla ignorance on his part, which he also presumes of
his audience.
I don't see it as a puzzle as the writer apparently wanted to make it
seem. I guess he once looked into a laser surveyor's target and saw
only his own eye regardless of how he moved his head.

Jobst Brandt- Hide quoted text -

- Show quoted text -

Thank you for recommending that I should change the expression "corner
cube" at...

http://niquette.com/puzzles/cornrefp.htm

...to the argot of the optical engineer, "cube corner."

A Wikipedia search on "corner cube" turns up...

http://en.wikipedia.org/wiki/Corner_cube

...and a search on "cube corner" turns up no article by that name.
Perhaps you will offer an expert change via the discussion page,
which is currently blank.

Excuse me for wincing, but it is hardly collegial to imply "...that
something else [is] going on than rational discussion." Try humor.
And a satirical illustration of “Perfection est l’enemie du bien.”

Perhaps the calendar plays a part in the mystery. The self-
deprecative narrative describes events that occurred in 1972, which
possibly pre-dates the terminology as applied to both "Botts dots"
and "Scotchlite." You are invited to do the research on that.

Easy, both products were widely available long before 1972 (although I
don't know what that has to do with anything).

Meanwhile "corner cube" is the only expression I have ever heard as
a synonym for "retro-reflector," beginning with my staff
responsibilities at Electro-Optical Systems in Pasadena during the
Apollo Program.

A brief browse should acquaint you with the uses of both terms,
shouldn't take more than 10 minutes, even for a slow reader.


Best regards,
Paul Niquette

P.S. The "Corner Cube" puzzle has been quite popular, with most
people expressing appreciation for the graphic-intensive explanation.

Even with optical engineers?