True, but the pcb was actually just an example.
A better example was the paper, a black piece of paper,
under it a paper with printing on and again a black paper.
Light cannot go through, so what method to use to see
the print on the white paper without tearing the layers
apart?
This was a question of someone i know, he needs such
application in his factory, it has something to do with
fraud detection.
I cannot say exactly what, only that the above example
comes very close to what he needs.
Can infrared penetrate cardboard?
I would say there must be a way to do this.
Bart Bervoets
"Jerry G." schreef in bericht
...
The only way to do this, without delaminating the boards are with the use
of
X-Ray equipment. Then there is the task of deciphering what you see. IR
will
be of too long a wavelength for any type of detail, and is of heat in
characteristics. UV is a very short wavelength of light, but does not
penetrate or pass through many types of materials. UV would not be
visible,
and is difficult to decipher in visual detail.
A manufacture called Golden Engineering can make the type of X-Ray
equipment
required for this type of application.
http://www.goldenengineering.com/ shows a X-Ray machine that would most
likely do well with circuit boards. This one see several inches square at
a
time. A photo plate is required below the search head. There are some
very
large systems that can show the output on to monitors, or computers.
http://www.goldenengineering.com/xr150.pdf shows their smallest model. It
can penetrate 1/2 inch of steel. I am sure that this unit would do what
you
want.
For general service work, this type of industrial X-Ray equipment would be
prohibitive. You can put a nice down payment for a home, or even go out
and
by a new car for the cost of the basic unit. These are normally purchased
for industrial applications. Their application is usually for flaw
detection
inside of materials. An example would be, critical aircraft and auto parts
are X-Rayed for safety checks during their manufacture and production
process.
As far as service is concerned, I know what you are getting at. It is far
cheaper to replace a complete circuit board, or to sell the client a new
set, rather than spend many hours on it, and change a lot of parts. This
is
especially true for the low to medium end consumer units. This is why many
manufactures do not have the sales info-structure in place to sell the
parts
or service manuals. Many of them do not even publish service manuals for
distribution. The schematics stop at the manufacture level. Manufactures
who
sell the service manuals for their products, would never provide the
circuit
board layout design information. This would make it easier for their
competitors to reverse engineer their products.
--
Greetings,
Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================
"Bart Bervoets" wrote in message
news
Is there any way to "look through" a circuit board which
has traces inside (multilayer)?
I tried making the layers visible with a lighttable, but
the board is simply not thick enough to let enough
light pass.
Any other way to look inside a board or other object?
I thought of infrared light, but no idea how to make that
visible on the other side.
This sounds strange, i know, the circuit board is just an
example, another example may be, how to show the
metal in security cards, bank notes, check for printing
under a label without removing the label, and so on.
A third example may be, i have 2 pieces of black paper.
inbetween i put a piece of newspaper.
Light should not pass, but is there a way to make the
text visible?
Again, sounds weird, i know, but i have a good reason
for it.
As well, can electric current in a board made visible ?
To check for broken traces, continuity problems, and
so on.
Someone claimed he did all above but refuses to say how,
but i know he uses a computer scanner and something on
top of the object, thatīs why i thought of infrared.
Any ideas?
Bart Bervoets