
I Just Poured Water on my Scanner - protomyth
http://www.cpushack.com/2015/03/29/i-just-poured-water-on-my-scanner/
======
tyho
I remember having to use special oils to use some high magnification
microscope lenses in a process known as 'oil immersion microscopy'. I didn't
read much about how it worked before but I assume it is the same process.
There was no other way for me to get the magnification I needed to count the
reletive number heterocyst cells in strands of cyanogenbacteria for my biology
coursework.

I would suggest to the author that they buy some microscopy oils as they will
have a higher refractive index to water.

[https://en.wikipedia.org/wiki/Oil_immersion](https://en.wikipedia.org/wiki/Oil_immersion)

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symmetricsaurus
If the scratches are on the glass it could work even better to use a liquid
with the same refractive index as the glass. That should make the scratches go
away completely.

One option is glycerin as can be seen in this video:
[https://www.youtube.com/watch?v=pNWCB_GoQA4](https://www.youtube.com/watch?v=pNWCB_GoQA4)
(maybe it only works with pyrex glass ?)

Another option is to mix to fluids together, one with a higher index of
refraction and one with lower. That way you can tune it to your particular
scanner (although I would think most are the same).

How you see if your mix has the same refractive index as the glass I haven't
figured out yet.

~~~
laxatives
Similarly, you can scrub some scratched up glasses with toothpaste to fill in
the air gaps. Good as new (at least until it rains).

~~~
evan_
That doesn't work the same way, that polishes the edges of the scratches so
they're not as distinct.

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Animats
Clickbait title, of course.

For film scanning, this is known as a wet-gate transfer.[1] It's standard
procedure for digitizing old cine film. The working fluid used has the same
index of refraction as the film backing, so scratches disappear.

The guy who's photographing ICs just needs a toy-grade digital microscope.[2]

[1]
[http://www.arri.com/archive_technologies/archive_challenges_...](http://www.arri.com/archive_technologies/archive_challenges_and_solutions/arri_solutions/wet_gate/)
[2] [http://www.amazon.com/ThinkGeek-P510002-Digital-Blue-
Microsc...](http://www.amazon.com/ThinkGeek-P510002-Digital-Blue-
Microscope/dp/B000059TF3)

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nmc
As the article points out, this is not a new technique. Increasing your
resolving power by immersion of the target object in a liquid medium is
actually used in ICs manufacturing.

This is because resolving power is directly proportional to numerical
aperture, which is in turn proportional to the refractive index of the medium
between the imaging device and the target object.

As a result, it works both ways: you can use it to increase resolution while
_either_ sending _or_ receiving beams of light. For instance, the same
technique is also used in light microscopy.

In the end, this is a clever and straightforward hack.

~~~
spystath
You are talking about immersion lithography. It replaces the air gap from the
final lens of the lithography system with water which has greater IOR. AMD has
been using it for a while, probably before the 45 nm node. Strangely enough
Intel was not using it until the 32 nm node. It's the same hack with oil
immersion lenses, basically, for the optical microscopes.

~~~
dzordzduan
If you didn't watch this video before...
[https://youtu.be/NGFhc8R_uO4?t=15m50s](https://youtu.be/NGFhc8R_uO4?t=15m50s)

~~~
deckar01
This is a great presentation on the evolution of transistor manufacturing
processes. I didn't know how a transistor worked before watching this video,
yet was engaged by the technical narrative of the semiconductor industry
overcoming one physical constraint after the other.

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Brian-Puccio
Fluid mounting things to scan them is something that photographers have been
doing for a while. The higher-end Epson flatbed scanners (which is really a
low-end film scanner) have fluid mount options [0] while fluid mounting for
drum scans [1] (high-end film scanners) is the norm unless you get a flexframe
model from Hasselblad which doesn't use glass (so no need for a fluid). Plus
wet mounting your scans helps with the Newton rings issue.

[0]
[http://www.photo-i.co.uk/Reviews/interactive/Epson%20V750/pa...](http://www.photo-i.co.uk/Reviews/interactive/Epson%20V750/page_7.htm)
[1]
[https://www.youtube.com/watch?v=aCHS5yiF4Mc](https://www.youtube.com/watch?v=aCHS5yiF4Mc)

~~~
dietrichepp
I'm not convinced that the flextight (talking about what used to be Imacon,
right?) options are a complete substitute for wet mounting, because wet
mounting will reduce the appearance of scratches on the film itself, but
eliminating the glass doesn't fix that particular problem.

~~~
Brian-Puccio
I'm sorry, I should have posted more clearly. Yes, you will reduce film
scratches (and Newton rings and glass scratches) if you wet mount. You will
only reduce Newton rings and glass scratches if you use an Imacon/Hasselblad
since there is no glass to scratch or produce Newton rings. So, yes, I do
think that a wet mounted drum scan will still get you the best quality.

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aepearson
This is super common amongst film photographers - it's a wet scan. Works
wonders. Some of the fanciest "drum" scanners out there work this way
exclusively.

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patcheudor
"The markings are laser etched directly onto the surface of the silicon die."

That's the package, not the silicon die.

~~~
Gracana
It's both! [http://i00.i.aliimg.com/wsphoto/v0/1639827880/Free-
shipping-...](http://i00.i.aliimg.com/wsphoto/v0/1639827880/Free-
shipping-5PCS-QG80331M500-SL9BE.jpg)

~~~
Gracana
Assuming someone downvoted because they didn't understand or felt I didn't
explain enough... That chip in the picture (the intel QG80331M500, the chip in
question) is a flip chip package; instead of using wire bonds to connect to
pads on the die, it has solder balls like a BGA package. The chip is soldered
down to a carrier PCB and an underfill glue/sealant is applied around it, so
the only thing exposed is the bare back of the die. There is no plastic
package to laser-engrave, the engraving is done right on the silicon.

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Tloewald
I was hoping to see scans of the actual silicon, but I guess that requires
more exotic equipment. It seems to me that imaging the chips would be easier
and better using a DSLR and a good macro lens.

~~~
zokier
Zeptobars has some nice shots of silicon dies. As a random example
[http://zeptobars.ru/en/read/Nordic-NRF24L01P-SI24R1-real-
fak...](http://zeptobars.ru/en/read/Nordic-NRF24L01P-SI24R1-real-fake-copy)

I estimate that those images are taken with equivalent of about 60000 DPI.
Even with that sort of resolution you can't really resolve the details in the
smaller features.

In comparison typical macro lenses have 1:1 magnification, so e.g. D800 DSLR
with 36MP sensor would have theoretical maximum of roughly 5000 DPI, and I
would expect the reality to be quite a bit harsher than that.

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jabo
This article was on the home page for a while with the title "Immersion
scanning", a pretty dull one. Thanks to whoever changed it to "I just poured
water on my scanner"! Makes a much more intriguing and appropriate title.

~~~
JoeAltmaier
I disagree. It now sounds like 100 other clickbait titles - "The 10 best ways
to lose weight!", "The one true way to scan that the manufacturer doesn't want
you to know!"

~~~
mst
I assumed it was an intentional tip of the hat to the "I just put my laptop in
the oven" hack.

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rthomas6
I don't understand. Why not just use a decent resolution digital camera to
take a picture of the chips?

~~~
saganus
I don't see how that will help.

Wouldn't it be harder to try to get a good picture of the chip in such an
angle that you could read the etching?

I assume this angle will most likely be "from the top", such that it basically
turns into a scanner, and then it's easier to do it with an actual scanner.

~~~
rthomas6
But with the camera you have control over the lighting, and can move the
lighting such that the etching has more contrast.

I'll just assume that they tried the camera and the scanner works better.

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saganus
Besides being a very interesting hack, this made me laugh:

"(and contained as to not get IN the scanner, as that does NOT help the
process)"

Not sure why but this seemed really funny in the technical context.

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byuu
That's a really cool technique! Though it looks like his scanner glass is
scratched to hell and back (I wish they'd make the glass more scratch
resistant.) My exact scanner type, too. I would say it's definitely fast at
300dpi; but it takes well over 90 seconds for 600dpi (full scan, chip scan
would be faster of course), never dared try 1200dpi.

Also too bad I can't use use this trick when scanning cardboard boxes and
manuals.

~~~
Luc
> Though it looks like his scanner glass is scratched to hell and back

I don't think the scratches are on the scanner, since they're in the same
location on both images and the CPU had to be moved to be placed in water.

~~~
byuu
I tried to compare the two to rule that possibility out, but it's possible I'm
mistaken. That would be good though, I'd hate to think they were scanning
things with all that scratch damage getting on every picture.

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tambourine_man
I don't see resolution improving all that much, only contrast, as a quick and
dirty photoshopping can show:

[http://i.imgur.com/cGAPhgn.png](http://i.imgur.com/cGAPhgn.png)

~~~
falcolas
The contrast of the engravings on just the chip is what was improved the most,
not the resolution itself.

And speaking only for myself, there are still a number of markings in your
photoshopped image which I am unable to read, which can be clearly read on the
immersed image.

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Gracana
That's a solid improvement, but I bet they could get better results with some
other machine vision tricks. Diffuse on-axis lighting [1] would probably be a
good approach for this application; it's good at making subtle markings on
flat surfaces stand out.

[1] [http://www.microscan.com/en-us/products/NERLITE-Machine-
Visi...](http://www.microscan.com/en-us/products/NERLITE-Machine-Vision-
Lighting/Smart-Series-DOAL-Illuminators.aspx)

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puddlesmorning
Some holographers use Xylene as an index-matching fluid. Other suggestions
here including decalin and sugar water:

[https://books.google.com/books?id=tiGP9MrVs90C&pg=PA242&dq=i...](https://books.google.com/books?id=tiGP9MrVs90C&pg=PA242&dq=index+matching&hl=en&sa=X&ei=s4QZVZXZFIHTggSB24DYDQ&ved=0CCoQ6AEwAg)

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allworknoplay
I'd be curious whether you'd be able to reduce the noise (not the same as
lensing, obviously) if you used tape like this:
[https://www.youtube.com/watch?v=nRoL2q-tU-Q](https://www.youtube.com/watch?v=nRoL2q-tU-Q)

I've never had to scan things like your process so I have no clue; just a
thought.

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cordite
This sounds a lot like how an oil is used to look at slides in medical labs.

For example, it may be standard procedure to smear a sample along the slide,
place it on a stainer, retrieve it later, put some oil on it, and the lens of
the actual microscope will come in contact with the oil.

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userbinator
Fixing it on the top surface is good, but there's still another air-gap
between the bottom of the scanner glass and the head. A bit harder to fill
that gap with water though.

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jabo
Dont chips get destroyed when powerful light (like the one in the scanner)
hits them? Or is the point of scanning chips just to get their specs on file
and not to preserve them?

~~~
yannyu
There are some kinds of chips that can be reset by certain kinds of light
([http://en.wikipedia.org/wiki/EPROM](http://en.wikipedia.org/wiki/EPROM)).
Apart from that, packaged ICs aren't generally damaged by light that isn't at
a laser-like intensity.

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bradknowles
I wonder -- does scratch removal software help in such cases?

It seems to do wonders with certain cases of slide scans, so I wonder if it
helps with these kinds of wet-mount scans as well.

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aaronbrethorst
Wet mount scanning can do a world of good. Some examples:
[http://www.scanscience.com](http://www.scanscience.com)

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mrinal_pande
Pretty slick trick I must say...

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buraksarica
aaaaaand it's gone.

~~~
Tarang
It's just to get rid of the air gap between the glass and the chip. The intent
isn't to break the scanner.

