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Comment Re:Gross, but... (Score 1) 618

If a Pharma company invented any of them today there is no way they'd even be allowed for use with a prescription, let alone stocked in 500-count bottles

Here in Netherlands, they are not allowed to be sold in greater quantities than 20 pills, just to reduce the perception that they are harmless. The strange thing with paracetamol toxicity is that it would be trivial to add a harmless antidote against overdosing to the pills, but this isn't done despite the fact that paracetamol poisoning is the most common type overdose of pharmaceutical products.

Comment Re:Infared Contact Lenses? (Score 1) 320

Another poster posted a link to a youtube clip of these contact lenses. They come with built-in fake irises, so only the pupil appears dark. Regarding the definition of near infrared: the standard range of visible light is assumed to be up to 740 nm, but I have worked with 800 nm near-IR lasers for many years and they are still visible, although a 1 watt beam appears to be comparable to that of a 1 mW laser pointer at 675 nm. See for yourself here for the sensitivity curve: (under fundamental spectra or luminous efficiency).

Comment Re:Gross, but... (Score 1) 618

You seem to be stating that if I accidentally took 3 paracetamol pills,

See . Short version: maximum recommended intake is 3 grams per 24 hours; a single dose of 10 g can be fatal, as are a few days in a row at 10 g per day spread out over multiple smaller doses.

Comment Re:Infared Contact Lenses? (Score 1) 320

if you put one layer on top of the other, even transparently, I am not sure.

Ink on paper works like this: the paper acts as a diffuse reflector; the ink absorbs light for certain wavelengths, but the light that is not absorbed passes through without changing direction. Putting two layers of ink with different absorption wavelengths on top of each other will result in only the wavelengths that are *not* absorbed by either being reflected by the paper. This is the whole point of the CMY(K) printing process.

Maybe you are thinking of paint, which typically includes its own reflective particles. But paint needs to be applied in a much thicker layer (0.1 mm or 4/1000 inch) to do its job, so it would be rather noticeable; the deck of cards would be 5 mm (1/4 inch) thicker and you would be able to feel the paint with your fingertips.

Comment Re:a few laws of physics problems here (Score 1) 90

But if you collecting acoustic data over a period of time, transient sounds (noise) average out, and the loud peak (gunshot)

Well yeah, if you want to pinpoint the source of a massive transient or the source of an annoying continuous whistling sound or a never-ending repeated playback of some secret message, this sensor could work. But it would not be very useful for recording private conversations.

But look at it from this side: a normal microphone measures pressure as a function of time, i.e. p(t). If their is only one source of sound, you can reconstruct the sound wave at the source. If there are two sources, it becomes impossible to distinguish. This transducer will generate three signals: vx(t), vy(t), and vz(t). If you have three sources of sound, then you could, with proper tuning and calibration, disentangle the signal and reconstruct the output of each of the sources individually. As soon as there are more than three sources, say in a pub with 20 conversations going on at the same time, you cannot do this anymore simply because there are more bits of data being transmitted than being transduced; you would need to solve a system of three equations with twenty unknowns.

Comment Re:Infared Contact Lenses? (Score 1) 320

... a well chosen filter can indeed make two light bundles look different that look exactly the same without the filter.

Yes, that's what makes the skin look weird under cheap white LED lights and older fluorescent tubes. This effect is called metamerism.

But unless you print the entire back sides of the playing cards with a pattern of two different inks that look the same under the casino lights but look different through your filter, you cannot use this to label cards after the fact. Ink absorbs light, so when applied to white paper, the surface will look darker than before, no matter what.

Comment Re:Infared Contact Lenses? (Score 1) 320

...IR detector card has a strip of chemicals on it that glow pink when a remote control is aimed at it.

That is not frequency doubling, but a special form of phosphorence. Visible/blue light is used to generate long-lived excitations in the molecules. Infrared then excites them further to a slightly higher level with a short excitation lifetime; as that excitation decays, it emits visible light. It shares the disadvantages of common phosphorence: it is not directional.

Comment Re:Infared Contact Lenses? (Score 4, Informative) 320

Near-infrared ink (as posted by an AC) sounds like the most plausible approach. In the range 700-750 nm, the sensitivity for light is less than 1% of the peak sensitivity. You would need (1) a proper long-wavelength-pass filter, (2) ink that absorbs only in this wavelength range, and (3) an illumination source that is heavy in this wavelength area (e.g. halogen/incandescent lights).

For the naked eye, the ink would appear as a very pale cyan color. With a proper filter, everything would look very dark due to the filter removing 99% of the visible light, but the ink would show up with much more contrast. Effective long-pass filters do exist, e.g. Schott RG695 or RG715 for a 695 or 715 nm cut-off, respectively. There are plenty of suitable dyes. Probably you would want to have this filter only on one eye, otherwise the world around you might appear very dark.

The other theories that have been posted here make no sense.

Frequency-doubling needs extremely high intensities (like a high-power or focused low-power laser beam), which would render you blind. Moreeover, frequency-doubling requires proper phase matching, which boils down to the requirement of an exact combination of angle and wavelength.

Polarizers: it is not possible to turn unpolarized light into polarized light without throwing away half of the light. Once the light is polarized, the polarization direction can be manipulated with optically active materials, though.

A high-refractive index coating would not only change at the Brewster angle, it would make the cards much more glossy as seen from any angle. It is not possible to make the refractive index change dramatically within a short wavelength range without changing the absorption as well, so the glossiness would appear in visible light as well.

A phosphor coating would not work for several reasons: phosphors do not emit the phosphorence in the same direction as the absorbed radiation; they always convert from short wavelengths to long wavelengths, and the phosphorence light would be completely out of focus.

Comment Free electron lasers as EUV source (Score 1) 32

Average power is low now, but there is a clear path to at least kilowatt average powers (see the LBNL NGLS) and 10s of KW are pretty straightforward.

A clear path to kilowatt powers, that's sounds a bit like the stories about the EUV sources years ago. Reality turned out to be quite a bit harder...

There has been quite a bit of work on EUV / Xray optics, but again the parts are really expensive (an X-ray mirror runs $1M. )

Are those normal incidence or grazing incidence mirrors? For proper imaging, you need to image one area onto another area with low aberrations, not one focal point onto another focal point. This is far easier to do with mirrors designed for normal incidence than for grazing incidence. Even then, it turns out that you need about 10 reflections from the EUV source to the silicon wafers; it's because with every reflection you lose about 1/3 of the power that we would like to have a kilowatt to start with. If the reflection losses are a bit larger due to a larger number of mirrors or a higher per-mirror loss, then you need to start with even more power.

Comment Re:ASML (Score 4, Interesting) 32

ASML aren't a "light source maker", they don't "make" anything actually.

With the acquisition of Cymer, ASML is actually a light source maker.

integrate stuff from different suppliers, and have contractors bolt it together.

It is true that ASML outsources the manufacturing of most components as far as it involves materials processing (machining, coating, soldering) and off-the-shelf components (pumps, filters, sensors, computers, bolts, cables, etc.). But the actual assembly and tuning of these thousands of components is done by ASML's own employees in ASML's own cleanrooms. As I am typing this, this is happening about 15 meters below my office.

Given the wide variety in technologies used in these scanners, and given how fast the technology changes, it wouldn't make much sense to do all the materials processing in-house. For me as a design engineer it is quite cool that I generally only need to worry whether the design of a component is manufacturable by some supplier in the world, rather than that I have to keep in mind what our own tools, which have to be used because they are not yet written off. That would slow down development tremendously -- it is already hard enough to keep up with Moore's law without such a restriction.

(The above are my own views/opinions yadda yadda)

Comment Re:EUV source (Score 4, Informative) 32

"a bunch of 193nm immersion tools (for triple patterning) the EUV may never make economic sense for fabs."

A problem with dual/triple patterning is that it is mostly suitable for making parallel lines, not complex patterns. It happens that this works very well for NAND memory, but for CPUs, not so much.

Another problem is that you need 2x or 3x the number of process steps, which puts the higher price for EUV machines into perspective.

I expect that the primary target at the moment is to develop the technology. Once we're there, more attention can go to reducing costs.

Disclosure: I work at ASML on the EUV source. But this are my own views; I don't officially represent the company.

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