New Scientist.

    http://www.newscientist.com/article.ns?id=3Ddn8060

Electrically alterable lense sounds the most interesting. Physical=20
shape is not altered. rather internal liquid crystal material changes=20
refractive index with applied voltage.


        RM

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mic is clamped to a back tooth. This, they say, shields it from=20
external vibration while still picking up speech from ...  a vibration=20
sensor is set in resin and moulded to fit like a dental cap or plate.=20
A low-power radio link transmits audio to a higher-power transmitter=20
built into ear-muff headphones, so wearers hear their own voice as it=20
is sent to others. A push-to-talk function is provided by a=20
tongue-operated switch. ... works in noise up to 160 decibels, which=20
is louder than a jet aeroplane taking off. They also note that the mic=20
works inside gas masks and that encryption can be added for security.=20
The mic can be removed for cleaning to avoid infection.

_____

The traditional way to launch an airship is to tether it horizontally=20
and then cast off from both ends, so the craft lifts gracefully. But=20
it needs a lot of room. So Boeing fills the ship with helium while the=20
rear is tethered with a short fixed line and the front with a much=20
longer line that pays out as more gas is pumped into the front end.=20
The nose rises in the air, until the craft is standing nearly=20
vertical. Both lines are then cast off at the same time and the=20
airship shoots up like a rocket, at around 5 metres a second. As the=20
ship rises, a valve at the rear vents air, and the helium at the top=20
expands - due to the lower atmospheric pressure at altitude - to fill=20
the entire ship. This brings the blimp horizontal, enabling it to=20
hover.

______________

... University of Central Florida in Orlando is claiming a way to make=20
electric lenses of any size =96 and cheaply too.
First, the curved surface of a fixed-focus lens is coated with=20
transparent indium-tin-oxide to make a concave or convex electrode.=20
The flat surface of a plain, transparent plate is similarly coated.=20
The space between the two plates is then filled with nematic liquid=20
crystal material.
When a voltage is applied across the sandwich, the curved shape of the=20
lens electrode creates an electric field that varies in strength from=20
centre to edge. This creates a matching gradient of refractive index=20
in the liquid crystal. Changing the voltage changes the gradient, and=20
thus the focal length of the sandwich lens.
The basic design can be scaled to any size, says the patent. The cost=20
could be further reduced by making both electrodes flat plates and=20
putting ridges on one to make it New Scientista Fresnel lens. Finally,=20
If one electrode is reflective, it makes an electrically focused=20
mirror.
Get the pdf file which tells how they make smart lenses in Orlando=20
here

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Ref: MM


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