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(A) Implication, in my view:
A laser can shoot anything, from satellites to warships to tanks, not to
mention humans.
(B) One may challenge the efficiency of Laser as a weapon, because media (such as air or water) may dampen it (with different temperature, dust, rain, smoke, etc.)
(1) I am a biologist, not a physicist.
Please consult the section of Lasers as weapons" in
Laser
http://en.wikipedia.org/wiki/Laser
, particularly reference 33 there.
(2) (a) Theoretically the concerns are worthy.
Last night I recalled Dr. Charles K. Kao got Nobel Prize just a few months
ago, because, news media quoting Nebel committee, that he discovered
impurities in glass diminished the transmission.
Scientific Background on the Nobel Prize in Physics 2009: TWO REVOLUTIONARY
OPTICAL TECHNOLOGIES. Class for Physics of the Royal Swedish Academy of
Sciences, Oct. 6, 2009.
http://nobelprize.org/nobel_prizes/physics/laureates/2009/sciback_phy_09.pdf
Quote:
"An intense search for suitable transmission media in the optical domain
began at the beginning of the 1960s. The optical fiber was, however, mostly
set aside because of its high attenuation. * * * They [Kao and his sole co-
worker G.A. Hockman] investigated in detail the fundamental properties of
optical fibers with respect to optical communication. In particular, they
did not consider the physics
of waveguides only, as most of their research colleagues did, but also the
material properties. Their conclusions were presented by Kao in
London in the beginning of 1966 and published in June. The most important
result was that losses in dielectric media were mostly caused by absorption
and scattering. The predicted attenuation of a few dB/km was found to be
much less than that measured at the time. Consequently, the latter was
predominantly caused by impurities, in particular iron ions. Fibers with
glass of higher purity could be a good candidate for optical communication.
Damping caused by bending and waveguide imperfections, as well as
propagation and radiation losses were also analyzed and found to be small.
(b) And the concerns are valuable in real life.
Please consult section "2 Problems and considerations" in
Directed-energy weapon
http://en.wikipedia.org/wiki/Directed-energy_weapon
(c) However, Americans are ingenious. (Dr. Kao is a citizen of both United
States and United Kingdom, but never of People's Republic of China.)
(i) Here is the latest advance (besides the airborne laser shooting missiles
):
Press Release: Northrop Grumman Maritime Laser Clears Design Hurdles. Jan.
10, 2010.
http://www.irconnect.com/noc/press/pages/news_releases.html?d=183084
("operating in a marine environment and able to defeat small boat threats,
and ultimately could be applicable to other self-defense missions")
(ii) Reference 33 in (1) is:
Peter Pae, Northrop Advance Brings Era Of The Laser Gun Closer; Unlocking the
secret of creating the powerful beams with electricity will lead to smaller, portable
weapons, experts say. Los Angeles Times, Mar. 19, 2009.
http://articles.latimes.com/2009/mar/19/business/fi-laser19
(i) is about the successful field test in front of defense officials, after
Northrop received a grant from ONR in July, 2009.
【 在 choi 的大作中提到: 】
: VOA Chinese, Feb. 15, 2010.
: http://www1.voanews.com/chinese/news/US/LASER_MISSILE_20100215-84390572.html
: My comment:
: (a) 定向能 directed energy
: (b) It just came out that "Nathan Myhrvold, formerly Microsoft's chief
: (以下引言省略...)
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发表于 2-15-2010 12:23:26
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