From: eccliesiastes2010@yahoo.com (eccliesiastes-JamesRose) Newsgroups: alt.mindcontrol Subject: Hypersonic Sound, &, The Effect of Radiation On Matter Date: 20 Sep 2002 02:13:36 -0700 Organization: http://groups.google.com/ Lines: 98 Message-ID: <10ac1ac7.0209200113.6ad046ea@posting.google.com> NNTP-Posting-Host: 63.225.199.136 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: posting.google.com 1032513216 11318 127.0.0.1 (20 Sep 2002 09:13:36 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: 20 Sep 2002 09:13:36 GMT Path: rsl2.rslnet.net!cyclone.bc.net!newsfeed.stanford.edu!postnews1.google.com!not-for-mail Xref: rsl2.rslnet.net alt.mindcontrol:3025 Popular Science We've heard hypersonic sound. It could change everything. by Suzanne Kantra Kirschner It's the most promising audio advance in years, and it's coming this fall: Hypersonic speakers, from American Technology (headed by the irrepressible Woody Norris, whose radical personal flying machine appeared on our August cover), focus sound in a tight beam, much like a laser focuses light. The technology was first demonstrated to Popular Science five years ago ("Best of What's New," Dec. '97), but high levels of distortion and low volume kept it in R&D labs. When it rolls out in Coke machines and other products over the next few months, audio quality will rival that of compact discs. The applications are many, from targeted advertising to virtual rear-channel speakers. The key is frequency: The ultrasonic speakers create sound at more than 20,000 cycles per second, a rate high enough to keep in a focused beam and beyond the range of human hearing. As the waves disperse, properties of the air cause them to break into three additional frequencies, one of which you can hear. This sonic frequency gets trapped within the other three, so it stays within the ultrasonic cone to create directional audio. Step into the beam and you hear the sound as if it were being generated inside your head. Reflect it off a surface and it sounds like it originated there. At 30,000 cycles, the sound can travel 150 yards without any distortion or loss of volume. Here's a look at a few of the first applications. 1. Virtual Home Theater How about 3.1-speaker Dolby Digital sound? With hypersonic, you can eliminate the rear speakers in a 5.1 setup. Instead, you create virtual speakers on the back wall. 2. Targeted Advertising "Get $1 off your next purchase of Wheaties," you might hear at the supermarket. Take a step to the right, and a different voice hawks Crunch Berries. 3. Sound Bullets Jack the sound level up to 145 decibels, or 50 times the human threshold of pain, and an offshoot of hypersonic sound technology becomes a nonlethal weapon. 4. Moving Movie voices For heightened realism, an array of directional speakers could follow actors as they walk across the silver screen, the sound shifting subtly as they turn their heads. 5. Pointed Messages "You're out too far," a lifeguard could yell into his hypersonic megaphone, disturbing none of the bathing beauties nearby. 6. Discreet Speakerphone With its adjustable reach, a hypersonic speakerphone wouldn't disturb your cube neighbors. ---- Effect of Radiation On Matter You may click on any of the types of radiation for more detail about its particular type of interaction with matter. The different parts of the electromagnetic spectrum have very different effects upon interaction with matter. Starting with low frequency radio waves, the human body is quite transparent. (You can listen to your portable radio inside your home since the waves pass freely through the walls of your house and even through the person beside you!) As you move upward through microwaves and infrared to visible light, you absorb more and more strongly. In the lower ultraviolet range, all the uv from the sun is absorbed in a thin outer layer of your skin. As you move further up into the x-ray region of the spectrum, you become transparent again, because most of the mechanisms for absorption are gone. You then absorb only a small fraction of the radiation, but that absorption involves the more violent ionization events. Each portion of the electromagnetic spectrum has quantum energies appropriate for the excitation of certain types of physical processes. The energy levels for all physical processes at the atomic and molecular levels are quantized, and if there are no available quantized energy levels with spacings which match the quantum energy of the incident radiation, then the material will be transparent to that radiation, and it will pass through. Electromagnetic spectrum annotated with physiological effects> Index http://hyperphysics.phy-astr.gsu.edu/hbase/mod3.html#c1 James