Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!burl!ulysses!bellcore!decvax!ittatc!dcdwest!sdcsvax!sdcrdcf!hplabs!qantel!lll-lcc!lll-crg!seismo!rochester!ur-tut!aptr From: aptr@ur-tut.UUCP (The Wumpus) Newsgroups: net.auto Subject: Re: Defeating Laser Pulse Speed Enforcing Message-ID: <86@ur-tut.UUCP> Date: Sat, 22-Mar-86 13:22:07 EST Article-I.D.: ur-tut.86 Posted: Sat Mar 22 13:22:07 1986 Date-Received: Wed, 26-Mar-86 02:24:33 EST References: <371@ihlpf.UUCP> <185@chronon.UUCP> Organization: Univ. of Rochester Computing Center Lines: 28 > >I wonder how hard it would be to turn a car "black" well into the > >infrared range? > > > > I don't think I'd like my car to be completely "black" at IR during > the summer! Prolly not even during the winter. It's hot enough reflecting > all the heat it does now... Rather than absorb the IR laser, I'd rather > jam it by sending my own noise (lots of random heat). > To make the car "black" to IR in the true sense would mean the absorbtion of IR waves, but there are other ways to make the car appear to be black to IR. The physical effect known as Thin-Film-Interference allows things to appear to be black while not actually being so. Have you ever noticed a pool of water with a slight bit of oil in it deffracts light? Well that is one example of thin film interference. What is happening in thin film interference is that the light is reflected both by the top and bottom surfaces of the film in such a manner that the light reflected from the top and bottom are 180 degrees out of phase with each other, and therefore cancel each other. The only real problem with using this to block out IR is that you are talking about put a coat of paint on that must be correct to under 10e-10 m, but with todays technology it isn't to hard. Oh yes, I also believe that it would mean that you would never be able to wax your car again because of the changes the wax would cause. The Wumpus UUCP: allegra!rochester!ur-tut!aptr BITNET: aptrccss@uorvm