On Friday 06 December 2013 15:04:27 Bertho Stultiens did opine: > On 12/06/2013 08:24 PM, Gene Heskett wrote: > > Hence the cataract warnings that seem to surround the long IR CO2 > > models. Unforch I do have some already. > > Cataract inducing lasers are at ~1500nm (often Yag type lasers). The > 1.5um is small enough to pass through the cornea and will induce > coagulation in the lens (making it milky-white). Your cornea also will > take damage, but the bulk energy at these wavelengths (1..2um) are > absorbed by the lens. > > Longer wavelengths are readily absorbed by water and will cause the > tearfilm to boil off. If any appreciable amount of energy still passes > onto the anterior chamber (between lens and cornea) then the water there > will heat. Too long exposure will cause the lens to coagulate (at about > 55..60 degrees C) and therefore also induce a cataract. > > > When you get into such situation, you'd be swearing and grumbling that > you /should/ have been wearing eye protection. ;-) > > Do not mess with your eyes. > > > (full disclosure: I workes at a hospital's department of ophthalmology > for 10 years).
Sounds like someone who has walked that walk, RANT MODE ON and a subject that brings up a sore point with me in that 55 years ago I could actually find an ND9 panel for my arc shield/helmet, making it usable but even then I preferred the smith wrench because of ones ability to modify the carbon content of the weld and see both the surroundings and the weld puddle thru a set of ND5's. Today its ND10's only, which are so damned dense you can't see where to strike the arc even with bright sunlight on the workpieces. And getting these high priced automatics set to work well is a dream I haven't managed to do well yet. Mostly all you can see is the arc itself but dammit all to hell, one needs to be able to see the work surface for at least a cm around the arc in order to really be able to drive the j-stroke cleanly down the joint AND get good penetration. I can manage to run my mig when I have to, but if I could actually see what the hell I was doing, I could do a hell of a lot better than I can do when blinded by excess ND. /RANT MODE. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> You will pay for your sins. If you have already paid, please disregard this message. A pen in the hand of this president is far more dangerous than 200 million guns in the hands of law-abiding citizens. ------------------------------------------------------------------------------ Sponsored by Intel(R) XDK Develop, test and display web and hybrid apps with a single code base. Download it for free now! http://pubads.g.doubleclick.net/gampad/clk?id=111408631&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
