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Comment Re:I'm sick of this (Score 1) 114

> Learn to read... as this clearly stated that that sentence was referring to a common complaint by pilots, not the particular article.
Do it yourself - the comment I answered to was only about eye damage and the title of the referenced article is "Pilot Has Eye Injury From Green Laser".

> MPE is for visible region is 1 mW / cm^2, which can be reached with single digit watts into a meter diameter beam, assuming the beam is evenly distributed and has no potentially reflecting surfaces involved.
Wow, now it is "single digit" watts, there is certainly a progress over "a couple of watts". But no, it cannot be reached, it would be 0.7 mW / cm^2 from a 9W laser in the specified conditions. Just learn basic math as I told you :D.

Comment Re:I'm sick of this (Score 1) 114

> lighting up a windshield with 100+ lux will kill visibility at least which is the main complaint from pilots trying to land
No, the main complaint in the discussed article was eye injury (that cannot happen), not losing visibility for a minute.

> A couple watts at a spot size of ~ 1-2 m can reach the damage threshold in the visible range
No, they cannot. The limit for a fully dilated pupil is 9 mm which means 2000 mW / (1000 / 9) / (1000 / 9) = 0.162 mW of laser power enter the eye for a very short moment. Class II is 1 mW so even taking into account beam imperfections such a blast is significantly weaker. Learn basic math please.

Comment Re:I'm sick of this (Score 1) 114

What?! 5000 feet?! This story is utter BS. Let's take, for example, specifications for Wicked Lasers Krypton ("The Krypton is the world's most powerful green handheld laser", priced $999). "Beam Distance 0.25 Lux - 47475 meters". Let's assume that the beam was from the ground at about 45 degrees. This gives the distance of about 7000 feet. (47475 / (0.3048 * 7000)) * (47475 / (0.3048 * 7000)) * 0.25 - this gives about 120 lux. To put this into perspective, direct sunlight is more than 32000 lux. Yes, laser is a point source and Sun is not exactly but that should not matter with such a difference.

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