My first eye injury with a DPSS laser
(and, I hope, the last)



(Date of injury: June, 16th 2005, evening.)

Just thinking about what experiment I can do next with my green DPSS. Nothing on my mind... just sitting in a chair and lighting up my room with the laser. Because the power is 15 mW, there’s no need to smoke or make fog to see the beam: the dust particles in air are enough. The beam is much more visible when I’m looking toward the laser than it is when the laser is pointed away from me.

I have an idea to reflect the beam from window glass. If each surface has only about 4% reflectance, both window glass surfaces should have about 8% reflectance. I point the laser toward the window and look the reflected beam from window. Reflected beam looks stronger than beam pointed toward the window.

My next, and very stupid wonder is “what will it be like if reflected beam hits my eye?” (8% of 15 mW is about 1.2 mW, so maybe that’s equivalent to laser class IIIa, and if the beam passes across the eye for part of second, nothing will happen...).

But, I was blinded, for tens of minutes, and had lack of sensitivity to green (because my retina is oversaturated with the green color). The laser spot on the wall appeared white. After some time (I’m not really sure how long), my sensitivity to green came back, and my vision was “like new”.



Now, the worst part of this evening...

The next incredibly stupid thing I did was to try to “scan” the beam very fast, directly across my left eye. My thought is “very fast scan will not damage my eye?” And I was very curious what would happen. My very first observation surprised me - I scanned very fast, but I was expecting white blinding light in the middle of my vision, like what I got from the window glass. But, in the middle it was black!!! I was very surprised, and my curiosity become stronger: “let’s try again, to confirm what I saw” ...“Yes, it is black in the middle!” (My second attempt of “scanning” is not so fast like first time.)

But, then, something was strange when I looked at the laser spot on the wall with my left eye - there wasn’t any spot at all, just green light around center of my vision, and in the middle ...nothing, or maybe only a fuzzy grey “cloud”!

OH NO!!! PANIC!!! WHAT NOW?!?! “Maybe after half an hour spot will disappear?” ...No! “I will go to bed, and maybe tomorrow the spot will have disappeared?” ...No! In the morning I tried to read a document on the computer monitor, and it looked very annoying — stereoscopic vision was not working right in the middle of my visual field. Letters were “blinking” when I tried to read text. My brain tried to correct this “malfunction”, but all that happened was that I got a strong headache.

I used the Google search engine try to find something about eye injury, and found “calming” document at: http://chppm-www.apgea.army.mil/rfup/website/FIG17.HTM

So, I hope after six months I may recover my vision. The next day I went to see an opthamology doctor. He is not so sure that I will ever again see with my left eye like before. He prescribed some vitamins for me: “Makulin” which has Lutein and vitamin E in capsules; and Vitamins for eyes (“Eye-vites”) which contain Beta carotene, vitamins E and C, Zinc, Copper, and Selenium. I need to take this vitamins for a few months.



There is how it looks like:
(Note: the pictures are captured by digital camera, and corrected in Photoshop to show you what I actually see.)
(I can’t find a video output from my eye-cameras :o)

(Almost) Non destructive injury: 
  
Destructive (permanent) injury: 
 
  
 
This is view of the spot on the wall, very similar to what it looks like the beam hits your eye. If you see something like this, STOP IMMEDIATELY, but do not panic. Your vision will recover sooner or later. However, looking into any laser beam with more power than a few microwatts of power at all is not recommended!!! It may damage your vision only a little if you do it once, but cumulative and prolonged exposure can cause serious and permanent damage to your eyes.

 		   If you see something like this, DO PANIC — now it is TOO LATE!!! Immediately go to see opthamologist and ask for help! If nothing else, the doctor will examine your eyes and determine how much damage has occurred. However, it is much better to avoid staring into a laser beam. It is not worth losing your vision just to satisfy your curiosity! (Black spot = burned retina!)

 
 
  
 
For a while, your vision will be discolored at the area where the most intense laser beam hit your eye (only for green color if laser was green).


 		   This picture shows about how I now see when I’m reading some text. If I’m just looking at a white, gray, or black background, I don’t see anything unusual — no white, gray or black spot. But when I look at something, the colors around the “dead” vision area make the spot appear colored, and mixed with the surrounding colors (black text on white paper = grey spot).

 
 
  
 
Another example of discolored vision. The spot on the left is how looks a weak laser spot appears before blinding, and on the right is how it looks after non-destructive power for a while. (This is for a green laser. With a red laser; your vision will be discolored for red.)
 		   This is another example of mixing of surrounding colors (green + black = greenish/grey spot). Now, you can imagine how annoying is all the time watching “wrong” color information after a laser injury. For God's sake, DO NOT DO THIS TO YOURSELF!
 




Conclusion: Experimenting with lasers makes me excited, happy and satisfied. But sometimes, in part of second this hobby can make an invalid of me. There are not only dangerous with strong laser light, but also possible injury by high voltage, and some “wild” (mostly rotational) tools. BE CAREFUL!!! Don’t follow my stupid curiosity!!!
 


Date: June, 23rd, 2005.