Wide Scan Angle lens

[gottaluvlasers]

ANDYF-

i own a 5W yag for professional shows. i am by no means a superstar laser company. nor have i ever claimed to be. i do good for what i have and i think im making a pretty good name for myself in my field. i am, in my opinion, prob one of the youngest companies (only about a yr and a half-2 years) with the most to learn companies in the USA trying to learn as much as i can from alot of the guys here.

HOWEVER-

i definitely know enough about the technology and theories and safety involved in lasers to know that the video i saw doesnt even REMOTELY come close to what you tried to provide as an explanation.
i do not want to get into a pissing match with you. like i said from the begining, i am sure youre are a great guy and have a great and prosperous company in Romania. but to sit there and try to justify that video with some excuse about low powers, and fancy camera lenses, and trick photography or whatever just insults my intellegence and probably everyone else on here who watched that video!

"people arent covering their faces and dropping to the floor..." OF COURSE NOT!!!! THEY dont know what they're being blasted with!!! YOU'RE the professional!!! NOT them!!!

[godfrey]

Marc. I believe this is what you and I were just talking about an hour ago.

I am adding this for everyone to read - I think this was discussed on a previous thread, but briefly back in 2007.

It CAN NOT be stressed enough - it's not that long.




Taken from: http://publicsafety.tufts.edu/ehs/do...rogram2005.doc



APPENDIX A
(From Laser Focus, August 1977)


Accident Victim's View

Because laser injuries to eyes are rare, workers tend to discount the importance of safety precautions. The following dramatic account by Dr. C. David Becker, a victim of such an accident earlier this year, was prepared in the hope that his experience may increase vigilance among his colleagues.

The necessity for safety precautions with high power lasers was forcibly brought home to me last January when I was partially blinded by a reflection from a relatively weak neodymium-YAG laser beam. Retinal damage resulted from a 6 millijoule, 10 nanosecond pulse of invisible 1064 nanometer radiation. I was not wearing protective goggles at the time, although they were available in the laboratory. As any experienced laser researcher knows, goggles not only cause tunnel vision and become fogged, they become very uncomfortable after several hours in the laboratory.

When the beam struck my eye I heard a distinct popping sound, caused by a laser-induced explosion at the back of my eyeball. My vision was obscured almost immediately by streams of blood floating in the vitreous humor, and by what appeared to be particulate matter suspended in the vitreous humor. It was like viewing the world through a round fishbowl full of glycerol into which a quart of blood and a handful of black pepper have been partially mixed. There was local pain within a few minutes of the accident, but it did not become excruciating. The most immediate response after such an accident is horror. As a Vietnam War Veteran, I have seen several terrible scenes of human carnage, but none affected me more than viewing the world through my bloodfilled eyeball. In the aftermath of the accident I went into shock, as is typical in personal injury accidents.

As it turns out, my injury was severe but not nearly as bad as it might have been. I was not looking directly at the prism from which the beam had been reflected, so the retinal damage is not in the fovea. The beam struck my retina between the fovea and optic nerve, missing the optic nerve by about three millimeters. Had the focused beam struck the fovea, I would have sustained a blind spot in the center of my field of vision. Had it struck the optic nerve, I probably would have lost the sight of that eye.

The beam did strike so close to the optic nerve, however, that it severed nerve-fiber bundles radiating from the optic nerve. This has resulted in a crescent-shaped blind spot many times the size of the lesion. The diagram is a Goldman-Fields scan of the damaged eye, indicating the sightless portions of my field of view four months after the accident. The small blind spot at the top exists for no discernable reason; the lateral blind spot is the optic nerve blind spot. The effect of the large blind area is much like having a finger placed over one's field of vision. Also I still have numerous floating objects in the field of view of my damaged eye, although the blood streamers have disappeared. These "floaters" are more a daily hinderance than the blind areas, because the brain tries to integrate out the blind area when the when the undamaged eye is open. There is also recurrent pain in the eye, especially when I have been reading too long or when I get tired.

The moral of all this is to be careful and to wear protective goggles when using high power lasers. The temporary discomfort is far less than the permanent discomfort of eye damage. The type of reflected beam which injured me also is produced by the polarizers in q switches, by intracavity diffraction gratings, and by all beamsplitters or polarizers in optical chains.

[andyf97]

Ok so, you say we are not professional with your 2 ... years experince. I have 15+ years experience, over 20 events per month excluding busy periods of the year and no accidents. I think that kind of endorces that we are working in a professional mannor isnt it?.

I find these 130mW laser pointers modified from DVD players more of a worthwile topic of safety. I do not see you posting messages about those pointers used by people with 1 week of experience as its those who damage this industry not us.

So I wont comment further on this topic, It is starting to get too personal, legaly slanerious and insulting.

ANDYF-

i own a 5W yag for professional shows. i am by no means a superstar laser company. nor have i ever claimed to be. i do good for what i have and i think im making a pretty good name for myself in my field. i am, in my opinion, prob one of the youngest companies (only about a yr and a half-2 years) with the most to learn companies in the USA trying to learn as much as i can from alot of the guys here.

HOWEVER-

i definitely know enough about the technology and theories and safety involved in lasers to know that the video i saw doesnt even REMOTELY come close to what you tried to provide as an explanation.
i do not want to get into a pissing match with you. like i said from the begining, i am sure youre are a great guy and have a great and prosperous company in Romania. but to sit there and try to justify that video with some excuse about low powers, and fancy camera lenses, and trick photography or whatever just insults my intellegence and probably everyone else on here who watched that video!

"people arent covering their faces and dropping to the floor..." OF COURSE NOT!!!! THEY dont know what they're being blasted with!!! YOU'RE the professional!!! NOT them!!!

[Dmxlaser]

Ok so, you say we are not professional....
<snip>

To Gottaluvlasers:

I haven't responded to this thread before, but I must say that andy knows a lot more then you may think he does.

Ever checked out this video: http://www.youtube.com/watch?v=mPnCjMszSq4 Here he does a full color show in broad daylight....ever tried that ? It's a heck of a job, still the beams fly OVER the people, not INTO them.

As for other video's, everybody can mae a video where a laser looks brighter then it is, just add the proper amount of smoke at the right location and you can make a 100 mW look like a 10 Watt.

Lasers and lasershows take more then rules, they need to be quality, they need to be creative and they need to be worthwhile to the customer.

the fact that in the US you cannot do European-Type shows is a thing that I feel frustrates you and you take this out on European companies that do these shows. Just to feel good about yourself you tell them they should not do the show this way.

What experience do you bring in that area ? have you ever done a show in Europe ?

Just think before you do and....a 5 watt is probably more power then you'll ever need.

Just for your knowledge...my company did a Live show at a Ferry Corsten concert with "just" 5 lasers and only 1 of these was a 5 watt...in a hall the size of a stadium...

So you see....it's doesn't need to be high power to be good.
Same goes that what you see doesn't have to be as high powered as you think it is.

Cheers and take care out there...

Peter

[JStewart]

Marc, I tend to agree about how the footage looks. It has to be up there in the top ten most potentially dangerous looking shows I’ve seen. (I must use this on my next laser safety training course).

Of course, it is always difficult to make an accurate assessment from video footage which can distort a number of factors. But I would say it is very likely that the static finger beam effects will be over the applicable MPE. But who knows, Andy may have done the maths, checked the measurements and know the irradiance and exposure durations etc.

Best regards

James Stewart

[aijii]

You cannot calculate the MPE off a photo or video footage, so i do not think it is entirely fair that you judge andy's ability to perform a show safely based on some footage.

Unless you were also at the show, of course.

[andyf97]

Oh shut up guessing,

Nobody yet asked what the power of those lasers used are.

They were 50watt yags with 0.4mrad, its ok?

You cannot calculate the MPE off a photo or video footage, so i do not think it is entirely fair that you judge andy's ability to perform a show safely based on some footage.

Unless you were also at the show, of course.

[soforene]

Sorry lads.
I know bugger all about Lasers but throwing a 50 watt laser into the eyeballs of someone withiin 100 feet must (even to my uneducated mind) qualify as retarded.

Unless of course Andy missed a smiley off his post thereby totally missing the whole "ironic" angle.

[godfrey]

I find these 130mW laser pointers modified from DVD players more of a worthwhile topic of safety. I do not see you posting messages about those pointers used by people with 1 week of experience as its those who damage this industry not us.

Believe me Andy, you don't want to get him started on that topic - me either. Personally, I was just thrown off "the other laser forum" because of my belief towards the irresponsible marketing practices of that "other laser company". And I'm glad they did it. Now I can continue my work here at this forum as a professional.

Laser pointers, high powered ones, should not be in the hands of kids. I totally agree with you (and Marc would as well) that it has had an impact on our profession.



Lets not get everyone in a pissing match over this... We're all adults - not 16 year old kids with a 500mW battery powered laser pointer.


Phil

[gottaluvlasers]

to all-

my apologies for turning this thread negative and "hijacking" it. that was NOT my intention.

i will start a new appropriate thread and finish commenting.

-Marc