Audience Scanning in the U.S. ?

[gottaluvlasers]

This was presented by Pat Murphy and Greg Makhov. BRILLIANT paper.

I would highly reccomend this be read!!

-Marc

READ ME - READ ME!!!

[allthatwhichis]

Very nice, but the afterwork ADDish symptoms were kicking in and I had to save it. It makes me want to watch a beam show.

16

Photo taken at the Nov. 2007 ILDA Laser Theater, during the Lighting Dimensions International trade show in
Orlando. This was one of the first public demonstrations of CDRH-approved audience scanning using the Pangolin

Professional Audience Safety System.

I was there!

[dave]

I would say that applies to the rest of the world more than it does the states

[allthatwhichis]

I would say that applies to the rest of the world more than it does the states

I see it more as trying to get audience scanning legal in the US by setting standards. Since it is legal in other areas, this would be a good guide to follow to make the shows safer, but I feel it reads like a proposal to make it legal here.

[Banthai]

heres a comment from patrick

To ILDA Members and interested laserists:

As you may know, two important ILDA safety efforts have been in the area of laser pointers and aircraft, and in the area of audience scanning. Last week I was at the bi-annual International Laser Safety Conference, along with ILDA Safety Committee chair Greg Makhov. I presented a paper on laser/aviation safety, and presented a paper co-written with Greg on audience scanning.

This email message gives news about ILDA's proposal on audience scanning.

AUDIENCE SCANNING ANALYSIS AND PROPOSAL

In the audience scanning presentation, I pointed out that roughly 110 million people have been exposed to audience scanning with over the past 30 years. They have received over 11 billion pulses of laser light to their eyes -- most over the Maximum Permissible Exposure limit, and many (unfortunately) WAY over the MPE limit. Yet there have been "close to zero" reported injuries from shows using continuous-wave lasers over the past three decades. ("Injuries" are defined as any changes in vision which are noticeable or objectionable. Also, this does NOT include injuries from idiots using pulsed lasers, such as at the Aquamarine show in Russia last July, since audience scanning should NEVER be done with pulsed lasers.)

Clearly, audience scanning laser shows have a record of not causing injuries, despite often being far over the MPE.

In the presentation, I then went on to propose that laserists be morally and legally allowed to scan audiences with laser light that is 10 times the MPE, under certain conditions such as posting signs ("Caution: Extra-bright lasers in use. Do not look directly into beam.) In return, we believe that all audience scanning shows should be required to be measured, so the irradiance is known (and can be set safely). Fortunately, Greg Makhov has come up with a very simple way to measure a static beam and thereby know the scanning irradiance.

This proposal was well-received at ILSC. It is being given serious consideration by safety experts. It may be a long time before laws and safety standards such as IEC and ANSI agree to this proposal. But ILDA has let safety officials know that 1) audience scanning shows with CW lasers should not be feared and 2) audience scanning which is reasonably above the MPE (defined as up to 10 times the MPE) should be permitted under special conditions.

ILDA will continue working in this area. In the meantime, if you want the details of this analysis and proposal, there are two complementary sources. An updated version of the ILSC paper is at http://www.laserist.org/files/audience-scanning_overview_2pt1.pdf. In addition, the PowerPoint slides which I presented are at http://www.laserist.org/files/AudienceScanning_2009ILSCpresentation.ppt.

Hopefully these two sources will give you a good overview of our efforts. If you have additional questions about ILDA's activities in the area of audience scanning, please feel free to email or call me directly.

-- Patrick Murphy, ILDA Executive Director

all the best ..... karl

[mixedgas]

This is fine, if

I. The energy density gear is built into the projector and is calibrated.
II. It measures energy density, not just power
III It does it all show.
IV. You have a education campaign teaching people the need for the good gear, and to not accept the use of just any old lasers.

I am concerned about point one after working once again on a solid state system last night that was "all over the place" in power. I've seen it time and time and time agin, especially with blue dpss. The energy monitor must be in the projector, as well as a energy density meter in the OPs hand!


BTW, things like carefully set up ccd cameras can measure beam size, I have a Spiricon CCD system, works great, center the laser on the CCd, move the ccd back 10-100 cm, recenter the beam. Enter a power meter reading, then it does the math, you get density numbers, divergence numbers, and a beam profile on screen.

Problem is they are like 2000$ or so. A NIST tracable power meter is gonna be 1000$ more. How many people are willing to pay to play?

Steve

[White-Light]

Don't know if one of you ILDA members want to feed this back to ILDA, but whereas I think the proposals as a whole are great and just what the industry needs, I do think the known power vs distance requirements for home use projectors are way off.

Its all right a label saying safe at 30 metres and producing projectors on that basis, but how many people can honestly get their audience 30 metres away in a home environment or mobile disco?

It would be far more practicable for projectors for home / mobile use to have several power settings starting from 2 meters, 3 metres, 5 metres then 10 metres minimum rather than a setting guaranteeing safety at 30 metres simply because most home users / mobile disco users don't have 30 metres of building never mind safe zone!!

Two simple knobs on an out of the box solution would be best, one for distance which controlled power / lenses or both with simple pre-set stops eg 2,3,5 and 10 metres and another one for Level 1 / 2 control.

[mixedgas]

Two simple knobs on an out of the box solution would be best, one for distance which controlled power / lenses or both with simple pre-set stops eg 2,3,5 and 10 metres and another one for Level 1 / 2 control.[/QUOTE]


BRILLIANT IDEA!

Steve

[bridge]

thanks, Marc.
save it, .
Best regards!
Bridge

[aijii]

Excuse me if i've misunderstood... is that paper suggesting that all that is required to determine safe MPE is a static beam irradiance measurement ?