5mW 650nm Laser with Powell Lens

[aljamesg]

I've been working on a device that utilizes a 5mW (as advertised) 650nm laser paired with a Powell lens for a line laser function. After checking out laser safety info on this forum, I wanted to confirm the actual output of the laser, so I got myself a UT385 Laser power meter from Uni-t. It just arrived today, and I ran a test on the laser after fixing a dot focusing lens to cover the entire beam on the sensor. Turns out, the power measures just under 6mW. Would this put it in the 3B laser classification?

The device doesn't have any way for the laser to reflect directly back into the eye. However, there's visible scattered light from a height gauge. When I measure the light's cross-section through the Powell lens, it shows around 0.2mW. I'm hoping to hear from experienced individuals here for any insights. Any feedback you can provide would be greatly appreciated.

 

[paul1598419]

The cylindrical lenses that give a line output is quite different from a collimating lens. Any lens that would collimate the light would make your laser greater than 5 mW. But, the line is a totally different animal in that your beam is spread out and is therefore actually less than 5 mW. Any specular reflection would only put a small portion of the beam into your eye. The further away and the longer the line, the less power that can be delivered into your pupil. Hope this helps you.

 

[aljamesg]

Thank you for the reply! If a Class 3R laser is rated between 1 to 4.99mW and measures around 6mW when using a collimating lens, does this automatically classify it as a Class 3B laser? Despite this, my device won't use a collimating lens but instead, a cylindrical lens.

Regarding laser classification as a "pointer," my device utilizes a laser for measurement indication, not for pointing, and it's self-contained. What factors determine a laser being categorized as a "pointer"?

 

[atomd]

"Classes" laser power is defined over certain aperture. Maybe it's enough for you to enclose the beam in device for long enough that it spreads to 6/5 of aperture

 

[Encap]

It doe not matter what any seller. reseller. or marketer marketing a laser diode "as advertised" says.
Output over 5mW is over 5 mW. FDA laws, rules, and regulations are what they are. What a seller says does not constitute "classified"as. There are hundreds of sellers marketing laser devices with bogus output specifications to circumvent the FDA laser device requirements.
If whatever you are working on for whatever reasons needs to comply with FDA laws, rules, and regulations then it does. FDA compliance is determined by the FDA.
LPF is a hobbyist web site.
Common sense should tell you a 6mW laser is not 5mW or less no matter what anyone says or thinks.

Title 21 of the Code of Federal Regulations (CFR) Section 1040.10(b)(39):

“Surveying, leveling, or alignment laser product means a laser product manufactured, designed, intended or promoted for one or more of the following uses:
(i) Determining and delineating the form, extent, or position of a point, body, or area by taking angular measurement.
(ii) Positioning or adjusting parts in proper relation to one another.
(iii) Defining a plane, level, elevation, or straight line.”

"Hand-held lasers promoted for entertainment purposes or amusement also meet the second definition, that of “demonstration laser products” as defined by 21 CFR 1040.10(b)(13):
“Demonstration laser product means a laser product manufactured, designed, intended, or promoted for purposes of demonstration, entertainment, advertising display, or artistic composition.”

"21 CFR 1040.11(b) and 1040.11(c), limit surveying, leveling, and alignment, and demonstration laser products to Class IIIa. "
From:
https://www.fda.gov/radiation-emitt...rtant-information-laser-pointer-manufacturers

 

[RedCowboy]

Contact a product liability specialist, this is only a hobby website, legally binding anything is not available here.

 

[Encap]

Have a look at:
https://www.lasercompliance.com/cdrh-laser-compliance-consultants.html