How to estimate power of a 405 without an lpm?

[Emialias]

hello. new guy here, and i recently got a generic chinese laser 301 405nm and ive seen some things on sites that show what certain mw of 405nm can do
What can certain mW of laser do
this laser's beam is really visible from the side at night. even better from the users point of view. which according to this site means it is around 500mw+. that doesnt seem right since its just a $10 chinese pointer i got off of ebay. is the chart wrong? or is my laser waayy over spec? whats going on?

 

[Emialias]

also ive measured with a ruler with saftey goggles and the beam diameter is like, 3-3.5mm so i can imagine that it would be even brighter if the beam was that of a dpss green.

 

[Sta]

Welcome to the forum! We're glad to have you here, and we're glad you used safety goggles when measuring the beam.

Typically 405nm 301s are between 50-100mW. Yours is probably in that range - it is not unusual to see 405nm beams from the side. Can you tell the color of the beam easily when looking at it? If it's a grayish color, you're seeing using scotopic vision, and likely not more than 100mW.

 

[Emialias]

well i see it as a deep purple which is awesome because the only other place i see that color is with sunlight and a prism. so im guessing the charts on lazerer is somehow wrong or off?

 

[Sta]

well i see it as a deep purple which is awesome because the only other place i see that color is with sunlight and a prism. so im guessing the charts on lazerer is somehow wrong or off?

The dot or the beam? It's a very important distinction - you'll always see the dot as violet, but the beam may look like a dim gray if it's too weak.
Edit: That lazerer chart is probably wrong about the 500mW+. Besides -- unfortunately -- 500mW is out of the question for 301 lasers.

 

[Emialias]

nah its a violet beam, i dont really see any grey there. is that supposed to happen or am i seeing things wrong?

 

[Sta]

I just fired up my two low-power 405s, and both of their beams are actually deep purple! So you're not hallucinating. Yours is probably 50-100mW.

Unfortunately my 1W 405nm was killed in an explosion so I don't have anything brighter to compare my weak ones to.

 

[Emialias]

well this thread is dead now. the laser just went Zzzt and dimmed out. took the battery out and put it into a box labeled "Chinese laser graveyard"
the only survivor is my cheapo greenie
rip

 

[diachi]

well this thread is dead now. the laser just went Zzzt and dimmed out. took the battery out and put it into a box labeled "Chinese laser graveyard"
the only survivor is my cheapo greenie
rip

I don't recommend the 405nm 301s to anyone for that reason. I've had two die with only minutes of use on them. The 532s are a great deal for the price though.

 

[Alaskan]

I bought a 303 greenie here in Afghanistan yesterday for sale by a local vendor, these things are everywhere.

 

[GSS]

I bought a 303 greenie here in Afghanistan yesterday for sale by a local vendor, these things are everywhere.

I'm curious for how much? Not to derail and get into a political thing but i'm guessing there isn't any law enforcement issue's on typical civilian use?

 

[Encap]

I bought a 303 greenie here in Afghanistan yesterday for sale by a local vendor, these things are everywhere.

That you found them for sale there in and of itself is interesting--especially in a Country with a per capita income of $623.15/year.

As GSS asks--how much did it cost there?

Wondering if you brought any lasers with you or is that prohibited?