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Brightness In Lumens ?

biddy79uk

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This might sound a silly question and maybe also contradicting myself here,
But in a projector is the Brightness In Lumens - 2400 = 2.4W diode if extracted & used on a custom build ?
Thanks Guys
 

chipdouglas

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no.
projectors do not have 1 diode. I believe there are 24.

Michael.
 

biddy79uk

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Thanks for the quick prompt reply Chipdouglas :)
I thought RGB projectors had only 3 as in RED > GREEN & BLUE ?

I didnt mention it was a RGB in my OP but you answered my question anyway and thank you pal
 

chipdouglas

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well I've been out of the scene for a few months. there could be a new projector on the market.. but in the typical one we use/harvest from there are 24 blue lasers, 1 red led. and one phosphor wheel. The blue lasers emit the blue light, and also hit the phosphor wheel to create the green light.

Michael.
 

biddy79uk

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Well on another note,
Can anyone sugest a decent projector that will output 1 Blue diode around 2+W
As i'v seen many posts regarding using diodes from projectors to build a decent laser
Thanks again Chipdouglas + 1 Rep
 

shokkunlasers

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This might sound a silly question and maybe also contradicting myself here,
But in a projector is the Brightness In Lumens - 2400 = 2.4W diode if extracted & used on a custom build ?
Thanks Guys
Ok where do I start

First Lumens aren't only dependend on optical power that's what we measure our lasers in. (yes I know we measure thermal power givin to the sensor but the LPM should give us a rather exact information about the optical power )

Lumens are a unit for the total light a lightsource puts out and how bright our 'standard' human eye perceives it for example a lightsource with 100 lumens 532nm light has a different optical output than another with 100 lumen but another wavelenght like 445nm because our eyes perceive it different

For a projector it's way more complex than that because because you have three different lightsources with different optical powers (or a HID with a color wheel ) One of those three (RGB) lightsources are our 445nm diodes they are focused on a spinning phosphor compound wheel which then produces green light via flurescence (they make the green light that way because led's are not good/efficient enough nowadays) in this process you lose optical power but get more lumens because green is perceived better.

Anyway the lumens in the datasheet has nothing to do with the power of the laser diodes. If you are experienced like DTR or so you could maybe guess it.

BUT never calculate it without already knowing everything aka lumens of red and blue leds after all optics and the lcd... conversion efficiency of the phosphor wheel and so on
 

biddy79uk

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That was a pretty nice read mate and educated me enough to now realise the difference
thank you mate :)
 

shokkunlasers

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Well on another note,
Can anyone sugest a decent projector that will output 1 Blue diode around 2+W
As i'v seen many posts regarding using diodes from projectors to build a decent laser
Thanks again Chipdouglas + 1 Rep
I see you are new here.

Yes we all using diodes from projectors but only very few disassemble them because it's difficult you need special tools and experience and more obvious nobody needs nor want to afford 18 9mm diodes or 24 m140 diodes for private use.

Nearly everybody buys them from DTR he does this for a long time is very professional and you won't get a damaged diode or something.

His site:https://sites.google.com/site/dtrlpf/
 

biddy79uk

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Yes mate i'm very familliar with DTR and hes site but never really needed nor wanted to start my own build's,
Its far cheaper to buy the diodes/driver's etc and build yourself but i simply dont have time,
Not even as a long lasting hobby "hence" the reason i'v bought pre-builds from Blord and such...

But now i have time on my hands i'm contemplating to start my own 1st custom build using DTR's Osram PLTB450 1.4W 450nm Diode In Copper Modules W/X-Drive & G-2 Glass Lens and a 501b host until i can get my friend to make my heatsink for a custom host.

I'll add pictures of the host and heatsink along with the finished product when i get time,
my friends a genius on a lathe :)
 

Cyparagon

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This has been discussed a few times before. You look up on the CIE tables the lumen/watt value of a wavelength and you can determine the luminous flux. A watt of green for example is about 600 lumens.

Here's a chart to give you an idea

 
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