Um... oops

[iwannapony]

no it would instantly affect your eyesight, i wouldnt take time.

 

[HIMNL9]

Apart from the clearly and well explained dangers of IR, etc... :gj:
I think the most interesting word here is highlighted.

ROTFL !! ..... sorry, my bad, it had to be "diode", not "dilde" ..... LOL .....

Sorry again ..... :wtf: :crackup:

 

[Prototype]

...I'm not sure which one is more efficient.

Neither is more efficient than the other, really, efficiency only comes into play when DPSS lasers are the topic, as a 1W green probably has a 5-7W pump. With diode laser, there's no real loss of power excluding the lens drop. Greens are usually between 10-20% efficient, blues 3-5%, and yellows...well I'm not entirely sure, but it's probably not more than 2-3%.

 

[rangedunits]

more like 20% efficient for builts.

 

[Kewlguy]

Back to what he needs this laser for...

If what you want is to to transfer power from one point to another wirelessly, then I really really wouldn't recommend doing it with a green one, because greens are highly inefficient. The only reason they are so popular is because green is the most visible light to the human eye. If you want to efficiently transfer power, the best way would probably simply be with that IR diode. If you want to be able to see the beam, you should go with red (650nm) or violet (405nm). Red is cheaper than violet, but IMO violet looks cooler . I'm not sure which one is more efficient.

i would use IR..... but when I tried the IR beam i got 0V from it even all the way to 700mW (2.5V @ 300mA, potentiometer range from 6mA to 328mA). then again is it not the wattage you need to power the laser? should i decrease the voltage and increase current?

I'm not really caring about the efficiency of the laser itself. i'm more caring about the efficiency of the solar cells on the receiving end. i used 2 headlight backings to keep the beam reflecting onto the solar cells (works by the way. with a 5mW green laser I went from <1 mV to 2mV output voltage.

that ebay add was just for trickery.... it states blue also.. can you post pix of your diode and your whole set up?

michael

I can take a picture of the diode but i tore down the build because it didnt work. I only had a temporary set up to test everything out on a breadboard.

 

[Prototype]

Depending on the diode, IRs have a nominal Vin requirement, but a 1W should lase at 300mA, lasing threshold should be around there, but I'm no expert. Best of luck to you.

 

[hugo999999]

i would use IR..... but when I tried the IR beam i got 0V from it even all the way to 700mW (2.5V @ 300mA, potentiometer range from 6mA to 328mA). then again is it not the wattage you need to power the laser? should i decrease the voltage and increase current?

I'm not really caring about the efficiency of the laser itself. i'm more caring about the efficiency of the solar cells on the receiving end. i used 2 headlight backings to keep the beam reflecting onto the solar cells (works by the way. with a 5mW green laser I went from <1 mV to 2mV output voltage.




I can take a picture of the diode but i tore down the build because it didnt work. I only had a temporary set up to test everything out on a breadboard.

diodes are never this efficient, to get 700mw out of a diode you would have to use a lot more than 350ma, more than 700 (1w IR laser diodes take 1.5 A to make 1w of light, therefore to make 700mw light you will need at least 700ma). at 300ma you were powering the diode just over threshold current (250ma for these diodes) and i very much doubt it was putting out much power.

 

[hugo999999]

also with the photo voltaic cells i have heard that most respond to green best (or only in some cases) using IR may produce little to no results unless you have purchased a specific cell for this wavelength.

 

[electron]

If you have insurance, I would go to an eye doctor just to be sure, and if it starts to give you any problems I would then go regardless......your sight is nothing to mess around with.

 

[Cyparagon]

Yes, photo cells respond to IR. I do not know the response curve though. (But I bet a famous search engine does)

 

[Kewlguy]

diodes are never this efficient, to get 700mw out of a diode you would have to use a lot more than 350ma, more than 700 (1w IR laser diodes take 1.5 A to make 1w of light, therefore to make 700mw light you will need at least 700ma). at 300ma you were powering the diode just over threshold current (250ma for these diodes) and i very much doubt it was putting out much power.

Power in Watts = Voltage x Current

300mA x 2.5V = .... 700mW

to get 700mW using 1.5A i would have to use about 470mV

I don't see how it would matter if the wattage is the same whether you use high amps and low volts or high volts and low amps. It's easier and simplier to adjust current than it is to adjust voltage. producing the power isnt a problem.

I used Lumify's advice and sure enough i could see a light orange light coming outta the diode. The solar cells I got dont respond to IR light. so until i get a green laser diode or some crystal (still need to research that but probably start that up next week, finals this week). The research I've done so far leads me to believe that solar cells respond the most to green light, which is why I was trying to buy a green laser diode.

 

[diachi]

Just want to offer a little clarification, direct doubling is highly inefficient. Green is [usually] made using an 808nm pump, that lases an Nd:YVO4 crystal, which doubles the wavelength to 1064nm, and then a KTP doubles that down to 532nm. I say usually, because in some systems, such as a LaserScope, a KTP:YAG flashlamp system is used to produce the green.

Correction.

808nm pump diode pumps Nd:YAG/Nd:YVO4 which produces laser light at 1064nm ( in this case ), that is NOT double the wavelength. The 1064nm laser light from the Nd:YAG/Nd:YVO4 is then FREQUENCY doubled ( this means the wavelength is HALVED ) to 532nm ( green ) using some non-linear optic such as a KTP or LBO.

In a laserscope the process is the same, but instead of having a laser diode as a pump you've got a lamp, which still produces 808nm light and a whole mess of other wavelengths - just not in a coherent manner.

 

[BShanahan14rulz]

Don't quote me on this one, but I heard that wires are pretty good at conducting electricity from one place to another. Just a thought.

 

[diachi]

Don't quote me on this one, but I heard that wires are pretty good at conducting electricity from one place to another. Just a thought.

I believe he wants to do it without wires ... in which case a resonant transformer would work well.

 

[Prototype]

Correction.

808nm pump diode pumps Nd:YAG/Nd:YVO4 which produces laser light at 1064nm ( in this case ), that is NOT double the wavelength. The 1064nm laser light from the Nd:YAG/Nd:YVO4 is then FREQUENCY doubled ( this means the wavelength is HALVED ) to 532nm ( green ) using some non-linear optic such as a KTP or LBO.

In a laserscope the process is the same, but instead of having a laser diode as a pump you've got a lamp, which still produces 808nm light and a whole mess of other wavelengths - just not in a coherent manner.

Whoops, my bad

 

[diachi]

Whoops, my bad

Aha, had to correct you - don't want noobs getting the wrong information ...