Sharp GH04W10A2GC 350mW 405nm

[CurtisOliver]

Unfortunately it has to be remembered that laser diodes are commercial products. Therefore as a product, it has to have a market/application to make them commercially viable. High power multimode diodes 450nm’s are used in projectors. I can’t think of any applications of the top of my head that would warrant a 5w multimode 405.

 

[RedCowboy]

Super high speed blu-ray burners could make use of stronger 405's, what's the top end right now 16X ?
How about a 32x or 64X....maybe a 128X ???
Sure the disc may pop out looking like a warped wet paper plate, but faster is better..... Right?

 

[CurtisOliver]

You would want single mode though I would of thought for data storage?

 

[RedCowboy]

Well it's only going to focus down to a fine point at a set distance so as long as the burns into the disc are within spec then it wouldn't matter, they could employ some masking as well.

I would rather have a 2w single mode but if they can make a 2w multi mode work and it's cheaper and easier to build then we get what we get, I am ready for bigger stronger what ever we can get.

How cool would it be if they combined 2 beams in a nice little package for us


---edit---

Actually they might just converge 2 x 405's onto the same footprint so it wouldn't be useful to us, a bigger diode either single mode of mm would be better.

 

[Richie89]

im thinking of ordering one of these soon, do you think 1250ma is too much current for this to be switched off and on with a regular tailcap switch? or should I drop the current to 1 amp. I really don't want to to be honest, I want more photons thanks for help

 

[Shotgundrums]

im thinking of ordering one of these soon, do you think 1250ma is too much current for this to be switched off and on with a regular tailcap switch? or should I drop the current to 1 amp. I really don't want to to be honest, I want more photons thanks for help

I was contemplating an order as well, Richie.
I haven’t been frequent here myself. Since I’ve put on master sgt I’ve been jumping around shifts and stupid busy
Only time, trial and error will tell what these diodes will handle. My recently installed 12x, which replaced a 16x, took a poop. I’ve driven both modestly... some last and some don’t it seems. My Black Nasty has been driving diodes with one of SL’s bucking regulators. Now for a New Diode
SGD

 

[Sumfinclever]

Lol perfect timing! I actually just finished a build with one of these today.

 

[RedCowboy]

The beam looks good in the pic, is it that visible to your eye ?

 

[Sumfinclever]

The beam looks good in the pic, is it that visible to your eye ?

Yes it is, very much so. Here it is next to one of the smaller 445nm pens with the same 1.4W output that I posted a while back. Also this is without vapor in the air.

 

[wolfram]

Hi Sum, I hope that you are enjoying the violet beast. I have run them above 1W...........Had one running at 1.6W and it died after 30 minutes. I think a a couple with cubes is safer. I do have one diode still running nice after 4 months at 620 mA=950-1W with a G2. Certainly not as powerful as 1.6W but good for the investment.

 

[Singlemode Laser]

Well it's only going to focus down to a fine point at a set distance so as long as the burns into the disc are within spec then it wouldn't matter, they could employ some masking as well.

I would rather have a 2w single mode but if they can make a 2w multi mode work and it's cheaper and easier to build then we get what we get, I am ready for bigger stronger what ever we can get.

How cool would it be if they combined 2 beams in a nice little package for us


---edit---

Actually they might just converge 2 x 405's onto the same footprint so it wouldn't be useful to us, a bigger diode either single mode of mm would be better.

The whole point in going from IR CD burners to the 405nm for Blue-ray is the reduced focus size. This however only holds for a single mode
laser (Gaussian beam or 00 mode). A multi mode laser diode would have a focal size multiple of the one from a singlemode diode and would
result in a fast CD burner but not a faster blue ray one.

Singlemode

 

[wolfram]

You can use a microscope lens

 

[RedCowboy]

The whole point in going from IR CD burners to the 405nm for Blue-ray is the reduced focus size. This however only holds for a single mode
laser (Gaussian beam or 00 mode). A multi mode laser diode would have a focal size multiple of the one from a singlemode diode and would
result in a fast CD burner but not a faster blue ray one.

Singlemode

I understand how the bandwidth of 405 means more digital info per given length of track and how writing thinner tracks means more info per disc however I am talking about using a stronger multi mode diode and they are likely using a circularizing lens such as the 405 pulls junktronix was selling that means the multi mode higher output diode could be used to read/write in the same size spot/footprint on the disc. It wouldn't yield a truly round/Gaussian beam but a suitable roundish footprint at the tiny disc read/write distance.

 

[Singlemode Laser]

magnification.png[/IMG]

I understand how the bandwidth of 405 means more digital info per given length of track and how writing thinner tracks means more info per disc however I am talking about using a stronger multi mode diode and they are likely using a circularizing lens such as the 405 pulls junktronix was selling that means the multi mode higher output diode could be used to read/write in the same size spot/footprint on the disc. It wouldn't yield a truly round/Gaussian beam but a suitable roundish footprint at the tiny disc read/write distance.

You are not right here. A multi mode diode just can't be focused to the same spot as a singlemode diode in the case of a diffraction limited spot. All optics in world would not change this. More power would burn bigger spots, and that's it. This is also the reason why the blue ray was developed instead of higher power IR diodes for the CD burners. Shorter wavelengths can be focused to smaller spots -> more information per area and higher data rate with the same rotation rate of the disc.

Thanks for pictures, there are nice to look at.

Singlemode

 

[Singlemode Laser]

You can use a microscope lens

No you just can't beat the physics here:

Airy disk - Wikipedia

en.m.wikipedia.org

and for non Gaussian beams:

M squared - Wikipedia

en.m.wikipedia.org

"The diameter of the multimode beam is then M times that of the embedded Gaussian beam everywhere, and the divergence is M times greater, but the wavefront curvature is the same. The multimode beam has M2 times the beam area but 1/M2 less beam intensity than the embedded beam. This holds true for any given optical system, and thus the minimum (focussed) spot size or beam waist of a multi-mode laser beam is M times the embedded Gaussian beam waist."


Singlemode

 

[Richie89]

Lol perfect timing! I actually just finished a build with one of these today.

hey buddy, sorry I havnt gotten on facebook lately so I havnt been able to respond back to you yet but im about to do that

I was contemplating an order as well, Richie.
I haven’t been frequent here myself. Since I’ve put on master sgt I’ve been jumping around shifts and stupid busy
Only time, trial and error will tell what these diodes will handle. My recently installed 12x, which replaced a 16x, took a poop. I’ve driven both modestly... some last and some don’t it seems. My Black Nasty has been driving diodes with one of SL’s bucking regulators. Now for a New Diode
SGD

oh nice a promotion?
that's okay buddy, ive been trying to get on more, "took a poop" Lmao! ive blown many diodes the past couple years, i remember when Paul said I would blow my fiar share of diodes in time and I was like "yeah sure I will" well.....he was right LOL! well im certainly contemplating buying one as well I think I will within the next week, gota wait for payday. but a 2W capable 405nm O.O would love that for sure.