PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please sub

[Alaskan]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

You mean not doped for diode pumping?

 

[diachi]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

It doesn't look doped to me. I think the purple in the 5th pic is due to the AR coating. The Spectra-Physics labels also give no indication of doping type or concentration.

Mirror coatings suggest it's a gain crystal though.

Colour could be due to a very low end dopant percentage.

 

[Alaskan]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

If I remember correctly, that little YAG is about the same size as the one used in this laser head which is pumped with 2 watts of 808 nm

Spectra Physics 7960-L4-E Laser | eBay

 

[diachi]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

If I remember correctly, that little YAG is about the same size as the one used in this laser head which is pumped with 2 watts of 808 nm

Spectra Physics 7960-L4-E Laser | eBay

Possibly, they used a 5mm long crystal in those. Some heads had a higher pump power specification depending on the head, I'm not certain on the exact figure but I think it may have been up to 4W for the >1W output models.

 

[Alaskan]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Might be I'm remembering incorrectly, 4W does have a familiar ring to it. In any case, 1 watt of 1064 nm output isn't much for my likes.

 

[ultimatekaiser]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Mostly Yag crystals are usually about 1% doped but plenty are much less. There are undoped ones but pretty uncommon to run into. Anything longer than a few millimeters is usually side pumped-end pumping isn't very efficient. Also keep in mind that you generally can't see the pinkish Nd color unless it's under sunlight. Not a lot of light sources cause the nd to show its' color. This is in fact one of the reasons that is used in jewelry and some windows-as it gives it the appearance of changing color!

 

[paul1598419]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

I was going to say that this is probably less than 1% doped, so the color would not be obvious. Matt beat me to it, though.

 

[Alaskan]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Item of interest, but not enough to buy. Looks like he is knife edging several diodes to get this. Price far too high for what it is:

520nm 10000mW/10W Green Laser Module/TTL Modulation | eBay

 

[CurtisOliver]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

I've seen better and cheaper from Golden Star. You can get a similar laser for $2500 there.
The beam width is slightly larger, but the divergence is better.

OEM-520-10W

But could you imagine 10W of 520nm. :drool:

 

[paul1598419]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

I've seen better and cheaper from Golden Star. You can get a similar laser for $2500 there.
The beam width is slightly larger, but the divergence is better.

OEM-520-10W

But could you imagine 10W of 520nm. :drool:

They claim a transverse mode of TEM00. That is ridiculous. Also call the 10w an 8 watt further down in the description. Don't know what parts to believe and which to ignore.

 

[CurtisOliver]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

They have obviously made a typo in their listing. Golden Star is a reputable company. Well, they shouldn't claim that the entire output is TEM00, but at least the individual beams are.

 

[paul1598419]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

How would they get a TEM00 out of knife-edged 520nm diodes? Even a single 520nm diode doesn't give TEM00.

 

[CurtisOliver]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Well technically you are correct Paul. Alaskan's link has near TEM00 as a description.

 

[paul1598419]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

I guess the "near" TEM00 is the disclaimer for those who know the difference. It is a $7,000 knife edged 520nm laser. It isn't possible to get TEM00 out of direct diode lasers, no matter what optics they use. So, what in the world does "near" TEM00 mean?

I'd rather go for this. It can have near TEM00 and they claim the divergence is 1.5 mrad full angle. Ten watt 532nm DPSS laser for $5,980.00

www.ebay.com/itm/262852361624

 

[Alaskan]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

I saw that listing for the DPSS. I don't know what application the 7K knife edged multi diode unit would be, but I'd consider it as a toy for much, much, less of a price.

 

[paul1598419]

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Yeah, it isn't even polarized, but they claim a 100:1 polarization like a DPSS. It is pretty much useless as a test laser. It makes no sense at all.