Sharp 505nm

[Singlemode Laser]

I don't have an exact number for it, but it is longer. Maybe 5 mm or there about. If I understand your other question correctly, they are ~ the same aperture.

If you are talking about the f number... both lenses have the same diameter and the FL are as described.

The lower NA (~ to Aperture/FL) could be one reason. To avoid clipping the NA of the lens should be higher than the one the diode. Another reason for the clipping with the short FL lens could be beam distortion introduced by the diode's window. Depending how thick it is, it will add a beam displacement if the diode front facet is not exact parallel to the window and/or the window has a wedge.

Since the lens with the higher FL but the same apperture produces a "better" beam, the lens maybe just clips the artefact?

Singlemode

 

[paul1598419]

That's disturbing. It does look like the window of the diode, and clipping is not how I want to manage that. I guess I'll have to make some careful calculations to see where the window sits with respect to the axis of the lens. It has been an on again off again problem around here for awhile. I haven't had it as badly in the past, but these Sharp diodes seem to bring it out very clearly for everyone who has dealt with them.

 

[Singlemode Laser]

That's disturbing. It does look like the window of the diode, and clipping is not how I want to manage that. I guess I'll have to make some careful calculations to see where the window sits with respect to the axis of the lens. It has been an on again off again problem around here for awhile. I haven't had it as badly in the past, but these Sharp diodes seem to bring it out very clearly for everyone who has dealt with them.

This lens is not too expensive:

https://www.lasertack.com/asphaerischer-kollimator

And has an NA of 0.6. This is almost as high as it gets with aspheric diode laser collimators. It has a great btoadband AR coating and can be used for almost all visible diodes.I am sure you can find some cheaper alternatives after some searching.

I will make some pictures next week with a 4,5 mm and a 3,1 mm lens.

Singlemode

 

[paul1598419]

They are sure proud of that lens. 39.00 Euros is a lot. They don't even say what the lens material is. I'd like to think it is glass, but that is not apparent. I might be able to find a similar one for less. Just going by the prices for their other products that are identical to ones I know are less. The housing is very short too. 8 mm. It does have a good numerical aperture, but it isn't so unique to justify the price they are asking. I'm looking forward to your photos of the lenses you use. If it shows up, you'll know it immediately. There's no mistaking it at all. Thank you for the link, Singlemode. I need to do some hunting to see if I can get the same thing elsewhere. You are sure this won't show the artifact? I'd hate to pay ~$48.00 for a lens I can't use.

 

[Singlemode Laser]

They are sure proud of that lens. 39.00 Euros is a lot. They don't even say what the lens material is. I'd like to think it is glass, but that is not apparent. I might be able to find a similar one for less. Just going by the prices for their other products that are identical to ones I know are less. The housing is very short too. 8 mm. It does have a good numerical aperture, but it isn't so unique to justify the price they are asking. I'm looking forward to your photos of the lenses you use. If it shows up, you'll know it immediately. There's no mistaking it at all. Thank you for the link, Singlemode. I need to do some hunting to see if I can get the same thing elsewhere. You are sure this won't show the artifact? I'd hate to pay ~$48.00 for a lens I can't use.

I can't guaranty, that this lens won't show the artifact. I just know, that this is the same lens that I am using (from Thorlabs) but just in a different housing for half the price.

(That is one of the lenses I have in the lab and I don't have to pay for that. If I should trade off between buying a lens with my own money and the quality of the product for a cool hobby, I don't know what I would do)

 

[paul1598419]

It's a little bit more than a cool hobby for me. I have spent quite a lot on test equipment and many diodes, gas lasers, DPSS and all sorts of optics. I am retired now and since I do this on my own now, I have to watch what I spend. I was an electrical engineer for many years and know what it is like to have money to spend on my every need. I quit doing everything concerning circuits for a few years after I was no longer employed. But, I used to make holograms back in the early 1980s and sort of got back into lasers after I found that I needed to do something besides just waiting around to die. I found my way to this forum about four years ago and I have been learning more about lasers than I ever did before and found it gives my life some meaning. Anyway, it is more than just a cool hobby for me. I don't mind spending the money if it is necessary. It sounds like this lens might be better than I thought it was. I will wait to see your photos and make my decision after that.

 

[Dr.Laser]

Single Mode Sharp GH05035A2G Green Laser Diode 505nm 35MW : High Power Burning Laser Pointers,DPSS Laser Diode LD Modules, Kinds of laser products

Looks like they have a final version of the datasheet.

This datasheet acknowledge the markings on the diode.

The interesting thing that the format is SB14XXXXX which suggests the ones we are getting from ebay (SB15) is likely a different diode.

The wl range is specified at 500-515nm. Also it seems that different batches are made in different countries. It could be either made in Japan or Taiwan.


Also BeamQ sells Osram 488 and Sharp 495.

 

[jnrpop]

Very likely!
The ebay diodes having a completely different internal circuit, case positive, photodiode etc...

The 505's i believe originally came from Song in China. Two batches. The first ''Test" batch members got <505, only a handful of diodes were available.

Then Song ordered a new batch to meet supply, this second batch yielding results above 505nm. The second batch i believe was the supply of DTR, and a few other members here also received diodes from the second batch.

The 505's from Tech/Newg/Exis i have no idea.... but its not so common to have diodes with the micro-printed numbers on the window edge.....possibly indicating its from the same source as the originals.....Sharp factory???

Edit: BeamQ has the Osram PLT5-488's for $299

Group buy?

 

[ZRaffleticket]

There we go. A public listing for a <$300 price tag on these things.

And yes -- that is the case on the 505nm diodes

 

[Atomicrox]

Depending on the discount I might be in.
Also their price for the sharp 495nm indicates it might be the real thing (as opposed to the misbranded 488nm diodes that showed up on ebay).

 

[Albert1007xd]

Depending on the discount I might be in.
Also their price for the sharp 495nm indicates it might be the real thing (as opposed to the misbranded 488nm diodes that showed up on ebay).

Same here.
Depending on the discount, I'm in.

 

[Singlemode Laser]

Edit: BeamQ has the Osram PLT5-488's for $299

Group buy?

The prices on this side typically higher than the contacts of the forum members. Lets hope we can push the price on our group buy we allready started to organize!

 

[ZRaffleticket]

The next (known) lowest on these diodes is at $280, from whoever joeybab was in contact with. $20 more really isn't much. I couldn't find them however...

 

[jnrpop]

The next (known) lowest on these diodes is at $280, from whoever joeybab was in contact with. $20 more really isn't much. I couldn't find them however...

Couldn't find which diode Z?

PLTB-488 - BeamQ
Osram PLT5 488nm 60mw 5.6mm Laser diode LD : High Power Burning Laser Pointers,DPSS Laser Diode LD Modules, Kinds of laser products $299.00

but i can't work this one out :thinking:

a 488nm diode from the same website/seller but no manufacturer name??
488nm Laser Diode 60mW
And its $7,800.00

EDIT: but this is a 505nm thread :crackup:

 

[paul1598419]

Well, I just got four more SB1573N91 diodes to measure today. I don't know about these new sources for a 488nm or 495nm diode, but I wouldn't get terribly excited just yet.

 

[Singlemode Laser]

Well, I just got four more SB1573N91 diodes to measure today.

Do you already the WL results?

Singlemode