Sharp GH04955A2G/ The New 495nm diodes

[styropyro]

I'm using an acrylic lens for both builds. And yes that artifact is visible in person, although it isn't a bad as the picture makes it out to be.

The leadlight one has a flex drive. In fact I had no working flexdrives on hand, so I cobbled together a working one from two damaged ones. It looks ugly but those components are so tiny that I couldn't make it neat and tidy. The higher powered one uses a microboost. Wish these drivers were still sold, and if anybody has extras on hand I'd be interested in buying some!

 

[paul1598419]

I guess "bad" is in the eye of the beholder. I see that rectangular artifact very easily without using a camera and its presence drives me nuts. I have tried to find a glass lens that eliminates it completely, but without success. Only the acrylic lenses seem to eliminate it, so until I am shown one that does, I guess I will continue to use acrylic lenses for these diodes.

 

[ZRaffleticket]

Same for me. I wish I had longer acrylic lenses. Can't really use my focus adapters with them since they sit so close to the diode.

 

[BowtieGuy]

Has anyone tried the 'two element 520nm' lens that DTR sells? :thinking:

 

[styropyro]

Same for me. I wish I had longer acrylic lenses. Can't really use my focus adapters with them since they sit so close to the diode.

I get around this by wrapping a loop of soldering wire around the aixiz lens barrel to make a loop, then taking it off, squeezing it so it is a little bit smaller, and then putting that ring in the focus adapter so there's a gap between the adapter and lens barrel. It usually takes two little loops of wire to get enough separation. It works well though, so I can focus the laser to infinity without the focus adapter hitting the module.

Edit: oh yeah, USPS didn't get that package to me today.

 

[Lifetime17]

Same for me. I wish I had longer acrylic lenses. Can't really use my focus adapters with them since they sit so close to the diode.

Hi Z ,
Try using a normal lens barrel and see if the acrylic fits in it , That should give you some FL.

@ Bowtie,
I will try a 2 E tonight and check back in. I have them..

Rich

 

[paul1598419]

Same for me. I wish I had longer acrylic lenses. Can't really use my focus adapters with them since they sit so close to the diode.

I use fingernail polish to hold the lens assembly on the focus ring by adding it to the edge of the focus ring and turning the lens housing just enough to grab the lens. It works very well, and if you happen to make a mistake, it comes off easily with acetone. I have used this for years and it works every time. Just let it set up for an hour or so.

 

[Eracoy]

Has anyone tried the 'two element 520nm' lens that DTR sells? :thinking:

I use that lens for all of my lower power greenish builds. They are better for the divergence than a G2, but obviously don't transmit quite as much light. I would say anything above ~470nm would be a good candidate (I don't have the numbers on the AR coating).

 

[paul1598419]

The problem is with these Sharp diodes. They have a rectangular artifact on the side of the dot (beam profile) with any glass lenses I've tried. It isn't a problem with power output.

 

[ZRaffleticket]

I wonder if I could get a tiny o-ring to put in there. If not I'll try your idea Paul, and if that isn't good I'll try Rich's idea to take some apart. I have one with a cracked lens I think...

 

[paul1598419]

The acrylic lenses have a different FL than other lenses. If you try putting it in another housing, you need to be aware of that. The nail polish works fine, but have some acetone around if you don't get it on the first try. You need to turn the lens assembly just enough to catch. Then pull on it and set it lens down on something that will hold it up by the focus ring you are using. Then wait at least an hour to allow it to set up.

 

[DrMario]

Oh well, I am not too worried about the artifacts in the beam, I have the Sharp 505nm laser diode. I would still use glass lens since I want my Emerald green laser to last a good while (I am kind of wondering about the storage longevity on the optical Acrylic material).

 

[paul1598419]

At these powers, and kept out of the air where dust and dirt can get on them.....indefinitely. I have builds with these lenses over 4 years old and still working fine.

 

[DrMario]

Makes sense. I have been wondering about that. I wonder if the air bulb usually used to clean the DSLR camera optics will work also, if the Acrylic lenses get dirty.

 

[paul1598419]

I would think so. But, it's better not to allow it to get dirty in the first place.

 

[DrMario]

Completely true.