DYE help

[Alaskan]

I'd like to have a dye laser to use with my 10 watt 532 nm DPSS to make yellow, but they are so darn heavy. How much does this one weigh?

 

[Jim H]

I'm guessing 75-100 lbs for the head and circulator.

 

[Alaskan]

HEAVY.... OK, thanks. Anything I get here in Qatar needs to ship via USPS, I'm looking for something lighter.

 

[Jim H]

After delays, the dye and ethylene glycol are finally shipping. Then play time begins

 

[kecked]

Ok I work with dye all day. I can provide the mix for the coherent I use but it works pretty simple. The alignment is a real pain but yours look simple compared to mine. I pump with 2w 532nm and get 30mw cw. I however have it setup on a cavity dumper and do picosecond pulses with it.

R6 on mine goes from 550 ish to 670 ish on a good day.

Is that a jet? Make sure the flow is perfect in the jet or your done before you start. I ping the 532 on the jet and add dye till you see fluorescence. Then you have to align the jet angle to the other mirrors to form the cavity and ring. It aint this simple But it’s the general idea. If you really want to know it’s best on a phone call. Wear gloves this dye is horrible. Also make sure the pump filter is new and the dye up to pressure before you start the jet. If all you want is some yellow buy one of the units being sold on the forum. Dye is a MAJOR PITA!

 

[Jim H]

Ok I work with dye all day. I can provide the mix for the coherent I use but it works pretty simple. The alignment is a real pain but yours look simple compared to mine. I pump with 2w 532nm and get 30mw cw. I however have it setup on a cavity dumper and do picosecond pulses with it.

R6 on mine goes from 550 ish to 670 ish on a good day.

Is that a jet? Make sure the flow is perfect in the jet or your done before you start. I ping the 532 on the jet and add dye till you see fluorescence. Then you have to align the jet angle to the other mirrors to form the cavity and ring. It aint this simple But it’s the general idea. If you really want to know it’s best on a phone call. Wear gloves this dye is horrible. Also make sure the pump filter is new and the dye up to pressure before you start the jet. If all you want is some yellow buy one of the units being sold on the forum. Dye is a MAJOR PITA!

I appreciate it! when I was running it when I first got it, the jet wasn't perfect. I found a piece of black something stuck in it, and got it cleaned out. After that, it looked smooth. I just didn't have a good pump laser at the time. The filter is in a sealed canister I think... So I will have to find one online then. I will PM you when I am ready to go. Are they 1 micron filters? I haven't looked at it in a long time, and don't know if it says or not.

 

[kecked]

Those filters can be hard to find. I have cleaned them by soaking in methanol but it’s not optimal. Run some methanol in the pump and see if you can clear it and get a good pressure. Mines 30-40psi

ifyour jet plugs it’s a bear to clean. You can bend and ruin a jet very easy. Also the fittings can leak and the jet can spray on occasion so put something under it.

more dye is not better! Also make sure you run the pump at least once a month.

 

[kecked]

Hey see if you can get it run off 520nm 1w diode. I do know it can be done. Try 445nm too. I also know the optics are a challenge to make multi mode diodes couple. If you get it it will be cool. We use a 20k laser pump.

 

[Jim H]

The jet is made of quartz, so it doesn't bend. The pump will get to at least 100 PSI, so the filter is not plugged. I can try flushing it. I am using coumarin 30 dye, which has a max absorbance at 412 nm, because my high powered laser is a 405, and it has a range of 488-555, with 555 being within the optics range. I just hope the input mirror works at 405. I haven't tested it yet...

 

[kecked]

My jet is metal. Well try it and see what happens.

 

[Jim H]

I drug everything out just to play around with it. The primary mirror allows quite a bit of 405 to pass through, but it also reflects quite a bit. Fixed a leak at the top of the filter, and as I didn't have much in the way of dye in it, and very diluted at that, I had to mix in some antifreeze as I wanted to keep everything as ethylene glycol before starting it up, and I wouldn't have enough liquid otherwise. I tried to adjust the primary mirror as best as I could, using a piece of paper to see the spot location and size using my 60X. I then reversed the laser, and shone it into the output, and tried adjusting the secondary mirrors by observing the spots on each, and trying to adjust them into one spot. Not sure that it is necessarily correct, but to me it seemed it should at least get them a lot closer to the correct position than they were. The manual that I have is actually an Aurora manual, so is fairly correct for the Lexel 350. Looking at everything carefully, it is actually a linear configuration, and not a ring, which I guess was an option. I found some old filters that I had bought ages ago from Edmond Scientific, and looking at the transmission graphs, the deep red didn't pass much yellow at all(0 on the graph up to 600 nm). So I cut a strip and put it inside my argon goggles. I tested the pump, adjusted the flow and got a good steady, although somewhat cloudy stream. I fired up the 405 and tried to adjust and focus it as best as i could. I didn't really expect any lasing from the dye, both due to the high dillution, and the low absorption of 405 by R6G, which is the left over dye that was in it. But it still fluoresced very brightly. The goggles and the filter made it easy to look at, and did a very good job of blocking almost all the produced light. I took a few photos of it. I will still need to clean the optics, but I didn't have lens paper, but do have some 99% alcohol. I will still also need a filter, and need to flush it out well before my new dye comes.


Unfiltered, with my phone.

Not very focused, but through the goggles. It isn't nearly as bright as it looks.


The best photo I could get of the jet. The focused spot is actually very small.

 

[kecked]

That’s essentially what you do. I don’t know your laser. On mine I have two spots I have to line up. Your on your way.

 

[Jim H]

Guess I know what I will be doing this weekend.

 

[Jim H]

Well, I still haven't had time to try my new dye out yet. I still need to clean out the old. Life, spelled with a w has gotten in the way, lol. But today I put the tiniest bit of dye in some isopropyl alcohol and put it in a small pyrex vial. It hardly has any discernible color, just the slightest yellow tinge, but it fluoresces very brightly in the 405 beam, even with my least powerful pointer.

How bright the pointer is on a white label spot on the vial, in reality, a bit more purple.

The exact same exposure with the beam going through the solution, and close to the actual beautiful aquamarine color. Maybe this weekend, if I get my car fixed......

 

[atomd]

Few remarks from my own dye laser experience.
1. dye is mess. Unless you really need tuning (and can't afford OPO) or you really need mode locking (and can't afford TI:sapphire) dye laser is just bad choice
2. This units have dichroic mirrors for coupling. Input coupler is most probably made to has 532nm pump and reflect everything below (basically mirrors for rhodmaine). This means you'll have high losses on input coupler when trying to get cumarine or any other <532nm dye to lase. You can swap input coupler but as multiple people already said this things are not in production for long time and unless you hit jackpot in surplus it'll be extremely expensive purchase.
3. High power 405nm lasers are multi mode and their focal power density is much, much lower than TEM00 beam this things are designed for so I think even with proper input coupler you won't be able to get it to lase. There's a reason dye lasers are either pumped from solid state lasers or from OPSL.
4. Your best bet is to actually try rhodamine pumped with either high power 532nm source or nitrogen laser (yes it has poor absorption but nitrogen laser has peak power in teens of kW or more). Problem with nitrogen laser is that pulsed dye laser is simply built from cylindrical lens and cuvette.

TLDR
The only reasonable way to get it working is to get quality, multiwatt 532nm pump and rhodamine. Or give it to someone that has suitable pump.