Dye Laser Comes to Life!

[Anthony P]

I did the first test fire of the dye laser today. To my surprise, it worked the first time. All I could think was," Wow! That's a lot of yellow."

The cell itself is 4mmID x 110mm long. The electrode spacing on the lamp is 114mm. 1uF cap charged to 15KV. It even worked with the OC removed. With the OC in place the spot on target is cleaner and somewhat more intense. Dye is Rhodamine 590 chloide in 99.9 ethanol ( makes me wish I had not quit drinking...LOL). The beam is somewhat divergent as expected.

Moving forward, I need to figure out how to photograph output to get you guys some good pictures. Also, I will experiment with collimating lenses to tame divergence. There is more to do... but at least it works.

Merry Christmas

https://imgur.com/5jF06XM

 

[Lifetime17]

Hi,
And merry X Mas , nice job on your project need to see it in action.
Rich

 

[Singlemode Laser]

Nice!
Can't wait to see some beam shots.

Singlemode

 

[paul1598419]

Yeah, I need some beam shots too.

 

[CDBEAM777]

PICS....PLEASE !!! Yes....A trip in the " WayBack Machine " is in order here ( Thanx Mr. Peabody !!).....Back to 1970....There was an article in the Magazine " Scientific American " See the link !!! A Homebuilt Dye Laser.....I assume this is a variation of THAT build ??? BRAVO....Indeed !!! Congrats !!!

Working with both lethal current and carcinogenic dye-Rhodamine 590 ….WOW...…BIG DANGER in both areas....and then add DANGER to one's eyeballs with such optical power...…..I am justifiably impressed !!!! Be Careful...No SHit !! And do continue to share !!! Thanx !!!! CDBeam

See this link !! http://www.technology.niagarac.on.ca/people/mcsele/lasers/LasersFLP.htm

Peabody's Improbable History - Surrender of Cornwallis

 

[Anthony P]

This project is indeed based on the old SciAm article. A few decades ago I built the Sci Am version word for word. This version has several improvements over the original. The dye cell is a bit longer and has a smaller ID(4mm). I have gone to great lengths to minimize the parasitic ends of the cell... nearly its entire length is exposed to the flashlamp. The cell and lamp are close coupled. Also, the cap is higher voltage and lower capacitance(1uF, 20KV).

Currently, I am awaiting delivery of a vintage uA meter to monitor charge voltage. I am also fabricating mounting for an AixiZ module to add collimating optics.

I promise plenty of pictures when it is completed.

 

[CDBEAM777]

Oh Crap..... See pic !!!! My FIRST Coherent inspiration was based upon this SciAM article !!! Hmmmmm…….Clickamouse wants a Yellow source for Lumia...BADLY...Very Badly...SO...can we morph over to pulsed....to deliver the perception of CV...maybe at 2W intensity......Maybe we can have a " Poor Man's Yellow " ….or....am I completely ignorant about the physics here ???

I know the Dye cell must lase micro seconds before the thermal impact of the photon bombardment disrupts the couple state....so...maybe not possible at all...About these " Major League " Laser systems....I know very little..... But...they are beautiful !!...And...divergence as applied to Lumia is not important !!

Thanx....and keep us along for the build ride !!! It will be a real treat !!!

CDBeam

 

[Anthony P]

Oh Crap..... See pic !!!! My FIRST Coherent inspiration was based upon this SciAM article !!! Hmmmmm…….Clickamouse wants a Yellow source for Lumia...BADLY...Very Badly...SO...can we morph over to pulsed....to deliver the perception of CV...maybe at 2W intensity......Maybe we can have a " Poor Man's Yellow " ….or....am I completely ignorant about the physics here ???

I know the Dye cell must lase micro seconds before the thermal impact of the photon bombardment disrupts the couple state....so...maybe not possible at all...About these " Major League " Laser systems....I know very little..... But...they are beautiful !!...And...divergence as applied to Lumia is not important !!

Thanx....and keep us along for the build ride !!! It will be a real treat !!!

CDBeam

You are correct about it being pulsed. Continuous dye lasers are beyond my amateur scope. They are usually pumped by a 5+watt argon laser and the dye flows through a high pressure jet.
As far as the "poor man's" aspect goes, The capacitor was $450.00, the windows were $75.00 each, the quartz work was around $300.00, and the HR and OC ran about $300.00. Fortunately, I already had vacuum equipment and HV power supply.
It makes me laugh when I hear people whining about spending an extra dollar or 2 on good batteries.

 

[CDBEAM777]

Well...." PoorMan's" sounds lika bad choice of words on my part...ALL things are relative !!! ....But then....a DPSS/OPLS...or other professional grade Yellow with some decent PO...5~10 K ???
Now...If we made $$ with our hobby....well..." That is a Horse of different Colour " !!!

Well...Do regale us with your travels !!! I DO look forward to the education !!! CDBeam

 

[Arcygenical]

This is my "most anticipated to see a result" thread of 2019. I've thought about messing around with something similar, but I know I don't have the manufacturing capability to do so at my current domicile. I miss having 3 axis CNC machines, and not to mention the ability to acquire pure ethanol here is rather limited.

 

[diachi]

This is my "most anticipated to see a result" thread of 2019. I've thought about messing around with something similar, but I know I don't have the manufacturing capability to do so at my current domicile. I miss having 3 axis CNC machines, and not to mention the ability to acquire pure ethanol here is rather limited.

You don't need a CNC or pure ethanol. Check the link in my signature.

 

[Anthony P]

Indeed, pure solvents are not necessary. I have read of people successfully using vodka or rubbing alcohol. Use of pure solvents just eliminates a variable... one less thing to worry about.
As far as CNC, the most sophisticated tools I own are a vise and drill press. The trick is that anything that requires precise alignment needs to be designed to be adjustable.

 

[diachi]

Indeed, pure solvents are not necessary. I have read of people successfully using vodka or rubbing alcohol. Use of pure solvents just eliminates a variable... one less thing to worry about.
As far as CNC, the most sophisticated tools I own are a vise and drill press. The trick is that anything that requires precise alignment needs to be designed to be adjustable.

Yup, I used both ethanol and ispropyl alcohol from the pharmacy, and if I recall correctly had some success with tap water. I didn't even use any tools to get a basic dye cell lasing. Though proper mounts/optics etc would certainly have improved results.

 

[paul1598419]

Yup, I used both ethanol and ispropyl alcohol from the pharmacy, and if I recall correctly had some success with tap water. I didn't even use any tools to get a basic dye cell lasing. Though proper mounts/optics etc would certainly have improved results.

Reminds me of a video planters posted of a dye laser he built. That was a few years ago, but he had the dye circulating through at a fairly high rate. His output power was quite high. He used optics to enhance the output and beam quality of his system. If anyone is interested it is likely still on YT.

 

[Seoul_lasers]

You are running a Nitrogen flash lamp as your pump source?

 

[Anthony P]

The flashlamp is filled with plain old air... so mostly nitrogen. As per Lankard's design, the cap is charged and then the lamp is rapidly evacuated til it fires. The cap is 1uF charged to about 15000v. In the past, I have experimented with a lamp backfilled with pure N2 and triggered by HV coil. I remember that it was difficult to find the correct backfill pressure to get reliable operation. Also, there was no significant change in performance in the N2 lamp vs air lamp.
A completely separate project was the N2 laser pumped dye cell. This one was easy. It just wanted to work. There was no resonator and alignment was merely nudging the cell around to find the sweet spot. Power was low, but reliable.
The flashlamp version has much more power output!
I have spent the past few weeks experimenting with different ways to monitor the charge on the cap. These include a gig-ohm voltage divider, an op amp buffer, and a uA analog meter. I am awaiting a digital uA meter with its own power source to combine with 100Meg HV resistor. I have high hopes this will resolve metering issues.
While waiting, I am fabricating mounts for various collimating lens configurations.

The process is slow, but after all, it is a hobby. I am not on a schedule or deadline. Also, I have a day job.