my dye laser project [ pic heavy ]

[Analysis]

I have achieved yellow light!
Unfortunately this thing would still be more effective as a sieve and no lasing to report yet.

This is a very advanced project. Just a few tips:

• You need a really clean, dark, temperature stable, vibration isolated environment. Fix your pump laser with a clamp on the desk. Put the dye pump on a vibration isolated block eg. polystyrene foam on the floor
• clean your optics with high purity acetone and methanol and lens paper. Be very carefull. Every scratch is irreparable. Just put a drop on the lens paper and pull it just once over optical elements, never tiwce. Every grain leaves scratches. Never push, gravity on the thin paper is enough.
• Coherent lasers do have a good manual with step by step instructions
• The birefringent filter has got strong reflections in the up direction. So always wear laser safety googles and never bend over the laser. There is usually a mark on the filter. Put it near 12 o'clock direction. Then optimize to the highest yellow fluorescence. (There are two positions for the same frequency but the 2nd produces more reflections/straight light pointing upwards, avoid it)
• Colleagues use a silicon diode (shielded with a long tube against straight light) and an oscilloscope to measure the fluorescence on the output coupler. The laser power meter is not sensitive enough. Then it is much easier to align the optics. The pump mirror is most crucial

Good luck. Nice hobbiest project

 

[TheTeslaWarrior]

This is a very advanced project. Just a few tips:

• You need a really clean, dark, temperature stable, vibration isolated environment. Fix your pump laser with a clamp on the desk. Put the dye pump on a vibration isolated block eg. polystyrene foam on the floor
• clean your optics with high purity acetone and methanol and lens paper. Be very carefull. Every scratch is irreparable. Just put a drop on the lens paper and pull it just once over optical elements, never tiwce. Every grain leaves scratches. Never push, gravity on the thin paper is enough.
• Coherent lasers do have a good manual with step by step instructions
• The birefringent filter has got strong reflections in the up direction. So always wear laser safety googles and never bend over the laser. There is usually a mark on the filter. Put it near 12 o'clock direction. Then optimize to the highest yellow fluorescence. (There are two positions for the same frequency but the 2nd produces more reflections/straight light pointing upwards, avoid it)
• Colleagues use a silicon diode (shielded with a long tube against straight light) and an oscilloscope to measure the fluorescence on the output coupler. The laser power meter is not sensitive enough. Then it is much easier to align the optics. The pump mirror is most crucial

Good luck. Nice hobbiest project

Thanks for the advice, i will try and make a mount that would allow for the laser to be clamped.

My coherent manual recommends using a piece of paper to find the bright spots.

 

[Analysis]

My coherent manual recommends using a piece of paper to find the bright spots.

A manual from the 1980's...
I recommend a blank visiting card to measure distances and align INSIDE the resonator. But for the output before you get laser threshold the reading is about 20 microwatts. That's hard to optimize with a blank card and pure eyes. A silicon photodiode is much more sensitive.

 

[LSRFAQ]

I use these at work. Can you borrow a stronger pump? Your looking for a few mW of output at best. With the BRF in place, your intracav losses will be quite high, if its out of tune. The consequences of removing the BRF means a serious tweek of the mirrors. It does allow the dye to lase across the whole gain curve, giving you a bit better chance.

50% H20, 50% MeOH with R6G.

Since ours are aligned and we have up to 15 watts average power of pulsed pump, dye strength is determined by putting in pure solvents, adjusting for a good jet shape, and adding drops of a superconcentrated dye solution till power peaks.

You'll need to match a prefered concentration and try to align, takes serious time and patience.

See attached, if you do not have this "Dumbell" cross section in the fluid just past the nozzle, which turns into the collapsing "flame" at its end, you will most likely see no lasing at all.

The vertical lines are the parallel part of the stream, and the nozzle is rotated so the jet is at Brewster's angle to the main lasing path.

The jet should be optically flat on the parallel parts.

You need to clamp down the pump and possibly upcollimate it.

If you get it on your skin, the dye goes straight to your brain, kidneys and liver. Wear gloves.

Let me know if you sell it, I'm the one you outbid.

Steve

 

[Seoul_lasers]

I'll second LSRFAQ... apparently some of the dyes for lasers are quite simular to those found in the production of OLEDs especially the blue dyes ~Quinone-imine derivative based dyes. We have a 3 layered (control) access facility for the production due to the toxicity of the "organic" dyes.

Wear a face sheild, full protection gear + gloves around the dye at all times. HIGHLY TOXIC stuff.