Lasers--what's new??

WaltH

Enlightened
Joined
Oct 30, 2001
Messages
536
Location
Florida, USA
Re: Lasers--what\'s new??

That's a good question. I've been holding off on purchasing a green laser for about a year now hoping the price would come down. As far as I can tell it has not.

Any cheap prices on quality 5mW continuous green lasers?
 

hank

Flashlight Enthusiast
Joined
Apr 12, 2001
Messages
1,561
Location
Berkeley CA
Re: Lasers--what\'s new??

I've lost track of the going price myself. The CPF "dealer" section has the thread titled "new led source" pointing to "superbrightleds.com" which has green lasers for $120. Is that good?

Their other prices sound good, but I haven' bought from them
 
D

**DONOTDELETE**

Guest
Re: Lasers--what\'s new??

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=1373459471

These are so shweet, I bought a second one. The brightness is -really- impressive, especially at clubs and bars, heh-heh.
Added feature not advertised: the circuit board in this pointer has a potentiometer plainly soldered to it, just begging to be twisted. I "tuned" mine by maximizing the current drawn at the batteries. Getting to the board can be a bit tricky, but I got mine off and on with minimal and next time preventable marring to the aperture side cap. After playing with mine, I know of two other people who rushed off and bought themselves green pointers.
 
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**DONOTDELETE**

Guest
Re: Lasers--what\'s new??

Hey,

Its been a while.

Heres a link to the cool laser faq:
Sams

Whats up with these 0.4% efficient lightcraft?

Would an optical-fuel dopant couple the 10.6um more efficiently to the air?

In 1998 they were supposedly balancing them at 5000 feet. What happened that 233 is something to celebrate?

It has been several years since I was "into the science" of lasers. What is the current state of the homebuilt?

As of 1998 people were making home-builts of the following types:
-Copper Vapor Lasers
-Nitrogen Gas Lasers
-CO2 Gas Lasers

For the most part the non-building public was pointing he-ne lasers at .. stuff. Enterprising non-building people (like Eugene & Jetson at nmt) would get very large lab-surplus lasers at auctions, and point it at .. um well circle K clerks, like cats chase glowing spots, sometimes, with lots of fresnel deflection.

My question is this:
What can an enterprising, intelligent, and fun-loving home-built laser builder build for less than a couple hundred bucks?

In my day *reminesces of stories of walking six miles up-hill in the snow each way to get to school, thanks grandpa* Ahem..

In my day, the state of the art was the COIL (chemical-oxygen-iodine laser), the giant boeng flying laser platform (H-F Chemical) and the free electron laser. Non-linear optics (like self-focusing, frequency doubling/halving crystals, and optical data storage were also hot.
What are the current "hot-rods" of laser technology today?

There were three methods to make the most of your beam: cavity dumping, q-switching, and modelocking. Are there any more?

Has anyone found a way to make a beam more temporally and spatially coherent? Do we have optical i-FELs yet?

Hey, this is cool.
lptrcmp1.gif


Thanks,

Mike Munroe
 

The_LED_Museum

*Retired*
Joined
Aug 12, 2000
Messages
19,414
Location
Federal Way WA. USA
Re: Lasers--what\'s new??

All I can think of right off the top is that blue and violet directly-injected laser diodes are now being manufactured. No extra optics (beyond a simple collimating lens like a red pointer uses), no vanadate, no KTP, no pump diode, no nothing. Could theoretically be driven directly using only a resistor; but at $3,000.00 a pop for blue and $1,000.00 a pop for violet, you'll probably want to use a feedback regulated driver.
blush.gif


Directly injected green, blue-green and blue lasers based on zinc selenide are being toyed with, but they have enough trouble making a good LED out of that sh*t that the laser is probably still a ways off.

Yellow, amber, and orange directly-injected diode lasers based on gallium nitride and related compounds *could* be possible, but I'm not aware of any significant research and I highly doubt anything like that will ever come to fruition. If anybody ever manages to create an orange or yellow diode laser, it will probably use compounds composed of such elements as indium, gallium, phosphorous, silicon, and arsenic.
 

The_LED_Museum

*Retired*
Joined
Aug 12, 2000
Messages
19,414
Location
Federal Way WA. USA
Re: Lasers--what\'s new??

Regarding the dual-beam green... it's either gone multimode on you, or the pump diode has developed a dark line defect. I'm strongly leaning towards multimode - TEM01 to be specific. If it's brighter than the other, and shoots as far or father, then keep it.
 

WaltH

Enlightened
Joined
Oct 30, 2001
Messages
536
Location
Florida, USA
Re: Lasers--what\'s new??

Just received my BTG-2 from Z-bolt. MUCH better than my red laser pointer. I actually got 2 of them. One has a nice tight beam, and the other seems to split into 2 beams very close together. The one with the split appears much brighter. But I wonder if it will lack distance. Should I send it back or keep it. I've heard stories of green lasers getting dropped and actually being brighter afterwards.
 
D

**DONOTDELETE**

Guest
Re: Lasers--what\'s new??

Someone was asking about the tuning of the z-bolt 532 lasers. Here's the method:

As long as its the same pointer, this will work.. The pointer I got is the one from z-bolt and the warning sticker refers to Lightvision Technologies Co.
The hardest part by far is getting that endcap off. I wrapped the cap with a rubberband for grip and protection and grabbed it with a pair of pliers. While pulling the cap away from the main body and gently twisting back and forth at 5 degrees or less the cap can be worked off.
Once the cap is off, the module and board are held into the shaft by the button only. The button visible outside the pointer (brass) has a bit of gummy adhesive on its backside to hold it to the real button on the circuit board. Carefully slide the board/module from the shaft, making sure to keep an eye on the gummy brass button. The plastic retainer bracket is easy to reposition later so don't worry about that.
When the board and module are free, the potentiometer will be plainly visible in front of the button on the board. I hooked it up to the ol' power supply and replicated battery voltage. Turning the pot too far makes the laser get dim again so some tuning is neccessary. Its really hard to tune something that bright by eye so I hooked the PS to the ol' multimeter and monitored the current draw. I tuned the pot to the highest current.
Reassembly is loads easier than disassembly; just press together. Watch that brass button!
When performed this, I got careless with the pliers and put some scrapes into the endcap. Next time, that won't happen. I just got a little 'project excitement'.
Anyway, I have done this and its really not difficult. Email me any questions or comments.

brendan
 
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