Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

Pioneer 8X Blu-Ray-- BDR-203

Joined
May 14, 2008
Messages
468
Points
0
Excellent pictures, Dave!! Now we know what a .512mW 512mW BR beam looks like! Thank you! :D :D :D :D :D
 





Joined
Aug 25, 2007
Messages
2,007
Points
63
lordoflasers said:
Some one should invite Shuji Nakamura to this forum to see what we do with violet lasers. *I bet he could get some really awesome diodes.

BTW , *he was the first to discover violet lasers as diodes, and also blue LEDs.

Shuji pretty much knows.*I doubt he knows of the full scale of just how much power we are getting in how small of a device, like Dave's .5W in a handheld here, but I can show him some of these recent results next week.*He at least knows of several of the hobby lasers that I have personally, like small pocket pal PHR lasers at 100+ mW, and I have made several PHR lasers for use in his labs and other labs here for photoluminescence.

He was one of the original laser hobbyists though, he had a small violet handheld, looks a lot like jayrob's first pocketpal host actually, before anyone on here had started making those things. I have heard that one of his early, like mid to late 90s, talks about his original work on violet laser diodes was done using his actual experimental diode for his presentation pointer.*So imagine "In this talk, I will be discussing the first ever CW operation of a violet laser diode, and I will be using this violet laser diode for pointing during my presentation". Pretty badass, if true, but that's just what I've heard.

As far as getting laser diodes, the sources here on LPF are much cheaper than anything our labs can get through "official" channels.*Our research group is in competition with many of the companies making these things, so they generally don't just give us things.*We work with many of them in many ways, but they are competition at the same time.*I'm sure Shuji personally has a connection or 2 with these companies, but they're still competition.

You may be thinking of his time at Nichia as a place where he could get cool things, but remember he and Nichia didn't split up amicably.*There is quite the history between them, including lawsuits.
 
Last edited:
Joined
Nov 7, 2008
Messages
5,725
Points
0
Wow, pullbangdead.. You should consider yourself very fortunate to have the honor of studying (or at least consulting) with Dr. Nakamura. I'd give a pretty penny of my own just to be able to sit down and talk to him for an hour over lunch.. That man has singlehandedly altered the future in ways we can't even fully understand yet.. not to mention making the world a much greener place in the process through the invention and perfection of white-light LEDs..

Lucky you..
 
Joined
Nov 22, 2008
Messages
1,506
Points
48
Agreed, but it will only be when white LEDs replace these godawful flourescent "bulb substitutes" that the world really recognises what he has helped to achieve. Sadly, I don't think that we will be seeing them for the next few years, and by this time, so either his contributions will be shadowed by the person who makes it into a commercial opportunity, or (even worse) everyone will be using flourescent tubes!

As you might have guessed, I don't like flourescent bulbs very much - I can often see the flicker, and hate the colour warmth (or lack thereof!). If they ever phase out incandescents without nice warm LED replacements, is anyone else going to be stockpiling them, or is it just me? ;D

On topic, though, any news from the Class 4 monster of a laser?
 
Joined
Oct 26, 2007
Messages
5,438
Points
83
Speaking of CFL, you might want to check out those "warm" CFL bulbs. They are much better. Unfortunately, a lot of owners of buildings and houses use those cheap-ass CFL bulbs because, well, they're cheap. It will be nice when solid-state lighting is the norm though. It'll probably require those blue laser-driven LEDs for the required amount of light.
 
Joined
Aug 25, 2007
Messages
2,007
Points
63
ElektroFreak said:
Wow, pullbangdead.. You should consider yourself very fortunate to have the honor of studying (or at least consulting) with Dr. Nakamura. I'd give a pretty penny of my own just to be able to sit down and talk to him for an hour over lunch.. That man has singlehandedly altered the future in ways we can't even fully understand yet.. not to mention making the world a much greener place in the process through the invention and perfection of white-light LEDs..

Lucky you..

I am amazingly lucky in many ways. Just to clarify my background, I'm a Ph.D student at UCSB in Shuji's research group. Shuji is a really nice and cool guy actually. It takes a little bit to get past the accent, but it's not too bad really. I'm actually taking his class this coming quarter, which starts next Monday. It's an optoelectronic device processing class, and it is supposed to be very good.

So yes, very lucky to be here. I have made some of my own luck in getting to where I am, but have had a very large amount of luck that I had no control over go my way as well. For instance, I made my own luck in being a good enough student and doing the right things to get to come to UCSB for grad school in materials science, where Shuji is a professor. But it was completely blind luck that I was able to graduate last year and come to UCSB this year, when Shuji was taking on new students; instead of graduating this year and coming to UCSB next year, when Shuji is (reportedly) not taking on any new students.

So yes, I am lucky, and I don't think I'd trade where I'm at for anything else in the world. Very thankful for the opportunity, and never dreamed I'd actually be able to work with the people I'm working with until it was actually happening.

Work hard in school, kids. ;)
 
Joined
Dec 30, 2007
Messages
573
Points
0
Great beam shots Dave. I take it you don't have a smoke detector in the garage... ;D

It will indeed be interesting to see how long this beast can last. May it live long and phosphor. ::) (OK, that one stunk... LOL)

Cheers, CC
 
Joined
Nov 24, 2007
Messages
2,735
Points
0
pullbangdead said:
[quote author=ElektroFreak link=1236464366/240#246 date=1238008699]Wow, pullbangdead.. You should consider yourself very fortunate to have the honor of studying (or at least consulting) with Dr. Nakamura. I'd give a pretty penny of my own just to be able to sit down and talk to him for an hour over lunch.. That man has singlehandedly altered the future in ways we can't even fully understand yet.. not to mention making the world a much greener place in the process through the invention and perfection of white-light LEDs..

Lucky you..

I am amazingly lucky in many ways.  Just to clarify my background, I'm a Ph.D student at UCSB in Shuji's research group.  Shuji is a really nice and cool guy actually.  It takes a little bit to get past the accent, but it's not too bad really.  I'm actually taking his class this coming quarter, which starts next Monday.  It's an optoelectronic device processing class, and it is supposed to be very good.  

So yes, very lucky to be here.  I have made some of my own luck in getting to where I am, but have had a very large amount of luck that I had no control over go my way as well.  For instance, I made my own luck in being a good enough student and doing the right things to get to come to UCSB for grad school in materials science, where Shuji is a professor.  But it was completely blind luck that I was able to graduate last year and come to UCSB this year, when Shuji was taking on new students; instead of graduating this year and coming to UCSB next year, when Shuji is (reportedly) not taking on any new students.  

So yes, I am lucky, and I don't think I'd trade where I'm at for anything else in the world.  Very thankful for the opportunity, and never dreamed I'd actually be able to work with the people I'm working with until it was actually happening.  

Work hard in school, kids.  ;)[/quote]
Can you ask him if exposing the die of a 405nM diode is harmful to it?
 
Joined
Aug 25, 2007
Messages
2,007
Points
63
As far as LED lighting, there's still work to be done. Some companies are bringing products out right now, but it's not ready for prime-time in-home primary lighting.

There are several ideas out there for how to get color temperature up and get color reproduction index up. the "classic" white is a blue LED with a wide-band yellow phosphor, as I'm sure most of you know. But blue plus yellow doesn't necessarily reproduce color well. So people are trying to figure out how to get better color reproduction AND energy efficiency out of the while LEDs. You can use 3 LEDs in one case, a red, a green, and a blue. Another option is going to a single UV LED with 3 phosphors, a red phosphor, a green phosphor, and a blue phosphor, then a UV-blocking container. Or blue with red and green phosphors somehow. There are a lot of ideas floating around, it'll get there eventually with the efficiency and the color temperature/color reproduction suitable for indoor lighting.

I personally can't wait, those "ice cream cone" CFLs are ugly.
 
Joined
Jan 12, 2008
Messages
3,290
Points
83
I use LEDs at home. I gotta thank Shuji for the work on LED, I probably like 'em more than lasers.

As for CRI, you want as many wavelengths possible without any peaks, right? I find using RGB for lighting very poor.


Oh sorry for OT, this just happen to be relevant to my interests. [smiley=engel017.gif]
 
Joined
Aug 25, 2007
Messages
2,007
Points
63
Spyderz20x6 said:
Can you ask him if exposing the die of a 405nM diode is harmful to it?

I have previously asked a project scientist I work with about this (project scientists run all the projects, it's a big group, so there is a lot of delegation of the day-to-day research), and his response was that it was not clear. This particular scientists has been in laser diodes for decades, and was basically running the entire III-N laser diodes project for the group, so he knows his stuff. He basically said "maybe", but it really depends on how the device is processed. Air shouldn't be doing anything to the GaN/InGaN really, that stuff is amazingly tough.

His idea was that MAYBE air can mess with facet coatings, if there are any on the diode. Generally, laser diodes can often work with etched facets or cleaved facets to make the cavity mirrors. However, to make the diodes work better, it's fairly common to put coatings on the facets to increase the reflectivity. If therea re facet coatings, and those coatings are of materials that can be affected by humidity or air in general, then maybe those coatings could be breaking down. If the coatings break down, then the reflectivity could drop or just mess up the diode in general.

So, as unfulfilling as it is, it's a big "maybe". His answer was: if the window is already broken, de-can it. You have nothing to lose. If the can is ok and intact, don't risk it, since there's barely anything to gain anyway, and it may be a problem for facet coatings. But it shouldn't be doing anything to the GaN.
 
Joined
Nov 24, 2007
Messages
2,735
Points
0
FireMyLaser said:
I use LEDs at home. I gotta thank Shuji for the work on LED, I probably like 'em more than lasers.

As for CRI, you want as many wavelengths possible without any peaks, right? I find using RGB for lighting very poor.


Oh sorry for OT, this just happen to be relevant to my interests. [smiley=engel017.gif]
Get out.
 




Top