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

Buy Site Supporter Role (remove some ads) | LPF Donations

Links below open in new window

FrozenGate by Avery

PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please sub

Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

There are at least four versions of the 5.6mm 445's that we know of maybe even more and two versions of the 9mm 445's not counting the 3.5W diode. I am sure they came out in succession as they advanced in getting more power out of them with newer designs we just did not have access to them like we did with the 445nm diodes since they were in projectors that we know of.
 





Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

DTR said:
There are at least four versions of the 5.6mm 445's that we know of maybe even more and two versions of the 9mm 445's not counting the 3.5W diode. I am sure they came out in succession as they advanced in getting more power out of them with newer designs we just did not have access to them like we did with the 445nm diodes since they were in projectors that we know of.
Click to expand...

Very true, I didn't think about that- isn't there a 1.2W rated 9mm 445 out there?
 
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Ebay seller uschen_pvle0ilx7: 1W-NDG7475T-520nm-1000mW-9mm-green-high-power-laser-diode-laser-module $250 USD

http://www.ebay.com/itm/NICHIA-1W-N...-power-laser-diode-laser-module-/141614715882

He responded he will give me proof, but didn't send anything yet. I asked him to join the forum and come to this thread. I'm wondering how he can sell so much lower than DTR who has always had very good prices. I've always preferred buying from DTR because he has good prices, a great reputation for being honest and ships extremely fast, seems like I get what I order in two to three days every time which is quick to get something to Alaska, but if this is the real deal and his prices are that much lower for these diodes, I will order from him in Taiwan. I'd still buy from DTR for his other offerings which are great, just these greenies are so expensive I haven't been able to find ones at this power level I can afford until now, if legit.

DTR greenies: https://sites.google.com/site/dtrlpf/home/diodes/ndg-1w-520nm Did DTR just drop his price for these at his google shop? ? Now 335, I thought they were 370 yesterday. His ebay prices for them are still the same.
 
Last edited:
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Alaskan said:
1W-NDG7475T-520nm-1000mW-9mm-green-high-power-laser-diode-laser-module $250 USD

Nichia 1W NDG7475T 520nm 1000mW 9mm Green High Power Laser Diode Laser Module | eBay

He responded he will give me proof, but didn't send anything yet. I asked him to join the forum and come to this thread. I'm wondering how he can sell so much lower than DTR who has always had very good prices.
Click to expand...

They are trying to compete with the scads of other chinese sellers- even if it means only making a few bucks per diode.
 
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

If you can't make 10 percent or more on your investment, hardly worth doing business.
 
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

The thing with DTR's diodes is that you know you'll be getting a bona fide 1000mW NDG7475T laser for your $335, not some NDG700 passed off as a NDG7475T. That said, the price of the "NDG7475T" on some of those ebay listings is the same as the NDG700 on DTR's so there's really no risk as long as you're satisfied with potentially receiving some 700mW laser instead. DTR's shipping is really quick too.
 
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

I agree, I asked this ebay seller to show me the power curves and current, he said sure, but didn't send them.
 
Last edited:
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

I'm wondering if something like this could be used to make a variable output laser simply by reducing the size of the iris to a very small percentage of the beam size?

Camera Laser One Aperture Variable Iris Diaphragm Manual Aperture Zoom 0 11 8mm | eBay

Of course, this is for lower power laser pointers, put it in front of something more than 100mw and I'm not sure how well it will work for that.
 
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

No. The beam will melt/damage the iris. Even for low power pointers, some light would be reflected back into the enclosure and come out at odd directions, causing the aperture to glow like an LED unnecessarily. The edges of the material will also cause diffraction. https://en.wikipedia.org/wiki/Diffraction#Single-slit_diffraction

You'd have better luck rotating a polarizing filter in front of the beam to vary the power, or just varying the input current to the laser diode.
 
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

He finally sent me a photo showing a 520nm diode under test:

_12_zpsg6rie1iw.jpg


760 mA @ 8.4 VDC for 500mw measured, although the diode is far too close to the LPM sensor which can cause higher than normal readings, in my opinion the sensor should be at least 15 cm/6 inches away from the laser output.

The seller didn't send me a photo showing the diode being directly driven with a lab power supply (look closely, a driver in-line) so I can know the exact current and voltage going into the diode but even with a driver, is the amount of current shown at 760 mA normal for 500mw output with 8.4 VDC going into a driver? That's close to 6.4 watts being consumed by the driver and diode.

If directly supplying the diode at its specified max ratings of 4.6 VDC and 1.6 amps of current (current limiting built into the power supply) that's close to 7.3 watts consumed by the diode. There could be an amount of explainable difference, depending upon the efficiency of the diode, but with these figures, it is going the wrong direction at close to 1 watt less. The driver should consume more power, not less, but I don't know if the 1.6 amps max at 4.6 VDC shown on the specs are for exactly 500mw output, so from all of this and my limited knowledge regarding the possible differences of efficiency between diodes, I'm still not sure if this is legit.

e6d8a836-59e9-4425-af55-f427170892ab_zpst0pk3pqr.jpg
 
Last edited:
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Alaskan said:
He finally sent me a photo showing a 520nm diode under test:
760 mA @ 8.4 VDC for 500mw measured, although the diode is far too close to the LPM sensor which can cause higher than normal readings, in my opinion the sensor should be at least 15 cm/6 inches away from the laser output.
Click to expand...

Yea that is not all that helpful. One there is a driver in there. it is not being direct driven so no way to know for sure the current to the diode if it is a buck driver. Also the 700mW and 1W diodes are near Identical in the power curve till you get past 1.8A. @ 2A you can see the 700mW fold back where the 1W keeps climbing.:beer:
 
Alaskan said:
He finally sent me a photo showing a 520nm diode under test:

http://i853.photobucket.com/albums/ab95/LaserProject/_12_zpsg6rie1iw.jpg

760 mA @ 8.4 VDC for 500mw measured, although the diode is far too close to the LPM sensor which can cause higher than normal readings, in my opinion the sensor should be at least 15 cm/6 inches away from the laser output.

The seller didn't send me a photo showing the diode being directly driven with a lab power supply (look closely, a driver in-line) so I can know the exact current and voltage going into the diode but even with a driver, is the amount of current shown at 760 mA normal for 500mw output with 8.4 VDC going into a driver? That's close to 6.4 watts being consumed by the driver and diode.

If directly supplying the diode at its specified max ratings of 4.6 VDC and 1.6 amps of current (current limiting built into the power supply) that's close to 7.3 watts consumed by the diode. There could be an amount of explainable difference, depending upon the efficiency of the diode, but with these figures, it is going the wrong direction at close to 1 watt less. The driver should consume more power, not less, but I don't know if the 1.6 amps max at 4.6 VDC shown on the specs are for exactly 500mw output, so from all of this and my limited knowledge regarding the possible differences of efficiency between diodes, I'm still not sure if this is legit.

http://i853.photobucket.com/albums/ab95/LaserProject/e6d8a836-59e9-4425-af55-f427170892ab_zpst0pk3pqr.jpg
Click to expand...


tl;dr

Buy your diodes from DTR ;)
 
Last edited:
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Lol^ :crackup:
 
Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

noobphaser215 said:
2.5w 9mm 638..???? has anyone ever had their hands on this bad boy?
Mitsubishi G84 638nm 2 5W 2500mW Laser Diode TO5 9mm Orange Red Laser LD Cut Pin | eBay
Click to expand...

There was a lengthy thread about it a few months ago but no one ever got one. There was a Mitsubishi 9mm 638nm that puts out twin beams, I don't know if this is that one or if there is another one that has a single beam.

Alan
 
You must log in or register to reply here.





Back
Top