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ArcticMyst Security by Avery

is this one 445nm diode or I received wrong diode?

alx

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As you can see it on first picture, all tests has been done using supplementary heatsink over Aixiz nut. At less than 600mA and few seconds test, heat in this case will not be a critical factor! So... I think I own "new 445 aliens" diodes!

I already informed the seller that I received wrong model. Still waiting an answer!
 





alx

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You say that you have 7.5V and 250mA on the diode at the same time !? These diodes should have about 4V at 250mA. 7.5V without current limit would kill them.

My guess would be your lab source is the culprit. Maybe it just can't give more current.

No, 7.5V is at driver input, not at diode :)). On LM317, we have 4.3V (diode) + minim 2.2V voltage drop across driver, plus 0.5-0.7V voltage drop in wires plus dummy 1 Ohm resistor, so 7.5V is very conservative! Also, LM317 will transform surplus voltage in heat, so again, no problem if will be 8V or 9V instead... just more heat in driver! The same driver works very well with blue-ray diodes, red diodes (LPC-815) and IR diodes too ...
 
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daguin

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It looks like a SF-AW210 diode (violet; 6X; 170mA; $15). It has the short pins and the large square barcode that the SF-AW210 has.
It's even got the large "spot" under the negative pin in the barcode.
20898-feeler-sf-aw210-diode-closed-shell10.jpg

29700d1286041560-one-445nm-diode-i-received-wrong-diode-img_0427n.jpg


Here is the back of the 445nm diode. I know my skillz such, but you can see that the square barcode is different and smaller
445barcode.jpg


Here you can see the shorter case pin compared to the anode and cathode. Straight out of the projector the anode and cathode are even longer. I cut these off just below the solder blob
Notice that there is no solder on this part of the pins
445pins.jpg


Peace,
dave
 
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DrSid

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No, 7.5V is at driver input, not at diode :)). On LM317, we have 4.3V (diode) + minim 2.2V voltage drop across driver, plus 0.5-0.7V voltage drop in wires plus dummy 1 Ohm resistor, so 7.5V is very conservative! Also, LM317 will transform surplus voltage in heat, so again, no problem if will be 8V or 9V instead... just more heat in driver! The same driver works very well with blue-ray diodes, red diodes (LPC-815) and IR diodes too ...

OIC .. all right then !
 

alx

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It looks like a SF-AW210 diode (violet; 6X; 170mA; $15). It has the short pins and the large square barcode that the SF-AW210 has.

Yes indeed. I already told you in private that I know that in the past, you discovered the stamp on some 405nm blue-ray diodes! Now is clear, they shipped to me SF-AW210 instead Casio A140 diodes!

Here is the back of the 445nm diode. I know my skillz such, but you can see that the square barcode is different and smaller
445barcode.jpg


Here you can see the shorter case pin compared to the anode and cathode.

Again you are right! Not only the barcode, also the middle pin is shorter than other 2 pins. On my diodes all pins are the same size and all are shorter than the can!

Now, no doubt! They shipped to me 405nm diodes instead 445nm casio A140... The spot also confirm this theory: is not large flat square... is almost (flat) round ;-), like the one produced by BR diodes!

Regards,
Alx
 
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Oh: now i realized that scaling it (to match forum rules, no larger than 800x600), a lot of details has vanished. Dave, Patt, can you PM your private email address in order to sent photos at original resolution (4.2MB/picture). Using actual one you will not be able to zoom in and see details!

You don't need more than 800x600. Look at all that wasted space around that tiny diode in the middle of those photos. We don't need to see your bed spread in full 12MP detail! Just crop the damn photos to the object of interest: the diode.

Need free software to do it? Download Irfanview. Then just select the area that you want to crop to, go to Edit -> Crop selection, and then save it as a new file. You can even resize it after.
 

alx

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Chinese peoples ... probably someone "myopic" from their depot :)

happy-end story! after almost 3 months, Chinese seller concluded that it was a mistake and sent me in compensation a lot of red diodes and few powerful br diodes (bdr-s06j).

thanks to all posters in this thread

Regards,
Alx
 

midias

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Glad to hear you got things worked out those china companies can be a bear to work with.
 

Benm

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It seems fairly clear from the pics that these diodes are in fact 405 nm bluray ones, not casio 445 nm diodes.

Your measurements concur with this - the casio 445 nm diodes will not lase when fed with only 130 mA or so, their treshold is in the order of 200 mA. I think you have been scammed.
 
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I dont understand - if you can get it to make a beam just see what color it is

there is a difference between the 405 and 445 in color that you should be able to notice
 




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