"First Look" at The 500mW Mitsubishi ML501P73 635nm/638nm diode is in.!

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in



I gotta get me one of those

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

@lazeerer

I suspect the drop off you see at 1.8A is due to Temp.

You might want to take a look at a video I made when testing a 300mW version.

http://www.youtube.com/watch?v=jVCoQK8YAec&list=UUov8oqObBY2dejJJx1AJhMg&feature=plcp]MVI 1262 – YouTube

I took the 300mW version to around 1W but of course chilled, all this usefully means is the bond wires could handle the current. I concluded it was quite safe to run the 300mW version to 755mW at 25C so I expect the 500mW to be fine to run around 1W also at 25c, more is just pointless.

You can also buy simple digital thermometers on ebay for peanuts, while they aren’t so accurate they are well worth it when doing these tests as they can show you what the power meters and PSU can’t.

Here is one that would fit good inside your block.
http://www.ebay.com/itm/LCD-Digital...pt=LH_DefaultDomain_0&hash=item3f115a9b3e]LCD Digital Fridge Freezer Thermometer Temperature | eBay

One final point, using that lens I think you are not getting very accurate results, use something like a glass G2 for the testing and you'll see an instant power difference. That lens could have losses as much as 25%

I am also looking for a load of 500mW versions, so if anyone starts a GB please let me know.

Cheers

A very busy Andy

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

DTR said:

Looks good. Yea after I posted I saw when looking at your photo next to mine how much of a voltage difference they were running @ around 1.5A and knew they are obviously different beasts.

Do you have a 300mW that you can do a shot of them side by side on a wall at distance. I would be interested to see what differences their output gives.:beer:

Click to expand...

I sure do Just look at the Sig. I will compare the 2 at your request.:beer:

andyf97 said:

@lazeerer

I suspect the drop off you see at 1.8A is due to Temp.

You might want to take a look at a video I made when testing a 300mW version.

MVI]MVI 1262 - YouTube 1262 – YouTube

I took the 300mW version to around 1W but of course chilled, all this usefully means is the bond wires could handle the current. I concluded it was quite safe to run the 300mW version to 755mW at 25C so I expect the 500mW to be fine to run around 1W also at 25c, more is just pointless.

You can also buy simple digital thermometers on ebay for peanuts, while they aren’t so accurate they are well worth it when doing these tests as they can show you what the power meters and PSU can’t.

Here is one that would fit good inside your block.
LCD]LCD Digital Fridge Freezer Thermometer Temperature | eBay Digital Fridge Freezer Thermometer Temperature | eBay

One final point, using that lens I think you are not getting very accurate results, use something like a glass G2 for the testing and you'll see an instant power difference. That lens could have losses as much as 25%

I am also looking for a load of 500mW versions, so if anyone starts a GB please let me know.

Cheers

A very busy Andy

Click to expand...

Thanks for the Info.

However at 1.8A IT dims out Like a 445nm diode when going to IIRC 2.1A. Turning the currant back alittle lets it laze again. I dont know the actually name for this if there is even one but i know its not due to heat. It falls out drastically if You leave it in that stage for to long it will end up burning out the diode.

If you look at my Sig you can see i have a "300mW" Mitsubishi diode running at a peak of 900mW+. However with the 300mW diodes they quickly drop in power. These 500mW Dont just like the video showed above. THey are pretty stable. Even at 1.7A its the same thing. a very slow drop and very stable. at 1.8A it just dims.

Here is an Example of DTR pushing the 445nm diode to its MAX and it does the same dimming thing.



You Can clearly see it dim out then come back when he turns the currant back.

^^^THis is Exactly what it does. In fact Most diodes do this. IF the do this means that this is there absolute MAX. For Example If I was testing this diode and at 1.8A something failed then most likely it would be the bonding wire and this means that the Die can take more but the wire cant in short words.

Trust me, its not due to heat. I know this 100%. THese 500mW diodes are NOT like the 300mW. Around ~1.8A is there MAX and I would not push it pst 1.5A.



The Lens i am using is a more common lenses used here. It gives the best "dot". Like i said in the OP i will be testing with the G1 and the G2 aswell as i have both those lenses. so stay tunned. 4am here.

If you are not Using Corrective optics then using the G1/G2 lens in a pointer is really not practical as the beam is 4 inch wide. LOL

SO that is why i tested with this lens. Plus when a member tested the 300mW diode on LPF he used an Aixiz Glass which again gives a better "dot" because it clips the ends off.

If your looking for nothing but power and going to be using corrective optics then sure go with the G1/G2 but not practical in pointer for this particular diode alone.

I think ~1W with a G1 lens on it will be fine and is what iam going to be running mine at or ~800mW with an Aixiz Glass or Acrylic lens. However this is what i plain on running mine at. Until we have more testing iam not going to say it will be fine.

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Beautiful!

I can't wait for the Beam comparison!

Good job man! Thanks for doing this! :beer:

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Regarding everyone's questions about beamspecs - yes, this should have exactly the same specs. The datasheet says that the slow axis divergence is 7.5 and the fast axis divergence is 35, the exact same as it was for the 300mW diodes. So the problem still remains here.

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Wolfman29 said:

Regarding everyone's questions about beamspecs - yes, this should have exactly the same specs. The datasheet says that the slow axis divergence is 7.5 and the fast axis divergence is 35, the exact same as it was for the 300mW diodes. So the problem still remains here.

Click to expand...

The emitter size could be larger though, making the beam even worse.

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Wouldn't that be accounted for in the divergence given in the datasheet? I mean, they measure the divergence of the raw output, no?

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

rhd said:

The emitter size could be larger though, making the beam even worse.

Click to expand...

http://nooooooooooooooo.com/

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Wolfman29 said:

Regarding everyone's questions about beamspecs - yes, this should have exactly the same specs. The datasheet says that the slow axis divergence is 7.5 and the fast axis divergence is 35, the exact same as it was for the 300mW diodes. So the problem still remains here.

Click to expand...

I don't think so, but I could be wrong.

Divergence is an angle, which doesn't tell you anything about the emitter size.

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Hmm. I thought emitter size is what gave a diode a certain divergence.

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Wolfman29 said:

Hmm. I thought emitter size is what gave a diode a certain divergence.

Click to expand...

I pretty sure that the emitter size has an impact on beam quality that either isn't, or isn't entirely, captured by divergence measurements alone.

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Hmm. Well. I guess we'll have to see when someone puts one of these in a handheld next to a 300mW, eh?

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Wolfman29 said:

Hmm. Well. I guess we'll have to see when someone puts one of these in a handheld next to a 300mW, eh?

Click to expand...

Im getting there.


THe Emitter on the 500mW ones appears larger.

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

I just saw, you are using the Heatsink from http://laserpointerforums.com/f52/2...f-009-mohrenberg-heatsink-tutorial-59251.html <this.

What happened?

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

eytyxhs said:

I just saw, you are using the Heatsink from http://laserpointerforums.com/f52/2...f-009-mohrenberg-heatsink-tutorial-59251.html <this.

What happened?

Click to expand...

Nothing. Its the biggest heat sink i have so i just unscrewed the set screw and slid out the module of the build to use the heatsink temporally.

You dont see the components anymore on the back because if you read later on in that whole thread you can see that i switch to a more efficient driver then the LM350 that i had original built it with.

Iam using the X Drive Now and its Heatsinked to the Pill.

Re: The 500mW Mitsubishi ML501P73 635nm/638nm diode is in

Fascinating stuff, thanks for sharing! :wave: