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- Aug 25, 2010
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Today, we gather to give thanks to the Lord our sheppard, for the gift that was our beloved friend, blue laser diode...
Sad but true, I was putting some final touches on the casing and the heat distribution system for my blue 1.25 watt laser build, with the batteries in the damned thing, and I slipped somehow and shorted just the right spot and blew the diode:
WAHHHHHHHHHHHH!!! :cryyy:
I knew I was begging for it but I thought I could slip it together without having to remove the batteries, which fit in the holder really tight, but alas I guess not. For what it's worth in terms of info for the group, this laser diode came into my hands about two months ago, and saw several changes in driver design and output power before this accident killed it. It began life in one of my small plastic cased pocket designs, operating at about 300 milliwatt. From there, I upgraded the driver board a couple of times, and ran the diode at increasingly higher powers. First, I made the 500mw mark, then 600, then 800, then up over a watt. Eventually I came to understand enough about the system to know what was holding it back from running yet higher, and I made the changes happen and ended up with a watt and a quarter, which is where I decided to let it stay. Running such high power quickly caused issues with heat dissipation, so I engineered an aluminum casing for it and gave it a largish heatsink for the diode housing. I ran it again and again at a full 1.25 watt or higher (I don't have an LPM so I am guessing based on the curves we've seen so far, with the input current at about 1.25A), gave it all kinds of burn tests and runtime tests, and was very impressed with it overall. Today, I was working on finishing up some of the details of the casing, and also was completing the heat transfer tab to channel heat from the current regulator to the casing, and I apparently bumped a sensitive spot and made just the right short. The diode emitted a brief and bright blue flash, and no more. I removed the diode, tested the circuit, tested the diode itself, and found that it was completely opened.
I'm already hot on the trail of a new diode, which hopefully won't take long to get here. Till then, I'll be focusing on adding the final touches to the casing and driver circuit (fan cooling, a modulation input jack and a safety killswitch), and then when the diode arrives, it will only take me a few mins to mount it and it'll be all done.
All I can say is next time, NO BATTERIES (when will I ever act like I know how risky this is???) and praise God these things don't cost hundreds each!
Sad but true, I was putting some final touches on the casing and the heat distribution system for my blue 1.25 watt laser build, with the batteries in the damned thing, and I slipped somehow and shorted just the right spot and blew the diode:
WAHHHHHHHHHHHH!!! :cryyy:
I knew I was begging for it but I thought I could slip it together without having to remove the batteries, which fit in the holder really tight, but alas I guess not. For what it's worth in terms of info for the group, this laser diode came into my hands about two months ago, and saw several changes in driver design and output power before this accident killed it. It began life in one of my small plastic cased pocket designs, operating at about 300 milliwatt. From there, I upgraded the driver board a couple of times, and ran the diode at increasingly higher powers. First, I made the 500mw mark, then 600, then 800, then up over a watt. Eventually I came to understand enough about the system to know what was holding it back from running yet higher, and I made the changes happen and ended up with a watt and a quarter, which is where I decided to let it stay. Running such high power quickly caused issues with heat dissipation, so I engineered an aluminum casing for it and gave it a largish heatsink for the diode housing. I ran it again and again at a full 1.25 watt or higher (I don't have an LPM so I am guessing based on the curves we've seen so far, with the input current at about 1.25A), gave it all kinds of burn tests and runtime tests, and was very impressed with it overall. Today, I was working on finishing up some of the details of the casing, and also was completing the heat transfer tab to channel heat from the current regulator to the casing, and I apparently bumped a sensitive spot and made just the right short. The diode emitted a brief and bright blue flash, and no more. I removed the diode, tested the circuit, tested the diode itself, and found that it was completely opened.
I'm already hot on the trail of a new diode, which hopefully won't take long to get here. Till then, I'll be focusing on adding the final touches to the casing and driver circuit (fan cooling, a modulation input jack and a safety killswitch), and then when the diode arrives, it will only take me a few mins to mount it and it'll be all done.
All I can say is next time, NO BATTERIES (when will I ever act like I know how risky this is???) and praise God these things don't cost hundreds each!
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