SHARP's Newest Red LD

[phenol]

here's the link:
http://www.sharp.co.jp/corporate/news/071219-a-2.html
basic specs:
max cw output: 135mW
pulsed output /pw 35ns, duty cycle 35%/: 400mW
threshold current: 75mA
op. current for Po=120mW: 200mA
peak wavelength: 660nm
divergence || to junction: 10 degrees
divergnce perpendicular to junction: 16 degrees
op temp (cw): -10 ~+70C
op temp (pulsed): -10 ~+80C
frame-type package.

Start of mass production is planned for this month.
It is interesting to see how low the specs are compared to how hard we overdrive them. I dont think that open cans have much better specs than this...

 

[IgorT]

It is interesting to see how low the specs are compared to how hard we overdrive them. I dont think that open cans have much better specs than this...

That always surprises me as well. I just measured one of my 16x LDs at 185mW! And it's been running like that for half a year now.

The CW output always seems so low in the datasheets. We are running these CW at close to pulsed power. Sometimes even more.


Because of that, I wouldn't be surprised, if the open cans actually had lower specs than the one you linked. Do you perhaps know what recording speed it is meant for?

 

[phenol]

there's no mention of recording speed in any of the documents i encountered, but i do know that its 350-mW predecessor /GH16P35A8C/ is intended for 16x dual layer burning. current DL speeds in 20x burners are 10x. I got a nec-optiarc drive with 12x DL speed and found a flat diode that had the same appearance as those sharp ones, probably the 350mW version. I opened its plastic cover and measured its chip length - 1.80mm as opposed to 2.15mm of 'long' open cans. havent tested it yet, as it wont fit in any housing i can think of.
another thing - CW specs are low maybe due to the wide temp range these must have. if we drove them CW at pulsed power levels at 70C, they wouldnt have survived as long as they have.

 

[GooeyGus]

I'm guessing the CW rating is so low because they have to build SO many of these things, that its more of a quality control issue. Even if 70% are capable of far more than the rating, they still have to give it the lower rating to ensure that 100% of them will function as long as they say they will.

 

[IgorT]

I got a nec-optiarc drive with 12x DL speed and found a flat diode that had the same appearance as those sharp ones, probably the 350mW version. I opened its plastic cover and measured its chip length - 1.80mm as opposed to 2.15mm of 'long' open cans. havent tested it yet, as it wont fit in any housing i can think of.

Wait.. This is gonna be a flat chip type, or a can?

I am currently making a laser out of one of these flat diodes, for a friend. Since my first can ever didn't want to go out of the heatsink, i had to improvise, and with some patience, it is possible to put a collimator in front of it, and even make it adjustable.

What model was this NEC Optiarc, that has the flat diode?

another thing - CW specs are low maybe due to the wide temp range these must have. if we drove them CW at pulsed power levels at 70C, they wouldnt have survived as long as they have.

That's a very good probability..

I'm guessing the CW rating is so low because they have to build SO many of these things, that its more of a quality control issue. Even if 70% are capable of far more than the rating, they still have to give it the lower rating to ensure that 100% of them will function as long as they say they will.

That's also one of the factors.

I managed to kill two diodes, that were identical to the one, that just measured 185mW, and at lower currents. But i always had a feeling, this one is a freak.

 

[phenol]

flat frame-type. very fragile. heres a link describing it and the drive i took it from:
http://www.laserpointerforums.com/forums/YaBB.pl?num=1207306830/0#0

 

[IgorT]

flat frame-type. very fragile. heres a link describing it and the drive i took it from:
http://www.laserpointerforums.com/forums/YaBB.pl?num=1207306830/0#0

I meant the new diode from Sharp. Will it be the same type?

 

[phenol]

yes
package dimensions will be: 5.1×1.8×8.8 mm
sux