Anyone knows what kind of crystal is this?

[VaThInK]

I saw this on eBay and I'm wondering what can it be used for.

Link: eBay.

Any ideas?

[marconi]

I believe they are used in the 1500nm area..
Other than that I dont remember what good they are.

[Laser Ben]

It's part of a modulator for 1310/1550nm switching.

[VaThInK]

Oh well, it's out of my interest then . I thought when the seller mentioned YVO4, the other crystal might be KTP . Thanks guys.

[eyceage]

I believe they are used in signal demultiplexing.

aerodynamics2006 was buying them from laserhobbyist for $15 and relisting them as KTP/vanadate modules for like $300 a few months ago.

[VaThInK]

Hum, another misconduct from aerodynamics2006 as if he hasn't got bad enough reputation already.

Back then, I bought a DPSS laser housing from him that he claims able to withstand 7W of c-mount pump diodes no problem. As it turned out, the housing only accept 1W TO-5 diodes max (it is such a small housing). The surface of the crystals only measures at 1mm^2 which he claimed to be 2.1mm^2. What's worse is the fact that the TEC unit is broken into 2 when I received it and he promised me that he will send a replacement TEC unit made for NASA (yeah right!), which I haven't received yet despite I've been waiting for more than 3 months. Such a dishonest seller practicing misadvertisements. He's good at lying though . He told me that he's an engineer working at Australia's aerospace division. I bet he's lying about that as well. Stay away from him guys. He's just full of it.

Rant(off);

[Laser Ben]

I sent him a message about his diodes. Her got back to me saying he buys all of his diodes new from coherent. I know he is lying because there are screw marks on the mounting tabs.

[VaThInK]

I sent him a message about his diodes. Her got back to me saying he buys all of his diodes new from coherent. I know he is lying because there are screw marks on the mounting tabs.

I don't think Coherent will let him buy in a small quantity as he only auction the diodes rarely. I reckon he's just a broker by the look of it. Trying to get some gain from someone else misfortune. He also told me that the DPSS housing is brand new and tested. How can it be brand new when it's missing 2 bolts, 2 of the remaining bolts have cosmetic damage, TEC unit broken and the cable indicates that it's been cut off (only about 10cm long). It's a recycled unit for sure. Over speced too.

[eyceage]

He even had the guts to reuse the pics from the original auction when he relisted it.

What a tool.