Taking apart the WL Core...

[hwang21]

So I had a WL core lying around (of many ) so I randomly decided to take it apart... turns out, the 5mW (LPM'ed) green laser uses a 200mW IR diode, LPM peaks at 216mW. There is an IR filter placed right after the KTP unit, after which there is a beam splitter that feeds the photodiode that ensures constant output. There are also a couple collimating lenses here and there, and everything inside is all brass. Lots of fun taking it apart until I shattered the KTP by accident... oops lol but yeah, quite a bit of fun. I wasn't expecting such a powerful IR diode, I was thinking 50-100mW at most. Interestingly, turning the pot doesn't really change the output much... a quarter turn in either direction decreased the overall IR output by ~10mW. The original factory setting was very close to the peak output of the module. Interesting stuff... a very neat construction, the internal build quality is pretty good aside from an odd placement of the on/off switch on the board (right next to the - end spring). The diode+heatsink also heats up pretty quickly by itself... Sooo now I have an IR diode+driver, a bunch of crap, and no KTP... any ideas anyone?

EDIT: Pics uploaded! There's also a light that lights up on the board when the unit is activated... but the Core has no holes in it's host except for the button hole and the aperture... pic 1 shows the module+driver (and the photodiode sticking out), 2 shows the KTP host, 3 shows the collimating lens, 4 shows the entire laser broken down, 5 is a zoom in of most of the components, 6 is a detailed view of the optics in the front of the laser, 7 shows the light on the board, and 8 shows the LPM

 

[danefex]

You cant just tell us this & not pos..... did you take any pics to share?? I have a WL core too, one of my 1st 5mw greenies from yrs ago that still runs as good as they day I got it. Best pet toy laser ever, I'd love to see what the inside of this thing looks like though without taking it apart. Please share the procedure if you took any pics

:beer:

 

[norbyx]

Yeah pics would be great.

 

[hwang21]

Posting pics now... Any suggestions?

EDIT: More photos added

 

[Livinloud]

Could you place the diode any closer to the ophir?!?!? You could be getting a very false reading due to the heat coming off the diode beinf absorbed by the sensor

 

[hwang21]

Haha I know but I had to do that beacuse there is a very high focusing lens in the module so if I move it even a couple centimeters the dot would be bigger than the sensor's area... I messed around with the optics but I couldn't re-collimate just the IR beam so I gave up on that for the moment. And I've tried out the distance issue before, there doesn't seem to be much of a difference... a few mW's, if anything. The OPHIR seems pretty good at picking out heat and light, I have to place my hand on the heatsink for the readings to change at all. I've tried putting the warm diode next to the sensor (diode off) and the reading didn't change at all (still read 0.000)

 

[ARG]

You should move the laser back like 20-30cm. Putting it right into the sensor isn't good, the heat from your laser can throw off the readings.

 

[hwang21]

I need to figure out how to collimate the IR coming out of the diode... the focal point is less than 0.5mm from the end of the diode. Any ideas?

 

[Cyparagon]

turning the pot doesn't really change the output much

The feedback it's looking for is optical. Even if you had the assembly in place, it's been designed to read the green output. If you smashed the KTP, the feedback loop is gone, and the output shoots up to some pre-determined max setting.

the heat from your laser can throw off the readings.

And your fingers alone will put out >10mW.

the focal point is less than 0.5mm from the end of the diode. Any ideas?

No, it doesn't have a focal point at all. The beam starts at a few microns, but since it is so small it diverges rapidly.
Collimate it like you would any laser diode - with a convex lens.

 

[Smeerworst]

Nice!... thank you for sharing...

i love my core and Phoenix

 

[hwang21]

Cyparagon,

I'm guessing that would that need to be a flat on one side and convex on the other (Plano convex lens I think it's called?), not a double convex lens, correct?

Smeerworst,

Not a problem! Enjoy your (good) WL lasers!

 

[Cyparagon]

Either will work, but plano-convex is better. Meniscus or aspheric is better yet.

 

[hwang21]

Ok there's only two lenses in the laser unit, not enough to collimate the IR beam enough. Magnifying glass hunting time...

 

[Smeerworst]

How many cm or mm is the LED removed from the button.

Maybe i will drill a hole in it and put a piece of plastic in it, like the back transparant tip of a ballpointer pen (the clicky)

 

[Smeerworst]

Nevermind

I just went ahead and just did it, (just now from my last post) and while i was at it i polished it aswell ^^


I used the tip of a pen ''the clicky thing'' and cut it to the right size.
The top of it is nice and round without sticking out too much.
It lights up nicely green when the button is pressed.

Still needs a finishing polish, but for now i'm done and did it pritty quick

Here ya go...

Cheers, Sm..

 

[hwang21]

Very nice! Looks sweet :beer: