Laser Projector (Red, Green, Purple) "Laser 3D Party Light" from Spencer's

[DogP]

Cool... yep, lots of good information there!

BTW, another interesting development... it looks like someone posted a hack for the Transcend Wifi SD card: http://hackaday.com/2013/08/12/hacki...wifi-sd-cards/ . That'd certainly make loading new files to this projector more convenient... and with the noticable buffering period during drawing, that probably means that you can load files while the projector is running, and it'd handle it just fine (and even cooler, can probably generate files on the fly directly from the ARM running on the SD card).

I've got one of those cards on the way... I'll probably at least give it a try on this, though I have a few things that it'd be useful for... so I dunno where it'll end up living. I'll be sure to post how it works on this though.

It looks like one called PQI Air also does the same thing (that one has a Micro SD slot, rather than built-in flash): http://www.newegg.com/Product/Produc...82E16820141601 .

DogP

[DogP]

Hmm... the PQI Air arrived, and it doesn't seem to work on my projector. :-/ Using a Micro SD card with an adapter works, but when I use the PQI Air as the adapter with the same Micro SD card, it doesn't do anything. I'm not sure, but it's likely that the projector talks to the SD card in SPI mode, and it's very possible that the PQI Air doesn't support SPI. According to someone else's post, the Transcend one didn't seem to talk SPI either.

DogP

[DogP]

I had more fun with my Frankenstein projector... I was ordering some parts from DTR for another laser project, so I decided to pick up some of his cheap 3 element glass lenses ( https://sites.google.com/site/dtrlpf/home/glass-lenses ), and popped them into the projector today. It's definitely an improvement (cleaner dot, a lot less "splash"), though I'm not sure I'd recommend doing it, unless you've got the lasers out for another reason. The blue one went in pretty easily, since I had already adjusted the lens before, and it's in a position that you can adjust it without removing the housing. The red one was much more difficult. I had to remove the housing from the heatsink (too close to the dichro to safely get a screwdriver in), and after that, I still had to get the lens out. Once they adjust them at the factory, they put a bit of glue to hold them in place, which makes it tough to get out (once you break it free, the threads are still clogged with glue). The clogged threads made it a hassle to put the new lenses in as well. But, after it was all done, it looked good. Of course I had to align the lasers again.



Unfortunately, the lenses only fit the red and blue lasers... the hole for the lens on the green one is larger (the same size as the threads on the outside of the red/blue mounts). Not sure why they did that... though everything to do with the green laser mount seems really screwed up.

I saw DTRs 520nm direct diodes have come down in price a bit, so while I had the projector apart, I decided to look into what it'd take to make one of them work. I took a closer look at how the green laser is mounted, and it's really weird. They have that large heatsink, but the diode (5.6mm) is pressed into an aluminum piece on the back, which is screwed to that heatsink with just two screws (there are 4 holes, but only 2 screws used), and with hardly any surface area touching. There is also a brass piece on the front of that, with what I'm assuming is an IR filter glued to it... and when you unscrew that from the aluminum piece, there's something else under that (maybe another IR filter?). Below are some pics:











So basically, the large heatsink is just functioning as mount to hold the diode and lens at the right height and distance apart. It seems like it'll be pretty useless as a holder for one of the 3.8mm 520nm diodes though, unless you can thread a 3.8mm mount into the lens thread or onto the IR filter thread (neither of which would transfer the heat very well). I'll have to see if I can find another holder like the red and blue have, and get a 12mm mount for the 3.8mm diode... or maybe rig something that screws to the holes on the back of the heatsink. I think that's going to the back burner for a bit.

DogP

[DogP]

So I think I found what the green laser mount is based off of: http://www.ebay.com/itm/13mm-Inner-D...item1c277a61b7 . It should be a drop-in replacement of the green heatsink... it's kinda weird that it's got a 13mm hole, when most modules are 12mm, but it'd probably work fine at the low power that I run my lasers at (maybe I'd use a bit of thermal goop or adhesive to transfer the heat better).

And I was also looking at some green laser stuff, and I think I get what those pieces are (from the wikipedia diagram: http://upload.wikimedia.org/wikipedi...s-diagrams.jpg ). The first lens on the aluminum piece is the pump focusing lens... then the brass piece has the crystal (underneath) and the expanding lens (on the outside), and of course the collimating lens is on the other side of the heatsink. So, there's probably no IR filter on this (not surprising).

On another note, I seem to have destroyed my red laser diode (very dim output). After I replaced the lenses and got everything realigned, I figured I'd tweak the power to get everything perfectly balanced. Immediately when I moved the red adjustment pot, the red went away... DOH! So the pot is probably dirty or something, and caused a surge from the large quick adjustment.

Oh well, at least it was just the red diode... I've got a cheap replacement on the way (it's just annoying that I got everything back to normal and tried making a very minor adjustment and now I've got more work to do).

DogP

[VibrationsOfDoom]

Hi, I have recently started down the path of lasers... and as a starter one i have a very similar unit to the one described in this thread (http://www.chinavasion.com/china/who...aser_Projector)

But... It's a pain to get showing files except the ones that was included... It only shows 5 of the files in this post. it shows:

DOG-P.ild
500pts.ild
XY-MATCH.ild
103TEST.ild
150OPTIMIZE.ild

The others it just skips, I have also tried loads of other files from here but most if not all don't work i my projector.

From what I figured by looking at the included files it only shows ilda 0 files...(as the unit in this thread) but even when I make a file with bmp2ild_v2 and then LaserBoy to switch to version 0 (3d frame) i only managed to make it show a tiny red dot once!

Anyone have an idea on what format it can show? or what limitation I have to follow to make it show my own files?

(also if someone ells have the same unit, it wont show files from katalogs that you make even if you put a correct .prg file, don't get stuck there like i did for a week)

Best regards.

/Bo

Just so you know, I recently checked out this link, and the unit you described is no longer available... However, the website shows a new and improved version, which is now white colored, and featured here:

http://www.chinavasion.com/china/who..._SD_Card_ILDA/

Not sure much about this unit, tho... Dunno if anyone checked it out (sorry if I didn't see this mentioned in another post)...

Still enjoying the Spencer laser, even with the burned out violet laser...

[DogP]

I got my red diode replaced... as usual, nothing's easy. The housing that the blue diode was in had the diode held in by a threaded brass piece. The red diode holder looked similar (a little bit longer IIRC), but when I took it apart, I saw that the diode was actually pressed into the holder. And the cheap replacement diode I got was mounted in a housing (brass housing with a driver circuit and some epoxy), so I had to safely remove it from there. Of course I don't have a diode press, and I'm too impatient to wait for one... but somehow I pulled it off, and it worked.

It looks REALLY good now with the nice blue and red lasers and optics. When the green lights up, there's a lot of splash, but that's what crappy optics do I guess. Hopefully I'll replace that soon with a direct diode and better optics. Then I just need to find some time to finally finish my sound card DAC, and I'll have the turbocharged Kia Rio with a giant spoiler on 20" rims of laser projectors.

DogP

[tribble]

Good on ya for keeping the spencer banner flying, DogP! Did you consider just replacing the entire red diode carrier with a DTR module? I had a hell of a time pressing the tiny blue diode in to a holder once and have figured I am just not going to mess with that level of component if I can help it. :-) Been a busy summer, but looking forward to playing with the spence once winter rolls around again.

[VibrationsOfDoom]

Due to a user's suggestion on here, I have ordered a blue/violet diode and am waiting on it to get here... That way, I can replace the one that's no longer working in my unit (said to be an exact fit), so here's hoping I can get my absence of blue problem fixed SOON...

[DogP]

Did you consider just replacing the entire red diode carrier with a DTR module? I had a hell of a time pressing the tiny blue diode in to a holder once and have figured I am just not going to mess with that level of component if I can help it. :-)

Heh, yeah... I would have just replaced the whole module (or ordered a press) had I known that the holder was press fit. The blue one had a threaded holder kinda thing that screwed in place to hold the diode in, so I figured the red was the same way. Once I pulled the module and removed the hot glue covering the diode, I noticed that it was pressed in. :/ Of course I'm way too impatient to wait for a diode press, or replacement module... so I knocked the old one out with a small bolt and a hammer, and pressed the new one in with a small rolled up piece of aluminum and a vice. It worked, so I guess I made out on my cheap diode replacement.

BTW, I looked more into replacing the green diode with a direct diode like the PL520. Unfortunately, I don't think it'll work without several modifications, due to the diode needing about 5.8V at the lasing threshold. The blue driver is connected to the 5V rail (which is actually running at ~5.6 volts), and the red and green drivers are running on a ~2.8V supply. So even if you bumped the green over to the same rail as the blue, you still couldn't hit the lasing threshold on the PL520. And the stock driver has a max input voltage of 6V, and a drop of around 100mv, so you'll get around 5.9V max if you brought in your own 6V (would probably output ~20mW, and probably be a bit temperature dependent). It'd probably be best to either switch from a high side driver to a low side driver, or just replace the driver. The problem with replacing the driver is that most small/cheap drivers seem to be pretty limited in modulation frequency (and not all like the higher voltage that these need either).

DogP

[christek13]

Yes, I can use much higher speeds than before without artifacting! I think I have the same "extended range" as you documented earlier. 31 was sparkly, but 27 is not. I have not tried all the intermediate speeds yet. I will try re-tuning at 8 degrees at some point, but right now I am having way too much fun with my spirograph generator, and I owe James a rewrite of the spencer effect as well. :-\ And there's overtime to do right now, and then taxes to file... ah, well.

You know, I discovered that this unit happily sits upside down on its base; lets all the heat rise straight off the "base" plate into the air, not that there's much heat to be had.

Tribble did you ever have a problem playing larger .ild files on your projector? I can't get your Tron file to play or any other large files for that matter. I did format with a 512-byte allocation which definitely improved the time delay in between files.

DogP, Tribble, James: I've been following this thread for a while now and finally had to join to thank you guys for all the work and debugging you have been doing on this projector.