Topic: $400 RGV 30kpps Chinese projector

[Xer0]

Mhh... we have very mean customs here in Germany
i hope the taxes wont rip me my pants of. 19% at least + some % i dont know yet
but there is still hope it will slip through without notice

Yeah sure. The SKU15764 "unrefined DAC" is collecting dust here. i still have to figure out how to build the correction amp and supply it with ±15V to get full scan angle. There was a guy on PL who wrote how to use only 1 OPA for the Offset, so requiring only 6 of those for XY & RGB. With a bit of SMD i plan to integrate everything needed right into the Soundcard Box, incl DB25!

[James]

Yea...... Ummmmm..... that guy would be ME! or perhaps someone writing about what I had already written about years ago.

Actually Dean Hammonds designed the LaserBoy Correction Amp for me and LaserBoy made it world famous!

Dean is meandean on this forum.

This has been on the Internet for many years.

http://akrobiz.com/laserboy/p_laserboy_95.html

You will not find any better source of information about the use of a sound card for a laser controller than right here at this forum.

I have built MANY of them and sent them to people.

I have also changed the design a little bit to make it much more accurate to adjust and to compensate for a wider range of offset and gain requirements.

http://akrobiz.com/laserboy/forum/index.php/topic,333.msg4033.html#msg4033

http://akrobiz.com/laserboy/forum/index.php/topic,277.msg3002.html#msg3002

I would be glad top help you. 

James. 

[Xer0]

Well i cant acess PL right now (what the heck is going on - PL down?!) but if not you who then

My problem will be - where to get ±12V? The DC/DC someone posted at LPF i cant get here in Germany. besides Digikey, but they charge 30$ for shipping a single chip. wth?

So i could only mod the ILDA connector in the Projector to refeed me ±15V from the Galvo Amp to my DAC through unused pins of the DB25 Cable. Or i have do some other sort of magic making the 5V at least double for each polarity. maybe some kind of kascade? Or building a DC DC converter myself from a ripped USB Car Charger?

[James]

That's funny. I can't access PL, ever!

I have some of the original printed circuit boards that drlava and I made for the kits. I also have some of the DC/DC converters.

http://akrobiz.com/laserboy/forum/index.php/topic,335.msg4091.html

James. 

[Lazerjock]

James, if you have enough of them, I would like to upgrade my DC/DC converter. Will you sell one? It's something I'e been meaning to do for some time..

Thanks
Chris

[Xer0]

Mhh are them those ±12V Converters? If yes i could need one.

Or do the Galvo Amps need even more Voltage to get full scan angle?

Afaik drlava uses the ±9V ones which give just about 8°

[James]

Afaik drlava uses the ±9V ones which give just about 8°

Uuuughhhhhhh!

James. 

[Gadget]

Xer0, let me know when you get yours. Id like to compare the Ilda frame output. still dont know if its ishow DAC or something else causing my frame to look flickery, cant even take a full pic of it even at 30kpps.

[James]

DC/DC

http://www.newark.com/xp-power/ia0509s/dc-dc-converter/dp/88M0693

James. 

[Lazerjock]

Thanks James I ordered one.

[Xer0]

Mine is here! Refer to http://tinyurl.com/yl994uv for first test run Pics & Vids

[BenDarkFox]

Was talking to James on the phone and promised him I would post this

http://www.chinesedepartmentstore.com.cn/osc/product_info.php/products_id/1700

seems pretty nice, theres more info (and inside pics) here: http://www.photonlexicon.com/forums/showthread.php/9417-300-mw-R-G-B-Chinese-Projector-399-00

(pics of the actual projector in post #14)

seems like a nice little starter kit... adjustable mounts!

all for $400? anyone going to bite? really would like to see pics of it in action

Looks like a great package for me to get started with, at least it's a lot better than what I would of gone for. I wonder if they still got it.

[James]

You would get something that works! It won't be super bright, but if the specs are true, it will look very nice in a totally dark room. Looks like it says 635nm red. If that's true this appears to be about 8 to 10 times brighter to human vision than the 658nm DVD burners. The green is pretty much a given 532nm. The question is how is it modulated? Or for that matter how are the others modulated? Looks like the blue is a 473nm. That is even more complex than a 532 green. There are two types of solid state lasers. One is a direct injection diode, where the energy out is what you see is what you get. These lasers are easily modulated by one of drlava's diode drivers. Then there are Diode Pumped Solid State or DPSS lassers. These have a high energy pump diode that puts out a lot of 808nm, more or less invisible IR. This floods a crystal of some kind possibly NdYAG with energy to lase at 1064nm, even farther into IR, and this goes through a KTP crystal to somehow cut the wavelength in half to be the 532 green we can see. The 473 DPSS is a bit weirder than that. Forgive me if I got some of this screwed up, but this is about what goes on. The problem is that the crystals in front of the 808nm pump diode are very temperature sensitive and they are getting pumped with what amounts to thermal energy. So there are all kinds of instability issues as a result of thermal hysteresis. These issues cause problems with how fast the laser turns on, how bright it gets and how well it can be modulated from off to full on in any reasonably linear fashion. A MUCH BETTER blue is available in the form of a direct diode laser at 445nm. That would be an obvious replacement. I would say that this only gives you on and off on all three colors. That means that as is, it will only give you 7 different combination of red yellow green cyan blue magenta white. Oh well. You would also get some dichroic glass filters that would allow you to combine just about any reasonable replacements for the RGB lasers you get in the box.

James. 

[BenDarkFox]

I received the package today and tried it out    it took about a week to ship which is pretty awesome, didn't have any hassle with pricing or that either.


I knew the risk of getting lower specs than mentioned and they are right, I'll post according to what's in the manual.


rated voltage: AC85-265V 50Hz-60Hz(Auto-adjust)
rated power: 10W
laser power: R150mw/G50mw/B150mw
laser wavelength: G532nm; R650nm; B405nm
20Kpps scanning(not 30K)
control mode: stand alone, music/mic, DMX512, ILDA


I also got the interface and software with it in case just to get something going, it works out really well. The lasers are really bright, i tested it with the lights on and dark colored walling, all colors show brightly except violet but still visible, though that is expected as violet is the least visible color. The scan rate isn't perfect but it's enough to see things moving about and in action. some moving frames of people run fludily while complex patterns flicker. I'll do some more testing around and see what works and what doesn't. Thanks a lot for the info and glad to provide anything that I can. Maybe I'll be lucky and get to take some pics or a video of what it actually looks like in action.

[James]

I bet you could get some help on this forum for tuning those scanners to do a much better job. Be careful of the 405nm. It is a lot more powerful than you might think. You can't see it very well because it's at the very top end of the spectrum. But there is a lot of energy there at a wavelength that is particularly damaging to just about any living tissue.


The first thing I would replace is that 405nm diode for a 445nm blue.


James.