Non blanking projector / flicker

[markmtts]

All the answers you need should be around here somewhere. You can easily spend hours reading up on builds, machining, electronics, diodes, housings, knife edging, scanners, reviews, sellers and the search function is your friend if looking for something specific. There's plenty of advice and expertise, just no silver plate

[Galvonaut]

Wes, Sam's Laser FAQ is also really really handy. I build my first projector thanks to this and scouring PL.

The best single thing you could do is probably replace the galvos, or maybe start building your own, which is probably better value for money as you will get what you want.

I think everyone who comes here not knowing how to build a projector just has to read and read and mess about with things. If there is a specific technical problem you have, then ask, otherwise you will get a vague and usually very expensive suggestion :P

Keith

[bungy]

The best single thing you could do is probably replace the galvos

I agree. I upgraded my chijector to DT-40W scanners from goldenstarlaser and I'm very happy with it now. I also wired the laser drivers directly to the ILDA connector for complete control. All the other original internal electronics are bypassed. Of course I don't have any built in effects now, but I don't care as I only wanted to use the projector with ILDA.

http://www.photonlexicon.com/forums/...de-Help-DT-40W

[dnar]

Hi Wes, I guess I should offer an apology for being so rude. You have to understand however that most members here and the (mostly serious) discussions are pretty much advanced subjects. Also, I personally don't have much regard for the cheapest laser gear (and I have seen a lot of it during my travels of China) and I know it's bad economics to try and make it do something it really is not capable of. Don't get me wrong, some of the low end parts are used by people here me included. They can have their place.

The point I am trying to make is this, really low end Chinese projectors are pretty poor, in fact your doing really well if you can project a half decent IDLA test pattern AND have the unit reliable stable for any period of time, not to mention safety which for me is #1. Don't expect much from low end projectors with their low end scanners, modules etc. As I said, it's about expectations. You you might be able to improve what you have, but trust me, you could find yourself then wanting to improve the next issue such as perhaps lineup. Then we will recommend you replace the glued-in-place dichro optics and while your at it the dichros themselves. Next your not happy with say modulation between the various lasers, so we go down the path of replacing modules, or changing out the drivers. It really can very quickly turn into a case of "buying a Skoda and slowly converting it into a Ferrari". If a Ferrari is what you want, best starting with a Ferrari.

As pointed out above, there are tons of good resources including the Wiki here. Another good source of info and help (help I suspect your after) is at laserpointerforums.com

Perhaps it would help if you outlined your expectations with this projector and photos of the internals and the scanned image, so we can better guide you.

Regard, Wayne.

[wes702]

Thank You All for the replies. Getting started in lasers is alot like your first car when your 16. Its not a mercedes, mine was a 1964 Nova II. It was a piece of crap but it allowed me some time to learn how to drive, learn what makes it tick and experiment on parts replacements...Didnt keep it long, learned some lessons and then sold it....Bought something else...blah, blah, blah..
After opening up my X periment Chiprojector and watching it operate ive observed that it has poor color mixing, i believe its due to the green module operating all the time. when i cut it off with a piece of paper, i get great red ( 638nm @ 200mw, so it says on module) and nice blue (445nm@ 500mw, so it says) im seeing alot of green bouncing off the dichros ( cheap dichros?) and i also noticed that the red and blue put out beams that are elongated (not round) and that may contribute to color mixing.
I am more interested in beam shows so scanners might work or even just bump up to 30K. Are the 40dt wides mainly for graphics, etc....as they seem way kinda spendy for upgrading this thing...With that all said, im thinking i can start with adjustable dichros first, then move onto modules upgrades. Question, can the oblong beams be tweaked to produce round? adjustable focus?
Also, ive searched for the "holy grail" flashlight fail" etc but havnt found the 55 pages relating to a projector build. anyone have a URL?
Well thats my story and im sticking to it.....

[bungy]

I think the dt40 wides are great for beam shows. The scan angle is huge so you can create much bigger effects. On a recent foggy night, I set up my projector in the back yard and set the projection zone to the entire width of my house. I set QS on autoplay, and we sat right by the house looking back at the projector. It was like being back at the auditorium at SELEM!

[m0f]

On a budget, the dt30's are great too and can be had for close to half the price of dt40w's. Another advantage of the dt30 or dt40pro's over the wides are that larger mirrors are available as an option when purchasing. It's typical that lower cost lasers (and many higher ones as well) these days have beams larger than 3mm. So with the 3mm aperture on the dt40wides it's likely that not all of the beam will fit, which can make for quite a bit of lost laser power.

If using high quality, tight beam laser modules, the dt40wides can be a viable option (opsl, lower powered 637 module, etc) But anything with a 638nm red and without telescoping the beam to fit, you're going to be losing a lot of power, and for blue as well.

I have a set of wides on the shelf not in use at all just for these reasons. I'll be building a low powered single mode diode laser soon which then I'll finally be able to put them to use again.

So my recommendation for scanners is the DT30's, or DT40 pro's (if in price range), but for either one the large mirrors (5mm aperture) is a must.

As far as width, I get plenty with DT30's, more than usually need. And honestly I find the DT30's to be very close overall to the 40's, just can't push them quite as hard when doing graphics. The build quality looks identical, almost looks to me like they're one in the same and just binned based on performance. Far far better quality than the slightly cheaper pt series for example. Which makes the dt30s probably best bang for the buck imo.

Here's a pic, where two of the lasers are using dt40 pro's and two of the lasers are using dt30's. There's no visible difference in beam shows. Width was only set to about 2/3rd, running at about 28k though they could have been pushed harder there was no reason to. If you're planning very graphics intensive content or looking for higher speeds, the dt40pro's or better scanners are worth it, but I guess my point is that the dt30's are surprisingly nice for the price.




As far as the rest of the projector, either replace the green with a better module (as smaller modules are cheap enough) or could save a bit more by just replacing the driver with a proper driver (use the existing one for the tec) and a decent analog driver for the diode.

If the red and blue blank properly, just look at beam correction optics to clean up / tighten up the beams, which can be done reasonably cheaply. Or could spend a little more and replace the drivers as well for perfect analog blanking. (Perhaps pickup a quad driver and you can drive all 3 lasers properly with one unit)

So for sure your laser can be fixed up to work half decently for minimal spending if you're up for a bit of tinkering.

[wes702]

Thank You, sounds like the begining outline of a plan..I am a decent tinkerer..my mentality is that if I can't fix something I will scrap it and use the pieces to build another. (Frankenstein syndrome) it lives! It lives! So please direct me to a source of these correction optics, drivers, etc. Etc..

[wes702]

A Paul Harvey moment...and now for the rest of the story..
So i decided to get a closer look inside the workings of my XChiprojector today after something was nagging me. These bundled up wires, were do they all go, from here to there..look at the markings..match them up..oh my why is that small 2 wire connector not plugged in to something...it traces back to the green laser driver..is it important? hmm...oh why is there nothing plugged into the SD card panel that is marked G, right next to the R and B plug. Lets see what happens if i plug the loose connector into the empty spot.....flip that power switch! WOW no more green trace lines and my red and blue colors are there...woohoo!
Yes, it appears the green driver works, it just wasnt plugged in when it was shipped and it has taken me this long to figure it out...(can i say "shit" here?) Now maybe if i can correct those rectangular beams (445/638) and install some adjustable dichro mounts i may be on the way to having something that i can entertain my simple self with....
Just Thought id share my "aha" moment...