8th annual South Eastern Laser Enthusiast's Meeting, Aug 14-17 2014. Sign up now!

[JohnYayas]

Nice. Sounds like it plus your deluxe lumia kit = awesome.

[SaltyRobot]

I could use some schooling on near field and far field alignment methods and will have my compact projector there. Not sure if i'll want to spend time working on it but could def use the tips.

[JohnYayas]

I could use some schooling on near field and far field alignment methods and will have my compact projector there. Not sure if i'll want to spend time working on it but could def use the tips.

It's a pretty simple, actually. You just have to get the beams to be perfectly parallel and combined before they hit the mirrors. For RGB you typically have 2 dichros with one beam going through both dichros and the other beams bouncing off either of them. The trick to alignment is to get the beam that goes through both of them where you want it on the galvo mirrors. Then, you look at the spot on the dichros that the first beam is going through and aim other laser on those dots on the dichro. A little fog or tissue helps since it is sometimes hard to see the spots on the dichros. That will get your short field alignment set up. Then, you just tweak the dichro adjusters so that the dots on the wall are all combined. You'll probably have to go through the process more than once if since your tweaking your dichros will throw off the near field alignment a little. Setting far field first, then near field, then far field will get you almost all the way there. That's how I do it anyway. I'd be interested in a better way, though.

[Lazerjock]

Len,
Is that you at Woodstock?

[JohnYayas]

Len,
Is that you at Woodstock?

LOL. Which pixel are you talking about?

[SaltyRobot]

John,

I get the general theory. I am looking more for what do people use to shim the diode mounts. Tips on how to get the near field alignment completed easily so the far field is a snap. I have built two projectors and one was with a RGB brick, so my alignment skills are lacking. I know SELEM is going to jam pack a bunch of knowledge into one place and the tips and tricks on something like this possibly can be easily demonstrated or explained.

It's a pretty simple, actually. You just have to get the beams to be perfectly parallel and combined before they hit the mirrors. For RGB you typically have 2 dichros with one beam going through both dichros and the other beams bouncing off either of them. The trick to alignment is to get the beam that goes through both of them where you want it on the galvo mirrors. Then, you look at the spot on the dichros that the first beam is going through and aim other laser on those dots on the dichro. A little fog or tissue helps since it is sometimes hard to see the spots on the dichros. That will get your short field alignment set up. Then, you just tweak the dichro adjusters so that the dots on the wall are all combined. You'll probably have to go through the process more than once if since your tweaking your dichros will throw off the near field alignment a little. Setting far field first, then near field, then far field will get you almost all the way there. That's how I do it anyway. I'd be interested in a better way, though.

[Lazerjock]

John,

I get the general theory. I am looking more for what do people use to shim the diode mounts. Tips on how to get the near field alignment completed easily so the far field is a snap. I have built two projectors and one was with a RGB brick, so my alignment skills are lacking. I know SELEM is going to jam pack a bunch of knowledge into one place and the tips and tricks on something like this possibly can be easily demonstrated or explained.

His name is actually Gary not John. We will have to get the story behind the screen name.

[buffo]

We can have a little round-table discussion on projector alignment at SELEM. Probably would dovetail nicely with the scanner tuning and palette adjustment talks...

Adam

[JohnYayas]

His name is actually Gary not John. We will have to get the story behind the screen name.

It's a Buckaroo Banzai reference. All of the aliens have the first name "John". Like John Smallberries, John BigBootay, etc. There is one point in the movie where this official dude grabs one of their name badges and looks at it and says "John Yayas!" I thought it was funny and it has stuck with me.

[swamidog]

His name is actually Gary not John. We will have to get the story behind the screen name.

probably a better choice than john smallberries..