Orpington Astronomical Society

Astronomy => Technical => Topic started by: RobertM on May 25, 2009, 11:24:13

Title: Collimation of Laser Collimator
Post by: RobertM on May 25, 2009, 11:24:13
Having a but of trouble with this.

It looks like the laser is off square enough that it's impossible to get the beam in line and parallel with the body.  I don't think I'm doing anything wrong but I would be grateful if someone could double check what I'm doing.

1) square up the laser body in the tube to start.
2) adjust the front set screws so that the laser is coming out of the middle of the hole in the reticule screen.
3) adjust the rear screws so the beam projects to a spot that doesn't move when the laser is rotated through 360 degrees.
4) repeat 2 and 4 till no adjustment is necessary.

When I follow this procedure the laser beam is part obscured as it comes out of the hole in the body so doesn't project a circle any more and I've run out of adjustment !

Thanks
Robert
Title: Re: Collimation of Laser Collimator
Post by: JohnP on May 25, 2009, 14:18:37
Robert - don't know if it helps but you could also try getting yourself a piece of accurate right angle bar. Then place collimator on this & point at a wall say 10ft away or so then rotate collimator & watch the spot. Adjust screws to move point half way back...

John
Title: Re: Collimation of Laser Collimator
Post by: RobertM on May 25, 2009, 15:47:22
Thanks John but I'd run out of adjustment on the screws.  Have now taken the laser apart and it looks like the rather cheap nasty plastic lens was off square and throwing the beam out, at least it's coming out parallel to the body now !
Title: Re: Collimation of Laser Collimator
Post by: RobertM on May 25, 2009, 16:16:45
Now sorted - it was the lens !!!