Full Version: After market laser pointer
From: MR C (MOSHE) [#1]
6 Feb 2007
To: ALL
I just figured out how to get the red dot feature in my engraver for $1
I bought a laser pointer in the dollar store and I shine it directly into the last mirror that is connected to the lens.
Presto! I have this neat feature!
Am I a genius?
From: Dave Jones (DAVERJ) [#2]
6 Feb 2007
To: MR C (MOSHE) [#1] 6 Feb 2007
From: Laser Image (LASER_IMAGE) [#3]
6 Feb 2007
To: Dave Jones (DAVERJ) [#2] 6 Feb 2007
He didn't say it lined up, he just said he had it now... :/
My method is similar, but it does get tiring standing above my laser moving the pointer back and forth though. >.<
From: MR C (MOSHE) [#4]
7 Feb 2007
To: Laser Image (LASER_IMAGE) [#3] 7 Feb 2007
From: Laser Image (LASER_IMAGE) [#5]
7 Feb 2007
To: MR C (MOSHE) [#4] 7 Feb 2007
That is probably true but you need to have the beam aligned with the laser to have any practical purpose. Light reflects off of the mirror in a direction based on the angle it hits the mirror. If two light sources hit a mirror from a different angle they will land on two different spots, so your red beam won't be very close to your laser beam. To illustrate this get two laser pointers and tape, or hold, them together. Point them both at a mirror and you will have two dots reflected off of the mirror.
I don't have a physics background to give you a technical explanation, but believe me, your method won't give you a very good result.
You might have better results if you attach the pointer to the head and point it where it should be. This way you don't have mirrors to throw things off.
Gary
From: PenTrophy (PENINSULATROPHY) [#6]
7 Feb 2007
To: Laser Image (LASER_IMAGE) [#5] 7 Feb 2007
I don't know.... ........maybe I'm more positive.
On my laser you can pull the last mirror off and set a jigged red dot pointed.
Shoot a test beam to establish a "sweet spot"
replace mirror with jig.
then adjust the pointer to hit the spot
replace back to the mirror and then lase.
could work great...!
From: Laser Image (LASER_IMAGE) [#7]
7 Feb 2007
To: PenTrophy (PENINSULATROPHY) [#6] 7 Feb 2007
Just because I doubted myself I decided to find the answer.
"The law of reflection states that the angle of incidence equals the angle of reflection."
In other words, the angle the light hits the mirror is the same angle it is reflected. If you have two beams of light that are from two different sources, they can't possibly hit the mirror at the same angle so they can't reflect to the same spot either. Same thing when playing pool, the angle your ball hits the rail is the same angle it bounces (barring english, defective rails, etc.).
If you want a detailed explanation go to the link below and you can read all about reflective light and angles of incidence and refraction.
http://en.wikipedia.org/wiki/Reflection_%28physics%29
Gary
From: MR C (MOSHE) [#8]
7 Feb 2007
To: PenTrophy (PENINSULATROPHY) [#6] 7 Feb 2007
From: PenTrophy (PENINSULATROPHY) [#9]
7 Feb 2007
To: MR C (MOSHE) [#8] 7 Feb 2007
Yaaaaaaa. I win... I am a weinner!!
Thanks
From: John (ICTJOHN) [#10]
7 Feb 2007
To: MR C (MOSHE) [#8] 7 Feb 2007
Not knowing the style of mirror/lens assembly on your machine, If you put the laser light in the opening, won't that block the Laser Beam? or worse.... burn up the laser pointer? :/
From: Harvey only (HARVEY-ONLY) [#11]
7 Feb 2007
To: MR C (MOSHE) [#8] 7 Feb 2007
When I first went to align my system I was surprised. It did not matter at what point of the mirror the beam hit, the spot was in the same place. The lens does that.
If the beam is entering at a very different angle it might, (might), make a difference, not sure.
From: MR C (MOSHE) [#12]
7 Feb 2007
To: John (ICTJOHN) [#10] 7 Feb 2007