simple question regarding...

[wes702]

Im curious why low end chinese projectors use large mirrors on stepper motors. Im speaking about those long rectangular ones. ( 2 x 3/8")
Is there a reason they use these vs the small mirrors used on galvos. I have a rgy CR unit and a shinp blue unit and both have these. Also, as an excercise in education in upgrading, parts changing. How dramatic would these benefit from installing galvos at 15-20k ?

[Galvonaut]

Until very recently, the manufacture of stepper motors and the electronics to drive them has been a lot cheaper than real galvos. Thick old bits of glass are also a lot cheaper to manufacture.

The reason they use different mirrors is that a stepper motor works well with heavier loads, where as a galvonometer does not! A stepper motor is slow, where as galvos are very fast. There is no comparison between stepper motors and even slow galvos. Well worth doing.

Keith

[buffo]

Another reason for the larger mirrors is the fact that the cheaper projectors typically have poor beam characteristics, so a fat mirror is actually helpful in that it allows for more of the beam to land on the mirror.

Adam

[Galvonaut]

Another reason for the larger mirrors is the fact that the cheaper projectors typically have poor beam characteristics, so a fat mirror is actually helpful in that it allows for more of the beam to land on the mirror.

Adam

Yes, also I suspect it aids in alignment (probably little need for any).

Keith

[wes702]

Thank you for the feedback. If i ask enough questions/read over time, I just might have a clue to what its all about..

[Galvonaut]

Thank you for the feedback. If i ask enough questions/read over time, I just might have a clue to what its all about..

Yes, you'll pick it up. I try and read everything that's posted and I'm even learning a bit about gas lasers - something I had little interest in.

Keith