nova laser with three beams

[ben74]

if i shine my 75x on a mirror i can see three beams 2 weak 1 strong is it mode hopping

 

[Lorgar]

Its reflections main beam one off the surface of the mirror and one off the back of the mirror that is why so many people use front surface mirrors you dont get multi reflections

 

[ben74]

theres just one mirror and i put different batteries in and there five beams is it mode hopping

 

[Lorgar]

The main problem is that the glass face of the mirror will also reflect the beam not just the silver on the back of the mirror
To find out if its mode hopping you need to shine it through a lens and look for more than one dot
Dont use a mirror as they cause reflections
Point it at a wall from 20+ feet and take a pic
If you see one dot on a wall I would say it is not mode hopping
Mirrors will always make multiple beams depending on the angle you hit it at
Unless its a front surface mirror (silver on the front not behind the glass)

 

[jamilm9]

what does mod hopping mean and why does it happen.

 

[rubberband]

mode hopping is when the beam of the laser shifts modes from say tem00 to tem01 which means 1 beam to 2 beams.

this is caused by defects in the crystals in the laser which causes it to heat up and thus mode hop.

Thanks,
MItch

 

[Cyparagon]

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