what is the difference between beam modes TEM00, TEM01, TEM02

[trever22]

i hear all this talk about the different beam modes (TEM00, TEM01, TEM02) but what do they mean

 

[blackspirit]

Im sure someone will explain in more detail, but heres a picture

Cheers
Dave

 

[ped]

Allways wonderd that but was too lazy to search.

Hey at least i'm honest!

Nice info.

 

[phoenix77]

A good beam, A crappy beam, & a crappier beam, LOL :crackup::crackup::crackup:

BlackSpirit has it right :wave:

 

[ipod]

A good beam, A crappy beam, & a crappier beam, LOL :crackup::crackup::crackup:

BlackSpirit has it right :wave:

the lower the TEM the better the beam? how does one measure it?

 

[qumefox]

You measure it by expanding the beam and seeing what you have.

In most lasers though, higher modes mean more power. DPSS lasers would be the only case where sometimes this isn't true. It really depends on the cavity design. For most handhelds, usually the TEM mode doesn't matter since all your doing is pointing them at stuff.

When lasers are used for 'real science' as I call it. Holography, particle counting, etc, is when a stable Gaussian TEM00 beam is required.

 

[ThePhotonist]

Thanks for the info back spirit +rep

 

[diachi]

Thanks for the info back spirit +rep

This thread is nearly 6 years old - it was last posted to in 2010. You should avoid bringing back such old threads unless you have something new to add. Just a heads up.

 

[paul1598419]

For He-Ne lasers, TEM01 is called donut-moding as the beam looks like a donut hole. it looks like a light beam with a dark spot in the middle. This is caused by destructive interference in the middle of the beam. It is especially bad when trying to make holograms.