IR beam

[marcuss]

Hello,

I have noticed that the section of an ir beam is actually a rectangule viewing it with the naked eye but viewing it through a camera it is a circle. How do you explain that?

 

[diachi]

The IR beam is most likely a rectangle as you are seeing it. Diode lasers usually do have rectangular beams. Your camera probably sees it as a circle because it is much brighter to the camera than it is to you. If your going to be using IR lasers you should get the proper safety goggles, it may not look bright, but in reality it is.

-Adam

 

[Switch]

it may not look bright, but in reality it is.

No, it's not.It's powerful though. :

Lower powered single mode diodes probably have a round-ish beam, like red or blu-ray diodes.The higher powered one, that are multimode (>500mW) have all sorts of weird shapes.I guess it depends on the diode.The really powerful ones, like the multiwatt "bricks" project a long rectangle, almost like a line.

 

[diachi]

it may not look bright, but in reality it is.

No, it's not.It's powerful though. :

Lower powered single mode diodes probably have a round-ish beam, like red or blu-ray diodes.The higher powered one, that are multimode (>500mW) have all sorts of weird shapes.I guess it depends on the diode.The really powerful ones, like the multiwatt "bricks" project a long rectangle, almost like a line.

Well it is bright your eyes just aren't sensitive to it so it doesn't actually look bright, a camera would see it as bright

But yeah your more right than me

 

[marcuss]

The really powerful ones, like the multiwatt "bricks" project a long rectangle, almost like a line.

I managed to adjust the focus and actually, at a certain point, it becomes a very thin rectangule, like a line as you said. It's also possible to make a square. It all depends on how you focus the beam.