why are blu-ray lasers so dim?

[cyclonite]

Hi all,

Just curious to know why blu-ray lasers are so dim compared to red ones? I could point a red laser at half a mile away and see the dot but I can't see a blu-ray's dot clearly on my neighbour's wall. Is it because our eyes can't pick up near ultraviolet as well as visible light?

Also, the blu-ray beam appears to diverge more. The red stays sharp in a dot over long distances but not the blu-ray.

Thanks all.

 

[Glutton]

The dimness and divergence are due to the wavelength of blu-rays.

The eye does have a hard time seeing the near ultraviolet light and the divergence is just an illusion... it does not actually diverge the way you see it, its is just the way your eyes perceive the beam.

 

[daguin]

I need to update some stuff in it, but here it is

Observations about Blu-Ray lasers - Laser Wiki

Peace,
dave

 

[Invader Zim]

our eyes can't pick up near ultraviolet as well as visible light

I think that this IS the answer.

 

[cyclonite]

fantastic wiki dave. thanks for that

 

[daguin]

fantastic wiki dave. thanks for that

You're welcome. I need to update some stuff about the "newer" diodes.

It used to be stickied herein :undecided:

Peace,
dave

 

[lasersbee]

Here is a chart to show what wavelengths/colors are most or least sensitive
to the human eye...

 

[themandalorian]

Awesome graph laserbee! I wish we could get 556nm lasers

 

[X FLY]

There are 556nm lasers

556 nm yellow green laser.

 

[realista]

i can't understand one thing........... why in the graph red is more visible than bluray? i have a bluray.. 80mw... and it has a lot better visible BEAM...... my 200mw dilda.. is worse. .....

 

[daguin]

i can't understand one thing........... why in the graph red is more visible than bluray? i have a bluray.. 80mw... and it has a lot better visible BEAM...... my 200mw dilda.. is worse. .....

These are "average" responses. You may be different.

Peace,
dave

 

[iskor12]

i can't understand one thing........... why in the graph red is more visible than bluray? i have a bluray.. 80mw... and it has a lot better visible BEAM...... my 200mw dilda.. is worse. .....

I think that it has a lot to do with how the beam is floresing with the particles in the air, which in its self creates a different wavelength than the laser by it's self.

I believe that and that alone, is what makes blu-ray beams look brighter than reds.

 

[realista]

i am myopic... my mother see better the 200mw dilda... and i see better the 80mw bluray ehehe we are both myopic. bho. but i am happy to se better bluray than red.... red is "OUT".. violet is "IN" ahahahaha and even if bluray is not a laser to affascinating people with beam... in future i hope to have a 500mw bluray...i think an this power .. it could be comparable to a 30/50mw green....that is very bright by night.