VCSel Laser

[Fanie]

This is interesting (for some  )

I have these VCSel laser "torches" which I made dimable with simple PWM.
It works, but now look at the results 

This is a closeup of the light sources.  The reason VCSel lasers are safer than the single pin lasers are because the laser intensity per source is reduced and spread over the chip's surface, hence less likely to cause eye damage.  The collective light beam is also larger and is supposed to make a decent illumination area for night vision.


This is however the results I get... at about only 10m.  These sources are 5W and visible range should reach in the hundreds of meters.  Current supplied at PWM max is around 1Amp.


When the lens is zoomed out, each individual cell makes a bright dot with black surrounding it, the polka dot effect.  The bright dots are very dominating and bright.

This is when the brightness is reduced when adjusting the PWM.
You still see only the dots.


The only way it seems to get the laser light make a uniform light is to zoom the lens out, but that greatly reduce the light intensity as the light is then spread over a wide area and which requires a lot more current to drive the laser to maintain visiblity.

Could there be a way to keep the beam narrow without the individual dots showing ?

Here is another VCSel source.


This one does the same, you can clearly see the four blocks, although each block does give a nice clean visible view area.

This is what the light is supposed to look like, exposing mr rat clearly.

[Fanie]

The https://nightvisionforumuk.com/ have some excellent articles on the VCSel lasers.

Also have a look on Youtube and see what colour night vision can do.  It is unbelievable.
Makes one realize how limited our sensory abilities are.

I want to add.
There is a video on Youtube somewhere where someone shot a rat with a .30 pellet gun.  In slow motion the rat ducked and the pellet missed.  He then used a smaller caliber and managed to shoot the rat.  We cannot see these projectiles fly, too fast, yet some animals do.  Unbelievable reflexes animals have.  Just think of a cat landing on it's feet every time, even if you drop them from upside down.

The latest here however is, I have to get out of bed so the wife can get up so she does not disturb the cat !