[torginus]

I was just watching this video about a Chinese piece of industrial equipment, designed for replacing BGA chips such as flash or RAM with a good deal of precision:

https://www.youtube.com/watch?v=zwHqO1mnMsA

I wonder how well the aftermarket memory surgery business on consumer GPUs is doing.

[ThrowawayTestr]

LTT recently did a video on upgrading a 5090 to 96gb of ram

[dotancohen]

I wonder how well the opthalmologist is doing. These guys are going to be paying him a visit playing around with those lasers and no PPE.

[CamperBob2]

Eh, I don't see the risk, no pun intended. It's not collimated, and it's not going to be in focus anywhere but on-target. It's also probably in the long-wave range >>1000 nm that's not focused by the eye. At the end of the day it's no different from any other source of spot heating. I get more nervous around some of the LED flashlights you can buy these days.

I want one. Hot air blows.

[noosphr]

It's 45w of lasing power. I have a scar on my hand that's 15 years old from running one of those at 10% power and getting a reflection from a bare metal sheet.

This will absolutely scar, if not char, your cornea faster than you can blink.

[CamperBob2]

That's (again) less energy than a flashlight puts out these days, so the beam had to be tightly focused in your case. That isn't how these things work.

There is nothing special about "lasing power." It amounts to a 45-watt light bulb, nothing more and nothing less.

[dotancohen]

A 45 watt light bulb spreads the energy in all directions - at 1 meter away that's about 3 watts in every square meter or roughly 0.000003 watts per square millimeter. The laser is putting 45 watts into that same square millimeter at the same distance.

Of course the laser is tightly focused. That's pretty much one of the defining properties of laser devices. How else do you think the laser is heating the microprocessors in the video?

[CamperBob2]

They will be using a beam spreader to conform to the size of the targeted IC, which is usually on the order of 5x5 mm and up. For smaller parts they will be reducing the power.

They shouldn't be focusing it to a point under any conditions. Whether it's as safe as it could be is a different question, of course. For instance, you'd like to think that the act of configuring it for a smaller beam footprint would reduce the power at the same time, as opposed to requiring a separate adjustment that might be overlooked by the operator. Would have been nice if the video had addressed that and other safety considerations, for sure.

A lot depends on the exact wavelength. 1400 nm and longer is much less worrisome than near-visible IR.