i took apart the cameras and ir blaster.

quite interessting.

IR Blaster:

its very simple. On the outer rubber sleeve is a thermo sensor

the main component is a IR Laser Diode with a lens behind a diffraction grating.

undeaneath the Laser is a TEC / Thermo Electric Cooler to stabilize the temperature and the wavelength.

https://i.imgur.com/xfOYVNN.jpg

IR Camera

a specially coated lens which is quite big inside, behind that a IR pass filter and then the sensor. Looks like a CCD but quite a big one, large pixels = more sensitive.

https://i.imgur.com/lmk8HUG.jpg

Visible light camera:

well just a normal camera module. with a IR cut filter of course.

notice the die size, or the pixel area is much smaller.

https://i.imgur.com/Jl00bdB.jpg

IR vs visible comparison.

https://i.imgur.com/fxkKLxw.jpg