I would highly suggest you conduct the same experiment at home, as you said it's quite easy to put together the test environment. Though you can also just google "photonic barrier" and read about it without the experiment. Again, maybe I'm not using proper word choices for things, so someone with a stronger physics background looking at my words through a pedantic lens might find issues with them, which is fair. But basically, if someone shines a light at you, and you shine a light back at them, you are blinded if they hold a significantly stronger light source. You are not blinded if you are holding a significantly stronger light source. And there's an array of in-between states depending on the exact light output of each. This phenomena is referred to as a "photonic barrier." Please show a scientific study or anything that refutes this, because looking around, I find nothing. A large group of people with actual experience running these experiments all had the same observation about photonic barriers, and you just saying "do the experiment at home" doesn't negate them or their observations at all. But perhaps you're on the verge of a break through if you know something we all don't. And I'll go so far as to say that it's possible that you do, but so far my observations have been the same as theirs. In my opinion, that puts the onus on you, not me, to make your case.
Photonic barrier doesn't seem to be a widely standardized or accepted term. The closest to what you're referring to seems to be something to attenuate effect of light on night vision equipment.
But back on topic: light cannot block light. First result on google. https://physics.stackexchange.com/questions/456409/can-a-lig.... Though I'll concede you a point in that, if their pupils are contracted more because they're using a brighter source, then the impact of your beam on them will be lower than theirs on you. That being said, I'd wager to say that the difference would probably be marginal, given that we're talking about light reflected at night (which would leave you with a pretty big dilation in both LED and halogen) vs. looking directly at a light source.
