Oh! yes, I did love the idea behind those red sunglasses :-)
He uses them so he doesnt see bright lights in the last hours of the day. I heard many times that is not natural.to have lights, screens... until late in the night.
Our grandfathers went to sleep when sun went down as we are diurn animals. Those days humans followed the natural circadiam rithm. Around 10 was bedtime.
Nowadays with our lights and tvs and all that artifcial stimulation our circadiam rithm is broken. It looks like repair that one is an important step on health recovery.
Thats why his idea of this glasses is brilliant. And they are so inexpensive! I want a pair really. Even if my grandma thinks Im nuts.