controlling the opacity of some glasses

Hi there,

i am searching for a way to build "glasses" in which i can control the sight of the people who are wearing them.
So i want to make them blind or seeing.

The only point really is, that i want them to be "wearable" or not tooo heavy so you could use them in the field.
Not saying they should be "super small"... they also can look fancy...

i did found something interesting here:

What i found interesting aswell was to use some LCD-Screens as shown here in the yt-video:

(Just scoll to the end to see the result)

Maybe i could use just 2 small screens from some used or broke stuff/mobiles or so from ebay to control the opacity of my glasses.

Thx in advance for your help

You could try Kerr Cells, but you may not like the power pack.

How about adding additional pieces of Polaroid to an existing pair of Polaroid sunglasses in front of the original lenses. Use a micro servo to rotate the extra piece and you can graduate the ability to see from 100% (albeit with shades on) to zero.