So, I had my class today in Databases, but the subject matter is not important. What’s important is the projector that the professor used to teach the class. This is just an ordinary projector. It took video input from his laptop and shined it onto the whiteboard at the front of the class. I’m sure most of you have seen this kind of thing before. He was using Power Point to display various screens with white background and black text. The projector was bright enough that he was able to leave the ambient room lights on.
Then I realized the part of this that blew my mind. The black text being displayed was just the color of whiteboard it was being displayed on. That is, if a projector wants to display a black portion, it doesn’t shine any light at all on that portion. So, when I saw black text, I was reading the non-lit parts of the whiteboard surrounded by the lit parts. The text looked genuinely black.
Whoa.
The magic of pupil light reflex.