I was looking at exactly the same pages you were. Try reading those articles (or use ctrl+f) if you want to know where the filter discription is from.

You don’t need to concoct a fictional story about where the information came from. Its clear your purpose here isn’t to inform anyone at this point. If you’ve ever talked to an engineer prior to this you would not have this opinion of my colleages.

And the analogy here is so bad. If the solar panel were partially transparent and part of system was dependent on that transparency.

Engineers say its “acting as a filter” because thats a way of analyzing the system. For all and intents and purposes anything can effectively be modeled as a filter in certain design situations has been called a filter. So yes, engineers do talk like this.

Source: used to work in an electronics hardware development lab with electrical, optical, and software engineers.