As you enter the library of the Tower of Terror, you will notice a lot of random things in the room. Located underneath the television that plays the preshow is a pair of broken glasses that you might not ordinarily pay attention to but these glasses aren't just random. They are there for a very important reason.
The broken glasses you see are a reference to a Twilight Zone episode. When Imagineers were working on the Tower of Terror attraction and settled on a Twilight Zone theme, they watched each of the 156 Twilight Zone episodes at least twice to get a good sense of the mood of the television series and how they could apply it to the attraction. Many episodes were screened every three or four times and in them, Imagineers looked for props that they could put in their new attraction to make it all seem a little more authentic.
The glasses you see here are from one of the most famous episodes in the Twilight Zone, called "Time Enough at Last". In the episode, Harry Bemis (Burgess Meredith) is a man who loves to read but can never find the time to read a book because both his wife and boss think it's a waste of time. After a nuclear bomb goes off that wipes out mankind, Bemis is the last man on Earth left. He finds a public library in tact where he can finally read all the books he ever wanted, but drops his reading glasses and they break.