Smart People Wear Glasses

In the media, smart characters have a tendency to wear glasses. The association with the Hollywood Nerd archetype helps in modern works, although this trope is older than that. May be Truth in Television, as some say that since smarter people typically do more reading, they place more strain on their eyes and are more likely to develop myopia (nearsightedness). Some studies have gone so far as to claim that myopia itself is linked with open-mindedness and intelligence. On the other hand, glasses are expensive, so people wearing them will not risq them in sports or fights (but some may use contact lens instead).

In Anime, there is a commonly-used variant of this called Glasses-Kun: A Lancer who has black hair, is taller than The Protagonist, is always smarter than the main character, is relatively quiet, somewhat broody, and wears glasses.

In Real Life, there are lots of different types of people who wear glasses, but in fiction they are more rare. This is due to problems such as glare from the cameras in Live Action media, difficulty reading facial expressions, etc., and is the reason why when such characters are present it seems more significant. As proven by the examples, it is also why this trope occurs more so in Live Action, animated programming, and other pictorial media and less so in literature; it's a visual cue to the audience that the character is intelligent, yet is used sparingly because of the aforementioned difficulties involved.

This trope is an inherent part of The Glasses Gotta Go and Beautiful All Along, and often Hollywood Nerd. Super-Trope to Nerd Glasses. The invoked form of this is Purely Aesthetic Glasses. Compare The Short Guy With Glasses.

Anime and Manga

 * Ishida Uryuu from Bleach wears glasses and is number one in his class. He also perfectly fits the description for a "glasses-kun".
 * Shizuko from Kaichou wa Maid Sama, who is Good With Numbers.
 * Shin, the Cute Bookworm and Smart Guy in Saint Beast
 * Both Franz Heinel and Shinsuke Maki in Future GPX Cyber Formula. One is a Gadgeteer Genius with cars and a computer expert, and the other is a computer machinist who makes computer games in his free time.
 * Played with in Detective Conan. Shinichi is already very smart without glasses, but as Conan, he wears glasses so he wouldn't be recognized as a younger version of Shinichi.
 * Minamo Kurokawa and Chika Kodama in Yubisaki Milk Tea, who are best and second best of their year, both wear glasses. Later Hidari Morii who Minamo teached as well.

Comics

 * Dilton Doiley in Archie Comics.
 * The Polish comic book Tytus, Romek i A'Tomek has A'Tomek (a nerdy, math-minded kid), professor T. Alent (a genius inventor) and "Papcio Chmiel" (the Author Avatar).

Film

 * In Sucker Punch, both Dr. Gorski (in the asylum) and Blue (in the nightclub) have glasses, though they mostly only wear them when they need to take a closer look at something (They might merely be reading glasses, rather than corrective lenses). While Dr. Gorski is a psychologist, Blue is smart in that Dangerously Genre Savvy way.
 * Invoked by Elle Woods in Legally Blonde, when she dons glasses to appear smarter and more professional in order to help Paulette get her dog back

Literature

 * Ponder Stibbons in Discworld.

Live Action TV

 * Cookie from Ned's Declassified School Survival Guide.
 * The one and only Steve Urkel, an Extraverted Nerd from Family Matters.
 * A weird example as it's something of an informed trait: scientist Bennett on Dollhouse wears, as Topher so gleefully puts it, "glasses. On a chain!" She's apparently far-sighted because she only wears them when looking at computer screens.
 * Garcia, a computer genius, and her boyfriend Kevin Lynch both wear glasses. Though he apparently switched to contacts, flashbacks to Reid's youth in Criminal Minds shows that he had some of the largest glasses any child has ever worn, ever.
 * Buffy the Vampire Slayer: Giles, while not the resident genius, is the resident Mr. Exposition.
 * Also Wesley, although once he got on Angel, he lost them after a while.
 * Liberty, Toby, and Claire on Degrassi the Next Generation. Actually, if a character wears glasses on that show, it's almost a given that they're intelligent.
 * Daniel Jackson in Stargate SG 1.
 * And in an alternate universe episode where she never joined the SGC, we find Sam Carter wearing huge Nerd Glasses. Presumably in the regular timeline she just wears contacts. Either way, there's no denying that her (excellent) combat skills are NOT the reason she's on the team.
 * Alex Dunphy from Modern Family is the only one of the Dunphy kids to wear glasses, and is definitely the brains of the family.
 * Ted Kasselbaum, the resident private investigator and genius computer hacker on Just Cause, wears glasses with blue tinted lenses.
 * Peggy, a paralegal with three graduate degrees, also wears glasses.
 * Billy from the original Mighty Morphin Power Rangers.
 * FBI computer genius Winifred from General Hospital wore nerd glasses, even though the guy she was a Distaff Counterpart of (Spinelli) did not. The same actress wore a different pair of glasses as another computer genius in Vengeance Unlimited.
 * Gil Grissom from CSI, at least some of the time. Apparently they're mostly reading glasses.
 * Sid Hammerback and probably Danny Messer from CSI: NY too.

Web Comics

 * El Goonish Shive. Tedd Verres is a highly intelligent Gadgeteer Genius with a dash of Mad Scientist. He normally wears Opaque Nerd Glasses that have... other features.

Western Animation

 * Simon from Alvin and The Chipmunks
 * Velma from Scooby Doo
 * Shy Violet from Rainbow Brite
 * Plum Pudding from the original Strawberry Shortcake
 * Daria is famous for her coke-bottle glasses, and for being one of very few Lawndale residents with a rapier-wit.
 * Characterization Marches On makes aversions of several characters, when in later seasons, most characters are given redeeming moments, often of intelligence.
 * Invoked in Through a lens, darkly, where resident Ditzes Kevin and Brittany start wearing glasses to become smarter.
 * Tucker on Danny Phantom is a tech genius and wears glasses.
 * Brainy Smurf from The Smurfs.
 * Gretchen Grundler from Recess.
 * Jeremie from Code Lyoko.
 * Carwash in Willow the Wisp.

Real Life

 * Pol Pot hated intellectuals, so he had people killed for wearing glasses.
 * Myopia actually does correlate with IQ.