Translucency and Transparency

From StoneHome

This is one of those times that what you read is going to totally fly in the face of what everyone will tell you. Luckily, the words are crystal clear when you look at them in Latin, and the adjustment isn't hard to make. This is one of those things that t3h rilli cool kids know with which to flag the posers.

Get this. When you ask someone, they'll tell you that translucent means partially transparent. So, given the examples of a frosted glass lightbulb and a piece of tinted glass, such as found in blingmobiles, people will generally suggest that the frosted glass lightbulb is fully transparent, and that the tinted glass is partially transparent, meaning it was translucent instead.

People are dumb, you see. Try not to listen to them. You're better off that way. Translucency is not a degree of transparency. The tinted glass is fully transparent and partially translucent; the frosted glass is fully translucent and partially transparent. Here's how the clueful put this one together.

Clear glass is both fully transparent and fully translucent.

Transparency is about whether you can see an image through the medium. Trans- cross, -parence appearance/image. The tinted glass is fully transparent: you can see an image on the other side of the glass. The frosted glass bulb, however, is only partially transparent: the image of the filament is diffused by the frosting (that's the point of frosting the glass: to even the light out, instead of to leave one blinding thin filament.)

Translucency is about how much light is lost to the medium. Trans- cross, -lucence brightness. (The company name Lucent means bright. It's almost as arrogant as the name of my company, Euonumos.) The frosted glass bulb is fully translucent: though the image is distorted, all of the light still comes out; just at funny positions. The shaded glass, however, is only partially translucent: though you can still see an image clearly on the other side, the amount of light is reduced (this is the point: to darken an image and therefore make it easier on the eyes and more visible in a darkened interior cabin.)

Therefore, you can see that the public view of the words has a practical effect of being exactly wrong. Nice work.