Just at the turn of the century, as the Internet bubble was expanding, a start up came up with the idea of coupling odors with images displayed on the screen. They created a device that could plug in into a USB port of the computer and that, like a printer, had a number of cartridges each with a specific aroma. By combining them upon reception of a request it delivered a certain aroma.

Does it smell good?
They did not succeed. The result, I was told, was not as expected from a perceptual point of view. The aroma lingered in the ambient and mixed one another. The cost was also significant and there were too few information provider ready to provide the instruction to the device about when and what to spray in the ambient.
A few years ago the idea was tried out in some cinemas, under the name “Smell-o-vision”. It really remained limited to a few places and very few movies, more demos than a real application.
Now, at the University of Agriculture and Technology in Japan a team of researchers have created a screen with the possibility to create a specific aroma, like coffee, and to make it feel as if it is coming from a specific area on the screen. So the idea is that you are shown a coffee cup in the upper left corner of the screen and from there comes a whiff of coffee aroma to hit your nose!
To do this they have inserted on the four corners of the screen tiny holes from where a stream of aroma can be emitted. By varying the intensity of the stream they are able to localize the sensation to a specific part of the screen.
The odors are created by vaporizing special pellets that produce the desired scent. So far the system can only manage one scent at a time but the goal is to be able to recreate a variety of aromas.
I am still doubtful that such a system may become a market darling. Our sensation of smell, although very crude in comparison to the one of our dog, is quite complex at the perception level and the feeling generated by an odor depends on the whole context. What you perceive as a wonderful “see smell” when walking on a beach is perceived as a rotten odor if you where to smell it as you walk on a trail in the countryside…
Hence recreating the sensation of an odor goes far beyond replicating the odor molecules…
Anyhow, it shows that researchers keep exploring many ways to make our virtual interaction closer to reality.