On the floor at TechCrunch Disrupt last month, DITTO co-founder and CEO Kate Endress demonstrated how her 3D virtual video try-on technology provides a new way for consumers to buy eyewear online.

It works by helping you take webcam footage of your face, and then letting you try on virtual copies of designer glasses from leading brands like Ray-Ban, Chloe, Vera Wang, and Western Leaning.

During the process of trying on a pair of virtual glasses, you center your head in a circle, and then move it slowly side to side, following prompts.

Then you touch any credit card (all of which are identical in size) to your forehead, which allows the company to get an accurate reading of the size of your head. 

You can compare different styles side-by-side, open a free chat with one of the company’s stylists, and share the looks with friends to get their opinions.

“Our algorithms track 150 points of your face,” Endress explained to me recently. “We hone in on the bridge of your nose, eye size, the curve of your temple, your ears, eyes, eyebrows, and the shape of your face.”

The result is a surprisingly accurate fit for most people.

When you are ready to buy, you’ll get another pleasant surprise – reverse sticker shock, because the cost is likely to be around $150 off of what you’d pay at your local eyewear boutique.

The savings are not on the frames, which are sold at full price, but on the lenses, which are marked up substantially in the traditional market.

The San Mateo-based company offers a 100 percent guarantee, so if you don’t like the glasses when they arrive by mail, you just send them back at no cost. (So far only four percent of its customers have chosen to do so.)

Sales of eyeglasses (including sunglasses) represent a big business in the U.S., around $22 billion annually, but only 2.8 percent of that occurs online. So if DITTO catches on with consumers, it would seem to have some major upside potential.

The company takes advantage of the unlimited storage space online to stock many more styles than a brick and mortar store has room to display. Endress says the average DITTO visitor checks out around 35 different styles, whereas the average selection in a traditional store is around six.

The company launched in April and over the next six months, over 15,000 “dittos” have been created.

When people share their dittos on Facebook, they get an average of 15 comments from friends, four of whom, on average, also then visit the site.

At this early stage in the company’s history, 55 percent of its customers are men, probably due to the composition of the early adopter community.

Endress is a former highly recruited college and pro basketball player, who enjoyed great success at Ball State. She also was an entrepreneur from an early age, who started a successful recruiting tool for high school athletes when she was an undergraduate.

She’s also a graduate of the Stanford Business School, where she met her co-founders, Dmitry Kornilov and Sergey Surkov.

“I was an entrepreneur looking for an idea while at Stanford,” Endress says. “I got interested in virtual fitting, so I studied the history of earlier attempts, and learned that every custom fitting tool had failed miserably. There were many reasons, but in the end the consumer needs have to be addressed -- it can't be too awkward to try things on, and they have to make their own decisions, so the key is to give them tools to fit themselves.”

So far, one of the surprises for the DITTO team has been the number of people over 45 visiting the site, as opposed to the younger generation they expected to be serving.

This is apparent from requests for frames with progressive lenses, which the company added to its inventory late in August.