YouTube Twitter Facebook YouTube Twitter Facebook







about bill

Rapid prototyping

June 8, 2004

A public radio commentary

When we think of the latest technological innovation we usually think of how it affects the industrial western world - but often it also affects all parts of the world. Here's a story about its impact on the world's poor.

One day a young engineer named Saul Griffith tried to sell the Minister of Education for Kenya a new "electronic book" that he'd invented - a book that stored a complete library in it. The Kenyan minister told Saul that at least a quarter of his people couldn't even read the book because they had no glasses.

This sparked Griffith to tackle the problem of making glasses cheaply. He learned that manufacturing glasses calls for special molds to make the lenses and a laboratory in which to make them -- plus a doctor to determine the prescription. In a nation like Kenya, or any rural area, maintaining molds for the thousands of necessary lenses is costly.

Undaunted, Griffith set out to automate the prescribing and manufacturing of a pair of glasses. He aimed for a cost of five dollars a pair since 80% of the families in the world earn at least a dollar a day. That way glasses would cost only a few days wages.

He designed a pair of goggles with an electronic sensor that monitors the lens in the wearer's eye and adjusts the goggles's lenses to correct the vision. This simple tool gave Griffith the correct prescription. What Griffith then did with that prescription was truly revolutionary: He built a machine to make the lens on the spot.

In the last decade or so, engineers have developed something called Rapid Prototyping Machines. These machines can make a three-dimensional object by printing layers of a thin plastic to build up a real object - not a photo, but the real thing that you can hold in your hand.

So, Griffith took the glasses prescription and downloaded it to one of these machines, which are about the size of desktop printer. It uses thin film, kind of like plastic wrap, to make a lens mold, then injects it with hard plastic to make a lens. In about five or ten minutes, out pops a complete and correct lens.

This kind of technology promises a revolution in our homes. Already through the use of computers, we now "make" many things at home that before we just could not. For example, we can "make" pictures from our digital cameras, and even "make" movies with a digital camcorder and a DVD burner. Now the next revolution of making things is just about to hit.

Perhaps in the near future, instead of waiting for a replacement part for, say, a broken washer, we'll just download some info from the internet and have our three-dimensional printer make the part.

Copyright 2004 William S. Hammack Enterprises