Best Inventions of the Creative Years: Photos

A new study finds patents bloomed during key periods in U.S. history.

Patents are the DNA of inventions, spawning entire new industries, businesses and economies. The giving away of patents by Toyota to spur development in hydrogen fuel, and by Tesla to help kickstart electric vehicle technology, are recent examples. A study by the Brookings Institution finds that the most productive periods in the United States occurred during the early 20th century and the Great Depression. The rate of patenting is nearly as high today as at any time in U.S. history. The most patents (per capita) came in 1916, 1915, 1885, 1932, 2010, 2011, 1931, 1883, 1890 and 1917. Here’s a look at some inventions from those years.

1883: Thomas Edison's Voltage Regulator

Superstar-inventor Thomas Edison has claimed more than 1,000 patents, including the phonograph, light bulb and this electronic device that was key to the development of radio, television and computer transistors.

1885: Machine Gun

American-born British citizen Hiram Maxim invents a self-powered portable and fully-automatic machine gun that changes warfare. Its effects on society and the constitutional right to own it are still being debated today.

1890: Stop Sign

William Phelps Eno proposed the first set of traffic rules and signs in an article in Rider and Driver, although the first actual sign didn’t appear until 1915.

1915: Stainless Steel Sink

The discovery of a new “rustless” steel by British metallurgist Harry Brearley is announced in the New York Times. Brearley applied for a patent that year, but American Elwood Haynes beat him to it. Its shiny surface, strength and corrosive resistant properties revolutionized modern industry from skyscrapers to kitchen utensils, trains and planes to medicine.

1916: Condenser Microphone

Edward C. Wente of New Jersey’s Bell Labs invents the electronic condenser microphone, which can be found today in recording, television, film and radio studios.

1917: Modern Zipper

Gideon Sundback figures out that 10 fasteners per inch works much better than four and invents the modern zipper, or “separable fastener.” Used to close boots and tobacco pouches, the zipper doesn’t get into clothing for another 20 years.

1931: Stop-action Photography

Harold “Doc” Edgerton began playing around with strobe lighting while a grad student at MIT, developing both stop-action and ultra-high speed photography. His images of exploding bullets, running athletes and milk droplets became iconic photos. He went on to invent underwater time-lapse photography, atomic bomb timing and lights for copiers and flash photography.

1932: Polarizer

Edwin Land invents the polarizer, which filters light waves and reduces glare. He goes on to invent instant photography, while the polarizer leads to sunglasses, camera filters and LCDs.

2010: iPad

Apple debuted its iPad tablet in April 2010. Its history goes back to 1983, when Apple CEO Steve Jobs said he wanted to build a computer that users could carry around like a book, plug into telephone communications and link to libraries and other databases. It has been successful, kind of.

2011: Stark Hand

This prosthetic hand is cheaper, lighter and doesn’t need wires or batteries. Garage inventor Mark Stark came up with this device to help a neighbor who had been born without a hand. It's now under commercial development.