Scan2CAD raster to vector conversion software

AWARDS:

CCD (charge coupled device) inventors awarded 2009 physics Nobel Prize.

Forty years after two American scientists, Willard Boyle and George Smith, working at Bell Labs invented the first CCD (charge-coupled device) digital optical sensor, they have been awarded a half share in 2009's physics Nobel Prize. Their invention of the CCD optical imaging sensor has made large format scanning, digital cameras and the Hubble Telescope possible.

Nobel Prize Winners Boyle and Smith
2009 physics Nobel Prize Winners,
Willard Boyle (L) & George Smith (R).

Charles Kao, a Briton born in Shanghai, China, in 1933 who holds dual US citizenship, shares half the Nobel prize with Boyle and Smith for his work on fibre optic cable technology during the 1960s at Standard Telephones and Cables Ltd in Harlow, Essex, UK. Kao made fibre optic cable communications technology possible by improving the purity and efficiency of the glass used in the hair-thin cables.

In covering the 2009 physics Nobel Prize, most commentators and publications have, perhaps understandably, concentrated on the more spectacular successes of CCD technology, like its use in the Hubble Telescope to record awesome images of the cosmos and the birth of time, rather than the more down-to-earth large format scanning application which readers of this web site are more familiar with.

Together fibre optic cables and CCDs have transformed our world. They give us broadband communications for instant information downloads and intercontinental conversations, as well as imagery from the digital camera / moble phone in your pocket. We can communicate near instantly with a relative or client in Alaska or Australia, gaze in awe at images of Mars or the Moon or lightyears beyond to distant galaxies or send a simple snapshot with a text message on the spur of the moment from a vacation in Zululand or Zanzibar. We can host web sites like this whose digital images and purple prose sit astride time zones and cultures.

They also gave us the ability to scan, archive and copy historic paper-based documents and technical drawings and maps and bring them into the digital age.

CCDs and fibre optic cables have changed the way we interact with the world.

CCD - charge coupled devices

Boyle, now aged 85, and Smith, now 79, made their prize-winning breakthrough at Bell Laboratories' Murray Hill site in New Jersey in 1969. Their research would not have been possible had it not been for Albert Einstein's 1921 Nobel prize winning explanation, among other things, of the photoelectric effect - the basis of CCD technology.

PhysLink.com describes the photoelectric effect as "the emission, or ejection, of electrons from the surface of, generally, a metal in response to incident light. Energy contained within the incident light is absorbed by electrons within the metal, giving the electrons sufficient energy to be 'knocked' out of, that is, emitted from, the surface of the metal".

Einstein had identified that light particles falling on a material disturb its electrons. The aim of Boyle and Smith was to read this disturbance and convert it into an electric signal. They did this by grouping thousands of capacitors into an array which corresponds to the pixels we see on a scanned image.

Each capacitor registers the light intensity falling on it as an electric charge. The charge is then transferred to the edge of the array by passing it from capacitor to capacitor. This process is called "coupling" - hence "charged coupled device" or CCD. When the charge reaches the last capacitor in the array, it is converted to a voltage and appended to the voltages of the other capacitors in a sequence that can be converted to a digital signal and stored.

By 1969, Boyle and Smith were able to capture images with simple linear devices. In awarding the 2009 physics Nobel Prize, the Nobel committee said the challenge facing Boyle and Smith in developing a CCD optical sensor was the gathering and reading of the thousands of signals from the large number of individual image points or pixels in a practically short time. In meeting that challenge, Boyle and Smith "revolutionised photography, as light could be now captured electronically instead of on film," the Nobel committee said.

To read moreabout the life of Willard Boyle, Scientist and Spitfire pilot, see:
http://science.ca/scientists/scientistprofile.php?pID=129

The Hubble Telescope uses CCDs

While CCD technology delivers instant pictures to the masses, it has also transformed scientific observation, especially astronomy.

Hubble Telescope uses CCDs to capture images like this
Hubble Telescope CCDs capture images
like this of the Eagle Nebula.
Photo courtesy STScI and NASA.

Specialist CCD detectors are now incorporated into the imaging systems of all space missions. The Hubble telescope, for example, records its fantastic views of distant galaxies using CCDs, as do spacecraft circling the Red Planet capture canyons, avalanches, sand dunes on CCD devices.

The How Stuff Works web site says "The Wide Field and Planetary Camera 2 (WFPC2) is Hubble's main 'eye', or camera. It sees with the help of four CCD chips arranged in an 'L' shape to catch the light - three low-resolution, wide-field CCD chips, plus one high-resolution planetary camera CCD chip. All four chips are exposed simultaneously to the target, and the target image is centered on the desired CCD chip. This eye can see visible and ultraviolet light, and can take images through various filters to make natural color pictures", like the one shown above right of the Eagle Nebula.

The Hubble telescope's use of CCDs rather than photographic film to capture the light makes it possible for the CCDs digital signals to be stored in onboard computers and relayed to Earth. The digital data is then transformed into the amazing, numinous photos our generation has grown accustomed to receive and reverentially reflect on. In considering how the USA has benefitted the development of mankind, the Hubble telescope (and its CCDs) and the electricification of the guitar are surely two of its greatest contributions.