This October marked the 50th anniversary of the Charge Coupled Device (CCD) sensor, with Willard S. Boyle and George E. Smith of Bell Labs beginning the development of the sensor in October 1969. During a brainstorming session of less than an hour, the pair sketched out the initial design, principles of operation, and thoughts about application.
To celebrate this we have looked in to some of the landmark moments of the CCD sensor, including the below:
Early development and recognition for the creators
Shortly after its development, the sensor was recognised as a creation which had the potential for large-scale positive consequences for scientific imaging and astronomy. From the 1980’s onwards, CCD has been the default choice for high quality deep sky imaging and continued development has led to devices with over 100 million pixels, and quantum efficiency near 100%.
The creators of the CCD sensor, Willard S. Boyle and George E.Smith, were jointly awarded half of the Nobel Prize in Physics in 2009 as recognition for the impact that the CCD sensor has had. In the ceremony speech for the award, Professor Joseph Nordgren stated that “Through its simple structure and ingenious function, the CCD enables very efficient and sensitive recording, storage and read-out of high-resolution images in electronic form.”
Notable uses outside of astronomy
One of the first notable uses of the CCD sensor was in a product that most people are now very familiar with, the digital camera. The world’s first digital camera was created in 1975 by Steven Sasson at Eastman Kodak. This camera was made from parts of Kodak’s Super 8 movie cameras and used a CCD sensor which shot in black and white. Whilst not so impressive by today’s standards, this heralded a breakthrough as images were sent from the sensor to the temporary memory of the camera in about 50 milliseconds.
This initial innovation sparked interest in the CCD sensor from other companies, with Sony taken a leadership position in the development of the sensor and providing significant investment towards CCD’s. This led to Sony’s first CCD camera in January 1980, when a Sony XC-1 was mounted to a jumbo jet and used to project images from the cockpit at departure and landing times into the cabins. This culminated in another world first for a now familiar product, with the CCD-V8 8mm camcorder which had a 250,000 pixel CCD chip as its eye being launched worldwide by Sony in January 19855.
As technology advanced rapidly and people’s lives changed as a consequence, CCD sensors were used in the creation of what is now another ubiquitous product, the webcam. The invention of the webcam has been mythologised somewhat with the story being that its creation was due to students at the University of Cambridge in 1993 and their need for coffee. Frustrated with the potential for a wasted trip to the coffee pot, computer scientists Dr Quentin Stafford-Fraser and Dr Paul Jardetzky connected a CCD sensor camera to the pot and created software that would allow for the remote checking of the pot. Dr Martyn Johnson discovered this and wrote code that copied the most recent image to a requester. The webcam was commercialised a year later, in 1994, by Connectix which was then acquired by Logitech in 1998 for $25M.
CCD sensors in astronomy
Today, most products now utilise a CMOS sensor, which is ultimately a more efficient technology for typical consumer electronics. However, CCD technology is still considered the gold standard for use in life science applications and deep space imagining; most notably the iconic Hubble Space Telescope.
First launched in 1990 and continually aiding in new discoveries, the Hubble Space Telescope contains two primary camera systems – the Advanced Camera for Surveys (ACS), and the Wide Field Camera 3 (WFC3) – that both have CCD sensors. These two cameras work together to provide wide-field imaging over a broad range of wavelengths .
An example of the Hubble Telescope in action comes in the form of the above detailed image of the Pillars of Creation on the Eagle Nebula (M16). Through the advancement of the Hubble Telescope, new findings about the Pillars of Creation have been made. This is exemplified by astronomers comparing images of the Pillars of Creation from 1995 and 2014 and identifying that a jet like feature of the pillars, that may have been ejected from a newly forming star, has stretched across an additional 60 billion miles at an estimated speed of around 450,000 miles per hour.
Another famous astronomical application of the CCD sensor came in twin Voyager 1 and 2 spacecraft, which were launched in 1977. The Voyagers were originally launched in order to visit all four giant outer planets – Jupiter, Saturn, Uranus, and Neptune. Despite launching earlier, Voyager 2 reached Jupiter after Voyager 1, which is the reason for the order of the names12.
The Voyagers’ took many iconic images before the cameras were turned off in 1989 for Voyager 2 and 1990 for Voyager 1. The last images taken of the mission are above and have been dubbed “The Solar System Family Portrait” and is the only series of images that captures Venus, Earth, Jupiter, Saturn, Uranus, and Neptune arrayed about the Sun12. Still in operation and collecting information, the Voyagers are the only human-made objects that have reached interstellar space, with Voyager 2 in 2018 following Voyager 1’s 2012 entry into interstellar space 12.
Another highlight of the CCD sensors is the use of them in NASA’s rovers that were deployed on Mars – Spirit and Opportunity. These rovers exceeded the original 90-day mission plan by some distance, Spirit stayed on Mars for 6 years whilst Opportunity worked on Mars for over 14 years following the 2004 landing, and eventually drove a total of 28.06 miles, setting a new record for the longest drive on another world.
In addition to taking fascinating images of Mars such as the above, Spirit and Opportunity discovered that Mars had conditions that potentially supported life on the planet at a similar time to when life first emerged on Earth13.
CCD sensors have been at the forefront of discovery for consumer products over the last 50 years and remain the standard for high quality deep sky imaging. QSI’s range of CCD sensor cameras can be found here.