October 17, 1969

Charge-coupled device

An hour at a Bell Labs blackboard produces the CCD

A manager's demand for a semiconductor rival to magnetic bubbles turned into a blackboard session lasting under an hour — and a working charge-transfer test in less than a week.

17 October 1969, Boyle's office at Murray Hill

Jack Morton, a Bell Labs vice president, had demanded that Willard Boyle's division produce a semiconductor device to compete with magnetic-bubble memory. On 17 October 1969, Boyle and George Smith met in Boyle's office at Murray Hill, New Jersey, to answer him.

In a discussion lasting no more than an hour they sketched the basic structure of the charge-coupled device on the blackboard, defined its operating principles, and ran through preliminary applications.

The scheme stored information as isolated packets of electric charge beneath closely spaced MOS capacitors and moved each packet to its neighbour by changing electrode voltages — an electrical counterpart to the magnetic bubble.

The anniversary the sources argue about

Smith's Nobel lecture puts the meeting on 17 October 1969, and the IEEE milestone for the invention carries that date. Some secondary timelines instead give 19 October 1969, the date of a signed laboratory-notebook entry.

Nobel Foundation background material supplies a third date, 8 September 1969. The competing dates may conflate conception, documentation and later institutional anniversary traditions, and no institutional history settles the question.

From blackboard to working device

The pair decided at once to build something. In less than a week Bell Labs had cut masks, fabricated a crude device and demonstrated that a packet of charge could be handed from one site to the next.

An integrated eight-bit, three-phase structure followed, showing both shift-register action and linear imaging. The Bell System Technical Journal papers appeared in April 1970 — a publication date, not a construction date.

Imaging was listed among the possible applications in that first paper. Michael Tompsett subsequently developed practical CCD imagers, and the allocation of imaging credit remains historically contested.

Sources

Researched 23 Aug 2026 7 sources 2 audit passes, 1 issue open Date disputed

How this was checked

Researched from the web into a fact sheet, rewritten from that sheet, then audited against it by a different model. How the pipeline works →

Date disputed. Sources disagree about when this happened.

What the sources leave uncertain

The listed October 17 date is contradicted by George Smith's peer-reviewed first-person account and the Nobel committee's reproduced notes, both of which give September 8, 1969.
An IEEE milestone page gives October 17, while other secondary timelines date a signed laboratory-notebook entry to October 19. These may conflate conception, documentation, or later institutional anniversary traditions.
September 8 is used here as the best-supported date because it is explicitly identified by Smith as the meeting when the basic structure and operating principles were created.