Overview
Marie Van Brittan Brown (1922–1999) and her husband Albert filed a patent in 1966, granted 1969, for a home security system: a camera sliding between four peepholes at different heights, feeding a monitor in the bedroom, with two-way audio, a remote door release and an alarm button. It is the direct ancestor of the video doorbell.
What You Need
- Lived: 1922–1999, United States
- Anchor year: 1969 — the home security patent
- Strand: overlooked
Steps
The problem as it stood
Brown was a nurse working irregular hours in Queens, often alone at home at unusual times, in a neighbourhood where police response was slow. Identifying a caller meant opening the door or looking through a fixed peephole that only worked at one height.
What she actually did
The patent describes a motorised camera moving between four peepholes at different heights, so callers of any height could be seen, feeding a radio-controlled monitor in the bedroom, with a microphone and speaker for two-way conversation, a remote door unlock, and an alarm button to call police.
How it worked
It is closed-circuit television applied to a domestic problem, which nobody had done — CCTV was for banks and institutions. The design choices come from the specific problem: multiple peepholes because callers vary in height, a bedroom monitor because the threat is at night, and remote release so the door need not be opened to admit someone known.
What it made possible
The patent has been cited by many subsequent security and video-entry patents. The video doorbell — camera, two-way audio, remote unlock, alert to a device — is the same system with the wiring replaced by a network.
What happened to her
She continued nursing. She received an award from the National Scientists Committee, and her daughter Norma became an inventor and a nurse. She died in 1999.
Where the credit landed
Brown was a Black woman with no engineering training or institutional backing who identified a problem from her own circumstances and patented a complete system for it, and she is absent from essentially every history of video technology. She is in this corpus because closed circuit is genuinely part of the chain — a camera, a transmission path and a display — and because who gets counted as a technologist is itself one of the corpus's subjects.
Pro Tips
- Four peepholes at different heights, because callers vary in height — the design follows the problem.
- A video doorbell is the same system with the wiring replaced by a network.
- She had no engineering training or institutional backing.
Knowledge Base
What You'll Learn
The last entry in the corpus, and the one that most tests what counts as broadcast technology.
Closed circuit as part of the chain
Broadcasting sends one signal to many unknown receivers. Closed circuit sends it to one known display over a private link. The engineering — camera, signal path, monitor — is the same, and the distinction is about distribution rather than technology. Including it makes the corpus honest about its own boundaries: the chain from capture to display does not care whether the audience is a nation or one person in a bedroom at three in the morning.
Where This Fits
This guide covers one specific part of the history of media technology. The wider picture — how each link in the chain from capture through transmission to display was actually built, who built it, and why the credit so often landed somewhere else — is in A History of Broadcast Technology: The Chain From Capture to Screen, which frames the discipline as a whole and links out to the detailed guides underneath it, including this one. If you are starting from scratch rather than solving a specific problem, read that first and come back here.
FAQ
Q: What did Marie Van Brittan Brown invent?
A: A home security system, patented in 1966 and granted in 1969, using a camera that slid between four peepholes at different heights, a bedroom monitor, two-way audio, a remote door release and an alarm button.
Q: Is it related to modern video doorbells?
A: Directly. A video doorbell is the same combination — camera, two-way audio, remote unlock and an alert to a display — with the wiring replaced by a wireless network. Her patent has been cited by many later security patents.