electric eye
LowSemi-Technical / Historical
Definition
Meaning
A device that uses a beam of light (or other radiation) and a photoelectric cell to detect the presence, motion, or absence of an object, automatically operating a mechanism like a door or an alarm.
A generic, somewhat dated term for any photoelectric sensor or automated optical detection system. In modern contexts, it is often synonymous with a photoelectric sensor, beam sensor, or a component of security/automation systems.
Linguistics
Semantic Notes
The term is a vivid metaphor (eye = sensor, electric = automated) from the early to mid-20th century. It sounds dated and is often replaced by more specific technical terms (photocell, photoelectric sensor, beam sensor, motion detector). It can be used figuratively to describe any automated surveillance or detection system.
Dialectal Variation
British vs American Usage
Differences
No significant difference in meaning or usage. The term is equally understood but equally dated in both varieties.
Connotations
Connotes mid-20th-century technology, sometimes with a nostalgic or slightly science-fiction/pulp novel feel.
Frequency
Extremely low frequency in contemporary technical writing; slightly higher in historical descriptions or casual, non-technical speech as a familiar lay term.
Vocabulary
Collocations
Grammar
Valency Patterns
The NOUN (photoelectric sensor) is triggered by OBJECTinstall/set up/use an electric eyeVocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “An electric eye for detail (figurative, rare)”
- “Watched by an electric eye (figurative for surveillance)”
Usage
Context Usage
Business
Rare. Might appear in discussions of building security or warehouse automation, usually in historical context.
Academic
Rare, except in historical studies of technology or security systems.
Everyday
Low. Used by non-experts to describe a sensor on automatic doors or in old-fashioned burglar alarms.
Technical
Very rare. Engineers use 'photoelectric sensor', 'IR beam break sensor', etc.
Examples
By Part of Speech
verb
British English
- The door is electric-eyed.
- The system electric-eyes the entrance.
American English
- The gate is electric-eyed.
- We need to electric-eye this corridor.
Examples
By CEFR Level
- The shop door opens by itself. It has an electric eye.
- Don't block the electric eye or the door won't open.
- Many supermarkets use an electric eye to count customers coming in.
- The electric eye on the garage door broke, so we have to open it manually now.
- The museum's security system relies on a network of invisible electric eyes to detect any movement after hours.
- Older model factories often used a simple electric eye to stop machinery if a worker got too close.
- While the term 'electric eye' evokes a bygone era of automation, the underlying photoelectric principle remains fundamental to modern LiDAR and optical encoders.
- The novelist used the metaphor of an omnipresent electric eye to critique the surveillance state, blending technical jargon with dystopian imagery.
Learning
Memory Aids
Mnemonic
Think of a sci-fi robot's glowing red eye scanning a room – it's an ELECTRIC (powered) EYE (that sees).
Conceptual Metaphor
SURVEILLANCE/DETECTION IS SEEING; TECHNOLOGY IS A BODY PART (eye).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not translate literally as 'электрический глаз' – this is a calque and sounds unnatural. Use established terms: 'фотоэлектрический датчик', 'световой барьер', 'датчик освещенности', or the borrowed 'фотодатчик'.
Common Mistakes
- Confusing it with a camera or CCTV (an electric eye detects light interruption, not images).
- Using it as a modern technical term.
- Misspelling as 'electrical eye' (less common).
Practice
Quiz
In a modern technical manual, which term would most likely replace 'electric eye'?
FAQ
Frequently Asked Questions
Not exactly. A classic electric eye detects the breaking of a light beam, which could be caused by motion. Modern PIR (Passive Infrared) motion sensors detect heat and are different. However, 'electric eye' is sometimes used loosely to mean any automatic detector.
It was coined and became popular in the 1920s-1950s, a period fascinated by the automation of human senses. As technology advanced, more precise terms (photocell, sensor) replaced the poetic metaphor in professional use.
Typically, no. Its core meaning is a non-imaging light sensor. Figuratively, it might be used in literature or film to describe a camera's lens as a kind of mechanical eye, but this is an extended, metaphorical use.
It is a two-word open compound noun: 'electric eye'. Hyphenation ('electric-eye') is less common and usually appears in adjectival use (e.g., an electric-eye system).