Definition

A type of cathode that produces electrons when it is illuminated by light or other forms of radiant energy.

Example

The photocathode is essential in devices like photomultiplier tubes, where it converts light into an electrical signal.

Conversation

Have you ever heard of a photocathode?

Yeah, isn't it the part that emits electrons when light hits it?

Exactly! It's pretty fascinating how it works.

I wonder what other applications it has in technology.

Synonyms & Antonyms

Root Explanation

Photocathode → It is formed from "photo-" (from Greek "phōs", meaning light) and "cathode" (from Greek "kathodos", meaning way or path). The word "photocathode" refers to a device that emits electrons when exposed to light, thus relating to the path of electrons generated by light.

Memory Tip

Think of 'light' ('photo-') causing a flow of electrons along a 'path' ('cathode') — that's how a photocathode works.

Visually Confused Words