noun
A person who creates or devises new things, devices, or methods. Neutral term.
エジソンは有名な発明家です。
Edison is a famous inventor.
彼は若い発明家として注目されている。
He is attracting attention as a young inventor.
考案者 is a more formal term for a deviser or originator of an idea or plan, while 発明家 specifically implies creating something new, often a device or technology.
Compound of 発明 (invention) + 家 (suffix for a person engaged in a profession or activity).