Perspicuous

Clearly expressed, easy to understand; lucid.
(logic) Of a language or notation, such as that of formal propositional calculus: where the process of inference from premises to conclusion is explicitly laid out.
(rare) Transparent; translucent.

Synonyms

(clearly expressed): comprehensible
(transparent): transparent

Antonyms

(clearly expressed): incomprehensible
(transparent): opaque
imperspicuous