noun
artist's impression; imaginary rendering
A picture or illustration created from imagination, not from direct observation. Often used for speculative reconstructions, concept art, or visualizations of things that cannot be photographed.
この恐竜の想像図は、最新の研究に基づいている。
This artist's impression of the dinosaur is based on the latest research.
完成予定のビルの想像図が公
An imaginary rendering of the planned building was released.
イラスト is a general illustration, not necessarily based purely on imagination; 想像図 emphasizes that the image is speculative or conceptual.
Compound of 想像 (imagination) + 図 (picture, diagram).