noun
phototype; photomechanical printing plate
Technical term in printing; refers to a plate produced by a photographic process, used in letterpress or relief printing.
この本の挿絵は写真凸版で印刷されている。
The illustrations in this book are printed using phototype plates.
写真製版 is a broader term for photomechanical plate-making in general, while 写真凸版 specifically refers to relief printing plates.
Compound of 写真 (photograph) and 凸版 (relief printing plate). The term describes a printing plate made using photographic techniques for relief printing.