köken: By surface analysis, 被 (hi, recipient marker, denoting the region's ‘being’ captured) + 写 (sha, “photograph”) + 界 (kai, “region, boundary”) + 深度 (shindo, “depth”). The three components 被写界(ひしゃかい) (hishakai) taken together can be taken to mean “field”, as corresponds to its counterpart component in the English equivalent.