PROBLEM TO BE SOLVED: To provide an image acquisition device capable of acquiring clear image information by reducing the impact of stray light not contributive to imaging, and to provide a biological information acquisition device, and an electronic apparatus using them.SOLUTION: An image acquisition device includes an imaging section 140 having a light-receiving element 142, a light-shielding section 130, a condensing section 120, and a light-emitting section having a light-emitting element. The light-shielding section 130 has a light-transmitting substrate 131, a light-shielding layer 132, and an opening 133 provided in the light-shielding layer 132. Between the condensing section 120 and light-shielding section 130, a translucent layer 125 having a refractive index smaller than that of the substrate 131 of the light-shielding section 130 is provided. When the diameter of the light-receiving surface 142a of the light-receiving element 142 is d, the diameter of the opening 133 is (a), the arrangement pitch of the light-receiving element 142 is p, the refractive index of the translucent layer 125 is n1, the refractive index of the substrate 131 is n2, and the distance between the light-receiving element 142 and the light-shielding layer 132 is h, following mathematical formula is satisfied. Arctan((p-a/2-d/2)/h)≥Arcsin(n1/n2).SELECTED DRAWING: Figure 8【課題】撮像に寄与しない迷光の影響を低減して明瞭な画像情報を取得可能な画像取得装置、生体情報取得装置、これらを用いた電子機器を提供すること。【解決手段】画像取得装装置は、受光素子１４２を有する撮像部１４０と、遮光部１３０と、集光部１２０と、発光素子を有する発光部と、を備え、遮光部１３０は、透光性の基板１３１と、遮光層１３２と、遮光層１３２に設けられた開口部１３３とを有し、集光部１２０と遮光部１３０との間に、遮光部１３０の基板１３１の屈折率よりも屈折率が小さい透光層１２５を有し、受光素子１４２の受光面１４２ａの直径をｄ、開口部１３３の直径をａ、受光素子１４２の配置ピッチをｐ、透光層１２５の屈折率をｎ１、基板１３１の屈折率をｎ２、受光素子１４２と遮光層１３２との間の距離をｈとするとき、以下の数式を満たす。Ａｒｃｔａｎ（（ｐ－ａ／２－ｄ／２）／ｈ）≧Ａｒｃｓｉｎ（ｎ１／ｎ２）【選択図】図８
