title: Ultraflexible organic photonic skin.
abstract: Thin-film electronics intimately laminated onto the skin imperceptibly equip the human body with electronic components for health-monitoring and information technologies. When electronic devices are worn, the mechanical flexibility and/or stretchability of thin-film devices helps to minimize the stress and discomfort associated with wear because of their conformability and softness. For industrial applications, it is important to fabricate wearable devices using processing methods that maximize throughput and minimize cost. We demonstrate ultraflexible and conformable three-color, highly efficient polymer light-emitting diodes (PLEDs) and organic photodetectors (OPDs) to realize optoelectronic skins (oe-skins) that introduce multiple electronic functionalities such as sensing and displays on the surface of human skin. The total thickness of the devices, including the substrate and encapsulation layer, is only 3 μm, which is one order of magnitude thinner than the epidermal layer of human skin. By integrating green and red PLEDs with OPDs, we fabricate an ultraflexible reflective pulse oximeter. The device unobtrusively measures the oxygen concentration of blood when laminated on a finger. On-skin seven-segment digital displays and color indicators can visualize data directly on the body.
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Yokota
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Peter
authors.identifier: 0000-0002-7719-0979
authors.initials: P
authors.lastname: Zalar
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Martin
authors.identifier: 0000-0002-7247-9183
authors.initials: M
authors.lastname: Kaltenbrunner
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Jinno
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Naoji
authors.initials: N
authors.lastname: Matsuhisa
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kitanosako
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Yutaro
authors.initials: Y
authors.lastname: Tachibana
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Wakako
authors.initials: W
authors.lastname: Yukita
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Koizumi
authors.affiliation: Department of Electric and Electronic Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Someya
mesh_terms: D006801:Humans; D008027:Light; D017785:Photons; D012867:Skin / Q000737:chemistry* / Q000378:metabolism; D013499:Surface Properties; D014173:Transistors, Electronic
keywords: PLED; flexible electronics; organic photo detector; pulse oximeter