公开(公告)号：US11768145B2

公开(公告)日：2023-09-26

申请号：US17628735

申请日：2020-07-24

Applicant: 3M INNOVATIVE PROPERTIES COMPANY

Inventor： John A. Wheatley ,  William B. Kolb ,  Audrey A. Sherman ,  Mark A Roehrig ,  Alan R. Dombrowski ,  Kurt J. Halverson ,  Steven P. Swanson ,  Del R. Lawson ,  Cory M. Arthur

IPC: G01N15/08 ,  G01N21/78 ,  G01N21/81

CPC classification number: G01N15/0806 ,  G01N15/0826

Abstract: An optical element includes a porous layer with a network of a plurality of interconnected voids. The porous layer is optically diffusive to at least one wavelength of light when the network of interconnected voids is substantially free of fluid. The porous layer of the optical element undergoes a detectable optical change upon fluid ingress into the network or egress from the network of interconnected voids.