US 12,292,379 B2
Split refracting or split reflecting light received by cellulose-based film comprising surface pattern
Tapio Mäkelä, Espoo (FI); and Ari Hokkanen, Espoo (FI)
Assigned to Teknologian tutkimuskeskus VTT Oy, Espoo (FI)
Appl. No. 17/774,704
Filed by Teknologian tutkimuskeskus VTT Oy, Espoo (FI)
PCT Filed Nov. 5, 2020, PCT No. PCT/FI2020/050731
§ 371(c)(1), (2) Date May 5, 2022,
PCT Pub. No. WO2021/089921, PCT Pub. Date May 14, 2021.
Claims priority of application No. 20195952 (FI), filed on Nov. 5, 2019.
Prior Publication US 2022/0397524 A1, Dec. 15, 2022
Int. Cl. G01N 21/47 (2006.01); G01N 21/81 (2006.01)
CPC G01N 21/4788 (2013.01) [G01N 21/81 (2013.01)] 14 Claims
OG exemplary drawing
 
1. An apparatus comprising an optical position sensor device for capturing data and a processor, wherein the processor is configured to:
control the optical position sensor device to capture data from a cellulose nanofibril (CNF) film, when the CNF film is located in a field of view of the optical position sensor device, the CNF film comprising a surface pattern configured to
split refract or split reflect light received by the surface pattern into a plurality of output light patterns, wherein an output light pattern is determined from the plurality of output light patterns on the basis of an absorption of water to the CNF film; and
determine the absorption of water to the CNF film on the basis of the captured data indicating a change of one or more output light patterns, in response to the absorption of water of the CNF film.