US 11,960,683 B2
Display system with finger sensing
Bharat R. Acharya, Woodbury, MN (US); Robert D. Taylor, Stacy, MN (US); Joseph P. Attard, Woodbury, MN (US); Benjamin J. Forsythe, Stillwater, MN (US); David T. Yust, Woodbury, MN (US); Matthew E. Sousa, Rosemount, MN (US); Jason S. Petaja, Hudson, WI (US); Anthony M. Renstrom, Forest Lake, MN (US); William Blake Kolb, Stillwater, MN (US); Matthew S. Cole, Woodbury, MN (US); Matthew S. Stay, Bloomington, MN (US); Matthew R. D. Smith, Woodbury, MN (US); Jeremy O. Swanson, Woodbury, MN (US); Tri D. Pham, Woodbury, MN (US); David A. Rosen, North St. Paul, MN (US); Qunyi Chen, St. Paul, MN (US); Lisa A. DeNicola, St. Paul, MN (US); Quinn D. Sanford, Mosinee, WI (US); Carl A. Stover, St. Paul, MN (US); Lin Zhao, Woodbury, MN (US); and Gilles J. Benoit, Minneapolis, MN (US)
Assigned to 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
Appl. No. 17/996,583
Filed by 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
PCT Filed May 4, 2021, PCT No. PCT/IB2021/053751
§ 371(c)(1), (2) Date Oct. 19, 2022,
PCT Pub. No. WO2021/224798, PCT Pub. Date Nov. 11, 2021.
Claims priority of provisional application 63/021,760, filed on May 8, 2020.
Prior Publication US 2023/0214062 A1, Jul. 6, 2023
Int. Cl. G06F 3/042 (2006.01); F21V 8/00 (2006.01); G02B 5/02 (2006.01); G02B 5/30 (2006.01)
CPC G06F 3/0421 (2013.01) [G02B 5/0226 (2013.01); G02B 5/305 (2013.01); G02B 6/0051 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A display system for sensing a finger of a user applied to the display system, the display system comprising:
a display panel configured to generate an image for viewing by the user;
a sensor for sensing the finger of the user disposed proximate the display panel;
a sensing light source configured to emit a first light having a first wavelength W1 toward the finger of the user, the sensor configured to receive and detect at least a portion of the first light reflected by the finger; and
a reflective polarizer disposed between the display panel and the sensor and comprising a plurality of polymeric layers numbering at least 50 in total, such that for a substantially normally incident light, an optical transmittance of the reflective polarizer versus wavelength for a first polarization state comprises a band edge, wherein:
a best linear fit to the band edge correlating the optical transmittance to the wavelength at least across a wavelength range where the optical transmittance along the band edge increases from about 10% to at least about 70% has a slope of greater than about 2.5%/nm; and
for a first wavelength range extending from a smaller wavelength L1 to a greater wavelength L2 and comprising W1, 30 nm≤L2−L1≤50 nm, L1 greater than and within about 20 nm of a wavelength L3 corresponding to an optical transmittance of about 50% along the band edge, the optical transmittance has an average of greater than about 75%,
wherein for the substantially normally incident light and a predetermined wavelength range, the reflective polarizer has an average optical reflectance of at least 70% for the first polarization state and an average optical transmittance of at least 40% for an orthogonal second polarization state.