Optical film for oxygen saturation sensing

Patent metadata

Field	Value
Publication number	US-2024023905-A1
Application number	US-202118266049-A
Country	US
Kind code	A1
Filing date	Dec 15, 2021
Priority date	Dec 16, 2020
Publication date	Jan 25, 2024
Grant date	—

Abstract

A display system for sensing a user body portion, including a display panel configured to form an image for viewing by the user, an optical reflector having a plurality of polymeric layers, and at least one optical sensor for sensing a visible light having at least one visible wavelength and an infrared light having at least one infrared wavelength. The optical sensor senses the visible and infrared lights after the visible and infrared lights are transmitted by the optical reflector. The optical reflector has an average optical reflectance greater than 80% in the visible wavelength range, an optical transmittance greater than about 50% at the infrared wavelength, an optical transmittance of greater than about 2% and less than about 10% at the visible wavelength, and an optical transmittance versus wavelength with a bandpass segment having a full width at half maximum that includes the visible wavelength.

First claim

1 . A display system for sensing a user body portion placed at or proximate to the display system, the display system comprising:
a display panel configured to form an image for viewing by the user; an optical reflector comprising a plurality of polymeric layers numbering at least 50 in total, each of the polymeric layers having an average thickness of less than about 500 nm; and at least one optical sensor configured to sense a visible light having at least one visible wavelength in a visible wavelength range extending from about 420 nm to about 680 nm and an infrared light having at least one infrared wavelength in an infrared wavelength range extending from about 750 to about 1500 nm, the at least one optical sensor sensing the visible and infrared lights after the visible and infrared lights are transmitted by the optical reflector; such that for a substantially normally incident light, the plurality of polymeric layers of the optical reflector has: an average optical reflectance of greater than about 80% in the visible wavelength range; an optical transmittance of greater than about 50% at the at least one infrared wavelength; an optical transmittance of greater than about 2% and less than about 10% at the at least one visible wavelength; and an optical transmittance versus wavelength that comprises a bandpass segment comprising a full width at half maximum (FWHM) that comprises the at least one visible wavelength.

2 . The display system of claim 1 further configured to image the user body portion.

3 . The display system of claim 1 , wherein the user body portion comprises one or more of a finger of the user, a palm of the user, a vein of the user, a face of the user, and a vein pattern of the user.

4 . The display system of claim 1 , wherein the at least one optical sensor is configured to at least measure an intensity of at least one of the visible and infrared lights, and form a one- or a two-dimensional image of the user body portion.

5 . The display system of claim 1 , wherein the at least one optical sensor comprises a visible-light optical detector configured to sense the visible light having the at least one visible wavelength, and an infrared-light optical detector configured to sense the infrared light having the at least one infrared wavelength.

6 . The display system of claim 1 further comprising at least one light source configured to emit the visible light having the at least one visible wavelength and the infrared light having the at least one infrared wavelength, such that the emitted visible and infrared lights are sensed by the at least one optical sensor after the emitted visible and infrared lights are first reflected by the user body portion and then transmitted by the optical reflector.

7 . The display system of claim 6 , wherein the at least one light source comprises a visible-light light source configured to emit the visible light having the at least one visible wavelength and an infrared-light light source configured to emit the infrared light having the at least one infrared wavelength.

8 . The display system of claim 1 , wherein the optical reflector is disposed between the display panel and the at least one optical sensor.

9 . The display system of claim 1 further comprising a light redirecting layer disposed on the optical reflector for redirecting at least one of the visible and infrared lights from propagating along a first direction to a propagating along a different second direction.

10 . The display system of claim 9 , wherein the light redirecting layer comprises a plurality of prisms.

11 . The display system of claim 8 further comprising at least one light source configured to emit the visible light having the at least one visible wavelength and the infrared light having the at least one infrared wavelength, the optical reflector disposed between the display panel and the at least one light source, such that the emitted visible and infrared lights are sequentially transmitted by the optical reflector, transmitted by the display panel, reflected by the user body portion, transmitted by the display panel, transmitted by the optical reflector, and sensed by the at least one optical sensor.

12 . The display system of claim 8 further comprising a visible-light light source comprised by the display panel and configured to emit the visible light having the at least one visible wavelength and an infrared-light light source disposed between the display panel and the optical reflector and configured to emit the infrared light having the at least one infrared wavelength, such that the emitted visible light is sequentially reflected by the user body portion, transmitted by the display panel, transmitted by the optical reflector, and sensed by the at least one optical sensor, and the emitted infrared light is sequentially transmitted by the display panel, reflected by the user body portion, transmitted by the display panel, transmitted by the optical reflector, and sensed by the at least one optical sensor.

13 . The display system of claim 1 , wherein at least one of the at least one optical sensor is disposed between the optical reflector and the display panel.

14 . The display system of claim 13 configured to sense a user body portion applied to a back side of the display system opposite the image formed by the display panel.

15 . The display system of claim 14 further comprising a cover disposed on the back side of the display system, the optical reflector disposed between the cover and the at least one optical sensor, such that for a substantially normally incident light and for each of the at least one visible wavelength and the at least one infrared wavelength, the cover has an optical transmittance of greater than about 50%.

16 . The display system of claim 14 further comprising at least one light source disposed between the optical reflector and the display panel and configured to emit the visible light having the at least one visible wavelength and the infrared light having the at least one infrared wavelength, such that the emitted visible and infrared lights are sequentially transmitted by the optical reflector, reflected by the user body portion, transmitted by the optical reflector, and sensed by the at least one optical sensor.

17 . The display system of claim 16 , wherein the at least one light source comprises a visible-light light source configured to emit the visible light having the at least one visible wavelength and an infrared-light light source configured to emit the infrared light having the at least one infrared wavelength.

18 . The display system of claim 14 further comprising a display 12 comprising the display panel disposed between first and second polarizers.

19 . The display system of claim 18 , wherein at least one of the first and second polarizers comprises an absorbing polarizer.

20 - 32 . (canceled)

33 . A display system comprising first and second optical reflectors, each of the optical reflectors comprising a plurality of polymeric layers numbering at least 50 in total, each of the polymeric layers having an average thickness of less than about 500 nm, such that for a substantially normally incident light, at least one visible wavelength in a visible wavelength range extending from about 420 nm to about 680 nm, and at least one infrared wavelength in an infrared wavelength range extending from about 750 to about 1500 nm:
the plurality of polymeric layers of each of the optical reflectors has an average op

Assignees

• 3M Innovative Properties Company

Inventors

• Liu Zhiping
• Long Fan
• Wheatley John A
• Acharya Bharat R
• Fabick Ryan T
• Hu Zhe
• Kivel Edward J

Classifications

• A61B5/7445 Primary

  Display arrangements, e.g. multiple display units · CPC title

• A61B5/0062

  Arrangements for scanning · CPC title

• A61B5/117

  Identification of persons (methods or arrangements for recognising patterns, e.g. fingerprints, G06F18/00, G06V40/00; identification of persons by analysing their voice or speech G10L17/00) · CPC title

• A61B5/14552

  Details of sensors specially adapted therefor · CPC title

• A61B5/6826

  Finger · CPC title