Integrated display and sensing apparatus

Patent metadata

Field	Value
Publication number	US-12326997-B2
Application number	US-202016736382-A
Country	US
Kind code	B2
Filing date	Jan 7, 2020
Priority date	Aug 25, 2017
Publication date	Jun 10, 2025
Grant date	Jun 10, 2025

Abstract

An apparatus includes a backplane, a light emitting layer, a sensing layer, and a cover layer. The backplane includes an array of display pixel circuits and an array of sensing pixel circuits formed on a same substrate. The light emitting layer includes an array of light emitting elements above the backplane. Each display pixel circuit is configured to drive a plurality of light emitting elements. The sensing layer includes an array of optical sensing elements above the light emitting layer. Each sensing pixel circuit is configured to drive a respective optical sensing element. The cover layer is above the sensing layer. When an object is in contact with the cover layer, at least one optical sensing element is configured to detect optical information of the object based, at least in part, on light generated by at least one light emitting element and reflected by the object.

First claim

What is claimed is:

1. An apparatus, comprising:
a backplane comprising an array of display pixel circuits and an array of sensing pixel circuits, wherein the array of display pixel circuits and the array of sensing pixel circuits are formed on a same substrate;
a light emitting layer comprising an array of light emitting elements divided into k groups of light emitting elements, k being an integer larger than 1, wherein each display pixel circuit of the array of display pixel circuits is configured to drive k light emitting elements from each of the k groups of light emitting elements in a respective one of k sub-frame periods within a frame period, the array of light emitting elements is arranged in x rows and y columns, and the array of display pixel circuits is driven by x/k gate lines and y source lines;
a black matrix disposed between adjacent light emitting elements;
a sensing layer comprising an array of optical sensing elements, wherein each sensing pixel circuit of the array of sensing pixel circuits is configured to drive a respective optical sensing element in the array of optical sensing elements, and the black matrix is disposed overlapping the array of optical sensing elements; and
a cover layer above the sensing layer and the light emitting layer,
wherein:
the k light emitting elements comprise a first light emitting element connected with a first light emitting transistor and a second light emitting element connected with a second light emitting transistor, and the k sub-frame periods comprise a first sub-frame period and a second sub-frame period that is non-overlapping with the first sub-frame period;
in response to a switching transistor being turned on by a scan signal, a storage capacitor, connected with a terminal of a light emitting control transistor and a terminal of a driving transistor, is being charged with a data signal received discontinuously;
in response to, during the first sub-frame period where the data signal pauses, the light emitting control transistor being turned on by a light emitting control signal and the first light emitting transistor being turned on by a first light emitting signal, a first current flows through the driving transistor to the first light emitting element according to a charged level of the storage capacitor, the light emitting control signal being independent of the scan signal;
in response to, during the second sub-frame period after the first sub-frame period, the light emitting control transistor being turned on by the light emitting control signal and the second light emitting transistor being turned on by a second light emitting signal, a second current flows through the driving transistor to the second light emitting element according to the charged level of the storage capacitor;
the light emitting layer is formed above the backplane; and
when an object is in contact with the cover layer, at least one optical sensing element of the array of optical sensing elements detects optical information of the object based, at least in part, on light generated by at least one light emitting element of the array of light emitting elements and reflected by the object, wherein the at least one optical sensing element and the at least one light emitting element are located in a sub-area smaller than a size of the light emitting layer, a number of the at least one optical sensing element being less than a total number of the optical sensing elements in the respective array, a number of the at least one light emitting element being less than a total number of the light emitting elements in the respective array, wherein;
a number of sensing pixel circuits in the array of sensing pixel circuits, arranged in the backplane, is 1/k of a number of light emitting elements in the array of light emitting elements arranged in the light emitting layer, and the sensing layer contains no thin-film transistors to increase an aperture ratio of the sensing layer for improving fingerprint recognition; and
a location of the sub-area on the apparatus is dynamically changed in response to movement of the object.

2. The apparatus of claim 1 , wherein the sensing layer further comprises an object sensor configured to detect the sub-area in which the object is in contact with the cover layer, the sub-area being a predefined region.

3. The apparatus of claim 2 , wherein before the object is in contact with the cover layer, the array of light emitting elements is configured to emit light to display an image indicating the predefined region.

4. The apparatus of claim 1 , wherein when the object is in contact with the cover layer, the at least one light emitting element of the array of light emitting elements is configured to emit light in a same color.

5. The apparatus of claim 4 , wherein:
a first beam of light penetrates through the sensing layer and the cover layer to irradiate an interface between the cover layer and the object; and
at least part of the first beam of light is reflected at the interface to form a second beam of light that is transmitted back to the at least one optical sensing element of the array of optical sensing elements.

6. The apparatus of claim 4 , wherein the at least one light emitting element in the sub-area functions as a light source for recognizing the object, and other light emitting elements outside the sub-area display an image.

7. The apparatus of claim 1 , wherein the k light emitting elements driven by a same display pixel circuit are arranged in a same column of the array of light emitting elements.

8. The apparatus of claim 1 , wherein each of the k groups of light emitting elements comprises one or more entire rows of the array of light emitting elements.

9. The apparatus of claim 1 , wherein the k light emitting elements driven by a same display pixel circuit receive display data via a same source line.

10. The apparatus of claim 1 , further comprising:
a plurality of scan lines operatively coupled to the array of display pixel circuits, wherein each of the plurality of scan lines is shared by k rows of light emitting elements from each of the k groups of light emitting elements.

11. The apparatus of claim 1 , further comprising:
a light emitting driving circuit operatively coupled to the array of display pixel circuits and configured to cause each of the k groups of light emitting elements to sequentially emit light in a respective one of the k sub-frame periods within a frame period; and
a gate driving circuit operatively coupled to the array of display pixel circuits and configured to sequentially scan each of the k groups of light emitting elements in the respective sub-frame period within the frame period.

12. The apparatus of claim 1 , wherein each light emitting element of the array of light emitting elements is a top-emitting organic light emitting diode (OLED).

13. The apparatus of claim 1 , further comprising:
a row selector circuit operatively coupled to the array of sensing pixel circuits and configured to scan the at least one optical sensing element of the array of optical sensing elements; and
a column readout circuit operatively coupled to the array of sensing pixel circuits and configured to read signals from the at least one optical sensing element of the array of optical sensing elements,
wherein only the optical sensing elements in the sub-area are selected by the row selector circuit for optical sensing.

14. The apparatus of claim 1 , wherein each optical sensing element of the array of optical sensing elements is a photodiode.

15. The apparatus of claim 1 , wherein when the object is in contact with the cov

Assignees

• Viewtrix Tech Co Ltd
• Kunshan Govisionox Optoelectronics Co Ltd

Inventors

• Gu Jing
• Zhu Xiujian

Classifications

• G09G2360/148

  the light being detected by light detection means within each pixel · CPC title

• G09G2300/0465

  Improved aperture ratio, e.g. by size reduction of the pixel circuit, e.g. for improving the pixel density or the maximum displayable luminance or brightness · CPC title

• G09G3/3233

  with pixel circuitry controlling the current through the light-emitting element · CPC title

• G06F3/0412 Primary

  Digitisers structurally integrated in a display · CPC title

• G06F3/041661

  using detection at multiple resolutions, e.g. coarse and fine scanning; using detection within a limited area, e.g. object tracking window · CPC title