Backplane configurations and operations

Patent metadata

Field	Value
Publication number	US-11710445-B2
Application number	US-202016739740-A
Country	US
Kind code	B2
Filing date	Jan 10, 2020
Priority date	Jan 24, 2019
Publication date	Jul 25, 2023
Grant date	Jul 25, 2023

Abstract

The disclosure describes various aspects of backplanes, including unit cells, architectures, and operations. In an aspect, a backplane unit cell is described that includes first and second switches, a storage element, a comparator, a source (e.g., a current or voltage source), where the source generates a drive signal to control light emission of a selected one of the light emitting elements in a display, and where the drive signal is based on a power signal selected by the second switch. In another aspect, a device is described that includes a backplane configured in an active matrix topology including multiple data columns and multiple row selects; and a set of electrical contacts associated with the active matrix topology and configured to electrically couple the backplane with the display, the display having multiple light emitting elements configured in a passive matrix topology. Methods of operation of the backplane are also described.

First claim

What is claimed is:

1. An apparatus, comprising:
multiple light emitting elements configured in a passive matrix topology and including a first group of light emitting elements and a second group of light emitting elements, the passive matrix topology does not include a respective driver cell for each of the multiple light emitting elements;
a backplane configured in an active matrix topology including:
a first data column and a second data column, the first data column including a driver cell configured to actively address each of the multiple light emitting elements in the first group of light emitting elements via a same transistor included in the driver cell, and
multiple row selects; and

a set of electrical contacts associated with the active matrix topology and configured to electrically couple the backplane with the multiple light emitting elements.

2. The apparatus of claim 1 , wherein the first data column and the second data column are directly accessible via an edge of the backplane.

3. The apparatus of claim 1 , wherein each electrical contact of the set of electrical contacts includes a bonding site.

4. The apparatus of claim 1 , each light emitting element of the multiple light emitting elements being a light-emitting diode that lacks a dedicated driver cell.

5. The apparatus of claim 1 , wherein each of the multiple row selects are directly accessible via an edge of the backplane.

6. An apparatus, comprising:
a display plane including a plurality of light emitting elements configured in a passive matrix topology and including a first group of light emitting elements and a second group of light emitting elements, the passive matrix topology does not include, a respective driver cell for each of the plurality of light emitting elements; and
a backplane including a data column from, a plurality of data columns, including a driver cell configured to actively address each of the plurality of light emitting elements in the first group of light emitting elements via a same transistor included in the driver cell, the plurality of data columns each configured to address multiple light emitting elements of the plurality of light emitting elements.

7. The apparatus of claim 6 , wherein the display plane including a plurality of passive-matrix row selects, the backplane including a plurality of row-select driver circuits each associated with a respective one of the plurality of passive-matrix row selects.

8. The apparatus of claim 6 , wherein the backplane includes a plurality of backplane unit cells each being electrically connected to at least one of the plurality of data columns and a set of light emitting elements of the plurality of light emitting elements.

9. The apparatus of claim 8 , wherein each of the plurality of backplane unit cells includes a switch, a storage element, and one of a current source and a voltage source.

10. The apparatus of claim 6 , wherein each light emitting element of the plurality of light emitting elements is a light-emitting diode that lacks a dedicated driver cell.

11. An apparatus comprising:
a backplane including a plurality of transistors and a data column including a driver cell;
a first emitter-group including a first plurality of light emitting elements, the driver cell configured to actively address each of the first plurality of light emitting elements via a same transistor included in the driver cell;
a second emitter-group including a second plurality of light emitting elements, the first emitter-group being in electrical connection with the second emitter-group without any of the plurality of transistors therebetween,
the first emitter-group being electrically connected to one of the plurality of transistors such that the first emitter-group is actively addressable by the backplane in an active matrix topology, and
the first plurality of light emitting elements within the first emitter-group is addressed in a passive matrix topology by virtue of each of the first plurality of light emitting elements being in electrical connection with each other.

Assignees

• Google Llc

Inventors

• He Gang

Classifications

• G09G3/32 Primary

  semiconductive, e.g. using light-emitting diodes [LED] · CPC title

• G09G3/3233 Primary

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

• G09G2300/06

  Passive matrix structure, i.e. with direct application of both column and row voltages to the light emitting or modulating elements, other than LCD or OLED · CPC title

• G09G2300/0842

  forming a memory circuit, e.g. a dynamic memory with one capacitor · CPC title

• G09G2320/0673

  for control of gamma adjustment, e.g. selecting another gamma curve · CPC title