# US 11,308,875 B2 · Detection method of pixel circuit, driving method of display panel and display panel > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,308,875 B2 - Document ID: US11308875B2 - Status: Granted - Kind: B2 - Application number: 16/469,375 - Filed: 2019-01-15 - Published: 2021-11-25 - Granted: 2022-04-19 - Earliest claimed: 2018-04-26 - Assignees: Boe Technology Group Co., Ltd. - Applicants: Boe Technology Group Co., Ltd. - Inventors: Danna Song - Web page: https://patentgrep.com/patent/US11308875B2 ## CPC - G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element - G09G 3/3258: with pixel circuitry controlling the voltage across the light-emitting element - G09G 3/3291: in which the data driver supplies a variable data voltage for setting the current through, or the voltage across, the light-emitting elements - G09G 2300/0426: Layout of electrodes and connections - G09G 2300/0852: being a dynamic memory with more than one capacitor - G09G 2310/0278: Details of driving circuits arranged to drive both scan and data electrodes - G09G 2320/045: Compensation of drifts in the characteristics of light emitting or modulating elements - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) ## Abstract A detection method of a pixel circuit, a display panel and a driving method thereof are provided. The detection method includes: during a reference charging period, applying a reference data voltage to a gate electrode of a driving transistor, and at a first time duration after applying the reference data voltage, obtaining a benchmark voltage from a sensing line; and during a data charging period, applying a detection data voltage different from the reference data voltage to the gate electrode of the driving transistor, and at the first time duration after applying the detection data voltage, obtaining an initial sensing voltage from the sensing line. A sensing voltage of the pixel circuit is obtained based on at least the benchmark voltage and the initial sensing voltage, and a threshold voltage of the driving transistor is obtained based on the sensing voltage. ## Claims ### Claim 1 A detection method of a pixel circuit, the pixel circuit comprising a driving transistor, the driving transistor comprising a gate electrode and a first electrode, the first electrode of the driving transistor being coupled to a sensing line, the detection method comprising: during a reference charging period, applying a reference data voltage to the gate electrode of the driving transistor to charge the sensing line through the first electrode of the driving transistor, and at a first time duration after applying the reference data voltage, obtaining a benchmark voltage from the sensing line; and during a data charging period, applying a detection data voltage different from the reference data voltage to the gate electrode of the driving transistor to charge the sensing line through the first electrode of the driving transistor, and at the first time duration after applying the detection data voltage, obtaining an initial sensing voltage from the sensing line; wherein a sensing voltage of the pixel circuit is obtained based on at least the benchmark voltage and the initial sensing voltage, and a threshold voltage of the driving transistor is obtained based on the sensing voltage; wherein a predetermined interval is set between adjacent display frames; and the reference charging period and the data charging period are both in a same predetermined interval; wherein the reference charging period is before the data charging period; the detection method further comprises: during a supplementary reference charging period, applying the reference data voltage to the gate electrode of the driving transistor to charge the sensing line through the first electrode of the driving transistor, and at the first time duration after applying the reference data voltage, obtaining a supplementary benchmark voltage from the sensing line; wherein the reference charging period, the supplementary reference charging period and the data charging period are all in a same predetermined interval, and the supplementary reference charging period is after the data charging period; and the sensing voltage of the pixel circuit is obtained based on the benchmark voltage, the supplementary benchmark voltage and the initial sensing voltage. ### Claim 2 (depends on 1) The detection method according to claim 1, wherein the reference data voltage is zero. ### Claim 3 (depends on 2) The detection method according to claim 2, wherein the sensing voltage of the pixel circuit is equal to a difference between the initial sensing voltage and the benchmark voltage. ### Claim 4 (depends on 2) The detection method according to claim 2, wherein a predetermined interval is set between adjacent display frames; and the reference charging period and the data charging period are both in a same predetermined interval. ### Claim 5 (depends on 2) The detection method according to claim 2, wherein the pixel circuit further comprises a first transistor and a storage capacitor, a first electrode of the first transistor and a second electrode of the first transistor are respectively connected to a signal line and the gate electrode of the driving transistor, a first terminal of the storage capacitor and a second terminal of the storage capacitor are respectively connected to the gate electrode of the driving transistor and the first electrode of the driving transistor; the detection method further comprises: during the reference charging period, turning on the first transistor to continuously apply the reference data voltage to the gate electrode of the driving transistor in a time period before obtaining the benchmark sensing voltage; and during the data charging period, turning on the first transistor to continuously apply the detection data voltage to the gate electrode of the driving transistor in a time period before obtaining the initial sensing voltage. ### Claim 6 (depends on 1) The detection method according to claim 1, wherein the sensing voltage of the pixel circuit is equal to a difference between the initial sensing voltage and the benchmark voltage. ### Claim 7 (depends on 6) The detection method according to claim 6, wherein a predetermined interval is set between adjacent display frames; and the reference charging period and the data charging period are both in a same predetermined interval. ### Claim 8 (depends on 1) The detection method according to claim 1, wherein the sensing voltage of the pixel circuit is equal to a difference between the initial sensing voltage and an average of the benchmark voltage and the supplementary benchmark voltage. ### Claim 9 (depends on 1) The detection method according to claim 1, wherein the pixel circuit further comprises a first transistor and a storage capacitor, a first electrode of the first transistor and a second electrode of the first transistor are respectively connected to a signal line and the gate electrode of the driving transistor, a first terminal of the storage capacitor and a second terminal of the storage capacitor are respectively connected to the gate electrode of the driving transistor and the first electrode of the driving transistor; the detection method further comprises: during the reference charging period, turning on the first transistor to continuously apply the reference data voltage to the gate electrode of the driving transistor in a time period before obtaining the benchmark sensing voltage; and during the data charging period, turning on the first transistor to continuously apply the detection data voltage to the gate electrode of the driving transistor in a time period before obtaining the initial sensing voltage. ### Claim 10 (depends on 9) The detection method according to claim 9, wherein the pixel circuit further comprises a second transistor, a first electrode of the second transistor is connected to the first electrode of the driving transistor, and a second electrode of the second transistor is connected to the sensing line; the detection method further comprises: turning off the first transistor and the second transistor before obtaining the initial sensing voltage. ### Claim 11 (depends on 1) The detection method according to claim 1, wherein the pixel circuit further comprises a first transistor and a storage capacitor, a first electrode of the first transistor and a second electrode of the first transistor are respectively connected to a signal line and the gate electrode of the driving transistor, a first terminal of the storage capacitor and a second terminal of the storage capacitor are respectively connected to the gate electrode of the driving transistor and the first electrode of the driving transistor; the detection method further comprises: during the data charging period, turning off the first transistor after applying the detection data voltage to the gate electrode of the driving transistor, and re-turning on the first transistor before obtaining the initial sensing voltage; and during the turning off of the first transistor, a voltage supplied from the signal line to the gate electrode of the driving transistor is converted from the detection data voltage to a second detection data voltage having a voltage value less than the detection data voltage. ### Claim 12 (depends on 11) The detection method according to claim 11, wherein the second detection data voltage is zero. ### Claim 13 (depends on 1) The detection method according to claim 1, wherein a second electrode of the driving transistor is coupled to a first power voltage terminal to receive a first power voltage. ### Claim 14 A driving method of a display panel, the display panel comprising a pixel circuit and a sensing line, the pixel circuit comprising a driving transistor, the driving transistor comprising a gate electrode and a first electrode, the sensing line being coupled to the first electrode of the driving transistor, the driving method comprising: during a reference charging period, applying a reference data voltage to the gate electrode of the driving transistor to charge the sensing line through the first electrode of the driving transistor, and at a first time duration after applying the reference data voltage, obtaining a benchmark voltage from the sensing line; and during a data charging period, applying a detection data voltage different from the reference data voltage to the gate electrode of the driving transistor to charge the sensing line through the first electrode of the driving transistor, at the first time duration after applying the detection data voltage, obtaining an initial sensing voltage from the sensing line; wherein a sensing voltage of the pixel circuit is obtained based on at least the benchmark voltage and the initial sensing voltage, and a threshold voltage of the driving transistor is obtained based on the sensing voltage; wherein a predetermined interval is set between adjacent display frames; and the reference charging period and the data charging period are both in a same predetermined interval; wherein the reference charging period is before the data charging period; the driving method further comprises: during a supplementary reference charging period, applying the reference data voltage to the gate electrode of the driving transistor to charge the sensing line through the first electrode of the driving transistor, and at the first time duration after applying the reference data voltage, obtaining a supplementary benchmark voltage from the sensing line; wherein the reference charging period, the supplementary reference charging period and the data charging period are all in a same predetermined interval, and the supplementary reference charging period is after the data charging period; and the sensing voltage of the pixel circuit is obtained based on the benchmark voltage, the supplementary benchmark voltage and the initial sensing voltage. ### Claim 15 (depends on 14) The driving method of the display panel according to claim 14, further comprising: establishing a compensation amount of a sub-pixel unit comprising the pixel circuit according to the threshold voltage being obtained. ### Claim 16 (depends on 15) The driving method of the display panel according to claim 15, further comprising: during a display operation period of the display panel, compensating the sub-pixel unit with the compensation amount. ### Claim 17 A display panel, comprising a pixel circuit, a sensing line and a control circuit, wherein the pixel circuit comprises a driving transistor, the driving transistor comprises a gate electrode and a first electrode, the sensing line is coupled to the first electrode of the driving transistor; the control circuit is configured to perform a detection method of the pixel circuit or a driving method of the display panel as follows: during a reference charging period, applying a reference data voltage to the gate electrode of the driving transistor to charge the sensing line through the first electrode of the driving transistor, and at a first time duration after applying the reference data voltage, obtaining a benchmark voltage from the sensing line; and during a data charging period, applying a detection data voltage different from the reference data voltage to the gate electrode of the driving transistor to charge the sensing line through the first electrode of the driving transistor, and at the first time duration after applying the detection data voltage, obtaining an initial sensing voltage from the sensing line; wherein a sensing voltage of the pixel circuit is obtained based on at least the benchmark voltage and the initial sensing voltage, and a threshold voltage of the driving transistor is obtained based on the sensing voltage; wherein a predetermined interval is set between adjacent display frames; and the reference charging period and the data charging period are both in a same predetermined interval; wherein the reference charging period is before the data charging period; a detection method of the pixel circuit or a driving method of the display panel further comprises: during a supplementary reference charging period, applying the reference data voltage to the gate electrode of the driving transistor to charge the sensing line through the first electrode of the driving transistor, and at the first time duration after applying the reference data voltage, obtaining a supplementary benchmark voltage from the sensing line: wherein the reference charging period, the supplementary reference charging period and the data charging period are all in a same predetermined interval, and the supplementary reference charging period is after the data charging period; and the sensing voltage of the pixel circuit is obtained based on the benchmark voltage, the supplementary benchmark voltage and the initial sensing voltage.