Backlight module and driving method thereof using subfields with different durations

A driving method of a backlight module, wherein the backlight module comprises a plurality of backlight units disposed in an array, and each backlight unit is arranged corresponding to a partition of a liquid crystal display panel, the driving method comprising following steps:

• obtaining backlight data corresponding to each backlight unit in a current frame, wherein the backlight data comprises N bits of data, and N is a positive integer;
• dividing time required by each backlight unit in the current frame to obtain N subfields with different durations, wherein each subfield is configured to display one bit of data;
• and
• outputting the N subfields of each backlight unit in a preset order, and controlling respective scan lines corresponding to each backlight unit to scan once in turn when each subfield is output, wherein multiple subfields corresponding to each of at least one of the backlight units comprise at least one first subfield with a duration greater than a first threshold, each of the scan lines corresponding to the backlight unit is controlled to perform at least two scans in each of the at least one first subfield, and a time interval between adjacent scans of the at least two scans is less than a second threshold,
• wherein each backlight unit comprises light emitting devices disposed in an array, the light emitting devices are driven by a backlight drive circuit, a value of the first threshold is greater than a sum of scan time of the scan line and a maximum retention time of a storage capacitor in the backlight drive circuit, and a value of the second threshold is the maximum retention time of the storage capacitor, and
• wherein in the N subfields corresponding to each of at least one of the backlight units, one scan is performed in multiple subfields of the N subfields before the at least one first subfield.