Joled Inc.

Eiji Iwauchi

Kazuhiro Yoneda

Kazuki Sawa

Tomoyuki Maeda

Masafumi Matsui

A display device includes: a luminance converter which converts input gradation value into a corresponding target luminance value; a luminance correction calculator which calculates output gradation value from the target luminance value and calculates a corrected luminance value from the output gradation value, using an efficiency residual ratio which is an index representing the light-emitting element deterioration degree; a current stress calculator which converts current stress amount on the light-emitting element calculated from the corrected luminance value into current stress amount when reference current flows through the light-emitting element, and calculates the accumulated current stress amount; a temperature stress calculator which converts temperature stress amount on the light-emitting element under environmental temperature into temperature stress amount on the light-emitting element under reference temperature, and calculates the accumulated current stress amount; and an efficiency residual ratio calculator which updates the efficiency residual ratio, using the accumulated current and temperature stress amounts.

Display device and display device driving method

A display device includes: a luminance converter which converts input gradation value into a corresponding target luminance value; a luminance correction calculator which calculates output gradation value from the target luminance value using efficiency residual ratio representing a deterioration degree of a light-emitting element, and calculates a corrected luminance value therefrom; a current stress calculator which converts current stress amount on a light-emitting element calculated from the corrected luminance value into current stress amount when first reference current flows through the light-emitting element, and accumulates this to calculate an accumulated first stress amount; a CB stress calculator which converts CB stress amount on the light-emitting element into current stress amount when second reference current flows through the light-emitting element, and accumulates this to calculate an accumulated second stress amount; and an efficiency residual ratio calculator which updates the efficiency residual ratio, using the accumulated first and second stress amounts calculated.

A display device includes: luminance converter that converts an input gradation value into a target luminance value corresponding to the input gradation value; correction calculator that calculates an output gradation value from the target luminance value and calculates a corrected luminance value from the output gradation value using an efficiency residual rate; cumulative stress calculator that updates the efficiency residual rate using a cumulative stress amount obtained by converting a stress amount on the light emitting element calculated from the corrected luminance value into a first stress amount at a reference current and accumulating a second stress amount obtained by converting the converted first stress amount according to a frame rate; and stress amount converter that converts the first stress amount into the second stress amount by multiplying the first stress amount by a conversion coefficient corresponding to the frame rate obtained from the video signal.

Display device and method for driving display device

A display device includes: a display unit which includes a plurality of pixels each including an organic EL element; and a control unit which adjust a value of a luminance signal to be supplied to a target pixel to be corrected, such that an actual luminance of the target pixel is equal to a reference luminance, the reference luminance being an actual luminance of a reference pixel obtained when the luminance signal to be supplied to the target pixel is supplied to the reference pixel. The reference pixel has predetermined attenuation characteristics for light emission amount.

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Tokyo, Japan

Eiji Iwauchi