US 7,623,113 B2 · Method of compensating temperature dependence of driving schemes for electrophoretic displays

Abstract

An image is updated on a bi-stable display (310) such as an electrophoretic display by providing separate scaling functions (SF1, SF2) for scaling a duration of a reset pulse (R) and a duration of a driving pulse (D) in a drive waveform based on temperature (335). An absolute value of a slope with varying temperatures of the scaling factor (SF1) for the reset pulse (R) is significantly greater than that of the scaling factor (SF2) for the driving pulse (D), while both scaling factors increase with decreasing temperature. Image update time (IUT) is significantly reduced at lower temperatures, while a range of variation of IUT across all temperatures is also reduced. Scaling functions (SF3, SF4) may also be used for scaling a duration of a help reset pulse (H) and/or a duration of one or more shaking pulses (SH1, SH2).

Claims17

Dependent claims

A method for driving a bi-stable display, comprising:

determining a temperature (T) associated with the bi-stable display (310);
determining a duration for applying a reset pulse (R) to at least a portion of the bi-stable display based on the determined temperature and a first scaling function (SF2);
and
determining a duration for applying a driving pulse (D) to the at least a portion of the bi-stable display based on the determined temperature and a second scaling function that differs from the first scaling function (SF2), wherein an absolute value of a slope of the first scaling function with varying temperature is less than an absolute value of a slope of the second scaling function when the determined temperature is below a reference temperature (Tref).

1 more element

A program storage device tangibly embodying a program of instructions executable by a machine to perform a method for updating an image on a bi-stable display, the method comprising:

determining a temperature(T) associated with the bi-stable display(310);
determining a duration for applying a reset pulse (R) to at least a portion of the bi-stable display based on the determined temperature and a first scaling function (SF2);
and
determining a duration for applying a driving pulse (D) to the at least a portion of the bi-stable display based on the determined temperature and a second scaling function (SF1) that differs from the first scaling function (SF2), wherein an absolute value of a slope of the first scaling function with varying temperature is less than an absolute value of a second scaling function when the determined temperature is below a reference temperature (Tref).

1 more element

An electronic reading device, comprising:

a bi-stable display (310);
and
a control (100) for updating an image on the bi-stable display by:
(a) determining a temperature (T) associated with the bi-stable display, (b) determining a duration for applying a reset pulse (R) to at least a portion of the bi-stable display based on the determined temperature and a first scaling function (SF2), and (e) determining a duration for applying a driving pulse (D) to the at least a portion of the bi-stable display based on the determined temperature and a second scaling function (SF1) that differs from the first scaling function, wherein an absolute value of a slope of the first scaling function with varying temperature is less than an absolute value of a slope of the second scaling function when the determined temperature is below a reference temperature (Tref).

1 more element

Dependencies are inferred from the claim text.

Method of compensating temperature dependence of driving schemes for electrophoretic displays

Life of this patent

Method of compensating temperature dependence of driving schemes for electrophoretic displays

Life of this patent

Abstract

Claims17