Electrowetting element with multiple electrodes

A display apparatus comprising:

• an electrowetting element comprising:
• a first fluid;
• a second fluid immiscible with the first fluid;
• a first support plate comprising:
• a hydrophobic surface;
• at least one wall corresponding to a perimeter of the hydrophobic surface;
• a first electrode overlapped by a first portion of the hydrophobic surface;
• and
• a second electrode overlapped by a second portion of the hydrophobic surface, with the first portion and the second portion non-overlapping each other;
• and
• a second support plate, the first fluid and the second fluid located between the first support plate and the second support plate;
• at least one processor;
• and
• at least one memory comprising computer program instructions, the at least one memory and the computer program instructions operable to, with the at least one processor:
• receive input data indicative of a grey level;
• in response to the input data:
• apply a sequence of voltages between the second fluid and the first electrode and between the second fluid and the second electrode to translate the first fluid across the hydrophobic surface such that:
• the first fluid is in contact with at least part of the first portion at a first time and is in a first configuration corresponding to the grey level;
• the first fluid is in contact with at least part of the second portion at a second time subsequent to the first time and is in a second configuration corresponding to the grey level, the second configuration different from the first configuration;
• and
• the first fluid is in contact with the at least part of the first portion at a third time subsequent to the first time and the second time.

An electrowetting display device comprising:

• an electrowetting element comprising:
• a first fluid;
• a second fluid immiscible with the first fluid;
• a first support plate having a hydrophobic surface, the first support plate comprising:
• at least one wall corresponding to a perimeter of the hydrophobic surface, the at least one wall comprising:
• a first wall portion, the first wall portion being substantially straight in a plane parallel to a plane of the hydrophobic surface;
• a second wall portion, the second wall portion being substantially straight in the plane parallel to the plane of the hydrophobic surface;
• and
• a third wall portion which connects the first wall portion to the second wall portion, the third wall portion being curved in the plane parallel to the plane of the hydrophobic surface;
• a first electrode overlapped by a first portion of the hydrophobic surface;
• and
• a second electrode overlapped by a second portion of the hydrophobic surface, with the first portion and the second portion non-overlapping each other;
• and
• a second support plate, the first fluid and the second fluid located between the first support plate and the second support plate;
• an additional electrode;
• and
• a control system operable to, in response to input data indicative of a first grey level:
• apply a first voltage between the additional electrode and the first electrode such that the second fluid is in contact with at least part of the first portion and is in a first configuration corresponding to the first grey level;
• and,
• subsequently, apply a second voltage between the additional electrode and the second electrode to translate the first fluid such that the second fluid is in contact with at least part of the second portion and is in a second configuration corresponding to the first grey level, the second configuration different from the first configuration.