Camera module including liquid lens and control method thereof
A camera module including a liquid lens, according to one embodiment, includes: a liquid lens including a first plate, and an individual electrode arranged on a first surface of the first plate; a temperature detection element arranged on the first surface of the first plate so as to be spaced apart from the individual electrode; a heating element arranged on the first surface so as to be spaced apart from the temperature detection element and the individual electrode; a temperature sensor connected to the temperature detection element to sense the temperature of the liquid lens; and a heating controller connected to the heating element.
1 . A camera module, comprising:
a liquid lens comprising:
a first plate having a first surface and a second surface opposite the first surface, the first surface having a larger area than the second surface;
a second plate disposed on the first surface;
a conductive liquid;
an insulative liquid;
an individual electrode disposed on the first surface of the first plate; and
a common electrode disposed on the second surface of the first plate, the common electrode being in direct contact with the conductive liquid;
a temperature detection element disposed on the first surface of the first plate so as to be spaced apart from the individual electrode;
a heating element disposed on the first surface so as to be spaced apart from the temperature detection element and the individual electrode;
a temperature sensor connected to the temperature detection element to sense a temperature of the liquid lens;
a heating controller connected to the heating element, wherein the individual electrode is located closer to an outer edge of the first surface than the temperature detection element and the heating element; and
a connection substrate connected to the individual electrode and the temperature detection element,
wherein the second plate includes a plurality of recesses exposing a first end of the temperature detection element and a second end of the heating element, and
wherein the connection substrate includes a plurality of protruding portions protruding toward the plurality of recesses to be connected to the first and second ends.
2 . The camera module according to claim 1 ,
wherein the heating element and the temperature detection element are disposed so as to face each other, with a center of the liquid lens interposed therebetween.
3 . The camera module according to claim 2 ,
wherein the temperature detection element and the heating element are disposed between the first surface of the first plate and the second plate.
4 . The camera module according to claim 1 , wherein the temperature detection element comprises one end connected to the temperature sensor and an opposite end connected to a reference potential, and
wherein the heating element comprises one end connected to the heating controller and an opposite end connected to the reference potential.
5 . The camera module according to claim 4 , wherein the temperature sensor comprises:
a sensing driver configured to supply a driving signal to the one end of the temperature detection element; and
a temperature information measurer connected to the one end of the temperature detection element to measure temperature information of the temperature detection element.
6 . The camera module according to claim 5 , wherein the sensing driver comprises at least one of:
a current source connected to the one end of the temperature detection element to supply the driving signal in a form of current; and
a load resistor connected between the driving signal having a voltage form and the one end of the temperature detection element.
7 . The camera module according to claim 1 , wherein the first surface of the first plate comprises a first area and a second area facing the first area with a center of the liquid lens interposed therebetween,
wherein the heating element comprises a heating element disposed in at least one of the first area or the second area, and
wherein the temperature detection element comprises a temperature detection element disposed in at least one of the first area or the second area.
8 . The camera module according to claim 7 , wherein the heating element comprises:
a first heating element disposed in the first area; and
a second heating element disposed in the second area.
9 . The camera module according to claim 8 , wherein the first heating element and the second heating element are disposed so as to face each other in a diagonal direction with respect to the center of the liquid lens.
10 . The camera module according to claim 7 , wherein the temperature detection element comprises:
a first temperature detection element disposed in the first area; and
a second temperature detection element disposed in the second area.
11 . The camera module according to claim 10 , wherein the first temperature detection element and the second temperature detection element are disposed so as to face each other in a diagonal direction with respect to the center of the liquid lens.
12 . The camera module according to claim 1 , wherein the conductive liquid and the insulative liquid are accommodated in a cavity of the first plate,
wherein the first plate includes a first opening and a second opening, the first and second openings defining the cavity,
wherein the first opening has a smaller area than the second opening, and
wherein the first surface is a surface around the first opening and the second surface is a surface around the second opening.
13 . The camera module according to claim 1 , further comprising an insulation layer located between the individual electrode and each of the temperature detection element and the heating element.