US-12619131-B2 - Camera module including liquid lens and control method thereof

US12619131B2US 12619131 B2US12619131 B2US 12619131B2US-12619131-B2

Abstract

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.

Inventors

Jung Bae Park
Young Woon Kim
Young Seop Moon

Assignees

LG INNOTEK CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20191209
Priority Date: 20181217

Claims (13)

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.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is the National Phase of PCT/KR2019/017301 filed on Dec. 9, 2019, which claims priority under 35 U.S.C. § 119(a) to Patent Application No. 10-2018-0163270 filed in the Republic of Korea on Dec. 17, 2018, all of which are hereby expressly incorporated by reference into the present application. TECHNICAL FIELD Embodiments relate to a camera module including a liquid lens and a control method thereof. BACKGROUND ART People who use portable devices demand optical devices that have high resolution, are small, and have various photographing functions. For example, these various photographing functions may be at least one of an optical zoom-in/zoom-out function, an auto-focusing (AF) function, or a hand-tremor compensation or optical image stabilization (OIS) function. In the conventional art, in order to implement the various photographing functions described above, a method of combining a plurality of lenses and directly moving the combined lenses is used. In the case in which the number of lenses is increased, however, the size of the optical device may increase. The auto-focusing and hand-tremor compensation functions are performed by moving or tilting a plurality of lenses, which are secured to a lens holder and are aligned along an optical axis, in an optical-axis direction or a direction perpendicular to the optical axis. To this end, a separate lens-moving apparatus is required in order to move a lens assembly composed of a plurality of lenses. However, the lens-moving apparatus has high power consumption, and an additional cover glass needs to be provided separately from a camera module in order to protect the lens-moving apparatus, thus causing a problem in that the overall size of the conventional camera module is increased. In order to solve this, studies have been conducted on a liquid lens that performs auto-focusing and hand-tremor compensation functions by electrically adjusting the curvature and tilting of an interface between two types of liquids. DISCLOSURE Technical Problem Embodiments provide a camera module including a liquid lens that is capable of controlling the temperature of the liquid lens and a control method thereof. The objects to be accomplished by the embodiments are not limited to the above-mentioned objects, and other objects not mentioned herein will be clearly understood by those skilled in the art from the following description. Technical Solution A camera module according to an embodiment may include a liquid lens including a first plate and an individual electrode disposed on a first surface of the first plate, 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, and a heating controller connected to the heating element. For example, the camera module may include a connection substrate connected to the individual electrode and the temperature detection element, and the heating element and the temperature detection element may be disposed so as to face each other, with the center of the liquid lens interposed therebetween. For example, the temperature detection element may include one end connected to the temperature sensor and an opposite end connected to a reference potential, and the heating element may include one end connected to the heating controller and an opposite end connected to the reference potential. For example, the temperature sensor may include 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. For example, the first surface of the first plate may include a first area and a second area facing the first area, the heating element may include a first heating element disposed in the first area and a second heating element disposed in the second area, and the temperature detection element may include a temperature detection element disposed in at least one of the first area and the second area. For example, the first heating element and the second heating element may be disposed so as to face each other in a diagonal direction with respect to the center of the liquid lens. For example, the sensing driver may include at least one of a current source, connected to the one end of the temperature detection element to supply the driving signal in the 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. For example, the first plate may include a second surfac