Image acquiring device
Disclosed is an image acquiring device, including a liquid lens having a shape changed by pressurization, a membrane provided to one surface of the liquid lens, the membrane forming a pressurization surface, a pressurizing member provided to an outside of the membrane, and a support wire provided across a prescribed region of an outer surface of the pressurizing member, the support wire moving the pressurizing member toward the membrane by contracting by conduction, the support wire moving the pressurizing member toward an opposite side of the membrane by expanding. Accordingly, the present invention solves a problem of a mismatched focus in a close-up photo and minimizes an increasing volume of the image acquiring device.
1. An image acquiring device comprising:
a liquid lens having a shape varied by pressurization;
a case enclosing the liquid lens to accommodate the liquid lens therein;
a membrane provided to one surface of the liquid lens;
a pressurizing member contacting the membrane, the pressurizing member being entirely disposed within an outer circumference of the membrane; and
a support wire installed on the pressurizing member and configured to move the pressurizing member by a change of a length in a longitudinal direction of the support wire to selectively press the membrane, the support wire traversing the pressurizing member and extending beyond the membrane to connect opposite positions on the case,
wherein the support wire is configured to:
push the pressurizing member toward the membrane by contracting in the longitudinal direction in response to application of current; and
pull the pressurizing member away from the membrane by expanding in the longitudinal direction in response to non-application of the current.
2. The image acquiring device of claim 1 , wherein the pressurizing member is formed of metal material.
3. The image acquiring device of claim 1 , further comprising:
at least one lens located in rear of an optical path of the liquid lens; and
a lens body tube fixing the at least one lens.
4. The image acquiring device of claim 1 , wherein the support wire comprises shape-memory-alloy contracting in response to the application of the current.
5. The image acquiring device of claim 4 , wherein the pressurizing member comprises a ring member,
wherein a pair of insertion recesses parallel to each other are formed on both at both sides of an outer surface of the pressurizing member, and
wherein the support wire is fitted into the pair of insertion recesses so as to pressurize the both sides of the pressurizing member.
6. The image acquiring device of claim 5 , wherein the pair of insertion recesses are provided as parallel straight lines.
7. The image acquiring device of claim 5 , wherein the support wire is fixed in a polygonal shape including at least 6 line segments.
8. The image acquiring device of claim 5 , wherein the support wire is provided as a single body so as to pass through the pair of insertion recesses.
9. The image acquiring device of claim 8 , wherein an anode having a first end of the support wire connected thereto and a cathode having a second end of the support wire connected thereto are provided adjacent to the pair of insertion recesses.
10. The image acquiring device of claim 9 , further comprising:
a fixing portion provided to the case, the fixing portion provided to each of both sides of the pair of insertion recesses,
wherein the fixing portion comprises a first fixing member fixing the first end and the second end of the support wire and a second fixing member fixing a prescribed region of a center of the support wire.
11. The image acquiring device of claim 10 , further comprising an elastic member provided to the case so as to form a restoration force for spacing the pressurizing member apart from the liquid lens.