# US 7,609,959 B2 · Automatic focusing structure and digital camera module with same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,609,959 B2 - Document ID: US7609959B2 - Status: Granted - Kind: B2 - Application number: 11/448,574 - Filed: 2006-06-07 - Published: 2007-04-05 - Granted: 2009-10-27 - Earliest claimed: 2005-09-30 - Assignees: Hon Hai Precision Industry Co., Ltd. - Inventors: Tai-Cherng Yu - Web page: https://patentgrep.com/patent/US7609959B2 ## CPC - G03B 3/10: Power-operated focusing - G02B 7/08: adapted to co-operate with a remote control mechanism - G02B 13/001: {Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras (G02B23/243 takes precedence)} - H04N 23/55: Optical parts specially adapted for electronic image sensors; Mounting thereof - H04N 23/67: Focus control based on electronic image sensor signals - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract An automatic focusing structure includes a holder (20), a barrel (10) and a piezoelectric actuator (30). The holder has a resistor (26) thereon. The barrel is slidably received in the holder. At least one lens element (12) received in the barrel, and an electrode (16) is located on an outer periphery wall of the barrel. The electrode slidably contacts the resistor. The actuator mounted under the barrel to move relative to the holder. When the barrel slides relative to the holder, the resistance value of the resistor is changed. Information from the resistor corresponds to a position information of the barrel, and the position information is feedback to the actuator so as to adjust the position of the barrel. ## Claims ### Claim 1 An automatic focusing structure, comprising: a holder including a resistor thereon; a barrel slidably received in the holder, at least one lens element received in the barrel, an electrode located on an outer periphery wall of the barrel, the electrode slidably contacting with the resistor; and a piezoelectric actuator, the piezoelectric actuator mounted under the barrel for moving the barrel relative to the holder; wherein when the barrel slides relative to the holder, the resistance value of the resistor is changed, information of the resistor corresponds to a position information of the barrel, and the position information is fed back to the piezoelectric actuator so as to adjust the position of the barrel. ### Claim 2 (depends on 1) The automatic focusing structure as claimed in claim 1, wherein the outer periphery wall defines a groove, and the electrode is received in and adheres to the groove. ### Claim 3 (depends on 1) The automatic focusing structure as claimed in claim 1, wherein the holder includes a holder body and a flange, the holder body is a hollow cylinder, and the flange is a long cube. ### Claim 4 (depends on 3) The automatic focusing structure as claimed in claim 3, wherein the flange defines a rectangular cavity, and the rectangular cavity communicates with the holder body. ### Claim 5 (depends on 1) The automatic focusing structure as claimed in claim 1, wherein the holder defines a notch, and the resistor is received in the notch. ### Claim 6 (depends on 1) The automatic focusing structure as claimed in claim 1, wherein the electrodes and the resistors further connect with an anode and a cathode of a power source for providing the movement position of the lens module to the piezoelectric actuator, and the piezoelectric actuator further adjusts the position of the lens module. ### Claim 7 A digital camera module, comprising: a lens module including a barrel; a holder carrying the lens module and defining a notch; a piezoelectric actuator mounted to the lens module and configured for driving the lens module to slide relative to the holder; a passive feedback unit configured for providing the movement position or the lens module to the piezoelectric actuator, and the piezoelectric actuator further adjusting the position of the lens module, the passive feedback unit including a resistor, an electrode and a power source connected to each other, the resistor being received in the notch, the electrode slidably contacting with the resistor; and an image sensor, the image sensor mounted on the holder. ### Claim 8 (depends on 7) The digital camera module as claimed in claim 7, wherein an outer periphery wall of the barrel defines a groove, and the electrode is received and is adhered in the groove. ### Claim 9 (depends on 7) The automatic focusing structure as claimed in claim 7, wherein the piezoelectric actuator includes an insulative layer and a piezoelectric ceramic material covering the insulative layer. ### Claim 10 (depends on 7) The digital camera module as claimed in claim 7, wherein the holder includes a holder body and a flange, the holder body is a hollow cylinder, and the flange is a long cube. ### Claim 11 (depends on 10) The digital camera module as claimed in claim 10, wherein the flange defines a rectangular cavity, and the rectangular cavity communicates with the holder body. ### Claim 12 A digital camera module comprising: a lens holder including a resistor thereon; a lens barrel telescopically received in the lens holder, the lens barrel having a front end and an opposite rear end, at least one lens fixed in the lens barrel, an electrode located on an outer periphery wall of the barrel, the electrode slidably contacting with the resistor, when the barrel slides relative to the holder, the resistance value of the resistor is changed, information of the resistor corresponds to a position information of the barrel; an image sensor located facing the rear end of the lens barrel; and a piezoelectric actuator attached to the rear end of the lens barrel, the position information of the barrel being fed back to the piezoelectric actuator, the piezoelectric actuator being configured for moving the lens barrel by piezoelectric deformation thereof when the piezoelectric actuator is energized. ### Claim 13 (depends on 12) The digital camera module of claim 12, wherein the piezoelectric deformation includes axial lengthening or shortening. ### Claim 14 (depends on 12) The digital camera module as claimed in claim 12, wherein the piezoelectric actuator includes an insulative layer and a piezoelectric ceramic material covering the insulative layer. ### Claim 15 (depends on 12) The digital camera module as claimed in claim 12, wherein the holder includes a holder body and a flange, the holder body is a hollow cylinder, and the flange is a long cube. ### Claim 16 (depends on 15) The digital camera module as claimed in claim 15, wherein the flange defines a rectangular cavity, and the rectangular cavity communicates with the holder body. ### Claim 17 (depends on 12) The digital camera module as claimed in claim 12, wherein the outer periphery wall of the barrel defines a groove, and the electrode is received in and adheres to the groove. ### Claim 18 (depends on 12) The digital camera module as claimed in claim 12, wherein the holder defines a notch, and the resistor is received in the notch. ### Claim 19 (depends on 12) The digital camera module as claimed in claim 12, wherein the electrodes and the resistors further connect with an anode and a cathode of a power source for providing the movement position of the lens module to the piezoelectric actuator, and the piezoelectric actuator further adjusts the position of the lens module.