Abstract:
A zoom function system is disclosed. The zoom function system includes an upper lens assembly, a lower lens assembly, an upper actuator, and a lower actuator. The upper and the lower actuators have stationary elements and movable elements. The upper lens assembly is attached to one of the movable elements of the upper actuator. The lower lens assembly is attached to one of the movable elements of the lower actuator. The zoom function system allows three degrees of freedoms of translational adjustments of lens assemblies and is capable of realigning the lens assemblies to improve the qualities of images.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent application claims benefit of a provisional patent application 62/100,773 filed on Jan. 7, 2015. The disclosure made in the provisional patent application 62/100,773 is hereby incorporated by reference. This Patent Application is a Continuation in Part (CIP) Application of a pending application Ser. No. 14/970,538 filed on Dec. 15, 2015 by having a common inventor. The Disclosure made in the patent application Ser. No. 14/970,538 is hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates generally to a zoom function system of a camera module. More particularly, the present invention relates to a zoom function system allowing three degrees of freedoms of translational adjustments of lens assemblies. 
       BACKGROUND OF THE INVENTION 
       [0003]    Zoom function is now a standard function in miniature cameras. There is a constant need to improve performance of zoom function. It is advantageous to extend the zoom function technology to include more degrees of freedoms of translational adjustments of lens assemblies. 
       SUMMARY OF THE INVENTION 
       [0004]    This invention discloses a zoom function system that allows three degrees of freedoms of translational adjustments of lens assemblies. The zoom function system includes an upper lens assembly, a lower lens assembly, an upper actuator, and a lower actuator. The upper and the lower actuators have stationary elements and movable elements. The upper lens assembly is attached to one of the movable elements of the upper actuator. The lower lens assembly is attached to one of the movable elements of the lower actuator. Blurred images may be induced by misalignment of lens assemblies or off optical axis motion of lens assemblies during zooming process. The capabilities of the three degrees of freedoms of the translational adjustments of lens assemblies may re-align the lens assemblies and improve the qualities of images. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a schematic perspective view of a zoom function system in examples of the present disclosure. 
           [0006]      FIG. 2  is a bottom view of the zoom function system of  FIG. 1 . 
           [0007]      FIG. 3  is a cross-sectioned view of another zoom function system in examples of the present disclosure. 
           [0008]      FIG. 4  is a schematic perspective view of an actuator in examples of the present disclosure. 
           [0009]      FIG. 5  is an exploded plot of the actuator of  FIG. 4 . 
           [0010]      FIG. 6  is a top view of the actuator of  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0011]      FIG. 1  is a schematic perspective view of a zoom function system  100  in examples of the present disclosure.  FIG. 2  is a bottom view of zoom function system  100  of  FIG. 1 . As shown in  FIG. 1  and  FIG. 2 , zoom function system  100  includes an upper lens assembly  120 , a lower lens assembly  122 , an upper actuator  1100  and a lower actuator  2100 . Upper actuator  1100  includes one or more upper stationary elements  1500 , a first upper translation element  1200  to translate along X direction, a second upper translation element  1300  to translate along Y direction, and a third upper translation element  1400  to translate along Z direction. Lower actuator  2100  includes one or more lower stationary elements  2500 , a first lower translation element  2200  to translate along X direction, a second lower translation element  2300  to translate along Y direction, and a third lower translation element  2400  to translate along Z direction. Upper lens assembly  120  is attached to first upper translation element  1200  of upper actuator  1100 . Lower lens assembly  122  is attached to first lower translation element  2200  of lower actuator  2100 . 
         [0012]    In examples of the present disclosure, the translations of translation elements  1200 ,  1300 ,  1400 ,  2200 ,  2300 , and  2400  may be driven by electrostatic comb drives. 
         [0013]    In examples of the present disclosure, upper lens assembly  120  moves along positive X direction when first upper translation element  1200  translates a positive displacement along X axis. Upper lens assembly  120  and first upper translation element  1200  move along positive Y direction when second upper translation element  1300  translates a positive displacement along Y axis. Upper lens assembly  120 , first upper translation element  1200 , and second upper translation element  1300  move along positive Z direction when third upper translation element  1400  translates a positive displacement along Z axis. 
         [0014]    In examples of the present disclosure, lower lens assembly  122  moves along positive X direction when first lower translation element  2200  translates a positive displacement along X axis. Lower lens assembly  122  and first lower translation element  2200  move along positive Y direction when second lower translation element  2300  translates a positive displacement along Y axis. Lower lens assembly  122 , first lower translation element  2200 , and second lower translation element  2300  move along positive Z direction when third lower translation element  2400  translates a positive displacement along Z axis. 
         [0015]    In one example, upper lens assembly  120  includes a single lens and lower lens assembly  122  includes a single lens. In another example, upper lens assembly  120  includes a barrel and lower lens assembly  122  includes a barrel. 
         [0016]    In examples of the present disclosure, zoom function system  100  may further include one or more lens assemblies. In examples of the present disclosure, zoom function system  100  may further include one or more lens assemblies and one or more actuators. Each of the one or more lens assemblies is attached to one of the one or more actuators. 
         [0017]    In examples of the present disclosure, a camera module may include zoom function system  100  and an autofocus system disclosed in U.S. 62/096,854. 
         [0018]      FIG. 3  is a cross-sectioned view of another zoom function system  300  in examples of the present disclosure. Zoom function system  300  includes an upper lens assembly  320 , a lower lens assembly  322 , a mid-range lens assembly  324 , an upper actuator  3100 , a lower actuator  4100 , and a mid-range actuator  5100 . A first set of solder balls  360  may connect mid-range actuator  5100  and upper actuator  3100 . A second set of solder balls  380  may connect mid-range actuator  5100  and lower actuator  4100 . 
         [0019]      FIG. 4  is a schematic perspective view of an actuator  1100  (upper actuator  1100  of  FIG. 1 ) in examples of the present disclosure. Actuator  1100  includes one or more stationary elements  1500 , a first translation element  1200  to translate along X direction, a second translation element  1300  to translate along Y direction, and a third translation element  1400  to translate along Z direction. In examples of the present disclosure, lower actuator  2100  is similar to upper actuator  1100 . 
         [0020]    In examples of the present disclosure, first translation element  1200 , second translation element  1300 , and third translation element  1400  are in cylindrical shapes and have the same central axis (Z axis). In one example, the radius of first translation element  1200  is smaller than the radius of second translation element  1300  and the radius of second translation element  1300  is smaller than the radius of third translation element  1400 . In another example, the radius of first translation element  1200  is larger than the radius of second translation element  1300  and the radius of third translation element  1400  is larger than the radius of first translation element  1200 . 
         [0021]      FIG. 5  is an exploded plot of actuator  1100  of  FIG. 4 . Actuator  1100  may include a top layer  1111  and a bottom layer  1191 . In one example, top layer  1111  is attached to bottom layer  1191 . In another example, top layer  1111  is attached to a middle layer (not shown) and the middle layer is attached to bottom layer  1191 . In examples of the present disclosure, top layer  1111  and bottom layer  1191  are made of silicon and middle layer is made of silicon oxide. 
         [0022]    Top layer  1111  may include ground electrode member  1122 , ground electrode member  1124 , ground electrode member  1126 , X-driving electrode member  1132 , X-driving electrode member  1134 , Y-driving electrode member  1142 , and Y-driving electrode member  1144 . Ground electrode members  1122 ,  1124 , and  1126  connect to ground. X-driving electrode members  1132  and  1134  connect to driving voltage potentials. Y-driving electrode members  1142  and  1144  connect to driving voltage potentials. 
         [0023]    Bottom layer  1191  may include Z-driving electrodes  1542 ,  1544 ,  1546 ,  1548 ,  1550 ,  1552 ,  1554 , and  1556 , support ring  1322 , and support ring  1422 . 
         [0024]    First translation element  1200  may be in top layer  1111 . Second translation element  1300  may include arc member  1312 , arc member  1314 , arc member  1316 , and arc member  1318  in top layer  1111  and support ring  1322  in bottom layer  1911 . Third translation element  1400  may include arc member  1412 , arc member  1414 , arc member  1416 , and arc member  1418  in top layer  1111  and support ring  1422  in bottom layer  1911 . 
         [0025]    In examples of the present disclosure, moving electrodes  1442 ,  1444 ,  1446 ,  1448 ,  1450 ,  1452 ,  1454 , and  1456  are engaged with Z-driving electrodes  1542 ,  1544 ,  1546 ,  1548 ,  1550 ,  1552 ,  1554 , and  1556  to form eight out-of-plane comb drives. 
         [0026]      FIG. 6  is a top view of actuator  1100  of  FIG. 4 . Actuator  1100  further includes X-translational springs  1282 ,  1284 ,  1286 , and  1288 , Y-translational springs  1392 ,  1394 ,  1396 , and  1398 , and one or more Z-translational springs  1591 . X-translational springs  1282 ,  1284 ,  1286 , and  1288  connect first translation element  1200  and second translation element  1300 . Y-translational springs  1392 ,  1394 ,  1396 , and  1398  connect second translation element  1300  and third translation element  1400 . 
         [0027]    Moving electrodes  1272  and  1274  extending from first translation element  1200  are engaged with X-driving electrodes  1372  and  1374  extending from second translation element  1300  to form two in-plane comb drives. Moving electrodes  1362  and  1364  extending from second translation element  1300  are engaged with Y-driving electrodes  1462  and  1464  extending from third translation element  1400  to form two in-plane comb drives. 
         [0028]    Those of ordinary skill in the art may recognize that modifications of the embodiments disclosed herein are possible. For example, the numbers of springs may vary; the springs may be linear springs, serpentine springs, or other kinds of springs; the numbers of comb drives may vary; and the numbers and the shapes of the comb teeth of the comb drives may vary. Other modifications may occur to those of ordinary skill in this art, and all such modifications are deemed to fall within the purview of the present invention, as defined by the claims.