Miniature optical zoom lens

Abstract

Miniature zoom lens systems and methods of manufacturing thereof are described. An exemplary system includes a first prism positioned to receive incident light from an entrance to the miniature lens system, at least a first varifocal lens positioned to receive the light that exits the prism, at least one base lens positioned to receive the light after passing through the first varifocal lens, a detector positioned to receive the light after passing through the base lens, and a first actuator configured to move the first varifocal lens in at least a direction perpendicular to propagation axis of the light passing through the first varifocal lens. The miniature lens system has a small z-height and can be implemented in mobile devices such as mobile phones.

What is claimed is: 
     
         1 . A miniature zoom lens system, comprising:
 a first prism positioned on an optical axis to receive incident light from an entrance to the miniature lens system through a first face of the first prism and to bend the received light by approximately 90 degrees before allowing the light to exit from a second face of the first prism;   a pair of varifocal lenses, each comprising at least two optical elements and each optical element having at least one optical surface defined by a polynomial, and wherein at least one of the pair of varifocal lenses is positioned to receive light that exits from the second face of the prism; each of the optical elements being formed integrally with a frame,   at least one base lens positioned substantially along the optical axis to receive light after passing through the pair of varifocal lenses; and   a first actuator configured to connect to the frames of the optical elements to move the pair of varifocal lenses in a direction substantially perpendicular to optical axis.   
     
     
         2 . The system of  claim 1 , wherein the lens and frame are formed integrally by injection molding. 
     
     
         3 . The system of  claim 1 , wherein the first varifocal lens is one of the following: a liquid crystal lens, a liquid lens, or an Alvarez-like lens. 
     
     
         4 . The system of  claim 1  wherein at least two surfaces of at least one of the optical elements are defined by polynomials. 
     
     
         5 . The system of  claim 1 , wherein the first actuator comprises one of a coil or a magnet. 
     
     
         6 . The system of  claim 1 , further comprising a structural platform to allow one of the following to be directly molded onto, fabricated onto, or integrated with the structural platform: the first prism, a second prism, the first varifocal lens, or a second varifocal lens. 
     
     
         7 . The system  claim 6 , wherein the structural platform comprises a spring flexure element. 
     
     
         8 . The system  claim 6 , wherein the structural platform includes a frame and an arm. 
     
     
         9 . The system  claim 8 , wherein:
 the structural platform frame comprises a lead frame metal structure that is one or more of: a metal-stamped structure, a laser-cut structure, a milled structure, an etched structure, or a molded structure;   the arm is molded on the lead frame structure; and   one or more of the first prism, a second prism, the first varifocal lens, or a second varifocal lens is molded onto the lead frame.   
     
     
         10 . The system of  claim 6 , wherein a wafer-level optical component with a preformed lens element is bonded to the platform. 
     
     
         11 . The system  claim 1 , wherein the first actuator is a voice-coil actuator with a bidirectional drive. 
     
     
         12 . The system  claim 1 , comprising second actuator configured to move an optical component other than the first varifocal lens within the miniature zoom lens system. 
     
     
         13 . The system of  claim 12 , wherein the second actuator and the first actuator are configured to displace both the optical component other than the first varifocal lens and the first varifocal lens by the same distance and in the same direction. 
     
     
         14 . The method of  claim 13 , wherein the optical component other than the first varifocal lens is one of: a second varifocal lens, the at least one base lens, the first prism, or a second prism. 
     
     
         15 . The system  claim 1 , wherein the first varifocal lens has a rectangular or an oval-shaped cross section encompassing only an essential active area of the first varifocal lens. 
     
     
         16 . The system  claim 1 , further comprising a second varifocal lens positioned to receive the light exiting the first varifocal lens before reaching the at least one base lens. 
     
     
         17 . The system of  claim 16 , wherein the second varifocal lens has a rectangular or an oval-shaped cross section encompassing only an essential active area of the second varifocal lens. 
     
     
         18 . The system of  claim 16 , wherein the optical elements of both the first and the second varifocal lenses are movable with respect to one another so as to provide optical zoom capability for the lens system. 
     
     
         19 . The system  claim 1 , wherein the at least one base lens is configured to move along the optical axis of the system to provide optical focusing ability for the lens system. 
     
     
         20 . A miniature zoom lens system, comprising:
 a first varifocal lens positioned to receive incident light from an entrance to the miniature lens system, the first varifocal lens comprising at least two optical elements, each formed integrally with a frame;   a first prism positioned to receive light from the first varifocal lens through a first face of the first prism and to bend the received light by approximately 90 degrees before allowing the light to exit from a second face of the first prism;   a second varifocal lens positioned to receive the light that exits the second face of the prism, the second varifocal lens comprising at least two optical elements, each formed integrally with a frame;   at least one base lens positioned to receive the light after passing through the second varifocal lens;   a second prism positioned to receive the light that exits the at least one base lens through a first face of the second prism and to bend the light received by the second prism by approximately 90 degrees before allowing the light to exit from a second face of the second prism; and   at least one actuator configured to connect to the frames of the optical elements to move the optical elements of one or both of the first varifocal and second varifocal lenses in at least a direction perpendicular to an optical axis of the system.