Song B.Y.,Seoul National University |
Nam D.S.,MuTAS Inc. |
Kim J.G.,MuTAS Inc. |
Park J.S.,University of California at Los Angeles |
And 3 more authors.
Microsystem Technologies | Year: 2010
Recent cellular phones have high-resolution, compact digital camera modules that have several millions of pixels. Although being small, such several mega-pixel camera modules definitely need to be able to execute auto-focusing and/or optical zooming in order to obtain precise images. Hence, image photographing devices having driving mechanisms that can move a lens group in the direction parallel to an optical axis have appeared such as piezoelectric type, linier motor type, and voice coil motor type. Although these technologies are already popular in existing digital cameras, driving mechanism for camera modules in cellular phones needs to be extremely improved because their requirements are totally different from usual digital cameras. Compact image photographing devices, which are installed in mobile apparatuses, should improve portability by reducing their sizes and weights and increase use-time of a battery by reducing power consumption. Weakened suspension (e.g. thickness is 0.02 mm or less) in order to minimize an elastic coefficient for drastic decrease of driving current frequently occurs permanent step-out of a lens group by plastic deformation of the metal suspensions when it comes to getting shocks from accidental drops of a handset. The proposed auto-focusing actuator using conductive polyimide as a flexible diaphragm satisfies these requirements of ultra slim cell phones. This polyimide suspension shows ultimate toughness when it comes to drop-test of cell phones. This actuator also shows high performance quite enough for several mega-pixel camera modules for ultra slim cellular phones; the moving range is up to 0.35 mm, the DC sensitivity is 0.2 mm/140 mA, and the resistance at the terminal is 22 Ohm, whereas the aperture is 6.8 mm, and the overall size is 10 × 10 × 3.95 mm. Most of all, the robustness against drop and shock has been dramatically increased, with no change of reliability under high temperature and high humidity condition, because of the flexibility of the conductive polyimide suspension. © 2009 Springer-Verlag.
Samsung and Mutas Inc. | Date: 2010-10-19
A shake correction module, a camera module including the same, and a method of manufacturing the camera module are provided. The shake correction module includes: a hinge member which supports rotation movement of an optical module based on each of at least two axes at least by using an elastic characteristic of the hinge member, wherein the optical module comprises an image sensor; a base member to which the hinge member is installed; and a driving motor which rotates the hinge member based on the each of the at least two axes with respect to the base member, in order to manufacture a structure for supporting two-axes rotation of the optical module to be simple and reliable with a low manufacturing cost.
Kim C.,Yonsei University |
Song M.-G.,Yonsei University |
Kim Y.,Yonsei University |
Park N.-C.,Yonsei University |
And 5 more authors.
Microsystem Technologies | Year: 2013
There is increasing consumer's demand for high-quality and high-performance mobile imaging devices. In this paper, an auto-focusing (AF) actuator with a flexure hinge that uses the electromagnetic (EM) circuit of a voice coil motor was designed and evaluated. The flexure hinge was designed by using finite element analysis. The EM circuit was designed based on the structural stiffness of the device. The EM circuit was analyzed using the design of experiments procedure. Based on the results, the effective design parameters were selected, and improvements were made to the design. Finally, a prototype of the AF actuator was manufactured, and the feasibility and performance of the actuator with the flexure hinge were verified experimentally. The experimental results indicated that the proposed actuator performed adequately and satisfied the design requirements. © 2013 Springer-Verlag Berlin Heidelberg.