• Journal of the Semiconductor & Display Technology
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• v.6 no.3
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• pp.65-70
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• 2007

A method to focus the object in camera system by applying the Hill climb algorithm from optical lens moving device (VCM; Voice coil motor) is proposed. The focusing algorithm from VCM is focus on the object but in these criteria is a well-known drawback; the focus is good only at same distance objects but the focus is bad (blur image) at different distance objects because of the DOF (Depth of focus) or DOF (Depth of field) at the optical characteristic. Here, the new camera system that describes the Reflector of free curvature systems (or Diffractive Fresnel lens) and the partition of focusing window area is proposed. The method to improve the focus in all areas (different distance objects) is proposed by new optical system (discrete auto in-focus) using the Reflector of free curvature systems (or Diffractive Fresnel lens) and by applying the partition of all areas. The proposal is able to obtain good focus in all areas.

• Transactions of the Society of Information Storage Systems
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• v.7 no.2
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• pp.75-79
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• 2011

Recently mobile phone camera become generally spread, it is required to develop high resolution, multi-functional camera module for obtaining high image quality. To satisfy this demand, number of pixels has been increased and pixel size decreased in small mobile phone cameras. As a result, image quality is seriously dropped by blur phenomena. Especially when hand tremble is occurred, image quality is dropped by camera shake. Therefore, to obtain high quality image, it is necessary to compensate user's hand tremble. In this paper, we propose voice coil actuator for compensating hand tremble, which can apply optical image stabilization (OIS) system. Sensitivity analysis and size optimization are performed to obtain high driving force. Finally, it is confirmed that the optimized electromagnetic circuit can be applied in OIS system.

• Journal of the Optical Society of Korea
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• v.15 no.1
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• pp.52-55
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• 2011

We discuss the effect of stray light on a high-precision camera in an LEO(Low Earth Orbit) satellite. The critical objects and illumination objects were sorted to discover the stray light sources in the optical system. Scatter modeling was applied to determine a noise effect on the surface of a detector, and the relative flux of a signal and noise were also calculated. The stable range of reflectivity of the beam splitter was estimated for various scattering models.

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.155-156
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• 2009

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.206-207
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• 2001

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.210-211
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• 2001

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.133-134
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• 2008

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.467-468
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• 2006

• The Optical Journal
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• v.3 no.11 s.11
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• pp.64-67
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• 1991

• Proceedings of the Optical Society of Korea Conference
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• 1998.08a
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• pp.178-179
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• 1998