Patents by Inventor Han-Ku Chu

Han-Ku Chu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Photomask for measuring lens aberration, method of its manufacture, and method of its use
    Publication number: 20060216616
    Abstract: A photomask for measuring lens aberration, a method of manufacturing the photomask, and a method of measuring lens aberration using the photomask are provided. In an embodiment, the photomask includes a transparent substrate having first and second surfaces. A reference pattern group and an encoded pattern group are formed on the second surface of the transparent substrate, spaced apart from each other. An aperture that includes a Fresnel zone is formed to face the second surface on the second surface of the transparent substrate. Light throughput and measurement efficiency are improved.
    Type: Application
    Filed: March 23, 2006
    Publication date: September 28, 2006
    Inventors: Jang-Ho Shin, Han-Ku Chu, Sang-Gyun Woo, Suk-Joo Lee