Electronics and Telecommunications Research Institute

Korea Telecom

Gee Pyeong Han

Yark Yeon Kim

Kyoung Ik Cho

Sang Seok Lee

Mun Cheol Paek

Duk Jun Kim

Tae Goo Choy

Jin Woo Hahn

Yeung Joon Sohn

Tae Youb Kim

The present invention relates to an apparatus for measuring a slant angle in a solid immersion lens. In a near-field optical data storage head for storing/reading data using a solid immersion lens (SIL), a parallel light is formed within the plane of the solid immersion lens and the slant angle of the parallel light is then measured using the angle measurement principle of the autocollimator in order to measure the slant angle of the solid immersion lens. For this, the present invention includes an optical system for generating the parallel light within the solid immersion lens, and a unit for measuring the slant angle of the solid immersion lens using a location detection unit. An incident light becomes the parallel light by the optical system and the curved face of the solid immersion lens. The reflected light is also focused on the location detection unit. The location detection unit converts the reflection angle of the reflecting light into a location value to calculate the angle value.

Apparatus for measuring slant angle of solid immersion lens

The present invention relates to an optical data recording device using SIL (Solid Immersion Lens) in order to store information with high capacity, and more particularly to the multiple optical-recording apparatus capable of doing multiple information storage and play by forming multiple focus within the SIL. The present invention utilizes the optical technology by multiple source in order to overcome the limit of improving the recording speed and transfer rate due to the mechanical transfer and access, the flying head technology, which was proposed to increase the transfer rate and recording access speed in the near-field recording technology. The present invention can increase the recording speed and transfer rate using optical technology transcending the limit of mechanical transfer and access according to the number of the optical sources and focuses by recording and playing several pits simultaneously after forming multiple optical focus by multiple sources on the recording medium.

Multiple optical-recording apparatus using solid immersion lens

A dielectric ceramic composition for a microwave device including MgTiO.sub.3 and CaTiO.sub.3 as a main component and a Li.sub.2 CO.sub.3 as a sub-component is provided. The composition being expressed as follows: (94MgTiO.sub.3 -6CaTiO.sub.3)+xLi.sub.2 CO.sub.3 (mol %), where 0.2.ltoreq.x.ltoreq.0.8 (mol %). Therefore, it is capable of increasing a quality factor and decreasing a sintering temperature by adding a new component and effectively reproducing the above-described dielectric characteristic.

Dielectric ceramic composition of microwave MGTIO.sub.3 CATIO.sub.3

A microwave dielectric ceramic composition is fabricated by adding one selected from a material containing Ba and a material containing Sr or a mixture of a material containing Ba and a material containing Sr to a composition formed of 25.about.43 wt % of TiO.sub.2, 39-57 wt % of ZrO.sub.2, and 7-28 wt % of SnO.sub.2 as an additive, wherein the additive is added by 0.2.about.8.0 wt % based on the total amount of the composition, and is capable of implementing a high dielectric constant and quality factor by sintering at a temperature of 1250.about.1400.degree. C.

Microwave dielectric ceramic composition

Growing community of inventors

Daejon-Shi, South Korea

Gee Pyeong Han