1996 Fiscal Year Final Research Report Summary
Study on artificial anisotropic optical films composed of slanted numerous fine dielectric columns
| Project/Area Number |
07455153
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
情報通信工学
|
|---|
| Research Institution | Utsunomiya University |
|---|
Principal Investigator |
SHIRAISHI Kazuo Utsunomiya Univ., Eng.Fac., Prof., 工学部, 教授 (90134056)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MATSUMURA Kazuhito Utsunomiya Univ., Eng.Fac., Prof., 工学部, 教授 (70005297)
|
|---|
| Project Period (FY) |
1995 – 1996
|
| Keywords | oblique deposition / polarizer / walk-off polarizer / porous silicon / filling factor / optical communication / column / vacuum evaporation |
|---|
| Research Abstract |
For applications to optical devices, such as polarization-independent optical is olators and free-space optical interconnections, spatial walk-off polarizers are important components for splitting an optical beam into two orthogonally-polarized parallel beams. Both large beam-split angles and wide apertures are preferable for practical applications.
A new fabrication method of spatial walk-off polarizers that utilizes form-birefringence in an obliquely deposited thick silicon film has been proposed and experimentally verified. The film is composed of two substances, slant needle-like silicon microcolumns and resultant fine voids around them. The structure has the uniaxial birefringence whose optic axis is parallel to the column/void axis. We tried to fabricate the film by use of an electron-beam excited evaporation method. An oblique deposition technique was used to fabricate slanted numerous fine columns/voids. To assist formation of columnar microstructures, argon gas was introduced during the evaporation process ; pressure of the gas in the chamber was 0.2mTorr. We find that clear columnar microstructures can be appeared after chemical etching of the film.
The spatial walk-off characteristic has clearly been observed, and the maximum polarization-split angle in the film is measured to be 10ﾟ,being two times larger than that of existing polarizers such as those made of rutile and calcite. We have successfully performaed the research.
|
