| 摘要 |
PURPOSE:To obtain a Luneberg lens which has prescribed focal length by forming the Luneberg lens on a waveguide and then exposing the Luneberg lens to energy radiation until its focal length has a desired value. CONSTITUTION:On an Y-cut LiNbO3 substrate 3, a waveguide 2 is formed by diffusing Ti and on it, an AS2S3 Luneberg lens 1 is provided by mask vapor deposition. Distance C from the center of the As2S3 Luneberg lens 1 to a waveguide end surface 4 where the butt coupling of beams 6 emitted from a laser diode 5 is performed is set as the designed focal length of the AS2S3 Luneberg lens 1. To find the width of a light beam 8 emitted to the end part, a screen 9 is arranged, and while the beam width is adjusted, the AS2S3 lens is irradiated with ultraviolet rays 10. When the focal length has a desired value, the Luneberg lens may be covered with a protective coating. |
