| 摘要 |
PURPOSE:To manufacture a high-performance waveguide type lens with high reproducibility and, at the same time, at a low cost, by making the concn. of a dopant which changes the refractive index of a base plate different in the surface layer of the base plate and forming a waveguide layer and lens section. CONSTITUTION:Since a dopant which makes the refractive index of a base plate 22 higher is contained in the surface layer of the base plate in a waveguide type lens 21, a waveguide layer 23 is formed in the surface layer. The lens section 24 of this lens 21 is formed at part of the waveguide layer 23 since the part contains another dopant, whose concn. is higher than that constituting the waveguide layer 23. Since the refractive index of the lens section 24 of this waveguide type lens 21 is higher than that of the surrounding waveguide layer 23, the light propagated through the central part of the lens section 24 is delayed in phase as compared with the light propagated through the peripheral part of the lens section 24. Therefore, when parallel rays of light 25 are propagated through the waveguide layer 23, the parallel rays of light 25 are condensed by the lens section 24. |
