| 摘要 |
PURPOSE:To simplify the construction of a device, by constituting a beam radiation window with a grating lens. CONSTITUTION:A semiconductor layer chip 1 is arranged at the bottom of a cylindrical semiconductor laser case 10 whose inner part is air-tightly constituted. When travelling outwards from the case 10, a laser beam 2 radiated from the front end of the chip 1 passes through a circular radiation window 3 formed on the front surface. This radiation window 3 is constituted of a grating lens which acts as a convex lens, and arranged apart from the chip 1 by a distance equal to the focal length of the lens. Consequently, the laser beam 2 becomes a parallel beam 2' as a result of passing through the radiation window 3, and then radiated outwards. Thus it is unnecessary to install a special collimator lens outside the case, which simplifies the construction. |
