| 摘要 |
A laser-diode assembly for generating a frequency-stabilized narrow-bandwidth light comprises a light source in the form of a semiconductor laser diode coupled via a first optical coupling device to one end of a first optical fiber. The other end of this fiber is coupled to a second or an output fiber via a second optical coupling device. The assembly is characterized by the fact that a long inner cavity is formed by a section of the optical system between two oppositely directed mirrors. The first mirror is applied onto the back side of the semiconductor laser diode, and the second mirror is applied onto a flat front side of one optical lens element or onto the back side of another optical lens element. These optical lens elements are parts of an optical coupling between the first and the second fibers. The first mirror completely reflects the entire light incident onto this mirror, whereas the second mirror reflects a major part of the light, e.g., about 90% and passes only a small part, e.g., 10% of the light incident onto this mirror. The Bragg grating is designed so that, in combination with the laser cavity L, it suppresses the side modes of the wavelength bands and transforms them into the central mode of the narrow wavelength band which can be passed through this grating. The light processed by the Bragg grating is passed through the second mirror to the output fiber, while the reflected light performs multiple cycles of reflection between both mirrors which thus form a laser resonator which amplifies the laser light output at the selected narrow waveband.
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