| 摘要 |
<p>An improved external cavity laser apparatus (20) is disclosed whereby instead of a collimated beam being aligned with a flat mirror, the collimated beam is directed at a retro-reflecting lens (10). The front (12) of the lens includes a focusing lens function and a rear (13) of the lens is coated with reflective material. The collimated beam is then focused at the rear of the lens where it is reflected back towards the tuning elements, collimating lens and gain medium (22) of the external cavity laser. Alignment tolerances for the retro-reflecting lens are greatly relaxed as compared to a flat mirror device. As a result, manufacturing external cavity lasers is facilitated, tooling costs are reduced and throughput is increased and reliability of the resulting device is increased as misalignment during the useful life of the resulting device is reduced or eliminated.</p> |
