摘要 |
<p>Linearly polarised laser pulses are variable attenuated by rotating or tilting a plate (20) with respect to the optical axis (10). A second plate (21) may be arranged in a symmetrical manner to compensate for offset of the pulse from the optical axis (10). A feedback system may be used to control the orientation of the plates (20, 21) to achieve the desired intensity. The plates (20, 21) may comprise uncoated glass substrate, and are suitable for attenuating high energy pulses such as those used in eye surgery.</p> |