Capon M R, Docchio F, Mellerio J
Department of Clinical Ophthalmology, Institute of Ophthalmology, London, UK.
Graefes Arch Clin Exp Ophthalmol. 1988;226(4):362-6. doi: 10.1007/BF02172968.
In an ocular model plasmas were induced by Q-switched, commercially available Nd:YAG lasers that operated in low order or fundamental mode. Plasma shielding was measured and analysed in relation to energy input, number of plasmas and plasma evolution. Near breakdown threshold, attenuation or shielding of the laser beam resulting from absorption and scattering by the plasma is low and is characterized by high variability from shot to shot. More importantly, shielding does not increase when multiple plasmas are formed, possibly due to a competitive mechanism between these plasmas. Further evidence of this mechanism was obtained from measurement performed using a streak camera. The effectiveness of shielding is scarcely changed by an increase in the cone angle of the incident radiation. In the light of these experiments and other published data, safety guidelines for the clinical use of the Nd:YAG laser have been formulated.
在一个眼部模型中，通过调Q、市售的基模或低阶模运转的Nd:YAG激光器诱导产生等离子体。测量并分析了与能量输入、等离子体数量和等离子体演化相关的等离子体屏蔽情况。接近击穿阈值时，等离子体吸收和散射导致的激光束衰减或屏蔽较低，且每次发射的变化很大。更重要的是，当形成多个等离子体时，屏蔽不会增加，这可能是由于这些等离子体之间存在竞争机制。使用条纹相机进行的测量进一步证实了这一机制。屏蔽效果几乎不会因入射辐射锥角的增加而改变。根据这些实验和其他已发表的数据，已制定了Nd:YAG激光临床使用的安全指南。
