Simple estimate is to pass the light spot diameter is 2 times or more.

简单的估计，是让通光直径是光斑的2倍或以上。

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The laser spot diameter and its intensity distribution are measured with a scanning pinhole.

利用针孔扫描的原理，测量了聚焦光斑尺寸及光斑内的能量分布状况。

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Good beam quality, close to the basement membrane, small spot diameter, perfect for ultra-fine marking.

光束质量好，接近基膜，光斑直径小，完美适用于超精细标记。

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The 1.8m (60-inch) diameter telescope on Haleakala will also spot many small, faint bodies in the outer Solar System that hid from previous surveys.

BBC: Pan-Starrs telescope begins operations to hunt asteroids