UC知道急求翻译！谢绝机械翻译！
来源：百度知道 编辑：UC知道 时间：2024/05/06 08:35:19
For laser oscillation to occur, the laser gain---the increase in the intensity of the light as it passes through the laser medium---must exceed the loss of beam intensity caused by imperfections in the mirrors and other factors. This requirement is known as the laser threshold condition. Convent The laser uses an energy source---an electrical discharge, for example--to raise the active atoms from the lower-energy state to the excited state. But excited atoms do not remain excited indefinitely: their natural tendency is to drop back to the lower-energy state. When they do, they emit light in random directions, a process called spontaneous emission.
A small proportion of this light, typically a few millionths, heads toward one of the mirrors and is reflected back to the laser medium. The reflected light induces the excited atoms to emit additional photons with the same wavelength, direction and phase.
.This production of light with the same characteristics as the original lig
A small proportion of this light, typically a few millionths, heads toward one of the mirrors and is reflected back to the laser medium. The reflected light induces the excited atoms to emit additional photons with the same wavelength, direction and phase.
.This production of light with the same characteristics as the original lig
激光振荡发生，激光增益---增加强度的光穿过激光介质---必须超过损失束流强度不完善所造成的反射镜及其他因素。这一规定被称为激光阈值条件。修道院的激光利用能源---一个放电，例如-提高积极原子从低能量状态的激发态。但是，兴奋原子仍然兴奋不无限期：其自然的趋势是回落到较低的能量状态。当他们这样做，他们发光随机方向，这个过程被称为自发辐射。
一小部分有鉴于此，通常几百万分之一，走向一个后视镜和反映回到激光介质。反射光诱导激发原子发射出更多的光子的波长相同，方向和阶段。
。此生产轻型具有相同特征的原始轻，所谓受激发射，负责许多特殊性能的激光辐射。由于反射光之间来回反射镜，这是不断扩大的激光介质。一小部分有鉴于此是通过一个反射镜，其目的是将略少于反射比其他，使熟悉的激光束出现。
激光器必须含有大量的原子或分子提供足够的增益超过损失。例如，氦氖激光发射1毫瓦的功率包含几千万亿氖原子和大约10倍之多氦原子。
根据扩增达到平衡时，约10亿光子是弹跳之间的谐振镜子。换句话说，几百万氖原子和数以千万计的氦原子，需要保持每个光子在谐振。
4.有几种方法，以减少所需的原子。一个可以限制损失的束流强度的提高反射率的反射镜，使光子被存放更长的谐振，可以建立更容易。在某些情况下，可以提高激光增益通过减少一些背景原子干涉光放大的碰撞积极原子。但在实践中，即使是最有效的常规激光器至少需要10万原子每光子储存在谐振。显然，传统的激光不能产生束只有一个原子