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[仪器仪表制造业,公共管理、社会保障和社会组织] [2020-03-10]
[计算机、通信和其他电子设备制造业,仪器仪表制造业] [2019-06-11]
[仪器仪表制造业] [2019-04-22]
[仪器仪表制造业] [2018-03-16]
[仪器仪表制造业,电气机械和器材制造业,计算机、通信和其他电子设备制造业] [2017-09-12]
Laser refers to light amplification by stimulated emission of radiation, which produces a coherent, collimated, and monochromatic beam of light by exciting atoms to a higher energy level. Lasers are distinguished from other light sources by their coherence. Spatial coherence property of laser enables it to stay narrow over great distances and allows it to be focused on a tight spot. As a result of these properties, they are widely used in applications such as laser pointers, laser cutting, and lithography. Lasers are classified based on the type of lasing medium they use such as gas, optical fiber, solid state, and semiconductor.
[电气机械和器材制造业,仪器仪表制造业] [2013-11-22]
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[计算机、通信和其他电子设备制造业,仪器仪表制造业,信息传输、软件和信息技术服务业] [2013-08-30]
[仪器仪表制造业] [2013-05-27]
[仪器仪表制造业] [2013-05-16]
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