As before, the laser package is hermetically sealed for reliable operation in adverse environments and the laser output is collimated using an internal lens system.

密封激光包在恶劣环境下可靠运行，激光输出采用内部透镜系统校准。

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The selection of parameters for miniature TEA CO2 lasers is analysed and a miniature whole metallic-sealed-off ceramic TEA CO2 laser is developed.

本文从理论上分析了小型tea CO_2激光器的参数选取，制出了实用的陶瓷壳体全金属密封的小型TEA CO_2激光器。

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Because the working media of laser is gas, and the pressure difference between the inner apparatus and environment of laser is large, so the window of output laser beam must be sealed.

由于其激光工作介质是气体，而且激光腔内的压力与外界环境压强相差很大，激光束的输出窗口必须密封。

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If needed, antibiotic paste can be inserted into the tooth through a hole made by a more powerful laser and then the tooth can be sealed.

BBC: 'No need for dentist's drill'