The observation lens is the single-tube visual lens, eyeglass is made of a concave lens, and the inner part of a lens tube is provided with a visual distance increasing device.

所述的观测镜是单筒目视镜，目镜用凹透镜制成，镜筒内部设有视距增长装置。

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The apparatus consists of the standard color plate, optical lens, the light source was observed, colorimetric tube.

本仪器由标准色盘、观察光学镜头、光源、比色管组成。

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Because the power stable, selection of long life laser tube and import lens combination, make ZT series shake the machine service life and reliability is greatly increased.

由于选配了功率稳定、超长寿命的激光管和进口镜片组合，使得ZT系列刻章机寿命和可靠性大大提高。

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The earliest versions were simply glass lens fitted into a tube.

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Then your doctor uses a thin tube equipped with a camera lens and light (laparoscope) to view the area.

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