【摘 要】
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Generally， human body could endure 0.4 m Ws of laser power. High power laser rays could damage the retina， or even cause permanent visual loss if it is used to shoot directly at the eyes. It could bur
【出 处】
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KNOWLEDGE IS POWER
论文部分内容阅读
Generally， human body could endure 0.4 m Ws of laser power. High power laser rays could damage the retina， or even cause permanent visual loss if it is used to shoot directly at the eyes. It could burn the skin if directly shoots at skins for relatively long time. Vendors selling layer pen toys are not always clear about the exact laser power. Therefore， if a consumer carelessly buy a laser pen of high power and use it to shoot at him/herself or others， it could damage the eyes. Therefore， we advise you to be careful while playing with laser pens.
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