TA的每日心情 | 开心 2014-12-28 17:33 |
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签到天数: 1 天 [LV.1]初来乍到
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汗,真的上了CPF了.
不管怎么说国货也是要支持的,在自己家里讨论一下也就算了,发到CPF就不怀好意了
Does Jetbeam use real sapphire crystal lens?
http://www.candlepowerforums.com/vb/showthread.php?t=210905
Does Jetbeam use real sapphire crystal lens?
Jetbeam has always claimed that their flashlights use sapphire crystal lenses. But I just heard that after their first batches made in 2004, they have stopped using sapphire crystal. What they’ve been using is a kind of optical glass used for cheap watches.
On a flashlight the lens isn’t as important as the LED, or the reflector, or the circuit. But JB has always touted their lens material, and if you’re like me, “sapphire crystal” is indeed a strong selling point because this material can hardly be scratched. So if what I heard is true, JB’s ethic would be questionable. But I can’t confirm this because I gave out my only JB a year ago. For those of you who want to find out, measuring the density of the lens can get you the answer. The density of sapphire crystal is 3.98g/cm3, while that of normal glass is 2.4g/cm3.
[ 本帖最后由 greenx 于 2008-10-25 15:35 编辑 ] |
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