Many thanks to @mcw for hosting this competition and giving me a chance to learn more about science.
The details of the contest as the following link:
^{https://steemit.com/sciencepic/@mcw/christmas-science-picture-challenge-1-with-sbd-and-sp-prize-1-sbd-sp}

很多謝 @mcw 舉行這個比賽，給予一個機會，在忙碌的生活中了解多些關於科學的知識，下面是這個比賽的連結:
^{https://steemit.com/sciencepic/@mcw/christmas-science-picture-challenge-1-with-sbd-and-sp-prize-1-sbd-sp}

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The Christmas tree at skytree tokyo.

東京晴朗塔的聖誕樹。

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The tree is build by LED light, an LED lamp is an electric light or light bulb for use in lighting fixtures that produces light using light-emitting diodes (LEDs).

LED lamps have a lifespan and electrical efficiency which are several times greater than incandescent lamps, and are significantly more efficient than most fluorescent lamps, with some chips able to emit more than 300 lumens per watt.

The LED lamp market is projected to grow by more than twelve-fold over the next decade, from $2 billion in the beginning of 2014 to $25 billion in 2023, a compound annual growth rate of 25%. As of 2016, LEDs use only about 10% of the energy an incandescent lamp requires. [source by wiki]

整棵樹是由LED燈組成的，LED燈是指利用發光二極體作為光源的燈具，一般使用半導體LED製成。

發光二極體是一種能發光的半導體電子元件，透過三價與五價元素所組成的複合光源。及後發展出其他單色光的版本，時至今日，能夠發出的光已經遍及可見光、紅外線及紫外線，光度亦提高到相當高的程度。

LED燈的壽命和發光效率可達白熾燈的幾倍，和一體式螢光燈相比也高出不少。 單顆發光二極體的光度比傳統白熾燈和省電燈泡低很多，所以一個燈泡通常會包含多顆發光二極體。[Source by wiki]

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Here also have a Music Challenge, come to join too! !!這裡也有音樂挑戰，也來參加吧！

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