DEAR ALL,
嘩, 我就0黎發顛, 真係唔好講笑, 當年會考就係飲恨PHYSICS, 得個E! 救命, 如果唔係Simon大step by step咁寫...我都唔知係mug.
雖然我十分尊重MKHo大的決定, 但我都係比較心急的人, 我亦開始估到Simon大的膽心提議了, 並會影響我們LED的試驗, 容許我回應Simon大的兩句:
除了critical angle的問題...以下幾點, 我估都會影響luminous intensity都幾大 (有錯請指教).
1. 由於我們多數鼓勵用"反光板", 光管在"魚缸底部的照度"應該會大大增加.
2. 一般的光管的效能會很快下降
3. 我留意到Simon大的Link (
http://www.taiwan-ampolla.com/html/gyzs_tra.htm ) 中一句: "當節能燈用于有水或潮濕的環境下時,燈的周圍及內部就會有水或水蒸氣。一是會引起燈頭生鏽而接觸不良", 這樣會唔會又影響"照度效能"呢?
想到現在, 又有點心灰了...@@
再補充一些:
- "A bare light bulb placed above the water surface will have most of its emission lost outside the water, due to the lack of a reflector, to the critical angle at the air/water interface, and to partial reflection at that interface. For a fluorescent tube placed parallel and near the water surface, we can estimate the loss due to these factors to be of the order of 75%. That is, only about 25% of the light that leaves the bulb makes its way into the water. Adding a reflector increases that efficiency considerably. Lets assume that the PC fixture reflector can divert about 50% of the escaping light back into the water. Lets presume that the the single fluorescent strip reflector can divert back 30%. Bear in mind that all these factors are very crude approximations of the real situation.
(source from:
http://www.aquabotanic.com/lightcompare.htm)
aquabotanic.com指出只有25%光係留在水中...死未?!
- 再看看這篇
http://www.thekrib.com/Lights/depth.html#6
他們有類似的實驗(雖然他們用shoplight, 但我估差不多), 他指出"From 0 to 10 cm, the intensity dropped by half.", 這我們的LED實驗結果有點不相似. 還有最有趣的是: 當"Light Intesity in Air" vs. "Light Intesity in Water (test above tank)", Luminous Intesity因玻璃的reflection而上升.
又有一點, Aquatic Plant Central的Gomer大曾經提醒我一樣野說: 一般的螢光燈是會不停地閃, 所以光照"不是100% of time"! 但LED是"100% of time". 所以假設如果在同一個Luminous Intesity, 理論上, LED是比螢光燈強!
tklm,
係wor, "PL管做目標,照度太高了". 唔記得tim @@ T5HO/T5弱DD, 以他為目標好嗎? 但... heheeeee...容許我貪心DD, 試埋佢, 最好試埋HQI tim wor.......heheeeeee, 起碼有個reference, in case, 現在唔得, 將來都可以參考下嗎.... ^^"
老實說, 我都不太強求ideal spectrum (因為除了植物管, 其實冇一隻燈的spectrum係正野), 但try my best la.
MKHo大的LED Module幾係2" x 2", tklm, 如果個light box係2" x 2"會唔會太細ar? 如果係2" x 4"呢? 2" x 6"? 4" x 4"? 還是其他dimension好d ar? (Aquatic Plant Central的實驗tank係4"x5"x6".)
MKHo,
比你玩死 @@
我呢D small potato怎能擔如此重任ar? 唔好講笑. 隨緣la......
hoho...我可以借玩"秘密武器"ar? 我好百厭ga wor... 怕弄壞喔... hehe...但如果你在傍監視著, 我就想八下wor...hehe.
wow 鴨記燈膽$55真係好平, 但我估在效能上只是平平, 而且從相中看出很偏藍呢! 記得Top Century曾經告訴我, 鴨記的LED燈膽雖然很平, 但行DC, 而且好唔stable. 而且spectrum是"亂七八糟"的...一批批唔同spectrum...不過唔知有冇hard sell la. anyway, check check sin la....hehe...好心急! THANK YOU VERY MUCH!!!!
ps.
- 你果間野d老闆, 我一早令教過la.... 都邊個係"廢人"? 心裡有數la... 做到野的, 邊個都唔係"廢人". 我部門d人好鬼百厭ga ma, 個ar head比我地玩死ga! 唔好灰心. 努力la! 但話時話, 你間野d system好亂lor, 仲地震mei? ai~
- hehe...你gum多大計, 幾時分享ar? 我覺得它們對今次的實驗會都好有用呢~ (hehe...sorry...我又心急la)
係ar... 係ar...
實驗計劃...!
1. tank size ? height?
2. target light source?
3. target plant(s)?
4. target life span?
5. target penetration power?
6. the rate of water evaporation
仲有冇其他野miss左?
還有, 煩請其他對各種草性有熟悉的朋友, 給一些建議, 看看那種草做實驗會比較好.
( 現在, 最大問題係, 細缸水質控制很困難呢~ )
最後, 我很感謝大家的回應, 使我最近brainstorm得好快, 快招架不住了!