檢視幾何光學及混合光經稜鏡色散再複合的原始碼

<font size="6">光的折射與色散</font>


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<font color="blue">實驗材料: </font>
<table border="1">
<tr>
<td>品名</td><td>規格</td><td>說明 </td><td>數量 </td><td>單位 </td>
</tr>
<tr>
<td>R、G、B雷射筆 </td><td>外型尺寸盡量相同 </td><td>持續開啟時間盡量長，品質穩定 </td><td>各1 </td><td>支</td>
</tr>
<tr>
<td>雷射筆支架 </td><td>能將三支雷射筆固定在同一直線，雷射筆之間距離約1.2cm。最底下雷射筆距離底座約5cm。 </td><td>三支雷射筆必須要能個別微調指向角度 </td><td>1</td><td>個</td>
</tr>
<tr>
<td>三稜鏡 </td><td>玻璃製，稜鏡高度>12cm，三角邊長愈寬愈好，付支架。 </td><td>質地均勻無氣泡，表面平整無水波紋。 </td><td>2 </td><td>組</td>
</tr>
<tr>
<td>線狀燈泡 </td><td>12V100W，含燈座 </td><td>https://world.taobao.com/item/19271109059.htm?spm=a21wu.10013406-tw.0.0.e793d28dTtZrBV </td><td>1</td><td>個</td>
</tr>
<tr>
<td>燈泡座、電線及開關 </td><td>電線長至少1m，配合鹵素燈使用 </td><td>鹵素燈泡、燈泡座、變壓器需能搭配使用 </td><td>1</td><td>個</td>
</tr>
<tr>
<td>變壓器 </td><td>120V轉12V，功率150W以上 </td><td>鹵素燈泡、燈泡座、變壓器需能搭配使用 </td><td>1</td><td>個</td>
</tr>
<tr>
<td>量角器 </td><td>一般</td><td></td><td>1</td><td>個</td>
</tr>
<tr>
<td>直尺 </td><td>60cm以上</td><td></td><td>1</td><td>支</td>
</tr>
<tr>
<td>圓規 </td><td>一般</td><td></td><td>1</td><td>支</td>
</tr>
<tr>
<td>壁報紙 </td><td>淺色半開 </td><td></td><td>1</td><td>張</td>
</tr>
</table>

</div>

==1.教學目標：  ==
*學習司乃耳折射定律及折射率定義 

*了解折射率除了與介質種類有關之外也與光的顏色(波長/頻率)有關 

*了解色散的成因並能進而演繹思考混合光經過兩個反置的三稜鏡折射後方向不變，但因不同色光橫向位移不同而形成最後折射出之複合光邊緣有不同色彩之現象。 

<br><br>
==2.教學流程： ==

*反射與折射探究式教學[分組實作討論](1.5h) 
*#以雷射光照射三稜鏡，紀錄光徑。  
*#*操作：在略遮光中以雷射光束照射三稜鏡，紀錄周圍光徑。 
*#<img style="width:30%;" src='https://upload.wikimedia.org/wikipedia/commons/f/f9/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%881.png'/>
*#探討光傳播到不同介質產生的現象 
*#判斷光束在稜鏡內的光徑，以直尺作圖連接稜鏡外的光徑。 
*#測量光徑與法線夾角，探討角度之間的關係 
*#發表討論 
<br><br>

*反射定律與折射現象(0.5h) 
*#說明(複習)反射定律並驗證 
*#引導以圓規作圖分析射過程夾角正弦函數之關係 
*#比較每一次折射過程入射角與折射角正弦函數值(或倒數)之比值是否一致。 
*#說明折射現象 
*#<img style="width:30%;" src='https://upload.wikimedia.org/wikipedia/commons/2/21/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%882.png'/>
*折射率定義與折射定律(2h) 
*#以水稜鏡測量雷射光束折射現象並分析夾角正弦函數關係 
*#以玻璃或透明壓克力製作三角柱，內部裝水成為水三稜鏡。重複以上觀測分析，比較入射角與折射角正弦函數值(或倒數)之比值與玻璃折射比值是否相同。 
*#說明折射率及司乃耳定律 
*#說明不同物質折射角度不同，定義折射率表示，並說明司乃耳定律。 
*#折射範例講解與練習 
*#作示意圖及理論推導 
*#光由空氣進入不同介質之折射角度比較 
*#光經過多層平行介質之折射角度比較 
*#光經過平板玻璃之橫向位移 
*#光經過不平行兩界面(如三稜鏡)之偏向角 
*#從理論值畫出精確的折射過程 
*#評量 
*探討全反射現象(1h) 
*#根據雷射光照射三稜鏡實驗的觀測紀錄，探討「消失的穿透光線」 
*#(在雷射光束照射三稜鏡實驗中，可能會因入射角度不同而出現全反射，此現象會造成學生疑惑，正可於學過折射定律之後提出討論。) 
*#說明全反射現象 
*#以雷射光通過垂直兩界面(玻璃磚或水族箱)觀察全反射現象 
*#說明光纖之設計原理及應用 
*由色散探討波長與折射率關係(1h) 
*#演示一束混合光經過一個三稜鏡的色散現象，引導思考成因 
*#說明混合光包含許多不同波長光，色散現象說明了不同波長的光折射率不同 
*#<img style="width:60%;" src='https://upload.wikimedia.org/wikipedia/commons/7/7c/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%883.png'/>
*#操作：在遮光環境演示光束經三稜鏡折射後投射在光屏上產生連續光色散現象 
*根據前面所學光的色散概念探討紅、綠、藍混合光經過兩個反置三稜鏡折射後的復合問題(2h) 
*#探究問題 
*#*太陽光經三稜鏡產生色散，說明了太陽光是許多色光的混合光。色散之後的色光經另一個倒置的三稜鏡能否復合回原來的太陽光(混合光)? 
*#*<img style="width:60%;" src='https://upload.wikimedia.org/wikipedia/commons/d/d5/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%884.png'/>
*#*以紅、綠、藍單色光之混合光束為代表作圖並探討。 
*#學生畫下光徑圖 
*#學習單：印妥兩個反置的大三稜鏡及代表紅、綠、藍混合之入射光束 
*#學生發表光徑圖並討論 
*#投射學生畫的學習單並進行發表及討論 
*#學生於討論後再畫下光徑圖 
*#學習單：同上 
*#教師演示並解說 
*#*教師巡視學生作圖情形 
*#*教師演示紅、綠、藍雷射光束以相同入射角平行照射第一個三稜鏡，再經一個倒置三稜鏡折射後投射在白色屏上情形 
*#*學生觀察並比對光徑圖，討論、檢討。 
*#*教師口頭說明回饋學生作答情形 
*#評量：評量學生能否由以上三種色光折射情形推論太陽光光束經過兩個反置三稜鏡折射後的復合情形，並推論各項變因(狹縫寬度、兩個三稜鏡距離等)對邊緣顏色寬度等性質的影響 
*#*一束太陽光經三稜鏡產生色散，再經另一個倒置的三稜折射後的光線照射在白色屏上是甚麼樣圖像? 
*#*改變太陽光束寬度，照射在白色屏上的圖像如何改變? 
*#*改變兩個三稜鏡距離，照射在白色屏上的圖像如何改變?
*#*<img style="width:60%;" src='https://upload.wikimedia.org/wikipedia/commons/f/f5/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%885.png'/>

<br><br>
==3.參考資料：  ==

*https://lecdem.physics.umd.edu/n/n1/n1-21.html 

<img style="width:60%;" src='https://upload.wikimedia.org/wikipedia/commons/b/b3/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%886.png'/>

*https://lecdem.physics.umd.edu/n/n1/n1-22.html 

*https://lecdem.physics.umd.edu/n/n1/n1-23.html 

*https://lecdem.physics.umd.edu/n/n1/n1-09.html 

<img style="width:60%;" src='https://upload.wikimedia.org/wikipedia/commons/b/b0/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%887.png'/>

*https://lecdem.physics.umd.edu/n/n1/n1-08.html 

*https://lecdem.physics.umd.edu/n/n1/n1-13.html 

<img style="width:30%;" src='https://upload.wikimedia.org/wikipedia/commons/7/73/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%888.png'/>

*Additional Info 

*ID Code:N1-21 

*Purpose:Show how a prism can recombine previously dispersed white light. 

*Description:The prismatic spectrum setup of demonstration N1-01: PRISMATIC SPECTRUM OF WHITE LIGHT - POINT SOURCE is used to create a white light prism spectrum, seen in the photograph in the center. A second identical prism is then positioned in the beam with the base opposite that of the dispersing prism, so that the colors are recombined into a white spot. 

*Availability:Available 

*References:REFERENCES: (PIRA 6F10.35) 

*Read 1998 times 

*Published in N1 Continuous Spectra 

*More in this category: « N1-14: REFLECTION GRATING - LARGE N1-22: OPTICAL BOARD - PRISMS - SEPARATE AND RECOMBINE » 

<img style="width:30%;" src='https://upload.wikimedia.org/wikipedia/commons/1/14/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%889.png'/><br><br>
<img style="width:60%;" src='https://upload.wikimedia.org/wikipedia/commons/7/76/%E5%B9%BE%E4%BD%95%E5%85%89%E5%AD%B8%E5%8F%8A%E6%B7%B7%E5%90%88%E5%85%89%E7%B6%93%E7%A8%9C%E9%8F%A1%E8%89%B2%E6%95%A3%E5%86%8D%E8%A4%87%E5%90%8810.png'/>


*Additional Info 

*ID Code:N1-22 

*Purpose:Separate white light into its component colors with a prism and use an identical prism to recombine the light. 

*Description:Use the optical board with a single slit baffle and a convex lens to limit the size of the ray. The single ray is passed through a prism which separates the light into its component colors, which can be cast onto a white surface. Placing a second identical prism in the beam in the opposite orientation recombines the colors into a white light spot and directs the light in a ray parallel to the original ray. 

*Use a mirror to reflect the original dispersed light onto the screen, then move the support to the left to intercept the beam with the second prism, which will direct the beam onto the same spot after recombining. The optical element configuration is shown at the left (one prism) and at the right (two prisms) above The resulting "spectrum" for each configuration is shown below. 

*Availability:Available 

*References:REFERENCES: (PIRA 6F10.30) 

*Read 1199 timesLast modified on Thursday, 29 October 2015 11:06 

*Published in N1 Continuous Spectra 

*Tagged under  

*PiP Oct 2015 

*More in this category: « N1-21: COLOR SEPARATION AND RECOMBINATION BY PRISMS N1-23: FINE RESOLUTION OF SPECTRUM USING TWO PRISMS »