{
 "metadata": {
  "name": "",
  "signature": "sha256:3f2462cfb429298e26fc6bf563d665947cd211731889b95d7dd1a2db3452c286"
 },
 "nbformat": 3,
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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Fibre Optics"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example number 3.1, Page number 98 "
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "#importing modules\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "n1=1.6;    #refractive index of core\n",
      "n2=1.5;    #refractive index of cladding\n",
      "\n",
      "#Calculation\n",
      "NA=math.sqrt((n1**2)-(n2**2));\n",
      "NA=math.ceil(NA*10**4)/10**4;   #rounding off to 4 decimals\n",
      "\n",
      "#Result\n",
      "print(\"the numerical aperture of the fibre is\",NA);\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "('the numerical aperture of the fibre is', 0.5568)\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example number 3.2, Page number 98 "
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "#importing modules\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "n1=1.54;    #refractive index of core\n",
      "n2=1.5;    #refractive index of cladding\n",
      "n0=1;\n",
      "\n",
      "#Calculation\n",
      "NA=math.sqrt((n1**2)-(n2**2));         #numerical aperture of fibre\n",
      "NA=math.ceil(NA*10**5)/10**5;   #rounding off to 5 decimals\n",
      "alpha=math.asin(NA/n0);          #acceptance angle in radians\n",
      "alpha=alpha*57.2957795;        #converting radians to degrees\n",
      "alpha=math.ceil(alpha*10**5)/10**5;   #rounding off to 5 decimals\n",
      "deg=int(alpha);        #converting to degrees\n",
      "t=60*(alpha-deg);   \n",
      "mi=int(t);     #converting to minutes\n",
      "sec=60*(t-mi);    #converting to seconds\n",
      "sec=math.ceil(sec*10**3)/10**3;   #rounding off to 3 decimals\n",
      "\n",
      "#Result\n",
      "print(\"the numerical aperture of the fibre is\",NA);\n",
      "print(\"the acceptance angle of the fibre in degrees is\",alpha);\n",
      "print(\"acceptance angle of the fibre is\",deg,\"degrees\",mi,\"minutes\",sec,\"seconds\");\n",
      "\n",
      "#answer for the angle given in the book is wrong"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "('the numerical aperture of the fibre is', 0.34872)\n",
        "('the acceptance angle of the fibre in degrees is', 20.40905)\n",
        "('acceptance angle of the fibre is', 20, 'degrees', 24, 'minutes', 32.581, 'seconds')\n"
       ]
      }
     ],
     "prompt_number": 7
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example number 3.3, Page number 99"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "#importing modules\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "n1=1.6;    #refractive index of core\n",
      "n2=1.49;    #refractive index of cladding\n",
      "\n",
      "#Calculation\n",
      "thetac=math.asin(n2/n1);       #critical angle in radians\n",
      "thetac=thetac*57.2957795;        #converting radians to degrees\n",
      "theta_c=math.ceil(thetac*10**3)/10**3;   #rounding off to 3 decimals\n",
      "deg=int(thetac);        #converting to degrees\n",
      "t=60*(thetac-deg);   \n",
      "mi=int(t);     #converting to minutes\n",
      "sec=60*(t-mi);    #converting to seconds\n",
      "sec=math.ceil(sec*10**2)/10**2;   #rounding off to 2 decimals\n",
      "\n",
      "#Result\n",
      "print(\"the critical angle of the fibre in degrees is\",theta_c);\n",
      "print(\"critical angle of the fibre is\",deg,\"degrees\",mi,\"minutes\",sec,\"seconds\");"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "('the critical angle of the fibre in degrees is', 68.631)\n",
        "('critical angle of the fibre is', 68, 'degrees', 37, 'minutes', 49.85, 'seconds')\n"
       ]
      }
     ],
     "prompt_number": 10
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example number 3.4, Page number 99"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "#importing modules\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "NA=0.15;     #numerical aperture\n",
      "n2=1.55;    #refractive index of cladding\n",
      "n0=1.33;    #refractive index of water\n",
      "\n",
      "#Calculation\n",
      "n1=math.sqrt((NA**2)+(n2**2));      #refractive index\n",
      "n_1=math.ceil(n1*10**5)/10**5;   #rounding off to 5 decimals\n",
      "alpha=math.asin(math.sqrt(n1**2-n2**2)/n0);     #acceptance angle in radians\n",
      "alpha=alpha*57.2957795;        #converting radians to degrees\n",
      "alphaa=math.ceil(alpha*10**3)/10**3;   #rounding off to 3 decimals\n",
      "deg=int(alpha);        #converting to degrees\n",
      "t=60*(alpha-deg);   \n",
      "mi=int(t);     #converting to minutes\n",
      "sec=60*(t-mi);    #converting to seconds\n",
      "sec=math.ceil(sec*10**2)/10**2;   #rounding off to 2 decimals\n",
      "\n",
      "#Result\n",
      "print(\"refractive index of the core is\",n_1);\n",
      "print(\"the acceptance angle of the fibre in degrees is\",alphaa);\n",
      "print(\"acceptance angle of the fibre is\",deg,\"degrees\",mi,\"minutes\",sec,\"seconds\");\n",
      "\n",
      "#answer for acceptance angle given in the book is wrong"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "('refractive index of the core is', 1.55725)\n",
        "('the acceptance angle of the fibre in degrees is', 6.476)\n",
        "('acceptance angle of the fibre is', 6, 'degrees', 28, 'minutes', 32.55, 'seconds')\n"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example number 3.5, Page number 100"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "#importing modules\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "NA=0.26;     #numerical aperture\n",
      "n1=1.5;    #refractive index of core\n",
      "d=100;     #core diameter in micro meter\n",
      "\n",
      "#Calculation\n",
      "d=100*(10**-6);    #core diameter in metre\n",
      "n2=math.sqrt((n1**2)-(NA**2));\n",
      "n2=math.ceil(n2*10**5)/10**5;   #rounding off to 5 decimals\n",
      "\n",
      "#Result\n",
      "print(\"refractive index of the cladding is\",n2);"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "('refractive index of the cladding is', 1.4773)\n"
       ]
      }
     ],
     "prompt_number": 16
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example number 3.6, Page number 100"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "#importing modules\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "NA=0.26;     #numerical aperture\n",
      "delta=0.015;   #refractive index difference\n",
      "\n",
      "#Calculation\n",
      "#NA=math.sqrt(n1**2-n2**2)\n",
      "#let A=n1**2-n2**2\n",
      "#therefore A=NA**2\n",
      "A=NA**2;\n",
      "#delta=(n1**2-n2**2)/2*(n1**2)\n",
      "#let 2*(n1**2) be B\n",
      "#therefore B=A/delta\n",
      "B=A/delta;\n",
      "n1=math.sqrt(B/2);\n",
      "n1=math.ceil(n1*100)/100;   #rounding off to 2 decimals\n",
      "n2=math.sqrt(n1**2-NA**2);\n",
      "n2=math.ceil(n2*10**3)/10**3;   #rounding off to 4 decimals\n",
      "\n",
      "#Result\n",
      "print(\"refractive index of the core is\",n1);\n",
      "print(\"refractive index of the cladding is\",n2);\n",
      "\n",
      "#answer for refractive index of cladding given in the book is wrong"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "('refractive index of the core is', 1.51)\n",
        "('refractive index of the cladding is', 1.488)\n"
       ]
      }
     ],
     "prompt_number": 19
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [],
     "language": "python",
     "metadata": {},
     "outputs": []
    }
   ],
   "metadata": {}
  }
 ]
}