# Chapter 17: Introduction To Fiber Optic Technology¶

## Example 17.1, page no. 557¶

In [4]:
# Variable Declaration
n1       = 1.50              # Refractive Index of Substance 1
n2       = 1.46              # Refractive Index of Substance 2

# Calculation
import math     # Math Library
THEETA_c = math.asin(n2/n1)  # Critical angle of incidence (degrees)

# Result
print "The critical angle of incidence between two given substances is THEETA_c =",round(THEETA_c*180/math.pi,1),"degrees."

The critical angle of incidence between two given substances is THEETA_c = 76.7 degrees.


## Example 17.2, page no. 566¶

In [7]:
# Variable Declaration
tr  = 2.00*pow(10,-9)      # Rise Time (s)
Cd  = 3.00*pow(10,-12)     # Capacitance (F)
Cdh = 2.00*pow(10,-12)     # Assumed Capacitance (F)

# Calculation
import math   # Math Library
BW  = 0.35/tr              # Bandwidth (Hz)
Rl  = 1/(2*math.pi*BW*Cdh) # Resistance (Ohms)

# Result
print "BW =",round(BW/pow(10,6)),"MHz"
print "Rl =",round(Rl),"Ohms"
print "In practice, a value approximately 25 percent of this calculated value will be used."

BW = 175.0 MHz
Rl = 455.0 Ohms
In practice, a value approximately 25 percent of this calculated value will be used.


### Example 17.3, page no. 569¶

In [12]:
# Variable Declaration
Mu_A = 40.00               # Diode Current (uW)
Mu_W = 80.00               # Incident Light (uW)

# Calculation
import math   # Math Library
R    = Mu_A/Mu_W   # Responsivity (A/W)

# Result
print "The Responsivity of the light detector is R =",round(R,1),"A/W."

The Responsivity of the light detector is R = 0.5 A/W.