# Chapter 11 : Integrated optics and photonics¶

## Example 11.1, page 624¶

In :
import math

#Variable declaration
h=1.3*10**-6                            #wavlength
d=25*10**-6                             #distance between the electrodes
n1=2.1                                  #refractive index
r=30.8*10**-12                          #electro-optic coefficient
l=2*10**-2                              #length

#Calculation
V=(h*d)/(n1**3*r*l)                       #voltage

#Result
print'Voltage = %.1f V'%V

Voltage = 5.7 V


## Example 11.2, page 629¶

In :
import math

#Variable declaration
n1=3.1                                         #refractive index
thet=1                                      #angle in degree
h=1.52*10**-6                                  #wavelength
l=10**-2                                         #length

#Calculation
ne=n1*math.sin(2*thet*math.pi/180)             #effective refractive index
D=h/(2*ne)                                     #Corrugation period
s=D*h/l                                        #filter bandwidth

#Result
print'Corrugation period = %.1f um'%(D*10**6)
print'Filter 3 dB bandwidth = %.1f Å '%(s*10**10)

Corrugation period = 7.0 um
Filter 3 dB bandwidth = 10.7 Å


## Example 11.3, page 631¶

In :
import math

#Variable declaration
n1=8                                #no of bands
N1=0                                #no of channels between any two bands
N2=1                                #no of channels between any two bands
N3=2                                #no of channels between any two bands
M=4                                 #no of channels in each band

#Calculation
Cs1=(n1-1)*N1                       #total number of channels skipped
Ct1=(n1*M)+Cs1                      #total number of channels for 4 skip-0 scheme
Cs2=(n1-1)*N2                       #total number of channels skipped
Ct2=(n1*M)+Cs2                      #total number of channels for 4 skip-1 scheme
Cs3=(n1-1)*N3                       #total number of channels skipped
Ct3=(n1*M)+Cs3                      #total number of channels for 4 skip-2 scheme

#Result
print'Total number ofchannels required for each interleaver band filter'
print'(i) 4-skip-0:'
print'     Ctotal = %d'%Ct1
print'(ii) 4-skip-1:'
print'     Ctotal = %d'%Ct2
print'(iii) 4-skip-2:'
print'     Ctotal = %d'%Ct3

Total number ofchannels required for each interleaver band filter
(i) 4-skip-0:
Ctotal = 32
(ii) 4-skip-1:
Ctotal = 39
(iii) 4-skip-2:
Ctotal = 46