ZHAO Jing, LI Qing-li, XU Li-jun. Simulation research on Bragg reflection bandwidth of cholesteric liquid crystal based on Berreman 4×4 matrix[J]. , 2015,30(5): 777-783
ZHAO Jing, LI Qing-li, XU Li-jun. Simulation research on Bragg reflection bandwidth of cholesteric liquid crystal based on Berreman 4×4 matrix[J]. , 2015,30(5): 777-783 DOI: 10.3788/YJYXS20153005.0777.
Simulation research on Bragg reflection bandwidth of cholesteric liquid crystal based on Berreman 4×4 matrix
This research simulates the reflection spectrum of cholesteric liquid crystal by Berreman 44 matrix and Matlab program
and analyses the factors that affect the bandwidth of reflection spectrum
such as pitch number (thickness of liquid crystal)
refractive index of substrate
birefringence
dispersion of refractive index
fixed pitch
pitch gradient
incident angle and so on. The result illustrates that in order to get an ideal Bragg reflection bandwidth
the thickness of the liquid crystal
the pitch number
N
must reach
N
10; The substrate refractive index can impact the maximum reflection
which will be relatively low when the substrate refractive index
n
g
is smaller than the common light reflection and the affection is more obvious as the
n
g
becomes smaller when
n
g
n
o
a pefect reflection can be attained.The dispersion reflection and big incident angle will make the bandwidth become narrow
while large birefringence
n
and pitch
P
lead to broader bandwidth
but the broadening effects is finite. The reflection bandwidth of the pitch gradient cholesteric liquid crystal was simulated theoretically by giving the function expression of pitch gradient
which makes sense for the experimental study of broadband reflection of cholesteric liquid crystal.
关键词
Keywords
references
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