ISOMET RFA1170-4+iMS4-L, Instruction Manual

Page: 9 / 13

9
ISOMET
Schematic of Acousto-optic scanner and drive electronics .
RF
1st Order Scan
0th Order
Input Laser Beam
Intensity Modulation
Tuning Voltage



SEP
SCAN
BRAGG
AO Deflector
Deflector Driver
The input Bragg angle, relative to a normal to the optical surface and in the plane of deflection is:
   
Bragg
=

fc
2.v
The separation angle between the zeroth order and mid scan point of the first order is:

sep
=

fc
v
The first order scan angle is:

scan
=

f
v
Modulation rate (Gaussian profile) is:
Tr = 0.65 d/v
Scanning Resolution is:
N =

f .d/v
where :

= wavelength

f = scan frequency bandwidth
fc = centre frequency
v = acoustic velocity of interaction material
(5.5mm/us for Ge)
d = beam waist along acoustic axis