An acousto-optic, Bragg-deflection-type RF spectrum analyzer is made in a planar waveguide in LiNbO3 with an index n = 2.0. Signals with modulation frequencies ranging from 50 to 500 MHz are analized...

An acousto-optic, Bragg-deflection-type RF spectrum analyzer is made in a

planar waveguide in LiNbO3 with an index n = 2.0. Signals with modulation

frequencies ranging from 50 to 500 MHz are analized by using them to drive

the acousto-optic transducer which produces a traveling acoustic wave in the

LiNbO3 with a velocity υa = 3000 m/s. The optical beam has a wavelength

in air of λ0 = 6328 A and a width ˚ b = 1 mm. The interaction length =

5 mm.

(a) What is the angular deflection (in degrees) when the modulation frequency is 500 MHz?

(b) What is the number of resolvable spots (the ratio of the envelope width

to the spot width) at a frequency of 500 MHz?