3
ISOMET
2,
CONTROL
Two inputs directly control the RF output;
Gate
and
Freq
Modulation
.
The Gate response time (tgm, fig1) is approximately 1msec
The RF Frequency Modulation response time is < 50nsec
The relationship between the driver control inputs, the RF waveform and AO response is shown
below.
Time
FREQ
MODULATION
Input
FREQ
Modulated
RF Output
Zero Order
Max Laser O/P
0 W
Ton
Minimum
(not 0)
Maximum
Maximum
(= Laser O/P)
First Order
Control Range
0 W
Minimum
50MHz "Dummy" FIRST ORDER
ZERO ORDER
RF
tgm
GATE
TTL High
Low
POT Set Level
RF OUTPUT
AOM OUTPUTS (Bragg adjusted for 40MHz)
DRIVER INPUTS
40MHz "Active" FIRST ORDER
40MHz "Active"
50MHz "Dummy"
Figure 1: Typical Digital Modulation Waveforms
