Pyrocam IV Oper
ator’s Manual
Document No. 50337-001
Rev F
2/21/2017
Page 17
∆𝑇 = 𝐿𝑎𝑠𝑒𝑟 𝑝𝑢𝑙𝑠𝑒 𝑝𝑒𝑟𝑖𝑜𝑑
𝑇
𝑟
= 𝑟𝑒𝑠𝑝𝑜𝑛𝑠𝑒 𝑑𝑒𝑙𝑎𝑦
(All times are in µsec unless noted otherwise)
3.3.3
Mode 1, Single-Shot Operation
Mode 1 describes operation when the laser fires at a trigger rate of <3Hz, including non-
repetitive or Single-Shot triggers.
diagrams the trigger timing requirements
for this mode of operation. In this mode, the laser must fire within an exposure time
window that begins 10µs after the rising edge of the applied trigger. The entire laser
pulse duration must be contained within the programmed
Exposure
time. In general,
you should program the
Exposure
time to extend 10-15% longer than the actual laser
pulse width.
To remain in mode 1, you must restrict your trigger rates to be <3Hz. The Pyrocam
automatically switches from Mode 1 to Mode 2 if the trigger rate meets or exceeds 3Hz.
Figure 3.1 : Mode 1, Single Shot,
𝒇
𝒕𝒓𝒊𝒈
< 𝟑𝑯𝒛
𝑇
𝐸
= 𝑇
𝑙𝑤
+ 20
for
𝑇
𝑙𝑤
< 100
𝑇
𝐸
= 1.15 𝑇
𝑙𝑤
for
𝑇
𝑙𝑤
≥ 100
3.3.4
Mode 2, Periodic Operation
In Mode 2 trigger pulses must arrive at a periodic rate. Refer to
. The
Exposure
time should be set to contain just the pulsed event to be captured. If the
exposure time is set too long (after the pulse) it will result in a loss of signal due to array
cooling before detector readout.
If the trigger source is unstable or turns on and off, some loss of uniformity shot to shot
will likely result. For best operation, calibrate the Pyrocam at the trigger rate being used
and recalibrate if the rate changes.
