Pco dicam C1, Руководство пользователя

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Phosphor decay is a physical parameter of the image
intensifier. After the photocathode is switched off, the
phosphor screen’s light emission decays with a characteristic
time (see Phosphor Activity Curve). This “afterglow” can be
captured by the sCMOS sensor with an additional exposure
time. (=
Phosphor Decay see 8.3 ).
Times Steps
Exposure 4 ns, 10 ns fixed
20 ns ... 250 ns
260 ns ... 1 s
fixed
1 ns
10 ns
Delay 0 ns ... 250 ns
260 ns ... 1 s
1 ns
10 ns
Intrinsic delay < 50 ns
Jitter < 1 ns
Phophor decay 10 µs … 10 ms 1 µs
Phosphor Activity Curve
The phosphor activity curve shows schematically the decay of the
phosphor screen. The various phosphor materials have very different
decay times.
Phosphor Phosphor decay typ. to
…10% …1%
Typical efficiency
P43 1 ms 4 ms 100%
P46 0.2 … 0.4 µs 2 µs 30%
P46:
the extremely short P46 decay process is automatically
integrated into the sCMOS image.
P43:
select a proper phophor decay time of up to 4ms!
sCMOS Sensor
Here the exposure and readout periods of the sCMOS sensor are
shown relative to the action of the image intensifier. The sCMOS
exposure includes the following stages of the image intensifier
scheme:
• Delay time
• Exposure time
•
Phosphor Decay time as described above (see 8.3 )
Example Timing & Frame Rate for P43 vs P46 Phosphor
Type P43 P46
Exposure time 10 µs 10 µs
Configured phosphor decay time 4 ms ≥ 10 µs (minimum)
Readout time for a single image @full
resolution 9.5 ms 9.5 ms
Frame time 13.5 ms 9.5 ms
Resulting frame rate @ full resolution
1
13.5 𝑚𝑚𝑚𝑚 ≈
74 𝑓𝑓𝑓𝑓𝑚𝑚
1
9.5 𝑚𝑚𝑚𝑚 ≈
106 𝑓𝑓𝑓𝑓𝑚𝑚
Note:
selecting a long phosphor decay time for P43 phosphor
reduces the max. frame rate!
NOTICE