Electronic Shutter - IAI cm-140ge User Manual

8.3.3 Electronic shutter

CM-140GE/CM-140GE-RA / CB-140GE/CB-140GE-RA /CM-140GE-UV have conventional shutter
functions as well as the GenICam standard "Exposure Time Abs" function.
Preset shutter
10 steps preset shutter are available: OFF (1/31); 1/60, 1/100; 1/250; 1/500; 1/1,000; 1/2,000;
1/4,000; 1/8,000; 1/10,000 sec. (See the register map included in the SDK documentation for
details how to configure this register - 0xA004)
Note: CM-140GE-UV: OFF (1/16); 1/30, 1/60, 1/100; 1/250; 1/500; 1/1,000; 1/2,000; 1/4,000;
1/10,000 sec.
Programmable shutter
It is possible to set the shutter speed in the range of 2L to 1052L by 1L unit, in case of Full Frame
operation. When 1052L is set, it is the equivalent of "OFF (1/31)" or 32.17ms. (See the register
map included in the SDK documentation for details how to configure this register - 0xA008)
30.584µs(1L) * 2 = 61.168µs
Normal
V Binning
The following table is for CM-140GE-UV.
Normal
V Binning
Pulse Width Control
With this mode selected the exposure time is controlled by the width of the trigger pulse. The
minimum trigger pulse width is equal to 1L (30.584µs for GE and 58.9µs for UV)
Exposure Time Abs (GenICam Standard)
This is a function specified in the GenICam standard.
The shutter speed can be entered as an absolute exposure time in microseconds (μs) in register
address 0xA018. The entered absolute time (Time Abs) is then converted to programmable
exposure (PE) value inside the camera.
The below equations show the relationship between the PE value used by the camera for the
different readout modes and the "Exposure Time Abs" value entered in register 0xA018.
As the calculation is based on rounding down to the closest integer, precise values may not always
occur.
The relation between PE value and Time Abs:
Normal readout
clk])
V Binning readout PE= 2 + INT (Exposure time -77) µs / (2524/65000000)
INT means integer (rounded down).
CM-140 GE / -RA/-UV / CB-140GE/-RA
Minimum Shutter Time 2L
38.83µs * 2L = 77.66µs
Minimum Shutter Time 2L
58.9µs(1L) * 2 = 117.8µs
74.79µs * 2L = 149.58µs
PE= 2 + INT (Exposure time -61) µs / (1988 [pixel clocks/line]/65000000[pixel
Maximum Shutter Time
30.5844µs * 1052L≈ 32.174 ms
3232332.Frame(32.17ms)
38.83µs * 527L ≈ 20.46ms
Maximum Shutter Time
58.9µs * 1052L≈ 61.96 ms
3232332.Frame(32.17ms)
74.79µs * 527L ≈ 39.41ms
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