CM-140GE / -RA/-UV / CB-140GE / -RA
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The following table is for CM-140GE-UV.
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 PE= 2 + INT (Exposure time -61) µs / (1988 [pixel clocks/line]/65000000[pixel
clk])
V Binning readout PE= 2 + INT (Exposure time -77) µs / (2524/65000000)
INT means integer (rounded down).
The below table shows minimum and maximum values for each readout mode.
CM/CB-140GE
Minimum value
Maximum Value
Normal Scan
61
µ
s
32,174
µ
s
2/3 Partial Scan
61
µ
s
25,019
µ
s
1/2 Partial Scan
61
µ
s
21,471
µ
s
1/4 Partial Scan
61
µ
s
16,149
µ
s
1/8 Partial Scan
61
µ
s
13,519
µ
s
V-Binning Scan
77
µ
s
20,464
µ
s
CM-140GE-UV
Minimum value
Maximum Value
Normal Scan
117.8us
61,967 us
2/3 Partial Scan
117.8us
48,184 us
1/2 Partial Scan
117.8us
41,351 us
1/4 Partial Scan
117.8us
31,102 us
1/8 Partial Scan
117.8us
26,036 us
V-Binning Scan
149.58us
39,413 us
GPIO in combination with Pulse Width trigger
More precise exposure time can be obtained by using the GPIO in combination with Pulse Width
trigger mode. The clock generator and counter can be programmed in very fine increments. As for
the setting example, refer to chapter 6.5.1.
Minimum Shutter Time 2L
Maximum Shutter Time
Normal
58.9µs(1L) * 2 = 117.8µs
58.9µs * 1052L≈ 1 Frame (61.96 ms)
V Binning
74.79µs * 2L = 149.58µs
74.79µs * 527L ≈ 39.41ms