© National Instruments
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6-5
NI 17xx User Manual
Maximum Frame Rate
Frame rate is the inverse of the frame period. The frame period is the time from the start of
exposure on one frame to the start of exposure on the next frame, as shown in Figure 6-2.
Figure 6-2.
Frame Period
The frame period is affected by the following factors:
•
Partial scan mode, as described in the
Partial Scan Mode
section of Chapter 5,
Image Sensor
•
Binning, as described in the
Binning
section of Chapter 5,
Image Sensor
•
Exposure time, as described in the
Exposure
section of this chapter
•
Lighting mode, as described in Chapter 4,
Connecting Lighting and External Devices
•
Trigger delay, as described in the
External Trigger
section of this chapter
Determining the Maximum Frame Rate
You can determine the maximum frame rate for your configuration in software by reading the
Max Frame Rate
indicator in Vision Builder AI, reading the
Acquisition Frame Rate Limit
attribute in LabVIEW, or reading the
Max Frame Rate
indicator in MAX.
When external triggering is enabled, do not trigger faster than the maximum frame rate. If a
trigger occurs faster than the maximum frame rate, the trigger is ignored.
Use Equation 6-2 to understand how software determines the maximum frame rate:
(6-2)
where
min frame period
is the minimum amount of time for the strobe and trigger
mode, as described in the
Calculating the Minimum Frame Period
section.
1
Frame Period
Trigger
Expo
su
re
Im
a
ge Re
a
do
u
t
1
max frame rate
1
min frame period
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