Frame Rate - Photon Focus MV3-D640I-M01-144-G2-12 User Manual

Frame Rate

8.1 Introduction
The maximal frame rate of the camera depends on the camera settings. The following factors
influence the maximal frame rate (see also Table 8.2):
• The read-out mode configuration: Sequential [non overlapping] or Interleave
[overlapping]) (Section 8.2).
• The length of the exposure time: A shorter exposure time can lead to an increase in the
maximal frame rate.
• ROI height: a smaller ROI height can lead to an increase in the maximal frame rate.
• ROI width: a smaller ROI width can lead to an increase in the maximal frame rate.
• PixelFormat: the maximal frame rate might be smaller than the maximal sensor frame rate
because otherwise the maximal data rate at the interface (MaxDataRateInterface) would be
exceeded. The maximal sensor frame rate can be achieved at the default settings of
PixelFormat=Mono8 and MaxDataRateInterface=896 MBit/sec.
The maximal frame rate of the camera can be determined by a frame rate calculator in the
support section of the Photonfocus web page www.photonfocus.com. The maximal frame rate
with the current camera settings can be read out by a camera register
(AcquisitionFrameRateMax). A table with values for common ROI settings is shown in Section 8.8.
8.2 Read-out Mode
The MV3-D640I CMOS cameras provide two different readout modes:
Sequential (non overlapping) Read-out [Interleave = False]: Exposure time of the next image
can only start if the readout time of the current image is finished. Frame time is the sum
of exposure time and readout time.
Interleave (overlapping) Read-out [Interleave = True]: Exposure time of the next image can
start during the readout time of the current image. The frame time is determined by the
maximum of the exposure time or of the readout time, which ever of both is the longer
one.
In interleave read-out mode the following two situations need to be distinguished in order to
calculate the maximal allowed frame rate:
Interleave Read-out Timing 1: Exposure Time <= Read Out Time + TIntSampling (see Section
8.5).
Interleave Read-out Timing 2: Exposure Time > Read Out Time + TIntSampling (see Section 8.6).
A formula for the calculation of the maximal frame rate is given in the next sections.
MAN076 09/2017 V1.0
8
51 of 121