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The input and outputs are 5V tolerant. Outputs have weak drive above 3.3V but may be
pulled up to 5V with an external 470 Ohm resistor. The trigger input is filtered in the
camera to remove glitches shorter that about 75 nanoseconds, however it is advisable to
provide a 1 microsecond minimum pulse-width for edge-triggered modes and 4
microsecond minimum for the direct exposure mode.
Figure 19, Typical circuit for a switch contact trigger
F
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AMERA
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Each FastCamera is a precise and complex imaging instrument. It undergoes the thorough
outgoing testing with collected sample image data stored on the Test Data CD. This data
collected in a controlled and fully documented procedure can help customers in the
development of a sensor- and application-specific image corrections and enhancements.
The raw test data also serve as the baseline comparison in monitoring image sensor and
camera performance over time.
For the obvious reasons the test procedure and collected data set are somewhat different
for the color and monochrome image sensors. In both cases the test data is stored in the
raw, uncorrected format as the TIFF files. The raw tests data are accompanied by the
corresponding capture camera parameters.
The tests are identical for the FV13 and the FV40 FastCameras with some camera
parameters set at the different values for the high-speed tests.
The tests for the high frame rate uses a special bright LED counter test fixture that is set at
the 100 or 1,000 counts/sec. True camera frame rate is calculated from observations of the
counter transitions in the video sequence. The LED counter transition time and its
brightness are determined by the dwell time limits, its applicability to the measurement of
highest frame rates achievable by the FastCamera.
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6
5
470 Ohms
