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This paper describes application of versatile one-dimensional high-speed video
camera system to motion analysis. This system consists of linear-image sensor, frame
memory and personal computer. This linear-image sensor scans object image onedimensionally
at the rate of 2 MHz(maximum), and outputs analog signal to the
interface between this sensor and the frame memory.The interface then adds
horizontal and vertical synchronization signals to simulate NTSC-like composite video
signal at the lower sampling rate for frame memory. This frame memory has
resolutions of 5 1 2(H)X5 1 2(V)X25 6(I) and reconstructs 5 1 2 dots' intensity distribution
into a line, then 480 line images become a full two-dimensional image on framememory.
At the maximum speed, sampling clock is 2.048 MHz, so shortest sampling
period between line-scannings is 250 micro seconds. This is not so high speed
compared with traditional streak cameras. But resultant images can be digitized and
stored in the memory. Therefore various image-analysis and motion analysis can be
performed with personal computer.
Experiments were performed to test this video-recording camera. The object was
movement of Z-axis linear stage driven by stepping motor (1 micro meter/pulse),
which is totally controlled by host computer. The video-camera was operated at 512
KHz to 2.048 MHz. The resultant trajectory stored on frame-memory was timedisplacement
characteristic of object. Because no moving part is included in this
camera, synchronization between camera and object can be done in microseconds
precision. And recording speed of the camera system can be switched in every horizontal
scan. So object's displacement in one scan can be adjusted to be about pixel separation
of the image sensor, therefore quantum error due to spatial digitization can be
SPIE Vol. 1358 19th International Congress on High-Speed Photography and Photon/cs (1990) / 351
minimized. In addition experimental results can be observed and analyzed immediately
after recording.
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