| 摘要 |
A scan converter circuit for use in a imaging system that uses a sinusoidally oscillating scanning reflector for scanning an object and a constant rate scanned display monitor for displaying an image of the object. The circuit enables a variable time rate of sampling of picture elements in the object field to match a desired constant display rate of picture elements in the CRT display monitor. The circuit comprises a constant rate VCO clock and a sampling clock that produces periodically variable rate pulses, the periodicity of which being phase locked with zero crossings of the oscillating reflector and wherein the pulses are derived from the constant rate VCO clock. The sampling clock enables an image sensor to sample the radiance levels at a rate which varies with the sinusoidal sweep speed of the oscillating reflector. The circuit further includes a memory circuit for buffering and reversing the order of picture element information during at least one sweep direction, and a transfer control circuit for alternately supplying to the CRT display monitor picture element representations from the sensor and the temporary memory so that picture elements obtained during a right-to-left sweep and a succeeding left-to-right sweep are accurately aligned with each other and bear a one-to-one correspondence with picture elements in the image field.
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