GE Logiq 500, Расширенное справочное руководство

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Quality Assurance
LOGIQ 500 Advanced Reference Manual
2276614–100 Rev. 0
5–14

Functional resolution
Functional resolution is an imaging system’s ability to detect
and display the size, shape, and depth of an anechoic structure,
as opposed to a pin target. Refer to Figure 5–1 on
5–5 for
details.
The very best possible image is somewhat less important than
reproducibility and stability over time. Routine tests at the same
settings should produce the same results.
The data obtained will give a relative indication of the smallest
structure the system is capable of resolving at a given depth.
To measure functional resolution:
1. Set the front panel TGC slide pots to their center
(detent) position.
2. Gain and acoustic output can be adjusted as
necessary, since these values are displayed on the
monitor.
3. Scan a test phantom with a vertical row of anechoic
cyst targets to typical depths for the probe being used.
4. Evaluate the cysts at various depths for a good (round)
shape, well-defined borders and no fill in. Remember,
TGC slide pots are centered and should remain fixed.
This may NOT provide optimal cystic clearing.
5. Document all results for future reference and
comparison.
Contact a Service Engineer if a greatly distorted image is
obtained.
Description
Benefit
Procedure