AGFA 5367/500, Руководство пользователя

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Verifying Acceptable Spatial Resolution, Artifact Levels and
Low Contrast Visibility for mammography application
WARNING:
Good viewing conditions are important for the correct
interpretation of both diagnostic and test images. Make sure
that the light box intensity (luminance) is between 3000 and
6000 cd/m² (4500 and 6500 °K) for mammography. Use a
magnifying glass and use shutters to collimate. Make sure the
ambient light is low.
To verify acceptable spatial resolution, artifact levels and low contrast
visibility, proceed as follows:
1. Print the QC mammography test image or use the previously printed QC
mammography test image used to establish the daily operating density
levels.
2. Visually check the QC test image for artifacts: no significant disturbing
artifacts should be visible.
3. Check the spatial resolution in each of the three circles. Within each circle
there are three groups, each consisting of five dots. All five dots of each
group must be visible with a magnifying glass. The smallest cluster of 5
dots is only visible if the viewing conditions are good.
4. Check the Low Contrast Visibility at both the high (100 / 95%) and low
end (0 / 5%) of the density scale. You should be able to see the circle in
the square and the upper circle.
5. Record these values at the top of Chart 3 (‘Artifacts and Spatial Resolution
Control Chart’).
6. These charts will be used for the weekly quality test.
WARNING:
In case of significant artifacts or insufficient spatial resolution,
the reason must be found and the problem solved before any
further clinical films can be printed.
Related Links
QC test image for mammography application on page 109
Charts for mammography QC on page 144
Performing the weekly QC tests for mammography application on page 117
Preventive maintenance schedule on page 120
Dry 2.4M | Advanced Operation (key-operator mode) | 115
2652B EN 20210601 1655