GE Healthcare Brivo XR118, Руководство по обслуживанию

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GE H
EALTHCARE
D
IRECTION
5461425-8EN, R
EVISION
6 B
RIVO
XR118 S
ERVICE
M
ANUAL
Page 138 Section 5.0 - Detector Calibration
Section 5.0
Detector Calibration
5.1 Before You Begin
The following applies when performing Detector (Gain, Bad Pixels) calibrations.
1.) Follow the instructions presented on SUIF.
2.) Correct detector firmware must have been downloaded to the detector before proceeding.
3.) Wireless connection is set up prior to starting this calibration.
4.) There are two steps for calibrating an Image Detector. All two steps must be completed in the
following order: Gain Calibration and Bad Pixel Calibration. Gain calibration must be executed
before Bad pixel calibration is performed.
5.) No flat field phantom is required for the gain calibrations.
5.2 Calibration Overview
Gain Calibration - Tool is used to calibrate a gain coefficient for each pixel in order to achieve
uniform gain across the detector.
Bad Pixel Calibration - Used to detect defective pixels. It can be executed independent of the other
calibrations but is not recommended.
The BAD PIXEL calibration routine:
• Acquires images without using X-rays for the first minutes
• Automatically selects and locks default techniques
• Automatically sets the collimator blades to fully opened size (larger than the detector).
• Displays the Initial Bad Pixel Calibration Screen (Dark Image processing).
5.3 When should it be performed
• During initial system installation.
• Whenever a detector, X-ray tube, Beam quality filtration, Collimator or Ion chamber is
replaced.
• If the Ion chamber is re-calibrated.
• When QAP has failed its isolated defect specification or QAP results have changed by more
than 10% during a two week interval.