1.1: INSTRUMENT PARTS
(Click on images to view full size)
From Figure 1:
1. Signal Tower – Indicates status of the X-ray system. Green means power on, yellow means the door is closed properly, and red means X-ray is on.
2. Interior Camera Display – To view inside the machine when the cabinet is shut and the X-ray is ON.
3. PC interface – For all controls, i.e. activations of x-ray source, movement of components, etc.
From Figure 2:
4. X-ray Source
5. Objectives – There are five objectives of optical magnification; four fine objectives (2x, 4x, 10x, 20x) on the left of the detector and a 0.5x on the right.
6. Detector (CCD)
7. Sample Stage – Sample to be secured on here (Details in Section 1.3).
NOTE: Axis orientation marked in Figure 2 (X-axis coming perpendicularly out of page).
1.2: POWERING UP THE SYSTEM
The scanner will not usually be turned off and the system will be on when you come in. Press the Emergency Off (EMO) button (Figure 3) only in case of emergency. The PC will be on and there is no account to login. If there is a problem in powering up (or resetting) the system, check that the EMO button is pulled out.
If the problem continues, check the breaker box (Figure 4) located near the base of the scanner, flip all switches up and switch the main breaker on Figure 5. If there has been a power surge then this will need to be flipped to the ON position.
1.3: PREPARING YOUR SAMPLE
The sample will be fitted in a sample holder and then placed on a platform within the scanner (Figure 6). There are multiple sample holders for different types of samples. You may find them in a cabinet directly to the right of the micro CT system.
Your sample needs to be stable. During acquisition, the sample is rotated. There should not be morphological change of the sample or there is risk of image distortion,such as ring artifacts. Biological samples are prone to this (e.g. an organ or limb shifting due to gravity. Use wax, foam, or padding to immobilize it.
Another type of image distortion that can occur is beam hardening. This can occur if the sample contains or is near metal. This occurs since the metal is too dense and reflects the beams.