Cambridge Research Systems BOLDScreen
The Cambridge Research Systems BoldScreen an MRI-safe 24" LCD display located at the head end of the magnet bore. Participants are able to view this display though a mirror mounted on top of any of our head coils. A second identical BOLDScreen is associated with the Mock Scanner on the fourth floor.
Safety
"DO NOT UNDER ANY CIRCUMSTANCES TAKE STANDARD ALLEN KEYS INTO THE MAGNET ROOM. DO NOT SUBSTITUTE STEEL MOUNTING SCREWS FOR THE NON-MAGNETIC STAINLESS SCREWS."
Monitor
The BOLDScreen monitor is MR Safe. It does not pose a hazard in the scanner room.
Eddy-currents make the monitor difficult to move near the magnet. There is considerable magnetic resistance to any movement in high field areas. Move the monitor slowly until it has cleared the main magnetic field.
We strongly suggest any adjustments or removing the monitor from the trolly be done outside the scanner room. Any adjustment to the clamp screws must be made using the purple titanium allen key ONLY. The purple key is kept in the tool drawer in the scanner suit. Always replace the key in the tool drawer after using it. Adjusting the hight or removing the monitor from the trolley is a two person job. Do not attempt it by yourself. Ask for help!
Trolley
The non-magnetic BOLDScreen Trolley is MR Safe.
The trolley with attached monitor weighs 61.5kg. Use care when moving it especially near the magnet or over any uneven surfaces. Be aware the assembly is somewhat top heavy and would be difficult to control if it started to tip over. Get help if you need to move the trolley outside of the scanner room.
Power Supply
The Power Supply is MRI Conditional. It is safe within the 3.0T magnet room but must be kept near the wall and away from high field areas.
DO NOT MOVE THE POWER SUPPY.
If you need to move the power supply ask Andrew or Paul for assistance.
Cables
The BOLDScreen cables are MRI Conditional. They are safe as long as they are attached to the BOLDScreen and the screws are tightened. The connectors are ferromagnetic and will move when not securely attached to the monitor. When the cables are not attached, they should be stowed along the wall or removed from the room.
RF BURN HAZARD: NEVER ROUTE THE BOLD SCREEN CABLES OVER THE PARTICIPANT OR THROUGH THE SCANNER BORE.
Operation
Switching On / Off
Switch the bold screen on at the wall outlet inside the MRI room. The wall outlet is located behind the wood storage cabinet near the entrance door. The Bold screen should power on and display either the internal self-test or whatever is on the stimulus PC.
If the Bold Screen does not power on, check the on / off switch on the back of the power supply. The power supply is on the floor to the left of the wood storage cabinet.
When you are done with the Bold Screen, switch it off at the wall outlet.
Status LED
The status LED is on the side of the BOLDScreen just above the power socket. It will be blue during normal operation. If it is not lit up, check the power connections and switches.
PC Settings
The stimulus PC should be set to 1920x1200, 24-bit, 60Hz. The Bold Screen does not have a rescaler and will only work at this single resolution. Leaving out the rescaler avoids a one frame latency. If you are also running the same stimulus program outside the scanner be aware that most standard computer displays do have a rescaler and may have the one-frame latency.
Moving the Bold Screen
If you need to move the Bold Screen away from the magnet bore, ask Andrew or Paul for assistance. The attached cables are ferromagnetic. One of us should show you how to remove and stow the cables safely.
Specifications
Screen Size: 24" diagonal. The active area of the screen is 518.4mm x 324.0mm with .270mm pixel pitch
Resolution: 1920x1200
Input: 1920x1200, 24 bit, DVI, 60Hz.
Grey-to-Grey Response Time: 5mS typical
Backlight switching frequency: 74.1kHz
Backlight trigger: Opto isolated TTL Input 0 to 5Vdc
Automatic compensation of brightness for temperature and ageing using a built-in sensor. The built in luminance sensor masks off the top left 16x16 pixels.
Maximum Brightness: 1000cd m2. The factory default setting is 800cd m2 We turned it down from the default as 800 was still too bright. To adjust this. See the next section.
RF emissions: The user manual claims no effect observed on functional and structural MRI scan when the monitor is located at the exit of the bore. This is not strictly true. When running diagnostic scans we found a small observable artefact when the bold screen is powered on and directly adjacent to the the exit of the bore. Moving the screen back an inch greatly reduces the artefact.
Monitor Weight: 16.5kg
Weight with attached trolly: 61.5kg (136lb.)
Adjustments
Height
Do not attempt to adjust the display hight by yourself. You must have a second person helping.
Strong eddy currents make the display difficult to move when near the magnet bore. Before adjusting the height, slowly roll the trolly back away from the magnet bore until it is clear of the main magnetic field.
To adjust the height, first loosen the two hand wheels locking the monitor onto the trolley. Once it loose you and a helper can lift the monitor out of the slot in the trolley column and put it back at a different height. Tighten the two hand wheels.
Brightness and Mirror Mode
The Bold Screen does not have conventional controls for adjusting settings like brightness. Instead these settings are contained on a removable SD card. There is also a USB interface that can only be used if the BoldScreen is outside of the magnet room. In practice it is far easier to move the SD card than the entire Bold Screen.
Make a backup of the SD card before making any changes.
To make changes, mount the SD card on a PC and navigate to the firmware subdirectory. Look for the file BOLDScreen_CFG.xml. This file can be edited with any plain text editor like Notepad on Windows. On a Mac you can use TextEdit or Smultron.
To adjust the brightness, edit this line:
<Entry Candela="800" />
Replace the number in quotes with the desired luminance in cd m-2. The default value is 800 and the maximum is 1000. We've turned it down from the default as 800 was too bright.
Participants normally view the Bold Screen through a mirror, so left right mirroring is turned on. To turn off mirroring edit this line:
<Entry MIRROR_MODE="1"/>
Change the 1 to a 0 to turn off mirroring.
All of the other settings should be left alone. If you are curious the are described in the Operator's Manual.
Backlight Trigger
There is one but it isn't connected. If you need to use the backlight trigger, we would need to purchase an isolator.