Visual display

Field of view and resolution

The projector is usually set to have resolution 800×600 32bit color 60Hz. We can use higher resolutions, but in practice this may reduce the performance of the projector.

with LifeService coil

The projector screen physical dimensions are:

Distance: 50.0 cm
Width: 28.3 cm
Height: 20.0 cm

Converted into degrees of visual angle using 2*atan(14.15/50) and 2*atan(10/50) gives:

Width: 31.6 deg
Height: 22.61 deg

with NOVA coil

The projector screen physical dimensions are:

Distance: 38.5 cm
Width: 25.5 cm
Height: 20.0 cm

Converted into degrees of visual angle using2*atan(12.75/38.5) and 2*atan(10/38.5) gives:

Width: 36.6 deg
Height: 29.1 deg

The projector is set to display to the maximum size of the screen.

In practice, the vertical field of view is most problematic - it depends because different subjects are obstructed more or less due to their particular head geometry and angle with which they place their head. This also depends on which coil is being used. With the new Life Services coil (16 channel receive 4 channel transmit open coil) we can usually see a good deal of the screen, certainly more than half - maybe even the full screen with certain subjects.

So, with these considerations, the usable size should be something like:

Width: 30 deg
Height: 20 deg

With the 4-channel surface coil and the two four-channel blue pads, Topi could get a field of view with the projector of about 10 degrees vertical and 25 degrees horizontal. Perhaps the vertical could be made a bit better - but probably not better than 15 degrees.

The goggles have field of view of 30 x 23 degrees.

Drawing of screen relative to subject

Here is the drawing of relative position of the screen to the subject

Projector JVC DLA-X70 and calibration

Calibrated on 2/17/2012. Basic specification is very similar to the previous model X7. The biggest difference is that it has blue/green edge problem but it isn't very much notable as X7 had red color edge problem. PC:DVI port → DVI-VGA cable → VGA:projector.

Spectrum of RGB KW CMY

Gamma for each color channel measured separately:

Associated xy values:

Gray levels calibration:

Projector Screen

we got it from “Stewart Filmscreen Corporation” and the material is FILMSCREEN 150 SEAMLESS. Thickness is .25“

Eyetracker EyeLink 1000

Sampling rate: 500Hz (It can select 250/500/1000Hz)
Illuminater Power: 100 %

MRI suite floor plans

Subject head will be placed at the center of the magnet and projector screen will be placed about 38.5 cm from the subject eyes.

Here is the drawing for fMRI scanner room

After installation of new console in March 2011, the bay room has been renovated

Schematic drawing of subject space (diameter 38cm for head, 54cm for under the shoulder) in fMRI is below.