The effect of light from the monitors on the projected image.

Graeme Phillipson, 22nd April 2008

It would be very useful if when an experiment is being performed that someone could remain in the projector side of the laboratory. the reasons for this are so that they can keep an eye on the progression of the experiment and so that they can respond to any questions or requests that the subject has. In order to keep an eye on the experiment and so that the person running the experiment can work on other things while the experiment is running is would be very useful to know that the light produced by the monitors does not significantly effect the contrast between white and black on the projected display. To measure this the photometer was used to recorded the brightness of the screen under different conditions of the monitors being switched on and off.

Condition Brightness (cd/m^2)
Main computer and laptop 0.87
Laptop max brightness 0.21
Laptop min brightness 0.14
All off 0.13

From this we can see that it is quite safe to operate on the projection side without affecting the contrast of the displayed screen.