The above drawings show the basic setup. The fresnel lenses are the
F550 type
from 3Dlens.com. The F550 lens can be used up to 19" (4:3) LCD monitors.
Finding shops that sell large Fresnel lenses is not easy. Sometimes they
are used as screen magnifiers for TV sets. Someone recommended
this shop.
3Dlens.com also sells Fresnel lenses,
and the
F550 type seems most used with LCD's. Update: 3DLens.com no
longer sells the F550 type lenses. I have been told that TV magnifier lenses
also can be used. Google ebay for
these type of products.
This factory in China also sells lenses, up
to 100x100cm,
but I did not have any contact with them.
Finding the right distances for this setup took quite some experimenting:
As you can see from the drawing on the right, each lens magnifies the 17"
monitor screen by a factor that is determined by the lens focal distance and
the distance from lens to monitor. Increasing the lens-monitor distance
increases the magnification factor, but it also increases distortion.
The distances between the 17" monitors will reduce in the magnified image.
It is possible to make a seamless image. But because of the distance between
your eyes, the magnified images will shift. A seamless image will always
mean that one eye sees an image that is partly cut at one side. I did not
like this effect, and therefore I opted for magnified images with a small
black border in between. Also the viewing distance has an influence on the
total image. I had to cut 13mm off the sides of the fresnel lenses to
get optimal view setup.
(cutting fresnel is tricky: The side with the fine grooves scratches easily.
Place it on a soft cloth, and cut the front side with a
plastic/laminate
cutter, making several passes to create a deep score groove)
For the final setup, the magnification factor is 1.44x, this makes the
17" monitors look like 24".
Not bad for this cheap and lightweight setup!
The 75cm viewing distance fits well with the overall distances in the
modular simpit.
For fixing the lenses in front of the monitors, I made a lightweight
wooden frame that can be screwed to the monitor frame. The bottom of the
wooden frame rests on the instrument panel module.
The LCD's are mounted on aluminum plates that are bend in 30 degree angle.
Firm wooden beams give the whole unit sufficient stiffness and strength for
mounting on the simpit.
The
totally five displays are run from a single Atlon 3GHz PC:
One Nvidea GFORCE7800GTX (PCI-e) dual head: one head outputs the 3840x1024
for the Matrox Triplehead2Go splitter, the other head outputs 1024x768 to
the left 15" LCD for the panel.
Then I have another Nvidea GFORCE8400GS (PCI) dual head. One head outputs
the 1024x768 to the other 15" LCD for the right side of the panel. (One head
not used)
The picture left shows the initial test setup. Details on the computer setup
can be found here.
The overall result is not bad: This video gives an impression of the result. The large width (105cm) of the angled scenery display setup gives about 90 degrees view angle. I set the zoom in Flightsimulator at 0.25 via view options menu. The fast moving scenery at the sides provides a good speed cue.
This video gives a detailed explanation of the modular cockpit display system.