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Image projection and object resolution

Normally the vertical pixel pitch is equal to the horizontal pixel pitch: $LS_{pitch} = P_{pitchv}$. The achievable vertical and horizontal object resolution are dependent from depth positions of objects to be represented by the screen - according to the fan projection, shown in fig.2:
\begin{displaymath}

\Delta X_{obj}=\Delta Y_{obj}=\frac{\left( Z_{obj}-Z_{obs}\right)

LS_{pitch}}{Z_{screen}-Z_{obs}}

\end{displaymath} (5)

The possible depth resolution of the objects depends in addition from the $\Delta$horizontal distance of the viewing centers, say distance of the two watching eyes: $D_{eye}$. The smallest sampling angle might be denoted by $\Delta\beta$: It is slightly dependent on the angle $\beta$ itself because $\Delta X_{obs}$ is constant.

\begin{displaymath}

\Delta \beta =\frac{\Delta X_{obs}\cdot \left[ \cos \left( \beta \right)

\right] ^{2}}{Z_{screen}-Z_{obs}}

\end{displaymath} (6)

Let k be the number of views between the eyes. Then the eye distance corresponds to the sampling angles as follows:
\begin{displaymath}

D_{eye}=k\cdot \Delta X_{obs}

\end{displaymath} (7)

where a symmetrical eye position is assumed.

With respect to the two projections centers the following depth sampling planes $Z_{sp}\left( k,i\right)$ for objects are given:

\begin{displaymath}

\left[ Z_{obs}\left( i,k\right) -Z_{screen}\right] =\frac{i\...

...dot \left[ Z_{obj}\left( i,k\right) -Z_{obs}\right]}

{D_{eye}}

\end{displaymath} (8)

Let be the sampling distances on the screen $\Delta X_{screen} = LS_{pitch}$ and those at the eye plane of the observer $\Delta X_{obs}$. Then % latex2html id marker 524

$\left(

\ref{Eq_Zobs1} \right)$ results into the following equation:
\begin{displaymath}

Z_{obj}\left( i,k\right) =\frac{Z_{screen}\cdot k\Delta X_{o...

...

\cdot i\Delta X_{screen}}{k\Delta X_{obs}-i\Delta X_{screen}}

\end{displaymath} (9)




Next: Sampling distances Up: 3dprojtn Previous: Brief description of the

2000-08-21