     public var fieldOfView:Number;
 
     /**
-     *  @copy flash.geom.PerspectiveProjection#focalLength
-     *  
-     *  <p>This property is only used when <code>applyLocalProjection</code>
-     *  is set to <code>true</code>.</p>
-     *
-     *  @see #applyLocalProjection
+     *  The distance between the eye or the viewpoint's origin (0,0,0) 
+     *  and the display object located  in the z axis. During the perspective transformation, 
+     *  the <code>focalLength</code> is calculated dynamically 
+     *  using the angle of the field of view and the stage's aspect ratio (stage width divided by 
+     *  stage height).
+     *  
+     *  <p>This property is only used when <code>applyLocalProjection</code>
+     *  is set to <code>true</code>.</p>
+     *
+     *  @see #applyLocalProjection
+     *  @see flash.geom.PerspectiveProjection
      * 
      *  @langversion 3.0
      *  @playerversion Flash 10

 *    focalLength="no default"
 *    projectionX="0"
 *    projectionY="0"
 *  /&gt;
 *  </pre>
 *

    //----------------------------------
    [Inspectable(category="General")]
    /** 
     *  Used by the subclasses of AnimateTransform to specify
     *  whether the effect changes transform values used by the layout 
     *  manager, or whether it changes values used after layout is run.
     *  Because the Flex layout system ignores 3D transformation properties,
     *  this class overrides the <code>AnimateTransform.applyChangesPostLayout</code> property
     *  to set the default value to <code>true</code> for 3D effects.
     *
     *  @default true
     * 
