Geography Reference
In-Depth Information
Fig. 3
Principle of the lenticular foil technique (from Gruendemann
2004a
, p 15)
particular strips of the lenticular image. If the viewer changes his/her perspective
by turning or tilting the lenticular foil display perpendicular to the lenses, the
vision rays are focused onto other strips of the display. This enables the perception
of the spatially separated image information out of one lenticular image, because
from a particular viewing angle the viewer only sees one strip per semi-cylindrical
micro-lens. More comprehensive information about the lenticular foil technology
can be found in Okoshi (
1976
), Gruendemann (
2004a
,
b
), Buchroithner et al.
(
2004a
,
2005a
,
b
,
c
), as well as Gruendemann et al. (
2006
).
A significant strong point of the lenticular foil technology is its versatility
concerning displayable effects. They can be divided into two categories: 2D- and
3D effects. Each of these major categories contains special effects (true-3D, flip,
morphing, zoom, and animation). Besides 2D- or 3D effects lenticular foil displays
also can visualise a combination of 2D- and true-3D effects.
Displays with 2D effect typically have micro-lenses running in a horizontal
direction. Thereby a supply of the same image information to both of the viewer's
eyes is achieved. Horizontal tilting of the lenticular foil display then changes the
image content. For lenticular foil displays with true-3D effect, however,
the semicylindrical lenses must be aligned vertically. This configuration results in
the visual perception of different images of the same object(s) by the two eyes.
In either case, the displays can be generated as reflectance displays (incident light/
''looking at'') or transmission displays (transmitting light/''looking through'').
Due to the various 2D- and 3D effects the lenticular foil technique offers
versatile possibilities for cartographic visualisation. The 3D-effect is only used to
visualise relief. For example, the lettering can also be displayed virtually hovering
