Geography Reference
In-Depth Information
Fig. 2 Perception of 3D
objects from planar ''3D
displays'' (from Weiss and
Buchroithner
2012
)
2 Planar Autostereoscopic Displays
2.1 Lenticular Foil Technique
As the term says, planar autostereoscopic displays are flat displays—either ana-
logue, i.e. hardcopies, or digital screens, i.e. softcopies. One of the well known
planar autostereoscopic visualisation techniques is the lenticular foil technique.
This method has been successfully applied to both softcopy and hardcopy displays.
For several years the Dresden company mbm systems Inc., a spin-off of the
Institute for Cartography of the TU Dresden, has successfully been producing
lenticular foil hardcopy displays for operational use in teaching, tourism and ed-
utainment, their major field of production being geodata visualisation.
The lenticular foil technology is an image display method used for the gener-
ation of multi-image effects like 3D visualisations or animations. In order to allow
the spontaneous perception of these effects without any additional viewing aids
(glasses or other means for image separation), lenticular foil displays consist of
two components:
1. the lenticular image, and
2. the lenticular foil.
The transparent lenticular foil serves to separate the individual images that are
seen by the left and right eyes. For this purpose, on its upper side there are a series
of parallel semi-cylindrical micro-lenses (Latin ''lenticulae''). The lower side is
smooth and flat and coincides with the plane of the lenticular image. The latter one
consists of multiple synthetic views (or in the case of ''flat''—i.e. ''no relief''
depictions, e.g. for flipping: partial images) which are cut into small strips and
interlaced in an alternating sequence. Consequently, under each of the semi-
cylindrical lenses one strip of each partial image is situated (Fig.
3
).
The image separation through the lenticular foil occurs according to its optical
properties. The semi-cylindrical lenses focus the parallel incident sight rays onto
