Buchroithner, Manfred 
The 2D visualisation technology group contains technologies which only use monocular depth cues. The depth 
perception is based on pure psychological effects, thus the degree of perception is low. A typical example is a 
photograph, a movie or a rendered 3D scene. 
The parallax group (also called pseudo 3D) enfolds visualisation technologies which are based upon 
psychological and physiological effects. Selected binocular and monocular cues are utilised with different 
strength. Parallax visualisations are ranked with a medium degree of perception. Parallar stereoscopic images 
and interlacing technologies belong to this group. 
If all binocular and monocular cues are usable with a visualisation technologie, it is classified to 3D. The degree 
of perception is high, closed to (or like) the natural viewing. Conventional hologrammes or volume displays are 
examples for this group. 
Table 1 shows the proposed group partition and the current state of development. It should be noted, that this 
partition alone does not allow statements about the resulting quality of a spatial image. For example: the use of a 
2D technology with high degree of freedom maybe produce more immersive spatial images than a parallax 
technology with less degrees of freedom. 
Table 1. Division of visualisation technologies for spatial images 
  
  
  
  
  
  
  
  
  
  
d ef group basis depth Cues tech. status 
high 3D psychologic, all of binocular and monocular cues | theoretic or 
physiologic are usable experimental 
medium parallax | psychologic, selected binocular and monocular experimental or 
physiologic cues (with different strength) ready to be used 
low 2D psychologic only monocular cues experimental or 
ready to be used 
  
Compilation: Robert Schenkel 
3D visualisation can devided in stereoscopic and autostereoscopic visualisation (Okoshi 1976; McAllister 1993). 
The difference between them is the need for additional devices (e.g. glasses) to view the spatial image. 
Technologies without additional devices will be referred to as free viewing in the following while the remaining 
will be denoted as aided viewing. The problem of free or aided viewing is considered to be less important for 
the usability of spatial images for cartographic purposes.For example: the wearing of glasses has an influence on 
the degree of immersion, but neither on the degree of perception nor on the degrees of freedom. 
Table 2 renders the result of a review of literature and patents dealing with 3d visualisation devices. Due to of 
the variety of technologies their function will not be explained. For further reading the publications 
(Buchroithner & Schenkel 1999; Okoshi 1976; MacAllister 1993; Hariharan 1996) can be recommended. 
Buchroithner 1999 has described potential 3D visualisation technologies for cartographic purposes. 
Table 2. Technologies for spatial images 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Technology DF DI |DP | Vg | Md | Examples 
S,Sz P,B,O,C HH F S | light emiting volume 
Volumetric | 3 | |sszppoc  |H |H |F| S [rotatinghelixmimor —— 
Imaging E A A denen (eneenn ire enero renee nnn anes 
saad LE LS RR i dile e 
Holography S,Sz,P, B,0,C H.lH F H |hologramme 
dme bn d S8 08.0 (0. ue [RM Fo | Belen stereo nin 
$$ [s prea INIRE S ensem. ai 
2 S 5 S, Sz, B, B, O,C H |M ! F H |lenticular lenses 
ang .e« gl S, Sz, P, B, O, (C) M |M | A | S,H | anaglyphs 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000. 
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