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Three-dimensional display systems
Published in John P. Dakin, Robert G. W. Brown, Handbook of Optoelectronics, 2017
Stereoscopic displays require users to wear a device, such as analysing glasses, that ensures left and right views are seen by the correct eye. Many stereoscopic display designs have been proposed and there are reviews of these in several sources [30,32,34,40,53]. Most of these are mature systems and have become established in several professional markets but suffer from the drawback that the viewer has to wear, or be very close to, some device to separate the left and right eye views. This has limited the widespread appeal of stereoscopic systems as personal displays for home and office use even when the three-dimensional effect is appealing. However, stereoscopic displays are particularly suited to multiple observer applications such as cinema and group presentation where directing individual images to each observer becomes difficult compared to providing each observer with a pair of analysing glasses.
Digital Audio and Video
Published in Skip Pizzi, Graham A. Jones, A Broadcast Engineering Tutorial for Non-Engineers, 2014
So-called passive stereoscopic 3D eyewear uses some sort of filter (different on each eye) to separate the two images presented simultaneously on the screen into a single image for each eye. Early 3D systems used the anaglyph technique (with different colored filters on each eye, used mostly on projection systems in cinemas), wheras more recent passive stereoscopic systems use polarizing filters (with different polarization of light sent to each eye, used in most passive 3D TV systems). Active stereoscopic 3D TV systems use eyewear with electronic “shutters” that allow alternate frames to be seen by each eye (the left eye's shutter is open while the right eye's shutter is closed, and vice-versa). Active 3D eyewear requires a power source (typically a rechargeable battery). In all cases, the type of eyewear must be matched to the screen's method of display, so 3D televisions are typically sold with several sets of the proper eyewear included. 3D televisions may be used for display of regular (“2D”) television content without eyewear. Most 3D televisions also include features for adding “pseudo-3D” imaging to 2D content.
Virtual Environments and Augmented Reality
Published in Terry A. Slocum, Robert B. McMaster, Fritz C. Kessler, Hugh H. Howard, Thematic Cartography and Geovisualization, 2022
Terry A. Slocum, Robert B. McMaster, Fritz C. Kessler, Hugh H. Howard
Traditionally, most personalized displays did not provide enhancements to make the VE appear more realistic (i.e., to look truly 3-D). In recent years, however, it has been increasingly common to present separate images to the left and right eye, thus enabling a stereoscopic view or true 3-D view (Buchroithner et al. 2012), just as we have in the real world (thus providing the stereoscopic depth cue that is shown at the bottom of Table 28.1). Stereoscopy can be accomplished in three ways: passive, active, and autostereoscopic. In a passive display, images for the left and right eye are created simultaneously by the computer/display system, each with a different polarization of light. The user then wears lightweight specialized polarized glasses, which interpret the two images and produce a true 3-D image.3 In an active display, images for the left and right eye are cycled back and forth on the display screen, and the user wears shutter glasses that are in sync with the display screen. In general, passive display systems are less fatiguing on the eye-brain system, but the associated computer hardware is more expensive. With autostereoscopic displays, no specialized glasses are required.4 Although autostereoscopic displays sound ideal, they are more expensive and are typically characterized by a limited number of viewing angles known as “sweet spots.” Presently, autostereoscopic displays are not as commonly used as passive and active ones, but this may change as the technology evolves. Manfred Buchroithner and Claudia Knust (2013) have promoted their use in cartography.
Impact of parallax and interpupillary distance on size judgment performances of virtual objects in stereoscopic displays
Published in Ergonomics, 2019
Bereket Haile Woldegiorgis, Chiuhsiang Joe Lin, Wei-Zhe Liang
Human beings can view 3 D images because the left and right eyes, which are slightly separated, capture two slightly different images. These images are ultimately fused by the brain into one object with additional information, called depth perception or stereoscopy from binocular disparity (Kim 2005; Ukai and Howarth 2008). Depth can also be sensed by accommodation and convergence conflicts of the two eyes (Cutting and Vishton 1995; Kim 2005). Depending on the distance of an object from the eyes of an observer, effective depth judgments can be created from other important cues, such as perspective, object occlusion, shadows, motion parallax and relative size (Cutting and Vishton 1995; Hale and Stanney 2006; Kim 2005). Because the human visual system extracts different information from different cues, all varieties of cues available in the specific environment should be explicitly defined. For example, the depth and shape information obtained from an object fully or partly covered by another (occlusion) is different from height of the visual field (from bottom to top of the visual field). Similarly, the additional information and sometimes contradictions from various cues need to be properly studied. This explained the depth and shape information should not be only based on their independent effect, but also their combination (Landy et al. 1995) as the interaction between them can highlight different issues in accurately understanding the system.
Identification of altitude profiles in 3D geovisualizations: the role of interaction and spatial abilities
Published in International Journal of Digital Earth, 2019
Petr Kubíček, Čeněk Šašinka, Zdeněk Stachoň, Lukáš Herman, Vojtěch Juřík, Tomáš Urbánek, Jiří Chmelík
Based on the number of visual cues used in the visualization, we can distinguish between real and pseudo 3D visualization (Bowman et al. 2005). Pseudo 3D (monoscopic) visualizations use only monocular cues, whereas real 3D (stereoscopic) visualizations include both binocular and monocular depth cues (Buchroithner and Knust 2013). The added value for real 3D visualization is stereoscopy, provided by binocular depth cues (namely binocular disparity). Stereoscopy is ensured by the use of computer graphics and specific peripheral devices for 3D vision such as 3D glasses. Pseudo 3D (monoscopic) visualization is displayed perspective-monoscopically on flat media or on the computer screen (Buchroithner and Knust 2013).
Visual acuity response when using the 3D head-up display in the presence of an accommodation-convergence conflict
Published in Journal of Information Display, 2020
The primary source of the human brain’s depth extraction and 3D perception is the fusion of two images each acquired by only one eye. The amount of horizontal displacement (disparity) for each object appearing in such two images is used in a variety of stereo display technologies to provide depth perception. The first stereoscopic device (stereoscope) was introduced by Charles Wheatstone in 1832. The stereo 3D displays used today range from direct-view stereoscopic displays, which require eyewear, to glassless stereo 3D (autostereoscopic) displays. The eyewear-based stereo displays mainly use one of three different techniques for view separation: (1) color multiplexing; (2) polarization multiplexing; and (3) time multiplexing [11]. A color-multiplexed stereo display separates the two images by color-coding the left and right views, which are then perceived by the viewer wearing the matching-color filter-based glasses. The anaglyph color-coding-based glasses and displays are the best examples of color-multiplexed displays, which were developed in the early twentieth century. In the polarization-multiplexed stereo displays, the polarization directions of light for the stereo views are made mutually perpendicular while the screen is viewed with polarization-matched glasses, which transmit the light (image) intended for a particular eye only. The time-multiplexed displays, on the other hand, use high-refresh-rate displays to display stereo views in the sequence, which are then separated using the active-shutter-based synchronized eyewear. The polarized and active-shutter-glasses-based 3D displays are widely used for the consumer-grade display systems (i.e. 3D TVs and projectors) and in the movie industry (Figure 1).