AR displays

1-introduction/introduction/introduction.tex

@@ -96,7 +96,7 @@ Between these two extremes lies \MR, which comprises \AR and \VR as different le
 %
 \AR/\VR is most often understood as addressing only the visual sense, and as haptics, it can take many forms as a user interface.
 %
-The most mature devices are \HMDs, which are portable headsets worn directly on the head, providing the user with an immersive \AE/\VE.
+The most promising devices are \AR headset, which are portable displays worn directly on the head, providing the user with an immersive \AE/\VE.
 
 \begin{subfigs}{rv-continuums}{Reality-virtuality (\RV) continuums. }[
         \item Original \RV continuum for the visual sense initially proposed by and adapted from \textcite{milgram1994taxonomy}.

1-introduction/related-work/3-augmented-reality.tex

@@ -62,30 +62,40 @@ Yet, the user experience in \AR is still highly dependent on the display used.
 \end{subfigs}
 
 
-\subsubsection{AR Displays and Perception}
+\subsubsection{AR Displays}
 \label{ar_displays}
 
-\AR systems render virtual content registered in the \RE to the user's senses via output \UIs.
-To create the perception of a combined rea
+To experience a virtual content combined and registered with the \RE, an output \UI that display the \VE to the user is necessary.
+There is a large variety of \AR displays with different methods of combining the real and virtual content (\VST, \OST, or projected), and different locations on the \RE or the user~\cite{billinghurst2015survey}.
 
-\cite{bimber2005spatial}
+In \VST-\AR, the virtual images are superimposed to images of the \RE captured by a camera~\cite{marchand2016pose}, and the combined real-virtual image is displayed on a screen to the user, as illustrated in \figref{itoh2022indistinguishable_vst}, \eg \figref{hartl2013mobile}.
+This augmented view through the camera has the advantage of a complete control on the real-virtual combination such as mutual occlusion between real and virtual objects~\cite{macedo2023occlusion}, coherent lighting and no delay between the real and virtual images~\cite{kruijff2010perceptual}.
+But, due to the camera and the screen, the user's view is degraded with a lower resolution, frame rate, field of view, and an overall visual latency compared to proprioception~\cite{kruijff2010perceptual}.
 
-\paragraph{Spatial Augmented Reality}
+An \OST-\AR directly combines the virtual images with the real world view using a transparent optical system~\cite{itoh2022indistinguishable} to like augmented glasses, as illustrated in \figref{itoh2022indistinguishable_ost}, \eg \figref{watanabe2016transvisible} and \figref{lee2013spacetop}.
+These displays feature a direct, preserved view of the \RE at the cost of more difficult registration (spatial misalignment or temporal latency between the real and virtual content)~\cite{grubert2018survey} and mutual real-virtual occlusion~\cite{macedo2023occlusion}.
 
-\paragraph{Window on World Displays}
+Finally, projection-based \AR overlay the virtual images on the real world using a projector, as illustrated in \figref{roo2017one_2}, \eg \figref{roo2017inner}.
+It doesn't require the user to wear the display, but requires physical surface to project the virtual on, and is vulnerable to shadows created by the user or the real objects~\cite{billinghurst2015survey}.
 
-\paragraph{Video See-Through Headsets}
+\begin{subfigs}{ar_displays}{Simplified operating diagram of \AR display methods. }[
+        \item \VST-\AR \cite{itoh2022indistinguishable}.
+        \item \OST-\AR \cite{itoh2022indistinguishable}.
+        \item Spatial \AR \cite{roo2017one}.
+    ]
+    \subfigsheight{44mm}
+    \subfig{itoh2022indistinguishable_vst}
+    \subfig{itoh2022indistinguishable_ost}
+    \subfig{roo2017one_2}
+\end{subfigs}
 
-Vergence-accommodation conflict.
-
-Using a VST-AR headset have notable consequences, as the "real" view of the environment and the hand is actually a visual stream from a camera, which has a noticeable delay and lower quality (\eg resolution, frame rate, field of view) compared to the direct view of the real environment with OST-AR~\cite{macedo2023occlusion}.
-
-\paragraph{Optical See-Through Headsets}
-
-%Distances are underestimated~\cite{adams2022depth,peillard2019studying}.
-
-% billinghurst2021grand
+Regardless the \AR display, it can be placed at different locations~\cite{bimber2005spatial}, as shown in \figref{roo2017one_1}.
+Spatial \AR is usually projection-based displays placed at fixed location (\figref{roo2017inner}), but it can also be optical or video see-through windows (\figref{lee2013spacetop}).
+Alternatively, \AR displays can be hand-held, like a \VST smartphone (\figref{hartl2013mobile}), or body-attached, like a micro-projector used as a flashlight~\cite{billinghurst2015survey}.
+Finally, \AR displays can be head-worn like \VR headsets or glasses, providing a highly immersive and portable experience.
+%Smartphones, shipped with sensors, computing ressources and algorithms, are the most common \AR today's displays, but research and development promise more immersive and interactive \AR with headset displays~\cite{billinghurst2021grand}.
 
+\fig[0.75]{roo2017one_1}{Locations of \AR displays from eye-worn to spatially projected. Adapted by \textcite{roo2017one} from \textcite{bimber2005spatial}.}
 
 \subsubsection{Presence and Embodiment in AR}
 \label{ar_presence_embodiment}
@@ -173,7 +183,7 @@ The \emph{system control tasks} are changes to the system state through commands
         \item Spatial selection of virtual item of an extended display using a hand-held smartphone~\cite{grubert2015multifi}.
         \item Displaying as an overlay registered on the \RE the route to follow~\cite{grubert2017pervasive}.
         \item Virtual drawing on a tangible object with a hand-held pen~\cite{roo2017onea}.
-        \item Simultaneous Localization and Mapping (SLAM) techniques such as KinectFusion~\cite{newcombe2011kinectfusion} reconstruct the \RE in real time and enables to register the \VE in it.
+        \item Simultaneous Localization and Mapping (SLAM) algorithms such as KinectFusion~\cite{newcombe2011kinectfusion} reconstruct the \RE in real time and enables to register the \VE in it.
     ]
     \subfigsheight{36mm}
     \subfig{grubert2015multifi}

config/acronyms.tex

@@ -48,7 +48,6 @@
 \acronym{DoF}{degree of freedom}
 \acronym{ERM}{eccentric rotating mass}
 \acronym{h}{haptic}
-\acronym{HMD}{head-mounted display}
 \acronym{JND}{just noticeable difference}
 \acronym{LRA}{linear resonant actuator}
 \acronym{MR}{mixed reality}

references.bib

@@ -1256,6 +1256,17 @@
   doi = {10/gf39qd}
 }
 
+@article{grubert2018survey,
+  title = {A {{Survey}} of {{Calibration Methods}} for {{Optical See-Through Head-Mounted Displays}}},
+  author = {Grubert, Jens and Itoh, Yuta and Moser, Kenneth and Swan, J. Edward},
+  date = {2018},
+  journaltitle = {IEEE Trans. Vis. Comput. Graph.},
+  volume = {24},
+  number = {9},
+  pages = {2649--2662},
+  doi = {10/gd3k7g}
+}
+
 @incollection{gueorguiev2022larger,
   title = {Larger {{Skin-Surface Contact Through}} a {{Fingertip Wearable Improves Roughness Perception}}},
   booktitle = {Haptics: {{Science}}, {{Technology}}, {{Applications}}},
@@ -1562,6 +1573,17 @@
   doi = {10/gr2fbm}
 }
 
+@article{itoh2022indistinguishable,
+  title = {Towards {{Indistinguishable Augmented Reality}}: {{A Survey}} on {{Optical See-through Head-mounted Displays}}},
+  author = {Itoh, Yuta and Langlotz, Tobias and Sutton, Jonathan and Plopski, Alexander},
+  date = {2022},
+  journaltitle = {ACM Comput. Surv.},
+  volume = {54},
+  number = {6},
+  pages = {1--36},
+  doi = {10/gmk7c8}
+}
+
 @inproceedings{jacob2008realitybased,
   title = {Reality-Based Interaction: A Framework for Post-{{WIMP}} Interfaces},
   shorttitle = {Reality-Based Interaction},
@@ -1922,6 +1944,15 @@
   doi = {10/ggfv5d}
 }
 
+@inproceedings{kruijff2010perceptual,
+  title = {Perceptual Issues in Augmented Reality Revisited},
+  booktitle = {{{IEEE Int}}. {{Symp}}. {{Mix}}. {{Augment}}. {{Real}}.},
+  author = {Kruijff, Ernst and Swan, J. Edward and Feiner, Steven},
+  date = {2010},
+  pages = {3--12},
+  doi = {10/fr6gz3}
+}
+
 @article{kuchenbecker2006improving,
   title = {Improving Contact Realism through Event-Based Haptic Feedback},
   author = {Kuchenbecker, K.J. and Fiene, J. and Niemeyer, G.},
@@ -2806,6 +2837,12 @@
   doi = {10/ggrd6q}
 }
 
+@thesis{roo2017one,
+  title = {One Reality: Augmenting the Human Experience through the Combination of Physical and Digital Worlds},
+  author = {Roo, Joan Sol},
+  date = {2017}
+}
+
 @inproceedings{roo2017onea,
   title = {One {{Reality}}: {{Augmenting How}} the {{Physical World}} Is {{Experienced}} by Combining {{Multiple Mixed Reality Modalities}}},
   shorttitle = {One {{Reality}}},