> We could also put in an image of the SV-3 display being worn to go
> with Figure 1 if people think it would add something
I think that'd be a good idea.
I think the article is good as I understood all of it just fine, and I
don't know much about this.
On Sat, 2003-01-18 at 10:43, Thad E. Starner wrote:
>
> Here is a draft of a short article I'm preparing for IEEE Pervasive
> Computing magazine. I would appreciate suggestions on how to improve
> it as it is intended for a technical audience who does not necessarily
> know about wearable displays.
>
> The image for Figure 1 is at
> http://www.cc.gatech.edu/~thad/overlay-sv3.jpg
>
> and the caption I'm suggesting is
>
> Figure 1: Simulation of the overlay effect of using a monocular
> opaque head-up display.
>
> I was thinking of putting in a figure that helps illustrate the power
> difference between PDAs and HUDs, but I think the analogy works well
> enough and my drawing skills are poor. Opinions?
>
> We could also put in an image of the SV-3 display being worn to go
> with Figure 1 if people think it would add something.
>
> Thad
>
> ------------
> The Enigmatic Display
>
> The monocular head-up display is the most distinctive component
> of many wearable computers. Yet this style of display is often
> misunderstood as to how and why it is used. This month I examine the
> most common questions on wearable displays and point to new
> research on their use.
>
> *Why use a head-worn display?*
>
> In many industries, workers have both hands occupied while requiring
> access to information. For example, a surgeon may perform an
> intricate microscopic procedure while watching a magnified view of his
> actions on a head-up display. An overlay of the patient's vital signs may
> provide the surgeon additional context during the procedure.
> Similarly, a network technician might use a head-up display so that he
> can monitor packet transmission while using his hands to physically
> reconfigure a router. In Europe, BMW recently showed an augmented
> reality (AR) system for automobile technicians; the head-up display was
> used to overlay 3D graphics on a BMW engine which guide the technician
> for each required step in the engine's service.
>
> Beyond industry, monocular head-up displays also show potential in
> consumer products. A growing number of individuals have adopted these
> displays as part of their normal life. For me, the display provides a
> quick way to access my calendar, refer to notes while teaching class,
> inconspicuously write notes on a conversation, or even read the next
> paragraph of an article while walking to my next appointment. I have
> even been known to use a head-up display to read in bed so as to avoid
> the fatigue of holding a book over my head for extended periods of
> time.
>
> *What does the display look like? What can you do with it?*
>
> Figure 1 shows a simulation of using the MicroOptical SV-3 monocular
> display. The SV-3 is a color VGA display with 640x480
> resolution and a 16 degree horizontal field of view (19 degree
> diagonal). In practice, the image from the computer seems to float in
> space, overlaid on the real world. Because of a trick of the human
> visual system, most users perceive that they "see through" the display
> even though it is opaque.
>
> A similar effect can be seen by holding your thumb a couple of inches
> in front of one eye while focusing on something in the distance with
> the other. The thumb is out of focus, of course, but you perceive
> both your thumb and the object in the distance, even if the object
> would at first seem to be obscured by your thumb. Closing first one
> eye and then the other demonstrates how different the images to each
> eye really are. Opaque head-up displays take advantage of this effect
> to create the illusion of overlay. In addition, they use optics (much
> like those of a microscope) so that both the display and the distant
> object are in focus simultaneously.
>
> Since many of these units can be driven from a standard VGA port, they
> are capable of displaying information just like a normal desktop
> computer. In general, monocular displays can be used by anyone with
> normal vision, corrected or uncorrected. Some displays clip on to
> eyeglasses or sunglasses if the user does not wear eyeglasses.
> Other displays are mounted to a form of headband and sit forward far
> enough from the forehead that the user can wear eyeglasses underneath.
>
> --------------------------------------------------
> TABLE/SIDEBAR
> Advantages of head-worn displays:
>
> Size/weight
> Speed of access
> Less vulnerability to damage
> Hand support unnecessary
> Less strain/fatigue for back, neck, and hands
> Adjustable focus
> Less power
> Virtual overlay on physical world
> Privacy
> Less interruptive
> Potential for large virtual image
> --------------------------------------------------
>
> *What are the advantages of a head-worn display?*
>
> Compared to the displays of a laptop or PDA, modern head-worn
> monocular displays have a distinct size and weight advantage. For
> example, the head of my display weighs 35 grams (slightly over an
> ounce). When I am not wearing my display, I store it in my shirt
> pocket. In today's world, most people assume that it is an earphone
> for a cellular phone or a MP3 player. However, when I need it, I can
> still access the display very quickly.
>
> This speed of access is another significant advantage. PDA users must
> reach into their pocket or briefcase, uncase the PDA, boot it, pull
> out the stylus, and get to the right application. With a head-up
> display and a fast mounting system, the user can access their system
> in as little as 1/10 of the time of a PDA user. Such accessibility
> allows frequent use of the display and wearable computer for quick
> reference and note-taking.
>
> Since a head worn display is small and mounted near the face, it is
> naturally more protected than a PDA or laptop screen. PDA screens are
> relatively large and vulnerable surfaces in a mobile environment.
> Since the PDA may be stored in a pocket, its screen can easily be
> subjected to large forces if the user sits on it or places a large
> object on his lap. Another problem with PDA-sized screens is that
> they must be supported by a hand. In fact, most PDA interfaces
> require the use of both hands (one for support and one for the stylus)
> and both eyes. If a PDA user attempts to use the interface when
> walking, much of his attention will be devoted to compensating for the
> mechanical shock of the movement. Thus, both the user's physical and
> attentional resources can be consumed by the PDA. On the other hand,
> a wearable with a head-up display demands much less of the user
> while mobile.
>
> A head-worn display can also provide much better ergonomics than a
> desktop, PDA, or laptop screen. Instead of requiring the user to sit
> in an upright position with hands, neck, and back in the proper
> location, the user of a head-worn display has much more freedom. I,
> for example, often lay on the sofa in my office to write my papers.
> Such freedom can be a release from occupational pain for sufferers of
> back, neck, and hand injuries. (One unfortunate side effect, though,
> is that visitors sometimes initially think I am sleeping when they
> enter my office for their appointment).
>
> Another ergonomic benefit of several of the modern head-worn displays
> is their adjustable focus. Frequent users of desktops and laptops are
> vulnerable to "computer vision syndrome" (CVS) due to the eye being forced
> to attempt to focus at a near distance for extended periods of time,
> Symptoms include headaches, loss of focus, burning/tired eyes, double
> vision, blurred vision, and neck and shoulder pains. Some
> optometrists even consider such computer use to increase the risk of
> myopia (near-sightedness) in children. According to
> Prio \cite{Priowebsite} and Bausch and Lomb \cite{Bauschwebsite},
> makers of equipment for CVS, computer vision syndrome is due to the
> difference in the resting point of accommodation (RPA) and the
> distance users have to focus their eyes to read a computer screen.
> The RPA is the distance at which the eyes focus by default (around 76
> cm or 30 inches). With an adjustable focus screen, a head-worn display
> user can vary his focus from a near depth to the RPA to even an
> effective infinite depth depending on what provides the user with the most
> comfort.
>
> Head-worn displays also have an advantage over PDAs in the amount of
> power they require. In order to be useable, a PDA must be viewable
> from many different angles, even if the perceived image subtends the
> same amount of effective visual arc as a head-up display. However,
> a head-worn display is mounted so that its light is relatively
> focused into the eye. Thus, head-worn displays naturally require less
> power than a PDA screen. To illustrate the idea, the PDA might be
> thought of as a flashlight which casts its light over a wide area
> whereas the head-worn display might be thought of as a slide projector
> that tries to provide a brilliant image in a limited area.
>
> Head-worn displays offer some unique features over PDA and laptop
> screens. Since the display is worn close to the eye, spying on the
> user's screen without his knowledge is nearly impossible. Combined
> with appropriate sensing, head-worn screens can be used to create a
> real-time overlay of graphics on to the physical world. In addition,
> accelerometers or a magnetic compass can be used to create a virtual
> head-up display; as the user rotates his head, the image in the
> display pans through a virtual image rendered in a ring around the
> user's body \cite{billinghurst,macintyre}.
>
> Head worn displays can also be less socially obtrusive than many
> alternatives. For example, a cellular phone call can be announced
> discretely with its caller ID in the user's display instead of an
> insistent and uninformative mobile phone ring. As another example,
> instead of needing to look away from his interviewee to put pen to
> paper, a reporter can maintain eye contact while typing notes to his
> display. Such subtlety can help avoid derailing the discussion as the
> artifacts of the interviewer's notetaking (e.g. notepad, pencil,
> writing, etc.) are no longer visible.
>
> *If head-worn displays have so many advantages, why haven't they
> penetrated the market?* or *Why aren't they here yet?*
>
> While head-worn displays have a history going back to the earliest
> efforts in computer graphics, only recently have small, mobile
> computers and appropriate communications infrastructure been developed
> that would benefit from their use. Now that the concepts of SMS
> typing, game playing, and photography on cellular phones are becoming
> popular, there will be greater impetus to adapt head-worn displays to
> those markets. In addition, wide area wireless Internet access is
> beginning to become reliable, and the public will begin to embrace the
> idea that they do not have to be limited to their office to have
> access to full-scale computing support.
>
> However, microdisplay manufacturers still face difficult challenges.
> For example, the display's field of view must be balanced against the
> amount of visual area occluded by the display's support hardware.
> Cost, brightness, contrast, power, resolution, social obtrusiveness,
> and clarity are only some of the factors that manufacturers must
> consider. While the state of the art has limited manufacturers in
> these trade-offs in the past, recent studies have shown a beginning
> maturity in the field, both in hardware and experimental practices.
>
> In the Journal of Optometry and Vision Science, Sheedy and Bergstrom
> report that users performed very similarly on paragraph reading,
> letter counting, and word search tasks when using a monocular 800x600
> resolution display (e-case by InViso) versus hard copy or a 15" flat
> panel display. \cite{Sheedy} In some cases, the monocular display
> actually outperformed the other display methods, but the results for
> these tests were not statistically significant. Similarly, a
> binocular display (e-shades by InViso) tested had slower or equal
> performance rates on the tasks when compared to the monocular display,
> hard copy, or the flat panel, but the results were not statistically
> significant. In previous experiments, older head-worn displays did
> not perform as well as desktop monitors or hard copy. In this study, the
> authors attribute the current favorable comparison to improved display
> resolution, partial instead of full immersion, and several other
> effects best described in the original paper.
>
> While Sheedy and Bergstrom's experiment shows the promise of the image
> quality of the newer wearable displays, Laramee and Ware have been
> exploring the effects of various backgrounds on task speeds when using
> a monocular display. In their paper "Rivalry and Interference with a
> Head Mounted Display," Laramee and Ware experiment with both a
> see-through monocular display and an opaque monocular display. Users
> were required to scan through a table of items and prices and use a
> mouse to click on a specified price given a question such as "What is
> the price of lettuce?" While performing this task, the users either
> saw a bookshelf or a television playing a movie in the background.
> The authors found statistically significant evidence for both
> binocular rivalry (what one eye sees affects the other) and
> interference (the background in a see-through display can conflict
> with what the user is doing). However, the effects were not as strong
> as the authors expected, especially in the case with the static
> background. While there are many aspects that can be further explored
> (adjusting brightness, contrast, and transpareny levels; using higher
> resolution than the 450x266 IO Display Systems i-glasses in the
> experiment; exploring focus effects with the TV background; exploring
> other user tasks; etc.), this experiment shows a desire to examine
> more complex tasks with head-worn displays. More such
> experiments from the research community are needed to help display
> manufacturers and wearable software providers tune their products and
> overcome limitations to head-worn display use.
>
>
> URLs:
> http://www.prio.com/consumers/problem.shtml
> http://www.bausch.com/us/vision/products/magnifiers/cvs.jsp
>
> References:
>
> James Sheedy and Neil Bergstrom. "Performance and Comfort on Near-Eye
> Computer Displays." Optometry and Vision Science, 79(5), May 2002, pp.
> 306-312.
>
> Robert Laramee and Colin Ware. "Rivalry and Interference with a Head
> Mounted Display." ACM Trans. on Computer Human Interface (TOCHI),
> 9(3), September 2002, pp. 238-251.
>
> Mark Billinghurst and Thad Starner. "Wearable Devices: New Ways to
> Manage Information." IEEE Computer, 32(1), January 1999, pp. 57-64.
>
> <need appropriate MacIntyre/Feiner article>
>
> ============================================================
>
> --
> Subscription/unsubscription/info requests: send e-mail with subject of
> "subscribe", "unsubscribe", or "info" to 
> Wear-Hard Mailing List Archive (searchable): http://wearables.blu.org
> Please, *PLEASE* don't subscribe through a forward/expander/false domain
>
--
Subscription/unsubscription/info requests: send e-mail with subject of
"subscribe", "unsubscribe", or "info" to
Wear-Hard Mailing List Archive (searchable): http://wearables.blu.org
Please, *PLEASE* don't subscribe through a forward/expander/false domain
From Wear-Hard Mailing list Archive (WH)
Maintained by R. Paul McCarty
Archive created with babymail