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The Electronic Broadsheet


The viewing area of the 2k monitor is almost as high as a broadsheet newspaper and a little wider. When seeing the display for the first time most people are struck by its size and resolution. The display is the driving force behind this project and is state-of-the-art technology. It is a unique device, but its physical properties leave much to be desired. It may be suitable for a Chinese wall newspaper, but it will not fit on your desktop.

6.1 Physical Dimensions and Setup

The monitor measures 694x673x760 mm (w/h/d) and weights ca 98 kg [SONY 89] . To make this huge piece of glass and metal as flexible and portable as paper is impossible; at least three people are required to move it. However, one can imagine several physical setups that improve the reader's ergonomics.

The monitor is currently hosted by a custom-built stand that came into being prior to the Newspace project. Below the monitor is a retractable shelf onto which the keyboard and mouse is placed. The secondary screen has a similar lower stand.

6.1.1 The Ideal Physical Setup

A servo-powered crane that can move the monitor in three dimensions and also adjust the angle of the screen surface would be the ultimate setup to overcome the bulkiness of the display, see figure

9. The reader could "power-steer" the monitor with the tip of a finger to get a close-up view of a certain article, or move it away to get an overview. The crane provides a dynamic environment that would be similar to moving the paper around; the operation resembles how readers move newspapers. Unfortunately, this solution is mechanically too advanced for the scope of the project.

6.1.2 The Compromises

By making the reader move in three dimensions instead of the bulky display, the problem is simplified a lot. This leaves only the tilt angle to be adjusted, and that is a reasonably simple operation that could be implemented. However, the solution is still peripheral to the main goal of the project, and I believe the resources required are better invested in other parts of the project.

By setting a fixed tilt angle, the problem is further simplified. This solution seems to work for normal computer screens; although it is possible to adjust the tilt, it is rarely done. Instead, readers of different heights adjust their chairs to obtain a better reading position. The favorite angle for computer displays is close to the vertical one. This is also the intended angle for the 2000-line monitor. The display is not designed for safe operation if the tilt exceeds a certain angle. Contaminations inside the tube may cause the electron guns to short-circuit and cause damage to the display--and possibly to the reader!

Newspapers, on the other hand, are safely operated at any inclination. Most people prefer an angle somewhere between the vertical and horizontal to keep all articles within a reasonable distance and to minimize the "keystone" effect. See figure 10.

Ergonomics is an increasingly important field for computer system designers. A workstation should be constructed with the human body in mind. When trying to tilt the 2k monitor, one faces severe ergonomic challenges. As the tilt angle increases, the reader has to sit relatively higher. Also, as one will see from figure 10, the more tilt, the less leg room.

As a result of these factors, the monitor has not been tilted. Several attempts have been made, but it has not been possible to find a solution that fulfills both technical and ergonomic requirements,

6.1.3 The Keyboard

Only a pointer device is required to read and navigate in the newspace, but a keyboard is supported for other uses of the computer, e.g. replying to electronic mail messages. The stand that supports the workstation was designed with a keyboard in mind; it contains a retractable shelf under the monitor shelf.

6.1.4 The Mouse

Currently, a mouse is being used as the pointer device for the X11 workstation. It has turned out to be annoying. Since the size of the screen pointer is small compared to the total screen size it is easy to lose track of the pointer.

The bigger cursor used in the Electronic Broadsheet improves upon this, see figure 11, but I believe it is intrinsically harder to relate mouse movements to pointer movements on larger screens, even if the screen size/pointer size ratio is constant. The distance between the mouse and the cursor is much longer, and the ratio between the mouse movement and the cursor movement is higher.

For a discussion of alternate input devices, see chapter 10.

6.2 Hardware

The hardware configuration that drives the displays consists of a Sun Sparcstation 370 with 32Mb of RAM. The Sun hosts a VME frame buffer from Univision, model UDC-4012. The frame buffer drives the main monitor, a Sony DDM-2801C, which features 2048 lines of resolution and a 60 Hz progressively scanned refresh.The second monitor is a standard 1k color display.

6.3 Software Platform

The X Window System (X11) has established itself as the standard window system on UNIX workstations [Scheifler, Gettys 87]. To run X11 applications one needs a server application that stands between the client applications and the hardware, i.e., the display, keyboard and pointer device.

The source code for MIT's sample server is freely available and was ported to the Univision board last year. The server allows the previously described configuration to be used as an X11 workstation and makes large amounts of existing software available. It also provides a standardized interface to the screen and input devices.

An alternate software platform would have been to interface the frame buffer directly. This would have opened for the use of a graphics acceleration chip in the Univision that the X11 server currently ignores. Also, the frame buffer hardware supports 12 bits per pixel, while the X11 server runs in a 8 bits per pixel mode. However, many of the graphics primitives that come for free with X11 would have to be written for the Univision.

At some point, a decision to implement the Electronic Broadsheet under X11 was made. X11 sets some constraints and is not always optimal in terms of performance, but I believe the functionality achieved in the current system would not have been possible in any other way unless many more resources had been allocated.

6.4 The Second Screen

The Sun host machine has a console monitor with a resolution of 1152x900 pixels. Since the map is a distinct self-contained unit it was decided to put the map on the secondary screen; an optimal solution with regard to screen real-estate.

After the above described solution was implemented, some have argued that the main screen should contain the map instead of using the second screen since moving between two screens of different character could become a distraction. Another option argued for is to use the second frame buffer in the double-buffered Univision and switch back and forth between the two. The last solution would make room for a large map, but the reader would not see the map and the newspace at the same time.

I did not find any of these ideas compelling enough to reimplement the map for the 2k monitor. However, the Newspace project aims at making news presentation scalable to any device, and chapter 11 discusses some issues that came up when porting the system to a one-screen system with a tabloid-sized monitor.

6.5 Implications for the User

The described setup has been used as an X11 workstation for more than a year now. The color display has four times more pixels than an average X11 workstation, and it is used differently from a normal workstation. This difference cannot be measured in square centimeters only. When using the large screen, screen space management will shift emphasis from screen area conservation to screen overview. The overlapping windows found in most window systems are replaced by a "bulletin board". This is an important observation that will change the way people use and write software.

6.1 - Physical Dimensions and Setup
6.1.1 - The Ideal Physical Setup
6.1.2 - The Compromises
6.1.3 - The Keyboard
6.1.4 - The Mouse
6.2 - Hardware
6.3 - Software Platform
6.4 - The Second Screen
6.5 - Implications for the User

The Electronic Broadsheet - 30 JUN 95
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