Virtual Research Systems FS5i User Manual

User’s Guide

FS5i

Virtual Research Systems, Inc.

December, 1995
The information contained in this publication is believed to be reliable, but Vir-

tual Research Systems, Inc. makes no warranties as to its accuracy or com­pleteness.

Copyright 1995 Virtual Research Systems, Inc. All rights reserved.

Virtual Research Systems, Inc.
2326 Walsh Ave.

Santa Clara, CA 95051

phone: [phone]

fax: [phone]

e-mail:

[e-mail]

FS5i

The

FS5i

is the integration of our top of the line FS5 HMD and our
FSCAN scan converter. The result is an HMD that accepts multiple signal
formats without the headache and expense of additional cabling. The

FS5i
maintains all of the functionality of the two separate devices, incorporating them
into a single, rack mountable enclosure. A new feature of the

FS5i

is a VGA

monitor output that replaces the field sequential monitor output of the

FS5.

This
allows the user to drive the HMD and a monitor without a VGA splitter or
additional cabling.(monitor out not available with field sequential input format.)

In addition, selectors for input formats and mono/stereo have been

relocated to the front panel.

The top cover of the enclosure need only be

opened to fine tune color

adjustments.(normally

not needed)

Initially, your

FS5i

will be shipped with separate manuals for the FS5 and

FSCAN. The functionality of the

FS5i

is the same as the separate units with the

above exceptions.

By following the guidelines in the separate manuals, one

should find the setup of the

FS5i

HMD to be simpler. A new, integrated

FS5i
manual will be shipped to you as soon as it is available. If you have any
questions or problems please contact Virtual Research for prompt assistance.

Contents

ii

TABLE OF CONTENTS

INTRODUCTION TO THE FS5

SAFETY ISSUES

FS5 CONTROL BOX

Inputs

Video Input
outputs

MECHANICAL ADJUSTMENTS

Donning the

FS5

Interpupillary Distance (IPD)

Fore/Aft motion of shell
Display Height Adjustment
Overlap Adjustment

Ratchet Knobs
Headphones

Cable Positioning

OPTICS

POSITION SENSORS

Traeker Mounting

Reducing Tracker Jitter

PIN OUT INFORMATION

SYSTEM CONFIGURATION INFORMATION

23

Intergraph Platforms

23

1

2

14

14
15
15
16

16
17
17

17

18

19

19

21

22

Contents iii

Division

ProVisionlO

System Configuration
SGI Reality Engine System Configuration
SGI Indigo2 Impact System Configuration
Other Systems and the F-Scan Converter

THE F-SCAN CONVERTER

26

TROUBLESHOOTING

27

24
24
25
25

ChaDter

1 Introduction 1

Chapter 1

Introduction to the

FS5

FS5

is our new high performance head mount display (HMD) . At the heart of
the product are 1” cathode ray tubes (CRTs) capable of resolution and image
quality far superior to any available flat panel displays. The CRTs are black and
white tubes which run field sequentially; red, green and blue are created by
color shutters mounted in front of the CRTs. Although most users will drive
the

FS5

to VGA resolution, the CRTs are capable of up to 800 pixels horizon-

tally.

The

FS5

optical system excels as well. A custom design using

aspheric

sur-

faces on plastic elements allows us to achieve a

55”

field of view (FOV) while
maintaining sufficient eye relief for glasses wearers. By using plastic, we avoid
the weight problems of glass elements.

Mechanically, the FS5 retains many features developed and perfected in our
LCD product, the VR4. The rugged front shell protects the display components
and requires only two adjustments--interpupillary spacing and fore/aft posi­tioning.The headband is a proven performer with thousands of hours of trou­ble free experience in the VR4. The high flex cable has an extruded jacket for

abrasion resistance.
Audio rises to a new level with the FS5. These Sennheiser closed cup head-

phones are the best compact headphone we have found.Whether your source
is simple monaural cues or top-of-the-line stereo, these headphones
will perform.

The FS5 control box has superior functionality as well.A set of front panel
LEDs

give instant status information. Brightness and contrast adjustments that
control both eyes together are also available on the front panel. Full right and
left RGB setup and gain adjustments are also easily accessed inside the control
box if fine tuning is desired.

Standard field sequential input is available from several image generators, in-

cluding SGI and Division. A similar field parallel format is available from

In­tergraph platforms. Appropriate connectors are easily accessible at the control
box rear panel.

For other signal sources, an optional converter is available. The F-Scan Con­verter accepts either RS-170 RGB or

6OHz

VGA stereo signals and drives the

FS-5 directly.
The true test of any product is not the features list, but how it performs in your

application. We expect that the blend of features designed into FS5 will work
well for you. But if you have any questions or problems or special design re­quirements, please give us a call. We’ll do whatever we can resolve your ques­tions and make your application successful.

Chapter 2 Safety Issues 2

Chapter

2

Safety Issues

We take pride in building a safe product that will satisfy your requirements.
But the nature of our product--an electronic display device that you wear on
your head--creates the potential for problems. We strive to understand and
minimize the safety hazards associated with our head mount displays.

As an HMD user, you should understand those hazards too.

With that under­standing, please make an informed decision about using this or any head mount
display product.

Blocked vision and hearing

By its nature, a head mount display blocks the user’s vision and hearing. The

danger of tripping over cables or other obstacles becomes a real concern while
immersed in the virtual world. As system manager, you must provide an envi­ronment that does not allow the. HMD user to fall or otherwise injure
him/herself. As a system user, you must survey your physical environment be­fore entering the virtual environment to avoid problems. We recommend using
FS5

only while seated to avoid tripping hazards.

Eyestrain and other optical effects

FS5

will cause eyestrain if the interpupillary distance (IPD) is set incorrectly.
Like all head mounts, it is likely to cause some eyestrain effects even when cor­rectly adjusted. This eyestrain stems from several causes, with perhaps the
most significant being the fixed focal plane which conflicts with the variable

depth cues present in the imagery. There is no technology we are aware of that
corrects this conflict.Other potential sources of eyestrain include optical aber­rations, distortion, mismatch of computer imagery with mechanical configura­tion and display mismatch.

If you experience noticeable eyestrain, review and correct your mechanical ad-

justments and software configuration. If eyestrain persists, limit or end your

use of this device.

Lice/other pest transmission between users

Although we have not had any instances of user’s reporting lice transmission to

us, there has been at least one anecdotal report of lice transmission in a public

Chapter 2 Safetv Issues 3

use HMD. There are sprays available that will kill lice on furniture and cloth-

ing. Two of these are RID and A-200. Both are available in drug stores. We
don’t have information on the effectiveness of these sprays on

HMDs

and en­courage you to research this if you are considering a multiple user application.
These sprays are hazardous and you need to judge the benefits vs. risks of us­ing them. Remember to read and follow the manufacturer’s directions.

Alcohol wipes are useful for cleaning the HMD between users. Alcohol will
remove skin oil and makeup that have transferred to the HMD. As far as we
know, alcohol has no effect on lice.

Electrical Shock Hazard

The desktop power supply produces

12V, -

12V and 5V DC.

All three voltages
are present in the control box. The HMD cable carries the 12V power to the
HMD. These voltages are too low to represent a significant hazard, even with
the control box open to make color adjustments.

The enclosure at the rear of the HMD contains high voltage circuitry required
for the CRTs. This enclosure should be opened only by trained, authorized
technicians.The voltage is sufficient to give a significant shock if contacted.
The voltage is also sufficient to arc across a few millimeter gap to any conduc­tive surface--like a finger or tool. In our experience the shock from this voltage

is bothersome, but not dangerous because the current level is quite low. How­ever, under worst case circumstances the effects would undoubtedly be more
severe (e.g. pacemaker users, etc.).

The top bar of the headband contains a cable bundle that carries these high volt­ages to the front of the HMD. Do not cut, drill, clamp or otherwise damage this
portion of the headband.

The front portion of the HMD consists of two display units within a shell.

The
wiring from the headband to the display units and the display units themselves
have the same voltage levels described above. There are no user accessible ad-

justments at the front of the HMD and no attempt should be made to insert fin-

gers, tools or other potentially damaging/conductive items into the front shell.

The shell should be removed only by trained, authorized technicians.

Extremely Low Frequency (ELF) and Very Low Frequency

(VLF) Emissions

Magnetic fields generated by electronic devices (Televisions, toasters, shavers,
household wiring, high voltage lines,

-etc,

etc, and

HMDs)

have been reported

to cause a number of severe health problems, including leukemia.

There is a

great deal of controversy at this time regarding the validity of these studies.

A
number of other studies have found no correlation between these emissions and
health risks.

Test equipment, a standard procedure and test limits for ELF and VLF

emis-

Chapter 2 Safety Issues 4

sions for computer monitors have been developed in Sweden. While this test
seems relevant to head mount displays, the equipment is unsuitable for meas­uring the fields around miniature displays. There are no standard test proce­dures, equipment or standards for electronic devices other than computer
monitors.

Because there are so many unknowns surrounding this topic, we elected to
contract an expert in the field to develop test equipment and calibrate that
equipment for us. We have developed procedures for measuring the fields gen­erated by our products using that equipment. After measuring the fields gener-

ated by our components, we add shielding and/or relocate components to mini-

mize the fields. This seems to be the prudent approach in view of the vast lack

of solid information in this area.

X-Ray Emissions

CRTs are capable of generating x-ray emissions under some circumstances.
Our CRTs operate at voltages below levels that produce x-ray emissions. The
CRT production process includes testing to verify this. The U.S. Food and
Drug Administration regulates CRT products to ensure adherence to x-ray emis­sion standards. Our product information has been submitted to the FDA for re­view.

Further Information

If you have questions about any aspect of head mount display product safety,
please feel free to contact us directly. Our address, phone number and e-mail

address are listed at the front of this document.

.

Chapter 3 Control Box 5

Chapter

3

FS5

Control Box

Box

Inputs

FS5

control box inputs are located on the rear panel:

fi

3

VlDEO

INPUT

RIGHT

LEFT

I PION

RIGHT

LEFT I MONO

Control Box Rear Panel

Audio

The audio jack is a standard stereo

3.5mm

mini phone jack. The control box
passes the audio signal through directly to the FS5 headphones; there is no am­plification or audio adjustment in the control box. Audio signal level supplied
to the control box should be the same signal that would be supplied directly to
stereo headphones.

Power

The control box requires

+12VDC,

-12VDC and

+SVDC.

A universal power

supply comes with FS5. The power plug on the FS5 is a 5 pin DIN plug.

CAUTION: IT IS EASY TO DESTROY YOUR

FSS--SIMPLY

PLUG

IN THE WRONG POWER SUPPLY AND TURN IT ON.

TO AVOID THIS UNHAPPY EXPERIENCE, ALWAYS CHECK FOR

THE COLOR MATCHED BAND ON THE POWER SUPPLY PLUG
AND THE COLOR PATCH ON THE CONTROL PANEL. IF THE
POWER SUPPLY DOESN’T HAVE A MATCHING BAND, DON’T
PLUG IT IN!

Chapter 3 Control Box 6

Because the 5 pin DIN plug is used on many power supplies, there is a real

hazard of plugging the wrong power supply into the

FS5

control box. To re-

duce the risk of this, we have added a

REID

colored band to the

FS5

power

supply and a YELLOW colored band to the F-Scan power supply. Always

check for correct color matching before plugging in a power supply to avoid

making an expensive mistake.

Power SupplyQuick Identification

colored band

RED BAND --

FS5

Power Supply
YELLOW BAND -- F-Scan Power Supply
No Band-- Don’t use!

As a further verification of power

supplies,

compare the label to the copies below

be-

FS5

Power Supply

F-Scan Power Supply

One particular example of this problem is the Polhemus Fastrak which also uses
a 5 pin DIN plug. The Fastrak power supply outputs a higher voltage and can
damage the unit