Virtual Research Flight Helmet
More actions
| Virtual Research Flight Helmet | |
|---|---|
| Basic Info | |
| VR/AR | Virtual reality |
| Type | Head-mounted display |
| Developer | Virtual Research |
| Manufacturer | Virtual Research |
| Release Date | 1991[1] |
| Price | US$6,000 (starting retail price)[2] |
| Display | |
| Display | Two LCD screens, 6.9 cm[1] |
| Resolution | 240 x 120 pixels (Deutsches Museum);[1] 208 x 139 color triads per LCD (Watson et al.)[3] |
| Image | |
| Field of View | 100 degrees diagonal (Deutsches Museum);[1] 75.3 degrees horizontal x 58.4 degrees vertical per LCD (Watson et al.)[3] |
| Optics | |
| Optics | LEEP wide-angle optics from LEEP Systems[1] |
| Ocularity | Binocular |
| Connectivity | |
| Connectivity | Two NTSC video inputs[4] |
| Device | |
| Weight | 1.67 kg[1] |
The Virtual Research Flight Helmet is a VR headset created by Virtual Research.[5] It is a head-mounted display dated to 1991, made by the Sunnyvale, California company, and it combined wide-angle LEEP optics with two small color LCD panels.[1][5]
It uses LEEP optics.[6] The Deutsches Museum, which holds one in its collection, gives the headset a 100-degree diagonal field of view, a resolution of 240x120 pixels and a weight of 1.67 kg, and lists its price as $6000.[1]
Its displays were low resolution LCDs taken from Sony portable TVs. When those TVs were discontinued, Virtual Research was forced to cease production of the Flight Helmet.[7] In his 2018 Oxford thesis on the history of virtual reality, Tobias Bowman writes that it was mentioned in around 80 academic publications between 1990 and 1995, more than any other HMD of the period.[7]
History
The Flight Helmet was the flagship HMD of Bruce Bassett's company Virtual Research.[7] The company later described itself as "a pioneer in headmounted and custom display solutions since 1991".[8] According to the VR history site V-Rtifacts, by 1991 the Flight Helmet was the third HMD to use LEEP (Large Expanse Extra Perspective) optics from Eric Howlett's company. The first two were a custom HMD that VPL Research built for NASA in the mid-1980s at a cost of more than $100,000, and VPL's own Eyephones of 1989.[6] A 1993 MITRE Corporation survey of HMDs for virtual reality listed the Flight Helmet, made by Virtual Research in Sunnyvale, California, as one of several commercially available HMDs, alongside the Eyephone from VPL Research, the Cyberface from LEEP Systems and an HMD from the Virtual Reality Group of Vienna, Virginia.[5]
Bowman's thesis notes that of the 44 companies that claimed to sell VR hardware in 1994, only 10 visibly did so, and it describes Virtual Research as the most successful of them. Sales figures that Bassett provided to Bowman show the company's HMD sales growing from 11 units in 1991 to 107 in 1995. Bowman writes that these would have been a mix of Flight Helmets, EyeGen and VR4 models, and that they far outsold the products of any other VR manufacturer of the era. Its customers included universities, private organisations and rival VR companies such as Division, Fakespace, General Reality, Cybercube and Argus VR.[7] Bowman attributes part of the company's success to the comfort and ease of use of the Flight Helmet, which could be worn with eyeglasses.[7]
The helmet depended on a supply of consumer display panels. Bowman writes that no VR company of the time was wealthy enough to make its own LCD panels, so the screens were taken from portable televisions and used in LEEP, VPL, Virtual Research and Virtuality HMDs.[9] V-Rtifacts similarly notes that the LEEP-based helmets were built by stripping down small handheld consumer TVs, and that Epson's entry into the small (1.3-inch) LCD market in 1992-1993 ended the age of LEEP helmets.[6] Later Virtual Research devices used smaller lenses and a reduced field of view to save weight and cost; according to the Deutsches Museum, by 1994 the LCDs in the VR4 had twice the resolution at half the size.[1]
Design and hardware
Optics and field of view
The Flight Helmet uses 6.9 cm LCD screens with LEEP Systems' wide-angle optics.[1] The MITRE report explains that the LEEP optics, designed by Eric Howlett for viewing stereoscopic photographs, are essentially a wide-angle magnifier that compresses most of the image information into the central part of the view, and that they can provide a horizontal field of view of up to 140 degrees. Setting the two optical axes parallel reduces the field of view but increases binocular overlap; the Flight Helmet, with parallel axes, achieves a total field of view of 100 degrees, about 40 degrees less than LEEP Systems' Cyberface 2.[5] Benjamin Watson and colleagues reported a vertical field of view of 58.4 degrees and a horizontal field of view of 75.3 degrees for each of the helmet's two LCDs.[3]
The LEEP optics produce distortion that grows with distance from the optical axis. The MITRE report describes LEEP distortion as severe pincushion distortion that can be corrected in the generated graphics at a processing cost.[5] Watson and colleagues described the distortion in the Flight Helmet as mild enough that most users do not notice it unless told. In their 1997 study, correcting it in software reduced the frame rate too much, so they left it uncorrected.[3]
Because the LCD panels were physically too wide to match typical inter-pupillary spacing, the left and right images did not completely overlap. The graphics system had to render non-overlapping images for each eye, or prisms had to be fitted in the eyepieces.[6] The partial overlap produced an image wider than the normal 4:3 aspect of NTSC video. Users who wanted full overlap, or who ran the helmet monoscopically, needed 3M Press-On Fresnel prisms to shift the images horizontally into alignment.[2] Watson and colleagues used adhesive plastic Fresnel lenses supplied by Virtual Research on the last optical elements to run the helmet in a biocular mode, sending the same image to both video inputs.[3]
Displays and resolution
Sources give different figures for the display resolution. The Deutsches Museum lists 240x120 pixels,[1] V-Rtifacts describes 240 horizontal pixels spread over a 100-degree field of view,[6] and papers by Watson and colleagues describe each LCD as an array of 208 x 139 color triads.[3] The MITRE report states that the Flight Helmet used 3-inch LCDs, which gave a magnification of about 9.6x and magnified virtual pixel sizes of 2.4 mm x 5 mm. It noted that the individual color pixels were discernible and that the image became "a collection of colored blocks rather than a smooth, continuous picture."[5]
Watson and colleagues reported an average horizontal angular resolution of 21.74 arcminutes, equal to a Snellen fraction of 20/435. Because of the LEEP distortion, resolution was about 17.76 arcminutes (20/355) at the center of the display and 23.46 arcminutes (20/469) at the edge.[3] V-Rtifacts wrote that the low pixel count made "each pixel seem like a floating football from the wearer's perspective".[6]
Inputs, weight and ergonomics
The Flight Helmet takes two NTSC video signals as input and weighs 3.7 pounds, according to a 1997 paper in Presence.[4] The Deutsches Museum gives its weight as 1.67 kg.[1] In the Georgia Institute of Technology experiments reported in that paper, head motion was tracked with a separate Polhemus Isotrak II, and Silicon Graphics scan-conversion hardware and software turned the workstation output into an NTSC signal for the helmet.[4] V-Rtifacts described the helmet as adjustable, comfortable and rugged, and wrote that a rear-exiting cable acted as a counterweight that balanced the HMD.[6]
Focus and convergence
The MITRE report states that Virtual Research gave figures for the distance to the virtual image plane in the Flight Helmet similar to those of the VPL Eyephone, whose image plane was calculated at about 0.4 m. It also reports that both LEEP Systems and Virtual Research said in private communication that they had not paid attention to the conflict between accommodation and convergence when designing their systems. The authors concluded that this limited the ability of such HMDs to present spatially correct images.[5]
Use in research
The Flight Helmet was widely used in academic and government VR research in the early and mid-1990s.[7][3] NASA Ames made use of it, and later of the V4, V6 and V8 HMDs from Virtual Research, well into the 1990s.[7] Bowman notes that Virtual Research Flight Helmets remained in use in a small number of VR research projects into the 2000s, including at Ames.[10]
At the Fraunhofer Institute for Computer Graphics (IGD) in Darmstadt, Germany, VR research began in 1991 with a government-funded project called "Vis-à-Vis", which paid for a Silicon Graphics 3000, a VPL DataGlove and a Flight Helmet. The institute later replaced the Flight Helmet with the VR4.[11]
At Georgia Tech, Benjamin Watson, Neff Walker, Larry F. Hodges and colleagues used the Flight Helmet in a series of user studies on managing level of detail in the periphery of head-mounted displays, published in 1997 in Presence and ACM Transactions on Computer-Human Interaction. They called it "the widely used Virtual Research Flight Helmet".[3][4] The MITRE Corporation included it in its 1993 assessment of HMD technology for immersive virtual reality, prepared with support from Rome Laboratory at Griffiss Air Force Base. The authors judged the images of LCD-based HMDs such as the Flight Helmet unacceptable because of their low resolution, and concluded that major advances in HMD technology were required to achieve adequate immersive virtual reality.[5]
Legacy
A Flight Helmet is in the collection of the Deutsches Museum in Munich, which describes it as competitively priced for its era.[1] Writing on V-Rtifacts in 2010, the site's author called it "the ultimate head mounted display", apart from its need for modern high-resolution LCD panels.[2]
See also
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 "Virtual Research Flight Helmet". Google Arts & Culture. Deutsches Museum. https://artsandculture.google.com/asset/virtual-research-flight-helmet/1AGrF3Gb56sCHw. Retrieved 2026-09-27.
- ↑ 2.0 2.1 2.2 "Flight Helmet - Redux". V-Rtifacts. 2010-12-08. https://vrtifacts.com/flight-helmet-redux/. Retrieved 2026-09-27.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 Benjamin Watson, Neff Walker, Larry F. Hodges, Aileen Worden (1997). "Managing Level of Detail Through Peripheral Degradation: Effects on Search Performance with a Head-Mounted Display". ACM Transactions on Computer-Human Interaction, vol. 4, no. 4 (author manuscript on arXiv). https://arxiv.org/pdf/2507.13660. Retrieved 2026-09-27.
- ↑ 4.0 4.1 4.2 4.3 Benjamin Watson, Neff Walker, Larry F. Hodges, Martin Reddy (1997). "An Evaluation of Level of Detail Degradation in Head-Mounted Display Peripheries". Presence: Teleoperators and Virtual Environments, vol. 6, no. 6 (author manuscript on arXiv). https://arxiv.org/pdf/2506.21441. Retrieved 2026-09-27.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 Paul J. Hezel, Harry Veron (February 1993). "Head Mounted Displays for Virtual Reality". The MITRE Corporation, report M93B0000015 (via Defense Technical Information Center). https://web.archive.org/web/20150223050243/http://www.dtic.mil/dtic/tr/fulltext/u2/a263498.pdf. Retrieved 2026-09-27.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 "Take Flight in the Virtual World". V-Rtifacts. December 10, 2009. https://vrtifacts.com/take-flight-in-the-virtual-world/. Retrieved 2024-05-01.
- ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 Bowman, Tobias (2018). "Fate amenable to change: a technical and social history of Virtual Reality in the United States of America, from 1965 to 2005". ORA (Oxford University Research Archive). p. 177. https://ora.ox.ac.uk/objects/uuid:621e4934-2a78-47f7-84f2-6541bc095bd3/files/m5c8a869648701a6b715d20f9f08c3e6e. Retrieved 2024-05-23.
- ↑ "Virtual Research Systems, Inc.". ACM SIGGRAPH History Archives. ACM SIGGRAPH. https://history.siggraph.org/exhibitor/virtual-research-systems-inc/. Retrieved 2026-09-27.
- ↑ Bowman, Tobias (2018). "Fate amenable to change: a technical and social history of Virtual Reality in the United States of America, from 1965 to 2005". ORA (Oxford University Research Archive). p. 167. https://ora.ox.ac.uk/objects/uuid:621e4934-2a78-47f7-84f2-6541bc095bd3/files/m5c8a869648701a6b715d20f9f08c3e6e. Retrieved 2026-09-27.
- ↑ Bowman, Tobias (2018). "Fate amenable to change: a technical and social history of Virtual Reality in the United States of America, from 1965 to 2005". ORA (Oxford University Research Archive). p. 256. https://ora.ox.ac.uk/objects/uuid:621e4934-2a78-47f7-84f2-6541bc095bd3/files/m5c8a869648701a6b715d20f9f08c3e6e. Retrieved 2026-09-27.
- ↑ Wolfgang Felger, Martin Göbel, Dirk Reiners, Gabriel Zachmann (2024-03-21). "VR Research at Fraunhofer IGD, Darmstadt, Germany". arXiv. https://arxiv.org/abs/2403.01629. Retrieved 2026-09-27.