Mr. Clarence E. Rash Profile

Clarence E. Rash

at US Army Aeromedical Research Lab

SPIE Involvement:

Track Chair | Author

Publications (54)

SPIE Journal Paper | 19 December 2018 Open Access

Modeling perceptual color confusion of helmet-mounted display symbology as a function of see-through contrast

Thomas Harding, Jeffery Hovis, Clarence Rash, Michael Smolek, Morris Lattimore

OE, Vol. 58, Issue 05, 051804, (December 2018) https://doi.org/10.1117/12.10.1117/1.OE.58.5.051804

KEYWORDS: Head-mounted displays, Chemical vapor deposition, RGB color model, Color vision, Distance measurement, Optical engineering, Visualization, Visual process modeling, Absorption, Heads up displays

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Proceedings Article | 2 May 2018 Presentation + Paper

HMD daylight symbology: color discrimination modeling

Thomas Harding, Jeffery Hovis, Clarence Rash, Michael Smolek, Morris Lattimore

Proceedings Volume 10642, 1064203 (2018) https://doi.org/10.1117/12.2304049

KEYWORDS: Head-mounted displays, Color vision, Chemical vapor deposition, Visualization, Distance measurement, RGB color model, Visual process modeling, Absorbance, Absorption, Eye models

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Proceedings Article | 5 May 2017 Presentation + Paper

HMD daylight symbology: color choice and luminance considerations

Thomas Harding, Jeffery Hovis, Michael Smolek, Leonard Temme, Morris Lattimore, Clarence Rash

Proceedings Volume 10197, 101970Q (2017) https://doi.org/10.1117/12.2261883

KEYWORDS: Color blindness, RGB color model, Information visualization, Standards development, Visual process modeling, Visual communications, Solids, Diamond, Head-mounted displays, Heads up displays, Color vision, Visualization, Situational awareness sensors, Manufacturing

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SPIE Journal Paper | 31 January 2017 Open Access

Daylight luminance requirements for full-color, see-through, helmet-mounted display systems

Thomas Harding, Clarence Rash

OE, Vol. 56, Issue 05, 051404, (January 2017) https://doi.org/10.1117/12.10.1117/1.OE.56.5.051404

KEYWORDS: Head-mounted displays, Image quality, Optical engineering, LCDs, Heads up displays, Image processing, Clouds, Visualization, Standards development, RGB color model

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Proceedings Article | 13 May 2016 Paper

Perceptual issues for color helmet-mounted displays: luminance and color contrast requirements

Thomas Harding, Clarence Rash, Morris Lattimore, Jonathan Statz, John Martin

Proceedings Volume 9839, 98390E (2016) https://doi.org/10.1117/12.2223035

KEYWORDS: Head-mounted displays, Visualization, Color vision, Computer programming, Human vision and color perception, Physiology, Standards development, LCDs, Image quality, Heads up displays, Clouds, Visibility, Analytical research

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Proceedings Article | 21 May 2015 Paper

The impact of human factors, crashworthiness and optical performance design requirements on helmet-mounted display development from the 1970s to the present

Thomas Harding, Clarence Rash, William McLean, John Martin

Proceedings Volume 9470, 94700U (2015) https://doi.org/10.1117/12.2176405

KEYWORDS: Head-mounted displays, Eye, Head, Curium, Optical design, Sensors, Neck, Visualization, CRTs, Optical components

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Proceedings Article | 9 June 2011 Paper

The reported incidence of man-machine interface issues in Army aviators using the Aviator's Night Vision System (ANVIS) in a combat theatre

Keith Hiatt, Clarence Rash

Proceedings Volume 8041, 80410K (2011) https://doi.org/10.1117/12.883288

KEYWORDS: Visualization, Head-mounted displays, Neck, Human-machine interfaces, Surgery, Interfaces, Safety, Eye, Goggles, Head

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Proceedings Article | 5 May 2010 Paper

Perceptual and cognitive effects on the use of helmet-mounted displays due to external operational factors

Thomas Harding, Clarence Rash, Gregory Lang

Proceedings Volume 7688, 76880C (2010) https://doi.org/10.1117/12.848931

KEYWORDS: Head-mounted displays, Head, Visualization, Cognition, Hypoxia, Oxygen, Light sources and illumination, Neck, Environmental sensing, Temperature metrology

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Proceedings Article | 5 May 2010 Paper

Cognitive considerations for helmet-mounted display design

Gregory Francis, Clarence Rash

Proceedings Volume 7688, 76880D (2010) https://doi.org/10.1117/12.848930

KEYWORDS: Head-mounted displays, Visualization, Cognition, Information visualization, Visibility, Analytical research, Data processing, Sensors, LCDs, Scanning tunneling microscopy

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Proceedings Article | 5 May 2010 Paper

Aviator's night vision system (ANVIS) in Operation Enduring Freedom (OEF): user acceptability survey

Keith Hiatt, Christopher Trollman, Clarence Rash

Proceedings Volume 7688, 76880G (2010) https://doi.org/10.1117/12.848928

KEYWORDS: Visualization, Head-mounted displays, Night vision, Safety, Eye, Motion estimation, Night vision systems, Surgery, Statistical analysis, Goggles

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Proceedings Article | 2 May 2009 Paper

Flight performance using a hyperstereo helmet-mounted display: post-flight debriefing questionnaire

Melvyn Kalich, Clarence Rash, Thomas Harding, Sion Jennings, Gregory Craig, Geoffrey Stuart

Proceedings Volume 7326, 732605 (2009) https://doi.org/10.1117/12.819500

KEYWORDS: Head-mounted displays, Distortion, Curium, Sensors, Visualization, Image sensors, Head, Control systems, Safety, Aircraft structures

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Proceedings Article | 2 May 2009 Paper

Flight performance using a hyperstereo helmet-mounted display: aircraft handling

Sion Jennings, Gregory Craig, Geoffrey Stuart, Melvyn Kalich, Clarence Rash, Thomas Harding

Proceedings Volume 7326, 732604 (2009) https://doi.org/10.1117/12.819496

KEYWORDS: Head-mounted displays, Night vision systems, Fourier transforms, Analytical research, Night vision goggles, Global Positioning System, Control systems, Error analysis, Head, Safety

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Proceedings Article | 2 May 2009 Paper

Flight performance using a hyperstereo helmet-mounted display: adaptation to hyperstereopsis

Geoffrey Stuart, Sion Jennings, Melvyn Kalich, Clarence Rash, Thomas Harding, Gregory Craig

Proceedings Volume 7326, 732606 (2009) https://doi.org/10.1117/12.820500

KEYWORDS: Visualization, Sensors, Night vision, Head-mounted displays, Eye, Visual system, Night vision systems, Night vision goggles, 3D modeling, Defense and security

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Proceedings Article | 1 May 2009 Paper

The effect of a monocular helmet-mounted display on aircrew health: a 10-year prospective cohort study of Apache AH MK 1 pilots: study midpoint update

Keith Hiatt, Clarence Rash, Raymond Watters, Mark Adams

Proceedings Volume 7326, 732602 (2009) https://doi.org/10.1117/12.818510

KEYWORDS: Eye, Visualization, Control systems, Head-mounted displays, Error analysis, Visual analytics, Spherical lenses, Statistical analysis, Analytical research, Night vision goggles

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Proceedings Article | 14 April 2008 Paper

Visual issues associated with the use of the integrated helmet and display sighting system (IHADSS) in the Apache helicopter: three decades in review

Keith Hiatt, Clarence Rash, Kevin Heinecke

Proceedings Volume 6955, 69550C (2008) https://doi.org/10.1117/12.774499

KEYWORDS: Visualization, Head-mounted displays, Eye, Sensors, Head, Forward looking infrared, Information visualization, Image sensors, Imaging systems, CRTs

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Proceedings Article | 14 April 2008 Paper

Visual perceptual issues of the integrated helmet and display sighting system (IHADSS): four expert perspectives

Clarence Rash, Kevin Heinecke, Gregory Francis, Keith Hiatt

Proceedings Volume 6955, 69550D (2008) https://doi.org/10.1117/12.769524

KEYWORDS: Eye, Visualization, Head-mounted displays, Forward looking infrared, Sensors, Surgery, Image resolution, Head, Visual system, Brain

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Proceedings Article | 14 April 2008 Paper

Perceptual design tradeoff considerations for viewing I2 and FLIR with current helmet-mounted displays

Melvyn Kalich, Thomas Harding, Clarence Rash

Proceedings Volume 6955, 69550F (2008) https://doi.org/10.1117/12.776759

KEYWORDS: Head-mounted displays, Forward looking infrared, Sensors, Distortion, Cameras, Eye, Image sensors, Visualization, Nose, LCDs

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Proceedings Article | 4 May 2007 Paper

The legibility of HMD symbology as a function of background local contrast

Thomas Harding, John Martin, Clarence Rash

Proceedings Volume 6557, 65570D (2007) https://doi.org/10.1117/12.719657

KEYWORDS: Head-mounted displays, Spatial frequencies, Clouds, Heads up displays, Eye, Modulation, Solids, Modeling, Photography, Optical filters

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Proceedings Article | 1 May 2007 Paper

A limited flight study for investigating hyperstereo vision

Melvyn Kalich, Clarence Rash, William McLean, John Ramiccio

Proceedings Volume 6557, 65570I (2007) https://doi.org/10.1117/12.717219

KEYWORDS: Head-mounted displays, Visualization, Night vision, Curium, Head, Safety, Distortion, Sensors, Eye, Prisms

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Proceedings Article | 1 May 2007 Paper

AH-64 monocular HMD visual assessment during urban combat in operation Iraqi freedom (OIF)

Clarence Rash, J. Kevin Heinecke, Keith Hiatt

Proceedings Volume 6557, 65570W (2007) https://doi.org/10.1117/12.716892

KEYWORDS: Visualization, Head-mounted displays, Eye, Forward looking infrared, Sensors, Image processing, Signal processing, Image sensors, Infrared imaging, Analytical research

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Proceedings Article | 18 May 2006 Paper

A unified taxonomic approach to the laboratory assessment of visionic devices

Alan Pinkus, Clarence Rash

Proceedings Volume 6224, 622406 (2006) https://doi.org/10.1117/12.658462

KEYWORDS: Head-mounted displays, Eye, Transmittance, Image intensifiers, Image transmission, Optical design, Sensors, Optical testing, Chromatic aberrations, Image resolution

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Proceedings Article | 18 May 2006 Paper

Performance effects of mounting a helmet-mounted display on the ANVIS mount of the HGU-56P helmet

Thomas Harding, John Martin, Clarence Rash

Proceedings Volume 6224, 622409 (2006) https://doi.org/10.1117/12.666894

KEYWORDS: Head-mounted displays, Eye, Optical filters, Night vision, Imaging systems, Light sources, Light, Optical coatings, Optical simulations, Data modeling

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Proceedings Article | 18 May 2006 Paper

Evaluation of microvision SD2500 scanning laser display

Thomas Harding, Clarence Rash, Scott Dennis

Proceedings Volume 6224, 62240R (2006) https://doi.org/10.1117/12.668908

KEYWORDS: Head-mounted displays, Cameras, Modulation transfer functions, Contrast transfer function, Photography, Modulation, Electronics, Monochromatic aberrations, Laser based displays, Prototyping

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Proceedings Article | 19 May 2005 Paper

Using a helmet-mounted display computer simulation model to evaluate the luminance requirements for symbology

Thomas Harding, John Martin, Clarence Rash

Proceedings Volume 5800, (2005) https://doi.org/10.1117/12.602123

KEYWORDS: Head-mounted displays, Heads up displays, Clouds, Spatial frequencies, Computer simulations, Image processing, Image analysis, Statistical analysis, Visualization, Eye

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Proceedings Article | 19 May 2005 Paper

AH-64 aviator impressions of IHADSS HMD flight in Operation Iraqi Freedom

Keith Hiatt, Clarence Rash

Proceedings Volume 5800, (2005) https://doi.org/10.1117/12.619112

KEYWORDS: Visualization, Head-mounted displays, Eye, Forward looking infrared, Sensors, Head, Surgery, Night vision systems, Analytical research, Optical tracking

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Proceedings Article | 8 September 2004 Paper

Partial-overlap biocular image misalignment tolerance

Melvyn Kalich, Lisa Lont, Corina van de Pol, Clarence Rash

Proceedings Volume 5442, (2004) https://doi.org/10.1117/12.542411

KEYWORDS: Visualization, Head-mounted displays, Control systems, Eye, Image restoration, Prisms, Image fusion, Diagnostics, Tolerancing, CRTs

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Proceedings Article | 8 September 2004 Paper

AH-64 IHADSS aviator vision experiences in Operation Iraqi Freedom

Keith Hiatt, Clarence Rash, Eric Harris, William McGilberry

Proceedings Volume 5442, (2004) https://doi.org/10.1117/12.541385

KEYWORDS: Visualization, Eye, Head-mounted displays, Forward looking infrared, Telescopes, Geography, Surgery, Analytical research, Sensors, Internet

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Proceedings Article | 8 September 2004 Paper

Laboratory system for the evaluation of helmet-mounted displays

Howard Beasley, Thomas Harding, John Martin, Clarence Rash

Proceedings Volume 5442, (2004) https://doi.org/10.1117/12.543375

KEYWORDS: Head-mounted displays, Measurement devices, Cameras, Photography, Optical alignment, Iris, Analog electronics, Calibration, Image quality, Amplifiers

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Proceedings Article | 8 September 2004 Paper

Potential see-through performance deficits in U.S. Army developmental helmet-mounted displays

Thomas Harding, Clarence Rash

Proceedings Volume 5442, (2004) https://doi.org/10.1117/12.543308

KEYWORDS: Head-mounted displays, Visualization, Spatial frequencies, Modulation transfer functions, LCDs, Flat panel displays, CRTs, Modulation, Optical filters, Target detection

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Proceedings Article | 8 September 2003 Paper

The role of the pilot's night vision system (PNVS) and the integrated helmet and display sighting system (IHADSS) in AH-64 Apache accidents

Jessica Stelle, Barbara Reynolds, Clarence Rash, R. David Peterson, Patricia Leduc

Proceedings Volume 5079, (2003) https://doi.org/10.1117/12.485870

KEYWORDS: Head-mounted displays, Visualization, Forward looking infrared, Sensors, Night vision systems, Safety, Eye, Failure analysis, Infrared sensors, Databases

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Proceedings Article | 8 September 2003 Paper

Proof of principle for helmet-mounted display image quality tester

Sheng-Jen Hsieh, Thomas Harding, Clarence Rash, Howard Beasley, John Martin

Proceedings Volume 5079, (2003) https://doi.org/10.1117/12.485548

KEYWORDS: Cameras, Head-mounted displays, Image analysis, Prototyping, Inspection, Image quality, Human-machine interfaces, Image acquisition, Algorithm development, Image processing

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Helmet mounted displays (HMDs) provide essential pilotage and fire control imagery information for pilots. To maintain system integrity and readiness, there is a need to develop an image quality-testing tool for HMDs. There is currently no such tool. A framework for development of an image quality tester for the Integrated Helmet and Display Sighting System (IHADSS) used in the U.S. Army's AH-64 was proposed in Hsieh et al. This paper presents the prototype development, summarizes the bench test findings using three IHADSS helmet display units (HDUs), and concludes with recommendations for future directions. The prototype consists of hardware (two cameras, sensors, image capture/data acquisition cards, battery pack, HDU holder, moveable rack and handle, and computer) and software algorithms for image capture and analysis. Two cameras with different apertures were mounted in parallel on a rack facing the HDU holder. A handle was designed to allow users to position the HDU in front of the two cameras. The HMD test pattern was then captured. Sensors are used to detect the position of the holder and whether the HDU was angled correctly in relation to the camera. Two sets of unified algorithms were designed to detect features presented by the two cameras. These features include focus, orientation, displacement, field-of-view, and number of gray-shades. Images of test pattern were captured and analyzed, and used to develop a specification for each inspection feature. Experiments were conducted to verify the robustness of the algorithms. A worst-case scenario for factors such as clock-wise and counterclockwise tilt, degree of focus, magnitude of brightness and contrast, and shifted images were set up and evaluated. Bench testing of three field-quality HDUs indicate that the image analysis algorithms are robust and able to detect the desired image features. Suggested future work includes development of a learning algorithm to automatically develop or revise feature specifications as the number of inspection samples increases.

Proceedings Article | 8 September 2003 Paper

Survey results for integrated helmet and display sighting system fitting issues

Keith Hiatt, Clarence Rash, Malcolm Braithwaite, Melissa Isaak, Jessica Stelle, Mark Adams

Proceedings Volume 5079, (2003) https://doi.org/10.1117/12.489019

KEYWORDS: Eyeglasses, Head-mounted displays, Ear, Glasses, Visualization, Contact lenses, Interfaces, Neck, Foam, Optical alignment

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Proceedings Article | 8 September 2003 Paper

Biocular image misalignment tolerance

Melvyn Kalich, Clarence Rash, Corina van de Pol, Terri Rowe, Lisa Lont, R. David Peterson

Proceedings Volume 5079, (2003) https://doi.org/10.1117/12.485926

KEYWORDS: Tolerancing, Head-mounted displays, Visualization, Eye, Telescopes, Mirrors, Gold, Prisms, Reticles, Image fusion

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Proceedings Article | 8 September 2003 Paper

Roll head motion in rotary-wing flight with helmet-mounted displays

Jessica Stelle, Clarence Rash, Ryan Rostad

Proceedings Volume 5079, (2003) https://doi.org/10.1117/12.485874

KEYWORDS: Head, Visualization, Head-mounted displays, Visual analytics, Thermography, Motion analysis, Analytical research, Statistical analysis, Databases, Night vision goggles

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