Introduction

The availability in 2021, on the consumer market of standalone (un-tethered) Head Mounted Displays (HMDs) for Virtual Reality (VR) and Augmented Reality (AR) is an enabling technology in the field of cognitive psychology of the human visual system. It is of special interest in forensic sciences where one need to reconstruct the characteristics of observed phenomena from on a witness testimony.

Such HMDs allow for much easier measurement of some characteristics of the human visual systems. Some issues existing in more basic methods are circumvented, new issues arise.

This article tries to list the already known issues ; the new issues raised and which parameters are now measurable.

We are here specifically interested in the estimation of

angular size

angular height

apparent luminosity / brightness

angular speed

color

distance

size

estimation of the evolution of all the parameters over time

We already know that some parameters are very often highly mis estimated by witnesses. This includes the angular height, angular size, angular speeds, durations. These problems are known for over a century ¹⁾, yet, we feel that there is currently a huge lack of characterization of the biaises in the reports.

Some tentative studies were done, but with a lack of control and strict definition of the setup ²⁾.

As soon as an optical system or a non natural method there is a risk of altering the response in a non detected way.

For instance,

alteration by the looking though an eye piece
alteration by looking through a window, depending on the distance to the window
alteration by the use of an object held by hand for comparison.
alteration by being sitting or standing.
alteration by the emotions felt.
alteration by the visual context around the object observed
alteration by the location of the witness : inside, outside of a building. 

This can alter the estimations of

angular size
angular height
luminosity
angular speed

New interesting developement : being able to obtain error bars as a function of the witness estimations.

the literature shows some interests for therapeutic use military applications are concentrated on the

google “augmented reality” “cognitive psychology” forensic