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RESEARCH PAPER
Investigating the impact of laser dazzling on
shooting performance in a simulator environment:
baseline scene
Tomas Földes ,a,*Helena Rico Pereira ,b,c Sebastian Stutz,d
Michael Henrichsen ,dHugo Alexandre Ferreira ,band Marijke Vandewal a
aRoyal Military Academy, CISS Department, Brussels, Belgium
bUniversity of Lisbon, Institute of Biophysics and Biomedical Engineering, Faculty of Sciences, Lisboa, Portugal
cNOVA School of Science and Technology and CTS/UNINOVA, Caparica, Portugal
dFraunhofer-Institut für Optronik, Systemtechnik und Bildauswertung, Ettlingen, Germany
ABSTRACT. Our study examines how laser dazzling affects human performance, specifically
accuracy and reaction times, using a laser dazzling shooting simulator at the
Royal Military Academy, Belgium. The research assesses the performance degra-
dation under laser dazzling in a simple, baseline scene, including different target
contrasts and the use of laser eye protection. Utilizing a 532 nm green laser for
a safe yet effective dazzle, trained shooters’performances were measured and ana-
lyzed. The results align strongly with a live shooting trial and correlate with Adrian/
CIE visibility levels. Additionally, electrical brain activity data, acquired via electro-
encephalography (EEG), provided insights into the shooters’mental states. EEG-
derived metrics, particularly frontal alpha asymmetry and frontal alpha power,
revealed that participants experienced heightened negative and avoidance emo-
tions, coupled with increased cognitive load prior to shooting. These responses
returned to baseline levels postshooting. Moreover, distinct cognitive and emotional
states were observed in relation to different types of laser eye protection goggles,
potentially correlating with variations in shooting performance. These findings pave
the way for future research with more advanced simulation scenes and deepen
understanding of the effects of laser dazzle.
© The Authors. Published by SPIE under a Creative Commons Attribution 4.0 International License.
Distribution or reproduction of this work in whole or in part requires full attribution of the original
publication, including its DOI. [DOI: 10.1117/1.OE.63.3.034101]
Keywords: laser dazzling; shooting simulator; human performance; cognitive and
emotional state; electroencephalography
Paper 20230988G received Oct. 16, 2023; revised Feb. 14, 2024; accepted Feb. 16, 2024; published Mar.
12, 2024.
1 Introduction
Laser dazzling, the technique of using visible light lasers to interfere with human vision or
degrade optical sensor operations, has gained increasing relevance in military, law enforcement,
and aviation sectors. As a nonlethal countermeasure, understanding how laser dazzle affects
human performance is of particular interest. Although there are several models and simulations
that evaluate the impact of laser dazzle on the human eye,1–7few studies have examined its effects
on human task performance.8–13 This paper aims to provide insights into this subject, presenting
findings from laser dazzling trials conducted using a shooting simulator.
As part of the NATO SET-249 task group,14 we conducted two measurement campaigns at
the Royal Military Academy in Brussels in 2021 and 2022. These trials, serving as baseline
*Address all correspondence to Tomas Földes, tomas.foldes@mil.be
Optical Engineering 034101-1 March 2024 •Vol. 63(3)
explorations in a simulator environment, aimed to investigate the shooting performance of
trained shooters when dazzled by green laser light at 532 nm. The 2021 trials were designed
to approximate a live shooting range trial13 with the purpose of validating our shooting
simulator’s results.
The 2022 trials expanded the scope, exploring various parameters like target contrasts and
ballistic goggles, and introduced electrical brain activity data analysis via the electroencepha-
lography (EEG) technique to assess the mental state of shooters, marking a novel aspect of this
study.
Herein, “mental state”refers particularly to cognitive and emotional distress, which influ-
ence mental workload—defined as the mental cost incurred while performing a specific task.
This workload is dependent on factors like task difficulty, individual skills, and perception.15,16
Such distress, manifesting as anxiety or worry, can negatively impact performance17,18 by reduc-
ing the processing and storage capacity of working memory, thereby increasing on-task effort.19
Due to its high temporal resolution, EEG has shown potential in detecting these mental states,
with alpha power activity being used as a marker for stressful situations.20
This approach, including comparisons with live shooting data and visibility level (VL) cal-
culations, lays the baseline for future advancements of the simulator. Building on these results,
we aim to progress toward more realistic scenes in the future. This will involve gradually incor-
porating more complex elements, such as target recognition, identification, tracking, and realistic
backgrounds enhancing the applicability of results from simulator trials.
2 Methodology
2.1 Shooting Simulator
Our shooting simulator21,22 featured a dark tunnel closed off at one end by a projection screen, a
projector (Epson EH-TW9400W), a modified airsoft rifle equipped with an invisible infrared
(IR) laser, an IR spot tracking camera, and a dazzling laser (see Fig. 1). The projector was used
in its default configuration, with the color mode set to “natural,”except for specific segments of
the 2022 trials. For those, termed “DARK”settings in the 2022 trials (explained in the 2022
scenario description in Sec. 2.3), the projector’s brightness and iris were set to their minimum
levels to achieve the low-luminance levels as reported in Table 1.
For the dazzling of shooters, a modified GLARE MOUT Plus laser dazzler (200 mW,
532 nm, 6 mrad divergence, B. E. Meyers) was used, with its divergence increased to 150 mrad
by attaching a lens. This resulted in a spot diameter of 0.5 m at the shooter’s head position,
resulting in a laser irradiance between 90 and 110 μW∕cm2. The projected, simple, baseline
scene simulated Olympic type bullseye targets at a distance of 25 m, with various contrast set-
tings on a simple, gray background. The simulator software, developed within the unity game-
engine platform, performed various functions including scene generation, laser spot tracking, and
data storage.
An eye-safe 850 nm laser pointer (CPS850V, Thorlabs) was mounted on an M4A1 MWS
assault rifle replica (Tokyo Marui) equipped with an iron sight. The laser spot on the projection
screen was tracked by a camera (MAKO G-158B, Allied Vision equipped with a bandpass filter
in front of the optics, centered around 850 nm), and the position and timing of the spot were
registered into a database at every trigger event. Trigger events were generated by the depression
of a momentary switch located beneath the weapon trigger, causing the target to disappear from
the screen. No additional feedback was given to the shooters during these trials. An ESP32-based
board fixed to the weapon managed laser operation, trigger and Wi-Fi communication with
UNITY.
The target projection simulated 1-m diameter Olympic type bullseye targets at a distance of
25 m, comprising either concentric circles for the 25% and 0.5% target contrast settings, or con-
centric circles within a white square for the 100% target contrast setting, as shown in Fig. 2. The
contrast settings of 100%, 25%, and 0.5% in the simulator correspond to opacity levels set in the
unity game-engine, influencing how the gray background appeared through the black and white
parts of the target. Consequently, these settings affected the overall perceived contrast. The actual
contrast values, as experienced by the participants, are more accurately represented by the Weber
contrast measurements provided in Table 1.
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Optical Engineering 034101-2 March 2024 •Vol. 63(3)
Fig. 1 Scheme of the shooting simulator: 1, dazzling laser; 2, shooter with modified gun; 3, beam
from dazzling laser; 4, projected target; 5, dazzling angle; and 6, camera tracking the infrared spot
of the weapon.
Table 1 Measured luminance levels of the different projected targets and calculated Weber con-
trast of the black target center with the white outer rings of the targets as well as the white outer
rings of the target with the gray background. The terms “BRIGHT”and “DARK”are explained in the
2022 scenario description in Sec. 2.3.
Target
contrast
setting (%)
Black
(target)
(cd∕m2)
White
(target)
(cd∕m2)
Gray
(background)
(cd∕m2)
Weber contrast
Black center
with white outer
of the target (%)
White outer
of the target with
gray background
BRIGHT 2022 100 5.1 119 27.7 −95.7 329.6
25 12.36 59 27.7 −79.1 113.0
0.5 27.25 28.28 27.7 −3.6 2.1
DARK 2022 0.5 0.543 0.58 0.557 −6.4 4.1
BRIGHT 2021 100 5 140 30 −96.4 366.7
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2.2 Electroencephalography–Photoplethysmography Headband
During this trial, a sensorized headband was worn by the majority of the shooters (limited by
logistical considerations). The sensorized headband was in-house developed, based on the
physiological signal acquisition platform BITalino.23 It was comprised of a textile-based head-
band enclosure with dry metal electrodes that record the electrical brain activity via EEG in the
left and right forehead (positions Fp1 and Fp2 in the 10/20 EEG electrode placement system,
respectively). Additionally, the headband included an optical sensor that was placed on the left
earlobe to record the blood-volume pulse [photoplethysmography (PPG)] signals. The collected
EEG data were used to assess the shooters’mental (cognitive and emotional) state immediately
before each shot, as well as 2 and 4 s after the shot.
2.3 Participants
The participants were Belgian military members with similar and adequate shooting experience.
Prior to the trial, they were briefed on laser safety aspects, test protocol, and provided with an
experimental protocol and consent form. None of the participants had experienced laser dazzle
before these experiments, with the only exception being those who had participated in the 2021
trial and returned for the 2022 trials. The tests were approved by the Academic Ethical
Committee Brussels Alliance for Research and Higher Education (Dossier Number B200-
2021-098).
2.4 Test Protocol and Scenarios
The participants were given the following instructions as they entered the shooting tunnel one
by one.
(1) Assume the standing shooting position above a cross marked on the floor, aim at the
projection screen, and close your eyes to allow for the adjustment of the laser dazzler
pointing direction.
(2) Take three zeroing shots without dazzling at ease at a white dot in the middle of the
screen.
(3) Adopt a nonconventional resting position, which involved releasing the rifle with the
nonfiring hand, leaning forward, looking at the floor, and resting the muzzle of the rifle
on the cardboard box on the ground.
(4) Upon hearing a “BEEP”signal, quickly assume the standing shooting position, aim at the
target, pull the trigger, yell “shot,”and return to the nonconventional resting position.
(5) Wait for the next BEEP signal.
Additionally, participants were advised not to look directly at the laser to avoid any potential
degradation in shooting performance due to the aftereffects of laser dazzle. Although not spe-
cifically monitored, direct gazing at the laser by the shooters during the trials was not anticipated,
given the instructions and the task’s focus. Following each trial, participants were informally
asked if they noticed any aftereffects, anything unusual, or any discomfort. They reported not
having noticed any aftereffects. No formal postparticipation interviews were conducted.
During the 2021 campaign trials, the BEEP signal was repeated every 10 s, which was deter-
mined on the bases of a preliminary trial, to allow the shooters ample time to take the shot without
unnecessarily prolonging the trial. In the 2022 campaign trials, the next BEEP signal followed
10 s after the previous shot was registered (within a set).
Shooters were exposed to the laser only while aiming and taking their shots. Upon hearing
the BEEP signal, they quickly assumed the shooting position, aimed, fired, and then returned to
looking at the ground, thereby minimizing their exposure to the laser. This process meant that the
actual exposure duration to the laser was slightly shorter than the reported shooting delay values,
as these included the time taken to assume the shooting position. Although the laser was activated
1 s before each BEEP signal, the shooters were still looking at the floor in the nonconventional
resting position and they were not actively exposed to the laser. Additionally, the laser was turned
off after each shot was taken and remained off until 1 s before the next BEEP signal.
To prevent muscle memory effects, the targets were presented in quasirandom horizontal
positions, and the nonconventional resting position (release the rifle with the nonfiring hand,
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Optical Engineering 034101-4 March 2024 •Vol. 63(3)
lean forward, look at the floor, and rest the nozzle of the rifle on the cardboard box on the ground)
was enforced between shots.
In the 2021 campaign trials, participants were tasked with completing two sets of a shooting
sequence while wearing either standard ballistic goggles (LEP0) or prescription glasses. The two
sets comprised 8 and 7 shots, respectively, with a 100% contrast target appearing in the various
quasirandom horizontal positions (as shown in Fig. 2) against a bright gray background. The first
two shots in the first set and the first shot in the second set were taken without laser dazzling,
whereas the remaining shots were taken with the target appearing at dazzling angles of 17 deg,
11 deg, 8 deg, and 6 deg. Collectively, this resulted in three shots without dazzling and three shots
at each dazzling angle. The quasirandom angular positions of the target relative to the dazzling
laser for both sets are detailed in Table 2.
In the 2022 campaign trials, participants undertook four shooting sequence sets, featuring
different ballistic goggles. Notably, the first set involved alternating among three goggle types—
LEP0 (standard transparent goggles without laser protection), LEPX, and LEPY (both providing
532 nm laser protection but with LEPY having a lighter tint than LEPX) in a random order.
During this set, participants executed three shots per goggle type, targeting a 0.5% low-contrast
target. The targets were positioned in quasirandom horizontal locations against a “DARK”
low-luminance backdrop. This setup did not involve any laser dazzling, focusing instead on par-
ticipants’ability to perceive and aim at the less visible targets.
The subsequent three sets (each with a different pair of goggles) consisted of five shots each,
with targets appearing at different contrast levels and quasirandom horizontal positions on a
brighter background (referred to as “BRIGHT”). The quasirandom contrast and angular positions
of the targets relative to the dazzling laser for these three sets are presented in Table 3. The aim
Table 2 Dazzling angles of the projected targets in chronological order during the 2021 campaign
trials. The high-contrast target projection was used for all shots.
Order of
shots 1 2 3 4 5678
First
set
No laser
100%
No laser
100%
Laser on
17 deg
100%
Laser on
8 deg
100%
Laser on
17 deg
100%
Laser on
6 deg
100%
Laser on
11 deg
100%
Laser on
8 deg
100%
Second
set
No laser
100%
Laser on
11 deg
100%
Laser on
6 deg
100%
Laser on
17 deg
100%
Laser on
11 deg
100%
Laser on
8 deg
100%
Laser on
6 deg
100%
Fig. 2 Photo of (a) the 25% contrast target and (b) the 100% contrast target. The 0.5% contrast
target (not shown) had the same shape as the 25% contrast target.
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Optical Engineering 034101-5 March 2024 •Vol. 63(3)
with these sets was to compare the performance with 25% contrast targets under LEP0 against the
100% contrast targets from the 2021 trials and to observe the variations in performance between
different LEPs across various target VLs at given dazzling angles.
To aid in the preparation for the main 2022 campaign trials, a preliminary trial involving
only four shooters was conducted. Each shooter completed two sets of a shooting sequence: one
set while wearing LEP0 goggles and a second set while wearing LEPX goggles. The quasiran-
dom contrast and angular positions of the targets relative to the dazzling laser for these sets are
provided in Table 4. Although these measurements were excluded from the primary statistical
analysis of shooting scores and delays to maintain a balanced dataset between LEPX and LEPY
conditions, they contributed valuable data for the limited mental state statistical analysis dataset.
During a NATO SET-249 meeting held in Brussels, an additional measurement trial was
conducted with four shooters. The primary objective was to present the main 2022 campaign
scenarios to the group members. Although this measurement set replicated the conditions of
the main campaign trials, its data were not included in the main statistical analysis of shooting
scores and delays, in order to maintain a focused assessment. However, it played a crucial role in
the mental state statistical analysis, contributing to the augmentation of our limited dataset in that
aspect. It is important to acknowledge that the shooters were aware of being observed via camera
feed during this trial, potentially introducing a performance bias. Despite this potential influence,
the data collected remained valuable and relevant for the mental state statistical analysis.
2.5 Participants and Data Collection
In the 2021 campaign trials, 30 participants joined, including 7 left-handed and 23 right-handed
shooters, resulting in 428 recorded shots out of a potential 450. Exclusions comprised five par-
ticipants without ballistic goggles for the primary score and delay analysis. Instances impacting
the analysis included four unattempted shots due to the dazzle. For these, zero scores were
assigned, and the shooting delays were recorded as missing values in the statistical analysis.
Two shots following the unattempted shots were not correctly registered due to our lack of pre-
paredness for this eventuality, and both the score and delay values were discarded in the statistical
analysis. Subsequent shooters were instructed to “shoot into the ground”when unable to take a
shot, verbally inform the staff, and return to a nonconventional resting position. There was one
Table 3 Dazzling angles and contrast levels of the projected targets during the 2022 trials for the
BRIGHT condition, presented in chronological order for each set of goggles.
Order of shots 1 2 3 4 5
LEP0 set No laser
0.5%
Laser on
17 deg 25%
Laser on
8 deg 25%
Laser on
11 deg 25%
Laser on
6 deg 25%
LEPX set No laser
0.5%
Laser on
6 deg 25%
Laser on
17 deg 100%
Laser on
11 deg 25%
Laser on
6 deg 0.5%
LEPY set No laser
0.5%
Laser on
17 deg 100%
Laser on
6 deg 0.5%
Laser on
11 deg 25%
Laser on
6 deg 25%
Table 4 Dazzling angles and contrast levels of the projected targets during the preliminary 2022
trial, presented in chronological order for each set of goggles.
Order of
shots 1 2 3 4 5 6 7 8 9 10
LEP0 set No laser
11 deg
25%
No laser
6 deg
100%
Laser on
17 deg
25%
Laser on
8 deg
100%
Laser on
11 deg
100%
Laser on
6 deg
25%
Laser on
11 deg
25%
Laser on
6 deg
100%
Laser on
8 deg
25%
Laser on
17 deg
100%
LEPX set No laser
17 deg
25%
No laser
8 deg
25%
Laser on
11 deg
25%
Laser on
6 deg
100%
Laser on
17 deg
100%
Laser on
8 deg
25%
Laser on
11 deg
100%
Laser on
6 deg
25%
Laser on
17 deg
25%
Laser on
6 deg
100%
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misfire due to hardware issues. An outlier shooter with extended response times was excluded.
Additionally, five participants with prescription glasses were treated statistically as goggle wear-
ers due to performance equivalence.
In the 2022 campaign trials, there were 19 participants, 9 of whom did not participate in the
2021 campaign trials. All shooters wore the provided ballistic goggles, and those requiring pre-
scription corrections wore contact lenses underneath the goggles. Two of the 19 participants were
left-handed, a subset of the 7 left-handed shooters from 2021. There was one instance of an
unattempted shot due to the dazzle, resulting in a zero score and missing value for the shooting
delay in the statistical analysis. There was also one instance where the gun did not register the
trigger action and one instance of a software glitch, which left out one target position. Excluding
the first shots with each pair of goggles in the DARK shooting set, which were considered as
“training”shots, there were 397 correctly registered scores and 396 correctly registered shooting
delay values.
For logistical reasons, sensorized headband EEG data were recorded for only 14 out of the
19 participants in the 2022 main trial. To augment this restricted dataset, we incorporated data
from the preliminary 2022 trial (four shooters, with three also participating in the main 2022 trial)
and the NATO group meeting showcase trial (four distinct shooters, with three also involved in
the 2022 trial) into the statistical analysis. There were some instances of recorded data being
noisy due to suboptimal headband fitting on the shooters. Overall, we were able to include a
total of 675 observations in the statistical analysis. These observations were relatively evenly
distributed among data points representing the mental state conditions just before the shot,
2 s after the shot, and 4 s after the shot.
2.6 Mental State Analysis Indicators
In the current paper, we focused on two indicators computed from the recorded EEG data, rep-
resentative of the cognitive and emotional state of the shooter: frontal alpha power and the frontal
asymmetry index. To obtain these indicators, we computed the arithmetic mean power spectral
density of each EEG channel (Fp2 and Fp1) for the alpha frequency band (8 to 12 Hz) using the
Welch’s method (Hamming window of 8 segments of the length signal with 50% overlap, and
256 points), via an in-house developed signal processing script.24 The power spectrum was com-
puted individually for the three time intervals: 2 s just before the shot, 2 s after the shot, and 4 s
after the shot.
The frontal asymmetry index measures the difference in the alpha power between the left and
right frontal regions, and is computed as
EQ-TARGET;temp:intralink-;e001;117;328frontal asymmetry index ¼alpha power Fp2 −alpha power Fp1 (1)
with Fp1 and Fp2, corresponding to electrode positions in the left and right hemisphere,
respectively.
Frontal asymmetry has been associated with emotional valence (positive versus negative)
and motivation (attractive versus avoidance).25 Previous studies found that decreased left alpha
power is related to positive valence or an approach-oriented behavior, whereas decreased right
alpha power is related to negative valence or avoidance.26,27 Consequently, a more positive frontal
asymmetry index has been associated with more emotional control, whereas a more negative
frontal asymmetry index suggests a lack of emotional control. These relationships were already
observed in a shooting task, performed under pressure, which resulted in a more negative asym-
metry index and decreased shooting accuracy compared to the nonstressed condition.28
Additionally, the frontal alpha power was also computed as
EQ-TARGET;temp:intralink-;e002;117;173frontal alpha power ¼alpha power Fp2 þalpha power Fp1:(2)
The frontal alpha power has been associated to cognitive load, showing higher values in a
more demanding task than in a low demanding task (mental arithmetic).29,30
Herein, the alpha power values were normalized to the mean of “baseline”values acquired
during the 2 s before the BEEP sound signals instructing the shoots. In this manner, mental state
changes due to the subsequent shooting tasks could be more accurately assessed.
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2.7 Statistical Analysis
For the statistical analysis of shooting scores and delays, we combined data from the 2021 trial
and the 2022 BRIGHT conditions sets, since they involved similar shooting tasks and shared
some participants. We analyzed the 2022 DARK dataset separately. For this primary analysis, we
excluded the first shots from each set, which were intended as training shots, as well as data from
the five participants who completed the trials without ballistic goggles or prescription glasses in
the 2021 trials. The remaining data were analyzed using a linear mixed model also accounting for
repeated measures, which included the score and delay of each shot. We encoded these measures
using the dazzling angle, target contrast, the protection goggles used, trial identification, and the
number of repeated shots under the same conditions in a given trial by a shooter. To address the
correlation between repeated measures, we used a first-order autoregressive structure with het-
erogenous variances. We found that variances of shooting scores and delays were significantly
larger for difficult shots (e.g., those at a 6 deg dazzling angle) compared to easy shots (e.g., those
at a 17 deg dazzling angle). We also observed a strong correlation between results at nearby
angles, which decreased as angles became more distant, which justified using the autoregressive
structure. The fixed effect of the model included the interaction of dazzling angle, target contrast,
worn goggles, and trial identification. Dazzling angles and contrast values were treated as ordinal
variables, whereas worn goggles and trial identification were treated as nominal variables. We
also tested including the interaction of the repeated variable as a parameter in the fixed effect, but
it had no effect on the estimated marginal means produced by the model. To account for indi-
vidual differences in shooting ability, we treated each shooter as a subject in the model, with a
random specific intercept included.
For the 2022 DARK dataset analysis, we followed a similar approach to that used for the
2021 trial and 2022 BRIGHT conditions data. The first shot from each set, intended as a training
shot, was excluded from this analysis. We encoded the repeated measures of shooting scores and
delays based on the protection goggles used and the number of times a shot was repeated under
the same conditions by a shooter in a given trial.
Initially, we considered a first-order autoregressive structure to address the correlation
between repeated measures, as in the case of the 2021 and 2022 BRIGHT dataset. However,
our analysis indicated that a scaled-identity structure was sufficient. In our model, the fixed effect
was the type of protection goggles used. We also tested including the interaction between goggles
and repeated shots, but this was not significant for either shooting scores or delays.
As with our previous analyses, individual shooters were included as subjects in the model,
with a random intercept to account for variations in shooting ability.
For the statistical analysis of the frontal asymmetry index and frontal alpha power indicators,
we combined data from the main 2022 BRIGHT condition trials, the 2022 preliminary trials, and
the 2022 NATO meeting showcase trial. Similar to the shooting score and delay statistical analy-
sis, we excluded data from the first shots in each set, which were considered training shots. The
remaining data were subjected to a linear mixed model. This model encompassed frontal asym-
metry index and frontal alpha power values for each shot at three measurement moments: just
before the shot; 2 s after the shot; and 4 s after the shot. These measures were encoded based on
dazzling angle, target contrast, protective goggles used, and the measurement moment.
Consistently with the shooting score and delay analysis, a first-order autoregressive structure
with heterogeneous variances was employed. The fixed effect of the model involved the inter-
action of dazzling angle, target contrast, worn goggles, and the measurement moment. Dazzling
angles and contrast values were treated as ordinal variables, while worn goggles and the meas-
urement moment were considered nominal variables. Each shooter was treated as a subject in the
model. However, due to convergence issues, a random specific intercept for each subject could
not be included. Consequently, this limitation may have contributed to larger error bars and the
possibility of some false negatives.
3 Results and Discussion
3.1 Shooting Scores and Delays
Figure 3depicts a subset of calculated estimated marginal means values across the various levels
of the fixed variables, from the 2021 and main 2022 trials (under BRIGHT settings). The shown
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Optical Engineering 034101-8 March 2024 •Vol. 63(3)
error bars correspond to the 95% confidence intervals of these estimated marginal means, directly
informing on the statistical significance of differences.
Analysis of the LEP0 (transparent ballistic goggle) 100% target contrast data reveals that
shooting scores are significantly lower at the 6-deg dazzling angle compared to the “no laser
dazzle,”17-deg, and 11-deg dazzling angles. Shooting scores appear to remain statistically
equivalent at the 11-deg and larger dazzling angles. Although the differences are statistically
insignificant, the highest shooting scores were obtained at the 17-deg dazzling angle, rather than
at the expected no laser dazzle level. Notably, shooting scores at the 17-deg dazzling angle are
significantly higher than those at the 8-deg and 6-deg dazzling angles. Furthermore, the analysis
of the 100% target contrast delays shows that there were no statistically significant differences in
shooting delays across different dazzling angles.
Regarding the LEP0 25% target contrast data, shooting scores are significantly lower at the
6-deg dazzling angle compared to the 17-deg and 11-deg dazzling angles. Inspection of the 25%
target contrast delays reveals that while they are not significantly different at the 95% confidence
level at the different dazzling angles (mainly because of the large variance at small dazzling
angles), they are systematically longer at smaller dazzling angles.
When comparing the estimated marginal means of the LEP0 ballistic goggle 25% target
contrast shots with those of 100% target contrast shots, we consistently observe higher scores
for the 25% target contrast, although without reaching statistical significance. Conversely, shoot-
ing delays consistently increase for the 25% target contrast and show statistically significant rises
at the more challenging dazzling angles (6-deg and 8-deg dazzling angles).
Importantly, the 25% target contrast data were collected during the 2022 trials, whereas the
100% target contrast data were gathered in the 2021 trials. In the 2022 trials, the initial shots in
each set featured demanding 0.5% contrast targets. In contrast, the 2021 trials began with easily
visible 100% contrast targets, without laser dazzling. Additionally, the 2022 trial introduced a
first set featuring low-background luminance and low-target contrast (DARK). One could specu-
late that the heightened demands of the initial targets in the 2022 trial may have driven shooters to
adopt a slower and more careful and accurate shooting approach, however, the shots taken while
wearing LEPX or LEPY were taken just as quickly (within error bars) as the shots during the
2021 campaign trials. More likely, the similar trend in scores for both target opacities across
Fig. 3 Subset of the estimated marginal means of (a) scores and (b) delays from the 2021 and
main 2022 campaigns as estimated by the linear mixed model. Error bars stand for 95% confi-
dence intervals. Codes shown in the legend represent the contrast of the target followed by the
designation of the worn goggles. The curves are slightly offset on the x-axis for visual clarity.
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dazzling angles might indicate a deliberate speed-accuracy trade-off31 mainly driven by the
degree of laser dazzle, rather than the visibility of the target.
Further analysis of the estimated marginal means of scores and delays for the 25% target
contrast shots taken while wearing LEPX or LEPY ballistic goggles with laser eye protection,
reveals that both effectively mitigate the impact of laser dazzling within the studied range of
conditions. Noticeably, elevated scores and shooting delays as short (within error bars) as the
shortest ones achieved with the LEP0 transparent goggles for 100% contrast targets are achieved.
The performance with LEPX and LEPY remains statistically indistinguishable at both the 11-deg
and 6-deg dazzling angles for the 25% contrast target shots.
3.2 Emotional/Mental State Indicators
Figure 4shows the time courses of the frontal asymmetry index and the frontal alpha power for
two different participants wearing the three types of goggles (LEP0, LEPX, and LEPY) during
the shooting task at the 11-deg dazzling angle and 25% contrast target.
The frontal alpha asymmetry is typically more negative for LEP0 than for LEPX and LEPY
before the shot, then trending to zero and then increasingly negative from 2 to 4 s. On the other
hand, after the shot, the frontal alpha asymmetry for LEPX and LEPY trends to zero (i.e., it trends
to the baseline levels at 2 s before the “BEEP”sound signal). The frontal alpha power is higher
for LEPX than for the other two goggles, while the LEPY goggles show values closer to zero (or
baseline levels). For the LEP0 and LEPX goggles, there is a trend in the frontal alpha power:
power goes up before the shot and gradually decreases, which may be related to the mental state
change from preparation to resolution of the task. Overall, this figure illustrates how dynamic the
shooting task is.
In the context of the BRIGHT dataset, Fig. 5illustrates the estimated marginal means of
frontal asymmetry index and frontal alpha power, collapsed across the various dazzling angles,
target contrasts, and worn ballistic goggles, at the three different measurement moments, and for
all participants. Notably, the most negative frontal asymmetry index and the highest frontal alpha
power values are observed just before the shot, i.e., 2 s before the shot (a time window that
translates the immediate preparation of the shot). Following the shot, a distinct declining trend
is evident for both indicators, with frontal asymmetry becoming significantly less negative and
frontal alpha power significantly reduced by 4 s after the shots, approaching the baseline values.
Overall, results suggest that before the shot, participants had a more negative emotional valence
or sense of avoidance toward the task, as well as a higher cognitive load, than after the shot,
probably resulting from the anticipation of addressing a demanding task. These results seem
Fig. 4 Exemplar frontal alpha asymmetry and frontal alpha power time courses during the shooting
task at 11-deg dazzling angle and 25% target contrast, for two different participants and the three
types of goggles (LEP0, LEPX, and LEPY). The time courses cover the three measurement
moments: before the shot (−2 to 0 s) and 0 to 2 s and 2 to 4 s after the shot.
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to agree with the literature in which more demanding tasks are associated with more a negative
frontal asymmetry index and higher frontal alpha power.
Figure 6illustrates the estimated marginal means at the 11-deg dazzling angle and 25%
target contrast, focusing on the three different ballistic goggles across the three measurement
Fig. 5 Estimated marginal means of frontal asymmetry index (yscale) and frontal alpha power (x
scale) collapsed over all fixed factors except the measurement moments, for all participants. Error
bars stand for 95% confidence intervals. Symbols shown in the legend represent the measurement
moments.
Fig. 6 Estimated marginal means of frontal asymmetry index (yscale) and frontal alpha power (x
scale) at 11-deg dazzling angle and 25% target contrast for the three different ballistic goggles at
the three measurement moments for all participants. Error bars stand for 95% confidence intervals.
Symbols shown in the legend represent the measurement moments, and the colors stand for the
different goggles.
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moments, for all participants. Despite relatively substantial error bars overall, for LEP0 goggles,
the frontal alpha power just before the shot is significantly higher compared to both 2 and 4 s after
the shot. This trend aligns with the overall pattern observed. In contrast, the sizeable error bars
associated with frontal asymmetry index estimations hinder significant comparisons within any
LEP. Among the different LEPs, it is noteworthy that the frontal asymmetry index just before the
shot with LEP0 goggles is significantly more negative than the values at 2 and 4 s after the shot
when wearing LEPY goggles, while the frontal alpha power is significantly higher than values at
2 and 4 s after the shot when wearing LEPX and LEPY and notably, also significantly higher than
the estimated value for LEPY just before the shot.
Results suggest that the cognitive and emotional states moments just before the shots are
associated with shooting performance. In particular, when wearing the LEP0 goggles, partici-
pants showed a more negative frontal asymmetry index or emotional valence and sense of avoid-
ance than when using the LEPX and LEPY goggles, which could be associated to lower scores
and longer delays. Conversely, when wearing the LEPY goggles, participants showed a more
positive frontal asymmetry index or valence and sense of approach than when using the other
goggles, and concomitantly showed higher scores and shorter delays (although not significantly
different from the performance when wearing the LEPX goggles).
Additionally, when wearing the LEP0 and especially the LEPX goggles, participants showed
much higher frontal alpha power just before the shots than in comparison with when wearing the
LEPY goggles and the baseline values. These findings may be related to a higher cognitive load
experienced with the former goggles as these showed no filter to dazzling (LEP0) or used a
stronger light filter (LEPX) than LEPY, which seemed to reduce the overall visibility.
Nonetheless, given that shooting performances were similar when wearing LEPX or LEPY,
it seems that participants adapted well to both types of light filters.
In Figs. 5and 6, it is also observed that, after the shots had taken place, both asymmetry and
frontal alpha power values approach the baseline values (0, 0). In particular, it seems that wearing
the LEPY goggles results in cognitive and emotional states more similar to the baseline state
across all three measurement moments, which may suggest a more “natural”usage of such gog-
gles. Nonetheless, it must be pointed out, that the baseline values are not obtained with partic-
ipants at rest but already engaged in the task. Consequently, their cognitive and emotional states
during the moments prior to the BEEP sound signals are also relevant for shooting performance.
3.3 Results from the Low-Background Luminance (DARK) Sets
In the 2022 trials, we conducted a distinct set of measurements under the DARK conditions,
featuring extremely low-target contrast at 0.5%, without laser dazzling and with low background
luminance. This set was designed to evaluate the performance impact of different ballistic gog-
gles (LEP0, LEPX, and LEPY) under these low-VL conditions. The initial shots with each pair of
goggles were omitted, being considered as training due to the unfamiliarity of the shooters with
the low-contrast targets.
Figure 7displays the estimated marginal means of scores and shooting delays for the DARK
dataset. An examination of the plot indicates that there were no statistically significant
differences in shooting scores when comparing the various goggles under DARK conditions.
However, there are statistically significant differences in shooting delays: delays were signifi-
cantly shorter with LEP0 goggles compared to LEPX, while LEPY goggles resulted in inter-
mediate delays. The difference in delays is consistent with the lighter tint of LEPY goggles
relative to LEPX, suggesting an influence on visibility and response time.
3.4 Comparison of the 2021 Simulator Trial with a Live Shooting Trial
Our 2021 shooting simulator campaign aimed to closely replicate the conditions of a live shoot-
ing trial (detailed in Ref. 13). This live trial was conducted on an indoor shooting range using an
assault rifle-type weapon. The 2021 simulator trial setup matched the laser irradiance, dazzling
angles, background luminance, and the use of standard ballistic goggles (LEP0) with the high-
contrast target with the live shooting trial’s conditions. However, we diverged in two aspects:
first, to better explore conditions where the dazzling effect was strong, we omitted the 22-deg
dazzling angle present in the live trial and introduced the 8-deg dazzling angle. Second, during
the live shooting campaign, shooters turned their backs to the target after each shot, firing five
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consecutive shots at the same dazzling angle and target. Replicating this turning movement in the
simulator was not feasible. To test if the nonconventional resting position disrupted muscle
memory similarly to the turning movement, we organized a preliminary simulator campaign.
In this campaign, shooters were instructed to fire at the same target position consecutively, taking
the nonconventional resting position between shots. We found that this did not disrupt muscle
memory sufficiently, leading to higher scores and shorter delays for subsequent shots, which was
opposite to what we observed in the live trial where scores decreased and delays increased sys-
tematically from shot 1 to shot 5 (as seen in Fig. 8). To address this, we implemented quasiran-
dom target position sequences, which effectively eliminated any systematic patterns in the data in
chronological order or for shots at the same target position.
Fig. 8 Estimated marginal means of (a) scores and (b) delays from the live shooting trial.13 Each
curve represents the mean score or delay for one of the five consecutive shots fired at the target,
from shot 1 (black) to shot 5 (magenta). The curves are offset slightly on the xaxis for visual clarity.
Error bars stand for 95% confidence intervals.
Fig. 7 Estimated marginal means of (a) scores and (b) delays as estimated by the linear mixed
model (model 4) from the “DARK”dataset. Error bars stand for 95% confidence intervals.
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A linear mixed model was applied to reanalyze the raw data from this live trial, providing
estimated marginal means values with 95% confidence intervals (see Fig. 8) for an easy com-
parison with the results from our simulator trial.
Figure 9compares the estimated marginal means for shooting scores and delays between the
2021 campaign and the live trial. The data from the live trial were collapsed over consecutive
shots, offering a visual comparison of shooting performance under similar conditions. Despite
the differences in protocols, the estimated marginal means of scores from both trials showed a
strong agreement, notably aligning at the 6-deg dazzling angle, where the dazzling effect was
strongest. Delays, while showing some variation, overlapped reasonably well and coincidentally
perfectly overlap at the 6-deg dazzling angle.
3.5 Comparison with Visibility Level Calculations
Based on the measured luminance levels of the targets and background (Table 1), we calculated
the VL of the white outer rings against the gray background and the black center against the white
outer rings using the Adrian/CIE visibility model: VL calculator.32 VL is calculated as the ratio of
the actual target contrast (ΔLactual) to its predetermined contrast detection threshold (ΔLthreshold ):
EQ-TARGET;temp:intralink-;e003;114;240VL ¼
ΔLactual
ΔLthreshold
:(3)
The estimates were calculated for a 20-year-old observer (mean age of the trial participants)
with brown eyes and assumed a 2-s target viewing duration. The calculation used a glare illu-
minance of 566 lux, which corresponds to the 100 μW∕cm2mean laser irradiance at the eyes of
the shooters at 532 nm.
The resulting VLs of the white outer rings against the gray background reflect the difficulty
of spotting the target before aiming the gun. On the other hand, the VLs of the black center of the
target against the white outer rings represent the actual aiming through the iron sight of the gun.
When the gun was centered on the middle of the target, the view through the aperture sight was
approximately restricted within the white outer rings of the target.
Given the relatively constant shooting delays observed in the 2021 simulator trial results
across various dazzling angles, it is reasonable to infer that the shooting scores reflect the chal-
lenge posed by laser dazzle. This makes the data from the 2021 trial ideal for comparison.
Fig. 9 Estimated marginal mean shooting (a) scores and (b) delays for the 100% contrast target
and standard ballistic goggles, obtained from the 2021 shooting simulator trial (shown in black), as
well as the estimated marginal means from the live shooting trial13 (shown in red). The error bars
stand for 95% confidence intervals.
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Figure 10 provides a comparison between the estimated marginal mean scores and the cor-
responding calculated VLs. The left scale of the graph shows the estimated marginal mean
scores, and the right scale displays the calculated VLs. This comparison reveals that for dazzling
angles ranging from 6 deg to 11 deg, there is a linear relationship characterized by a slope of
Δy∕Δx¼10∕130 and a zero intercept, effectively linking shooting performance with VL. For
larger angles, however, the shooting scores tend to plateau, indicating a limit to the decreasing
difficulty as measured by VL.
4 Conclusions
This study, using a laser dazzling shooting simulator at the Royal Military Academy, Belgium,
contributes to the broader understanding of how laser dazzle affects human shooting perfor-
mance, with a focus on accuracy and reaction times. Set in a simple, baseline scene, the research
was designed to establish initial insights into the effects of laser dazzle in a controlled environ-
ment, providing a valuable starting point for more complex future studies and the development of
virtual and augmented reality simulations.
In our trials, we employed a 532 nm green laser at irradiance levels significantly below (1/
10th) the maximum permissible exposure. We observed that this level of laser dazzle, particularly
at smaller dazzling angles, significantly affects shooting performance. Our findings, consistent
across multiple datasets, align strongly with a live shooting trial conducted on a shooting range
and correlate with VL calculations, underscoring the reliability of our simulator-based approach.
In the second phase of our research, we expanded our investigation to include lower contrast
targets and different laser eye protection ballistic goggles. Our results showed that the effects of
lower contrast were more pronounced in shooting delays under dazzle conditions than in shooting
scores. The laser eye protection goggles effectively mitigated the impact of laser dazzling within
our experimental conditions, only showing a degradation in shooting performance at the lowest
contrast and luminance levels compared to transparent ballistic goggles without laser dazzle.
The EEG data collected during the trials provided valuable insights into the cognitive and
emotional states of shooters, particularly when using different LEPs under laser-dazzling con-
ditions. EEG-derived metrics, such as frontal alpha asymmetry index and frontal alpha power,
revealed that just prior to shooting, participants exhibited more negative and avoidance feelings,
as well as increased cognitive load. Subsequently, 4 s after the shot, their emotional and cognitive
states returned to baseline, characterized by more positive and approach-oriented feelings, and a
Fig. 10 Estimated marginal means of scores for the standard ballistic goggles (LEP0) and 100%
contrast target (left scale) compared to the estimated VL for the inner black center of the target with
the white outer rings in the corresponding conditions. Error bars for the scores stand for 95% con-
fidence intervals.
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lower cognitive load. Distinct emotional and cognitive states were observed in participants when
wearing the different goggles, especially before taking the shots, which could be correlated to
shooting performance. A more negative frontal asymmetry index was associated with lower
shooting scores and longer shooting delays, as seen with transparent ballistic goggles. In contrast,
higher frontal alpha power correlated with lesser visibility in more tinted ballistic goggles with
laser eye protection, yet a more “natural”or baseline-like response was noted with less tinted
laser eye protection goggles. Both types of goggles with laser eye protection allowed the shooters
to maintain comparable shooting performance. Further studies are warranted to assess additional
EEG-derived metrics, such as engagement and attention, as well as sympathetic responses, such
as heart rate and breathing rate, as derived from PPG signals.
Looking forward, the foundational data gathered from this simple scenario will be instrumental
in guiding more advanced research. Our next steps involve incorporating more complex elements
into the simulation, such as target recognition and tracking, as well as more realistic backgrounds
and targets, to further deepen our understanding of laser dazzle effects in varied contexts.
In summary, this study not only contributes to the current understanding of laser dazzle but
also lays the groundwork for practical applications in tactical and training environments. The
insights gained can inform the development of more effective training protocols and the design
of protective gear, enhancing operational safety and performance under laser-dazzling condi-
tions. The progression toward more sophisticated simulations promises not just to broaden our
understanding of laser dazzle but also to directly impact how military and law enforcement per-
sonnel are prepared for such scenarios.
5 Appendix
5.1 Linear Mixed Effect Models: SPSS Syntax
The variables in the models are as follows.
(1) negAngle: The dazzling angles (17-deg, 11-deg, 8-deg, 6-deg with 90 standing for the no
dazzling laser condition), recoded by multiplying by −1, so that the reference category
became the 6-deg angle. The reason for this was that the highest number of observations
was at this angle, ordinal variable.
(2) contrast: target contrast, ordinal variable.
(3) goggles: worn googles, nominal variable.
(4) campaignID: trial identification, nominal variable.
(5) repeated: repetitions of a shot under the same condition in a given trial by a shooter, scale
variable.
(6) at: measurement moment identification, nominal variable.
(7) shooter_id: participant identification, nominal variable, subjects of the model.
(8) delay_s: dependent, scale variable.
(9) score: dependent, scale variable
(10) asym: frontal asymmetry index, dependent, scale variable.
(11) arou: frontal alpha power, dependent, scale variable.>
5.2 Score
MIXED score BY negAngle contrast goggles campaignID
/CRITERIA=DFMETHOD(SATTERTHWAITE) CIN(95) MXITER(100) MXSTEP(10)
SCORING(1)
SINGULAR(0.000000000001) HCONVERGE(0, ABSOLUTE) LCONVERGE(0,
ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
/FIXED=negAngle*contrast*goggles*campaignID | SSTYPE(3)
/METHOD=REML
/PRINT=CPS CORB DESCRIPTIVES HISTORY(1) SOLUTION TESTCOV
/RANDOM=INTERCEPT | SUBJECT(shooter_id) COVTYPE(VC) SOLUTION
/REPEATED=negAngle*contrast*goggles*repeated*campaignID |
SUBJECT(shooter_id) COVTYPE(ARH1)
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/EMMEANS=TABLES(negAngle*contrast*goggles)
/EMMEANS=TABLES(OVERALL).
5.3 Delay
MIXED delay_s BY negAngle contrast goggles campaignID
/CRITERIA=DFMETHOD(SATTERTHWAITE) CIN(95) MXITER(100) MXSTEP(10)
SCORING(1)
SINGULAR(0.000000000001) HCONVERGE(0, ABSOLUTE) LCONVERGE(0,
ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
/FIXED=negAngle*contrast*goggles*campaignID | SSTYPE(3)
/METHOD=REML
/PRINT=CPS CORB DESCRIPTIVES HISTORY(1) SOLUTION TESTCOV
/RANDOM=INTERCEPT | SUBJECT(shooter_id) COVTYPE(VC) SOLUTION
/REPEATED=negAngle*contrast*goggles*repeated*campaignID |
SUBJECT(shooter_id) COVTYPE(ARH1)
/EMMEANS=TABLES(negAngle*contrast*goggles)
/EMMEANS=TABLES(OVERALL).
5.4 Frontal Asymmetry Index
MIXED asym BY at negAngle contrast goggles
/CRITERIA=DFMETHOD(SATTERTHWAITE) CIN(95) MXITER(500) MXSTEP(100)
SCORING(1)
SINGULAR(0.000000000001) HCONVERGE(0, ABSOLUTE) LCONVERGE(0,
ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
/FIXED=goggles*contrast*negAngle*at | SSTYPE(3)
/METHOD=REML
/PRINT=CPS CORB COVB DESCRIPTIVES G LMATRIX R SOLUTION TESTCOV
/REPEATED=goggles*contrast*at*negAngle*campaignID | SUBJECT(shooter_id)
COVTYPE(ARH1)
/EMMEANS=TABLES(at)
/EMMEANS=TABLES(at*goggles)
/EMMEANS=TABLES(at*contrast*goggles)
/EMMEANS=TABLES(at*negAngle*contrast*goggles)
/EMMEANS=TABLES(OVERALL).
5.5 Frontal Alpha Power
MIXED arou BY at negAngle contrast goggles
/CRITERIA=DFMETHOD(SATTERTHWAITE) CIN(95) MXITER(500) MXSTEP(100)
SCORING(1)
SINGULAR(0.000000000001) HCONVERGE(0, ABSOLUTE) LCONVERGE(0,
ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
/FIXED=goggles*contrast*negAngle*at | SSTYPE(3)
/METHOD=REML
/PRINT=CPS CORB COVB DESCRIPTIVES G LMATRIX R SOLUTION TESTCOV
/REPEATED=goggles*contrast*at*negAngle*campaignID | SUBJECT(shooter_id)
COVTYPE(ARH1)
/EMMEANS=TABLES(at)
/EMMEANS=TABLES(at*goggles)
/EMMEANS=TABLES(at*contrast*goggles)
/EMMEANS=TABLES(at*negAngle*contrast*goggles)
/EMMEANS=TABLES(OVERALL).
Disclosures
The authors have no relevant financial interests in the manuscript and no other potential conflicts of
interest to disclose.
Földes et al.: Investigating the impact of laser dazzling on shooting performance. . .
Optical Engineering 034101-17 March 2024 •Vol. 63(3)
Code and Data Availability
The data supporting the findings of this study, involving laser dazzling shooting simulator experi-
ments, are not publicly available due to participant privacy and concerns regarding the potential
misuse of sensitive information. Researchers interested in accessing the data can request it
directly from the corresponding author at tomas.foldes@mil.be.
Acknowledgments
The shooting simulator has been developed through the collaborative efforts of the NATO SET-249
Research Group, now succeeded by SET-323. Our gratitude extends to all members of this group.
Additionally, we would like to thank C. Perneel for his guidance in statistical modeling. We also
would like to acknowledge the support from the Royal Higher Institute for Defense and the Ministry
of Defense of Belgium for their generous funding through the DAP21/09 project. We were also
grateful to Fundação para a Ciência e Tecnologia for partially funding this work under the project
(No. UIDB/00645/2020) and the PhD (No. 2021.08306.BD). This manuscript is partially based on
scientific content previously reported at SPIE Defense + Security 2023.33
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Tomas Földes is an experimental physicist with a background in the field of laser spectroscopy,
instrument development, and indoor air quality measurement. He has been working at the Royal
Military Academy since 2021 on the subject of laser dazzle and laser safety.
Helena Rico Pereira is a biomedical engineer with experience in physiological signal process-
ing. She is currently doing her PhD in biomedical engineering focused on the diagnosis of neuro-
degenerative disorders through medical imaging biomarkers and artificial intelligence algorithms
at Nova School of Science and Technology and the Institute of Biophysics and Biomedical
Engineering at the University of Lisbon.
Sebastian Stutz is an experimental physicist with a background in investigations of semicon-
ductor lasers. He has been working at the Fraunhofer Institute of Optronics, System Technologies
and Image Exploitation since 2019 on the subject of optronics and laser safety.
Michael Henrichsen is a research associate at Fraunhofer IOSB, Ettlingen, Germany. He is the
head of the Optronic Analysis Systems and Laser Effects Group since 2022. He received his
master of science degree in physics from the University of Constance, Germany, in 2012.
His main research focus is on laser effects and infrared imaging.
Hugo Alexandre Ferreira is an associate professor at the University of Lisbon specializing in
nanotechnologies applied to biomedicine, with a focus on neurosciences, oncology, and digital
health. He founded Haloris Nanotechnologies and holds advisory roles in various medical tech
startups.
Marijke Vandewal is a military professor in the Communications, Information, Systems, and
Sensors Department at the Royal Military Academy, Brussels, Belgium. After serving in the
Belgian Air Force, she embarked on an academic career in 2000, managing several national,
ESA, and EU research projects since 2009. Specializing in optronics sensors and lasers, she
currently leads the Laser and Optronics Research Unit.
Földes et al.: Investigating the impact of laser dazzling on shooting performance. . .
Optical Engineering 034101-19 March 2024 •Vol. 63(3)
