According to the upcoming international photobiological safety standard for image projectors IEC 62471-5, the risk group of the projector is to be determined at a distance of 1 meter from the projector closest point of human access.

This document discusses biophysical data for Risk Group 2 (RG2) projectors which support the reference distance of 1 meter and in addition a risk analysis for exposure distances closer than 1 meter is provided. The analysis is based on the two main relevant parameters: the safety margin between injury threshold and emission limit, and the diameter of the pupil of the eye. The injury threshold for retinal thermal injury can be modeled well with the Seibersdorf Laboratories Injury Model and was calculated for the relevant wavelength distributions, retinal image sizes and exposure durations. The eye pupil diameter will be accounted for by data identified in the literature, considering that in order to accommodate to an apparent source at close distances, the pupil can be assumed to constrict due to the near triad of accommodation.

It is shown that the risk for retinal thermal injury from image projectors classified as RG2 under IEC 62471-5 can be considered as low to negligible.

Topics
Diseases and conditions, Vitamins
1.
IEC 62471-5
(
2014
)
Photobiological Safety of Lamps and Lamp Systems – Part 5 Image Projectors
, 76/504/CDV
2.
IEC 62471
(
2006
)
Photobiological Safety of Lamps and Lamp Systems
3.
Sliney
DH
,
Stack
C
,
Schnuelle
D
,
Parkinson
J
 (
2013
)
Optical safety of comparative theater projectors
,
Health Physics
106
(
3
),
353
–
364
doi:
https://doi.org/10.1097/HP.0b013e3182a5fc47
Google Scholar
Crossref
Search ADS
 
4.
Sliney
D
,
Wolbarsht
M
 (
1980
)
Safety with lasers and other optical sources
,
Springer
US
Google Scholar
Crossref
Search ADS
 
5.
Schulmeister
K.
 (
2013
)
The radiance of the sun, a 1 mW laser pointer and a phosphor emitter
,
ILSC 2013 Conf. Proc.
paper #107.
Google Scholar
Crossref
Search ADS
 
6.
Schulmeister
Κ.
,
Jean
M.
 (
2010
)
The risk of retinal injury from Class 2 and visible Class 3R lasers
;
Medical Laser Application
25
,
99
–
110
. doi:
https://doi.org/10.1016/j.mla.2010.01.005
Google Scholar
Crossref
Search ADS
 
7.
Sliney
DH
,
Mellerio
J
,
Gabel
VP
,
Schulmeister
K.
 (
2002
)
What is the meaning of threshold in laser injury experiments? Implications for human exposure limits
.
Health Phys
82
:
335
–
347
. doi:
https://doi.org/10.1097/00004032-200203000-00006
Google Scholar
Crossref
Search ADS
PubMed
 
8.
Stuck
B.E.
 (
1984
) Ocular susceptibility to laser radiation: human vs Rhesus monkey, Letterman Army Institute of Research, Handbook of laser bioeffects assessment volume 1, Chapter 4, San Francisco.
9.
Söderberg
P.
,
Stuck
B.E.
 et al (
2013
)
ICNIRP Guidelines on limits of exposure to incoherent visible and infrared radiation
,
Health Phys
105
:
1
. doi:
https://doi.org/10.1097/HP.0b013e3182983a22
Google Scholar
Crossref
Search ADS
PubMed
 
10.
Thomas L.
Slamovits
,
Joel S.
Glaser
 and
Joyce N.
Mbekeani
, (
2006
)
The Pupils and Accommodation, Vol. 2 Chapter 15, in: Duane’s Ophthalmology on CD-ROM
, 2006 Edition,
Lippincott Williams & Wilkins
Google Scholar
 
11.
Personal communication Frank Schaeffel (2014), Per Söderberg (2012), Charles Campbell (2014)
12.
Campbell
FW
,
Gregory
A.H.
 (
1960
)
Effect of Size of Pupil on Visual Acuity
,
Letters Nature
187
,
1121
–
1123
doi:
https://doi.org/10.1038/1871121c0
Google Scholar
Crossref
Search ADS
 
13.
Donnelly
W
,
Roorda
A
 (
2003
)
The optimal pupil size in the human eye for axial resolution
,
JOptSocAm
20
,
2010
–
15
Google Scholar
 
15.
Glasser
A
 (
2011
), Accommodation, Chapter 3, in:
Adler’s Physilogy of the Eye
, 11th edition,
Elsevier Saunders
Google Scholar
 
16.
Charman
WN
,
Radhakrishnan
H
 (
2009
),
Accommodation, pupil diameter and myopia
;
Ophthal. Physiol. Opt.
29
,
72
–
79
doi:
https://doi.org/10.1111/j.1475-1313.2008.00611.x
Google Scholar
Crossref
Search ADS
 
17.
Oyster
,
C.
,
The Human Eye
(Chapter 10, Sinauer Associates, Massachusetts,
1999
)
18.
Kasthurirangan
S.
 and
Glasser
A.
,
Age related changes in the characteristics of the near pupil response
(Vision Research 46, 1393-1403,
2006
)
Google Scholar
 
19.
Schaeffel
F
,
Wilhelm
H
,
Zrenner
E
 (
1993
),
Interindividual variability in the dynamics of natural accommodation in humans: relation to age and refractive errors
,
J Physiology
461
,
301
–
320
doi:
https://doi.org/10.1113/jphysiol.1993.sp019515
Google Scholar
Crossref
Search ADS
 
20.
Gislen
A
,
Gustafsson
J
,
Kroger
RHH
 (
2008
),
The accommodative pupil responses of children and young adults at low and intermediate levels of ambient illumination
,
Vision Research
48
,
989
–
993
doi:
https://doi.org/10.1016/j.visres.2008.01.022
Google Scholar
Crossref
Search ADS
 
21.
Jean
M.
 and
Schulmeister
K.
 (
2013
)
Validation of a computer model to predict laser induced thermal injury thresholds of the retina
,
ILSC 2013 Conf. Proc.
paper #1002.
Google Scholar
Crossref
Search ADS
 
22.
Jean
M
 and
Schulmeister
K
 (
2014
) Modeling of Laser-Induced Thermal Damage to the Retina and the Cornea, in:
Image Analysis and Modeling in Ophthalmology
, Ch. 15, Ed.:
Ng
E
 et al,
CRC Press
2014
Google Scholar
 
23.
Lund
D.J.
,
Edsall
P.
 and
Stuck
B.E.
 (
2001
)
Ocular hazards of Q-switched blue wavelength lasers
,
Proc. of SPIE
, vol.
4246
p.
44
–
53
.
https://doi.org/10.1117/12.426722
Google Scholar
Crossref
Search ADS
 
24.
Schulmeister
Κ.
,
Stuck
B.E.
 et al (
2011
)
Review of thresholds and recommendations for revised exposure limits for laser and optical radiation for thermally induced retinal injury
,
Health Phys
100
:
2
. doi:
https://doi.org/10.1097/HP.0b013e3181ea51e3
Google Scholar
 
25.
Atchison
D.A.
 and
Smith
G.
 (
2000
)
Optics of the Human Eye
,
Edinburgh
:
Butterworth-Heinemann
.
Google Scholar
 
26.
European Union Commission Decision 2010/15/EU
,
Risk Assessment Guidelines for Consumer products
,
33
–
64
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