Sunglasses, pupil dilation, and solar ultraviolet irradiation of the human lens and retina

Herbert L. Hoover

doi:10.1364/AO.26.000689

Applied Optics
Vol. 26,
Issue 4,
pp. 689-695
(1987)
•https://doi.org/10.1364/AO.26.000689

Sunglasses, pupil dilation, and solar ultraviolet irradiation of the human lens and retina

Herbert L. Hoover

Not Accessible

Your library or personal account may give you access

Get PDF
Email
Share
Get Citation
Copy Citation Text
Herbert L. Hoover, "Sunglasses, pupil dilation, and solar ultraviolet irradiation of the human lens and retina," Appl. Opt. 26, 689-695 (1987)

Export Citation
- BibTex
- Endnote (RIS)
- HTML
- Plain Text
Citation alert
Save article

Abstract

The supposition that, because of pupil dilation, there are greater influxes of solar UV and short-wavelength visibile radiation when some sunglasses are worn is wrong. It is based on an incomplete and, therefore, misleading analysis. That analysis is particularly defective in ignoring the attenuation of the more highly actinic shorter wavelengths. This paper provides the most nearly complete analysis that is now possible. It treats both the geometric and radiometric aspects of ocular irradiation. A survey of over 400 retail sunglass lenses of all types showed that all would reduce UV radiation densities in all parts of the crystalline lens and on the retina. With spectral actinic weighting, the effective reductions would be even greater.

Full Article | PDF Article

More Like This

Solar ultraviolet irradiation of human cornea, lens, and retina: equations of ocular irradiation

Herbert L. Hoover
Appl. Opt. 25(3) 359-368 (1986)

Ultraviolet windows in commercial sunglasses

Wayne J. Anderson and Radames K. H. Gebel
Appl. Opt. 16(2) 515-517 (1977)

Aging of the human lens

Joel Pokorny, Vivianne C. Smith, and Margaret Lutze
Appl. Opt. 26(8) 1437-1440 (1987)

Previous Article Next Article

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (5)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Tables (4)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Equations (5)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Adapting field	S2 sun (Moon)³	Snow under full suna	Horizon sky clear daya	Overcast daya
B	86480	16000	3000	300 cd/m²
d_u [Eq. (2)]b	1.16	1.57	2.05	2.79 mm
d_u [Eq. (3)]b	1.33	1.74	2.25	3.12 mm
d(3)/d(2)	1.14	1.11	1.10	1.12
With 10% luminous transmittance sunglass lens
d_f [Eq. (2)]	1.74	2.24	2.79	3.67 mm
d_f [Eq. (3)]	1.92	2.47	3.12	4.17 mm
d(3)/d(2)	1.10	1.10	1.12	1.16
Pupillary area ratios: $A$ = A_f/A_u
[Eq. (2)]	2.23	2.03	1.86	1.66
[Eq. (3)	2.07	2.01	1.92	1.80
$A$ (3)/ $A$ (2)	0.93	0.99	1.03	1.08

(1)	Distances along the optic axis from the anterior pole of the cornea:
	To center of curvature of anterior surface of cornea	7.98 mm
	To center of curvature of posterior surface of cornea	7.37 mm
	To center of curvature of anterior surface of lens	13.74 mm
	To center of curvature of posterior surface of lens	1.43 mm
(2)	Radii of curvature of spherical surfaces:
	Anterior surface of cornea	7.98 mm
	Posterior surface of cornea	6.22 mm
	Anterior surface of lens	10.20 mm
	Posterior surface of lens	6.17 mm
(3)	Refractive indices of ocular media:
	Cornea	1.376
	Aqueous humor	1.336
	Crystalline lens	1.42
(4)	Axial thickness of lens:	4.00 mm

(1)	Pupil diameters by Eq. (3)
	Adapting field luminance (cd/m²)		16,000	1,600
	Pupil diameter (mm)		1.74	2.47
(2)	Angles of intersection of peripheral rays with optic axis
	External angles
	55°	Near-side ray (deg)	44.87	45.68
		Far-side ray (deg)	40.66	39.68
	0°	Near-side ray (deg)	1.92	2.74
		Far-side ray (deg)	−1.92	−2.74
(3)	Comparison of areas irradiated by direct (unscattered) rays on a virtual surface at the midplane of the lens
		Diameter	d_u = 5.10 mm	d_f = 5.83 mm
	Ratios: midplane/anterior surface
		Area	8.58	5.56
		Irradiance	0.12	0.18
	Irradiance ratio: with/without sunglass
	By geometric analysis alone			1.54
	By combined radiometric geometric and analysisa
		Uniformly weighted (W = 1)		0.66
		Spectrally selectively weighted		0.33

(1)	Exposure situationa: U.S.A., 36° N. lat, 3-km altitude, 1 Apr., solar noon, clear day; ground cover, snow: R = 0.60; adapting field luminance: 16,000 cd/m².
(2)	Sunglass lens	AG model 1 Dark brown	1984 Dark brown	1984 worst case Gradient grayb	Photochromic Brownc
	Lens transmittances
	Luminous, T_v (%)	12.0	23.0	12.1	24.2
	Average UVB, T_B (%)	0	0	2.2	0
	Average UVA, T_A (%)	39.8	13.8	15.3	1.5
	Pupil area ratio	1.90	1.55	1.89	1.55
	Maximum of T_f(λ) · $A$	1.30	0.64	0.32	0.073
	UV wavelength of max (nm)	370	370	355	380
	Relative admittance to lensd
	With uniform spectral weighting
	UVB (290–315 nm) ρ_B	0	0	0.096	0
	UV (290–380 nm) ρ	0.84	0.27	0.30	0.029
	With spectral weighting derived from Bachem13
	UVB	0	0	0.070	0
	UV	0.42	0.102	0.196	0.011

Adapting field	S2 sun (Moon)³	Snow under full suna	Horizon sky clear daya	Overcast daya
B	86480	16000	3000	300 cd/m²
d_u [Eq. (2)]b	1.16	1.57	2.05	2.79 mm
d_u [Eq. (3)]b	1.33	1.74	2.25	3.12 mm
d(3)/d(2)	1.14	1.11	1.10	1.12
With 10% luminous transmittance sunglass lens
d_f [Eq. (2)]	1.74	2.24	2.79	3.67 mm
d_f [Eq. (3)]	1.92	2.47	3.12	4.17 mm
d(3)/d(2)	1.10	1.10	1.12	1.16
Pupillary area ratios: $A$ = A_f/A_u
[Eq. (2)]	2.23	2.03	1.86	1.66
[Eq. (3)	2.07	2.01	1.92	1.80
$A$ (3)/ $A$ (2)	0.93	0.99	1.03	1.08

Abstract

Cited By

Figures (5)

Tables (4)

Equations (5)

Applied Optics