Investigating the optical translucency of Spectralon using BSSRDF measurements

Lou Gevaux; Dipanjana Saha; Gaël Obein

doi:10.1364/AO.491929

Applied Optics
Vol. 62,
Issue 18,
pp. 5003-5013
(2023)
•https://doi.org/10.1364/AO.491929

Investigating the optical translucency of Spectralon using BSSRDF measurements

Lou Gevaux, Dipanjana Saha, and Gaël Obein

Not Accessible

Your library or personal account may give you access

Get PDF
Email
Share
Get Citation
Copy Citation Text
Lou Gevaux, Dipanjana Saha, and Gaël Obein, "Investigating the optical translucency of Spectralon using BSSRDF measurements," Appl. Opt. 62, 5003-5013 (2023)

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

Check for updates

Abstract

Translucent materials have the property of reflecting light beyond the illumination point due to subsurface light propagation in the material. These reflectance properties can be characterized using the bidirectional scattering-surface reflectance distribution function (BSSRDF), a radiometric quantity that is a function of spatial, angular, spectral, and polarization parameters. At very small scales, we have observed that Spectralon, a commercial material widely used as a diffuse reflectance calibration standard, can be regarded as translucent. This can generate measurement errors and limit Spectralon’s reliability as a calibration artefact for instruments that measure optical quantities on very small surfaces. To characterize the translucent properties of Spectralon, we have measured its BSSRDF using an experimental setup based on a goniospectrophotometer with a spatial scanning system for detection. In the present study, we show that Spectralon cannot be considered an opaque material at small scales (below 1 mm). For instrument measuring on small areas, Spectralon can be used for calibration only when the illumination area and the observation area differ by more than 1 mm in radius.

Full Article | PDF Article

More Like This

Primary facility for traceable measurement of the BSSRDF

Pablo Santafé-Gabarda, Alejandro Ferrero, Néstor Tejedor-Sierra, and Joaquín Campos
Opt. Express 29(21) 34175-34188 (2021)

Underwater spectral reflectance measurements: the reflectance standard submersion factor and its impact on derived target reflectance

Brandon J. Russell and Heidi M. Dierssen
Appl. Opt. 62(24) 6299-6306 (2023)

Evaluating edge loss in the reflectance measurement of translucent materials

Lou Gevaux, Lionel Simonot, Raphael Clerc, Morgane Gerardin, and Mathieu Hebert
Appl. Opt. 59(28) 8939-8950 (2020)

Previous Article Next Article

Data availability

Data underlying the results presented in this paper are not publicly available at this time but may be obtained from the authors upon reasonable request.

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 (11)

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 (2)

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 (10)

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

Uncertainty Source	Notation	Value	Comments
Area of the FOV	$u_{A_{F O V}} / A_{F O V}$	3.8%	Calculated from the uncertainty on $\emptyset_{F O V}$
Solid angle	$u_{Ω_{r}} / Ω_{r}$	0.5%	Calculated from the uncertainty on the distance (0.1%) and on the diaphragm diameter (0.2%)
Reading of the source	$u_{L_{s o u r c e}} / L_{s o u r c e}$	2%	Accounts for the repeatability, the source stability, and the alignment of the detector by the operator
Reading of the signal-dark	$\frac{u_{L_{r}}^{2} + u_{L_{r, d a r k}^{2}}}{{(L_{r} - L_{r, d a r k})}^{2}}$	0.3%–25%	Repeatability
Total	$u_{B S S R D F} / B S S R D F$	4%–25%	Combined uncertainty expressed for a coverage factor $k = 1$

Sample, Geometry	BRDF Obtained from Eq. (8)	BRDF	Correction Factor
Spectralon, (0°:10°) #1	$0.465 {s r}^{- 1}$	$0.331 {s r}^{- 1}$	0.712
Spectralon, (0°:10°) #2	$0.445 {s r}^{- 1}$	$0.331 {s r}^{- 1}$	0.744
Spectralon, (0°:30°) #1	$0.483 {s r}^{- 1}$	$0.322 {s r}^{- 1}$	0.667
Spectralon, (0°:30°) #2	$0.440 {s r}^{- 1}$	$0.322 {s r}^{- 1}$	0.732
White Resin, (0°:10°)	$0.413 {s r}^{- 1}$	$0.296 {s r}^{- 1}$	0.717
Average value			0.714

Uncertainty Source	Notation	Value	Comments
Area of the FOV	$u_{A_{F O V}} / A_{F O V}$	3.8%	Calculated from the uncertainty on $\emptyset_{F O V}$
Solid angle	$u_{Ω_{r}} / Ω_{r}$	0.5%	Calculated from the uncertainty on the distance (0.1%) and on the diaphragm diameter (0.2%)
Reading of the source	$u_{L_{s o u r c e}} / L_{s o u r c e}$	2%	Accounts for the repeatability, the source stability, and the alignment of the detector by the operator
Reading of the signal-dark	$\frac{u_{L_{r}}^{2} + u_{L_{r, d a r k}^{2}}}{{(L_{r} - L_{r, d a r k})}^{2}}$	0.3%–25%	Repeatability
Total	$u_{B S S R D F} / B S S R D F$	4%–25%	Combined uncertainty expressed for a coverage factor $k = 1$

Sample, Geometry	BRDF Obtained from Eq. (8)	BRDF	Correction Factor
Spectralon, (0°:10°) #1	$0.465 {s r}^{- 1}$	$0.331 {s r}^{- 1}$	0.712
Spectralon, (0°:10°) #2	$0.445 {s r}^{- 1}$	$0.331 {s r}^{- 1}$	0.744
Spectralon, (0°:30°) #1	$0.483 {s r}^{- 1}$	$0.322 {s r}^{- 1}$	0.667
Spectralon, (0°:30°) #2	$0.440 {s r}^{- 1}$	$0.322 {s r}^{- 1}$	0.732
White Resin, (0°:10°)	$0.413 {s r}^{- 1}$	$0.296 {s r}^{- 1}$	0.717
Average value			0.714

Abstract

Data availability

Cited By

Figures (11)

Tables (2)

Equations (10)

Applied Optics