25RS/ 25RS-S/ 55RS/ 10RS-S Diffuse Specular Reflectance Standards0 pages

diameter (OL 10RS-S) sizes. These are front surface
coated aluminum mirrors with a magnesium fluoride

OL 25RS, 25RS-S, 55RS,
and 10RS-S
Diffuse and Specular
Reflectance Standards
overcoat. They are used as specular reflectance standards
for a wide variety of instruments and applications.
They are only available in calibrated versions:

OL 25RS and OL 55RS
Diffuse Reflectance Standards
The Gooch and Housego diffuse reflectance standards are
available in 2 x 2 inch (OL 25RS) or 5 X 5 inch (OL 55RS)
sizes.
The standards consist of pressed PTFE powder
(Polytetrafluoroethylene) packed to a density of 1.0g/cm3 in
a blackened aluminum holder. They are ideal as standards
of diffuse reflectance, bi-directional reflectance distribution
factor (BRDF), and as a target for irradiance to radiance
conversion.
They are available in calibrated and uncalibrated versions:

•
•

OL 25RS-U and OL 55RS-U: Uncalibrated

•

Optional certifications:

OL 25RS and OL 55RS: Certified for hemispherical
1
diffuse reflectivity relative to NIST (350 - 1100nm)
Extended
hemispherical
diffuse
reflectivity
certification (350 - 2500nm)
Bi-directional reflectance distribution factor for any
specified wavelength range (350 - 2500nm) and
2
incidence/reflection angles (e.g. 0°/45°)

•

OL 25RS-S: Calibrated for unpolarized specular
reflectance at 10° incidence angle (350 - 1100nm)

•

OL 10RS-S: Calibrated for unpolarized specular
reflectance at 10° incidence angle (350 - 1100nm)

•

Optional calibrations:
Over specified wavelength ranges (200nm-30µm)
At specified incidence angles (10° to 75° [OL
25RS-S] or 60° [OL 10RS-S])
At s-, p-, or other specified polarizations

Specular reflectance is based on the OL 750 Automated
Spectroradiometric Measurement System with the OL 75075MA Variable Angle Specular Reflectance Attachment.
The measurement is performed using a "self-calibrating"
technique that consists of performing a spectral scan with
the detector measuring the incident flux. Following the
calibration scan, the sample is placed in the sample holder,
rotated to the specified incident angle, and reflected flux is
measured. The specular reflectance is the ratio of the
scans.

OL 25RS–S and OL 10RS-S
Specular Reflectance Standards
The Gooch and Housego specular reflectance standards are
available in 2 x 2 inch (OL 25RS-S) or circular 1-inch

1

2

Based on the methods and results of: V.R. Weidner and J.J. Hsia,
“Reflection Properties of Pressed Polytetrafluoroethylene Powder,” J.
Opt. Soc. Am. 71, 856-861(1981).
A minimum angle of 20° between incidence and reflection is required.

Contact: orlandosales@goochandhousego.com

www.GHinstruments.com

As part of our policy of continuous product improvement, we reserve the right to change specifications at any time
Bulletin 161 / Rev 7-14
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