345 Radiometric & Photometric Calibration Standard0 pages

OL 345
Radiometric and
Photometric
Calibration Standard
GENERAL DESCRIPTION
The OL 345 Calibration Standard consists of a 45-watt
tungsten-halogen lamp and a removable 2-inch diameter
flashed-opal diffuser mounted in an air-cooled,
machined, cylindrical housing. With the diffuser in place,
the uniform, 15.5 cm² radiating source serves as a
standard of spectral radiance over the wavelength range
of 350 to 1100 nm and as a standard of luminance.
When the diffuser is removed, the OL 345 serves as a
standard of spectral irradiance from 250 to 2500 nm and
as a standard of illuminance. The OL 345 can also be
obtained with the source operating at a specified color
temperature.
A filter holder is provided for inserting 2-inch square
filters into the unit between the lamp and the diffuser.
Spectral shaping filters for simulation of various types of
CRT phosphor screens and for obtaining color
temperatures up to 6000 K are available. Narrow band
interference filters for obtaining discrete spectral
radiances and irradiances are also available.

APPLICATION
The OL 345 is a rugged, versatile radiometric and
photometric standard capable of accurately calibrating a
large variety of light measuring instrumentation. When
the 2-inch diameter opal diffuser is attached, the unit is
ideal for calibrating such instrumentation as telephotometers,
microphotometers,
telespectroradiometers, etc. When the opal is removed, the
absolute calibration of spectral irradiance and
illumination measuring instrumentation is easily
accomplished.

Contact: orlandosales@goochandhousego.com

The ability to insert either narrow band interference filters
or spectral shaping filters in the beam enables the
calibration of various radiometers and photometers to be
made quickly and accurately.

TYPE OF CALIBRATION

MODEL NO.

Uncalibrated ............................................................ OL 345U
Spectral Irradiance (250-2500 nm)
& Spectral Radiance (350-1100 nm) ....................... OL 345R
Illuminance, Luminance
& Color Temperature ................................................ OL 345P
All of the above ...................................................... OL 345RP

Contact Gooch and Housego directly for information
concerning calibrations with spectral shaping filters and
interference filters. All calibrations are performed at
6.500 amps unless otherwise specified. Calibration at a
specific color temperature is available as an option.

SPECIFICATIONS
Spectral Irradiance @ 650 nm .............. 0.6 µW/cm²nm (typical)
Spectral Radiance @ 650nm .......... 0.45 µW/sr cm²nm (typical)
Illuminance @ 6.500 amps ................................... 24 fc (typical)
Luminance @ 6.500 amps .................................... 65 fL (typical)
Radiometric Accuracy .......................................± 2% @ 650 nm
..........................................................................± 4% @ 250 nm
Photometric Accuracy ..................................................... ± 1½%
Stability ................................................ 50 hrs. for ± 1% change
Lamp Power............................................ 45 watts (6.500 amps)
Diameter .................................................................... 5½ inches
The OL 410 Programmable DC Current Source is recommended to power
the OL 345 (see Bulletin 121)

www.GHinstruments.com

As part of our policy of continuous product improvement, we reserve the right to change specifications at any time
Bulletin 43 / Rev 9-02
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