Optical power calibrator based on a stabilized green He-Ne laser and a cryogenic absolute radiometer

Research output: Contribution to journalArticleScientificpeer-review

46 Citations (Scopus)

Abstract

An optical power calibrator is described whose overall calibration uncertainty is less than 10/sup -4/ for an optical power of 0.13 mW.
The laser light source of the system operates at a wavelength of 543.5 nm, being close to the wavelength at which the candela is defined, 555 nm. A stable optical power is achieved by stabilizing the intensity and the frequency of a green He-Ne laser. The optical power is detected by a cryogenic absolute radiometer based on the principle of electrical substitution radiometry. It can be used to measure up to 0.5 mW in the visible and near-infrared region with a 3 sigma uncertainty of about 5*10/sup -5/.
The factors limiting the overall uncertainty of the calibrator are analyzed: the conductance fluctuations of the temperature sensor in the absorption cavity and the beam scatter are found to be the most significant error sources.
Limited absorptivity of the cavity (0.99998) and the background radiation cause additional uncertainty. The system is controlled by a microcomputer with self-check and autocalibration features.
Original languageEnglish
Pages (from-to)558-564
JournalIEEE Transactions on Instrumentation and Measurement
Volume38
Issue number2
DOIs
Publication statusPublished - 1989
MoE publication typeA1 Journal article-refereed

Fingerprint

Radiometers
radiometers
Cryogenics
cryogenics
cavities
Lasers
microcomputers
background radiation
temperature sensors
wavelengths
lasers
absorptivity
light sources
substitutes
Wavelength
Radiometry
causes
Temperature sensors
Microcomputers
Light sources

Cite this

@article{22e70783de0241c2b2d1d33647b4fd31,
title = "Optical power calibrator based on a stabilized green He-Ne laser and a cryogenic absolute radiometer",
abstract = "An optical power calibrator is described whose overall calibration uncertainty is less than 10/sup -4/ for an optical power of 0.13 mW. The laser light source of the system operates at a wavelength of 543.5 nm, being close to the wavelength at which the candela is defined, 555 nm. A stable optical power is achieved by stabilizing the intensity and the frequency of a green He-Ne laser. The optical power is detected by a cryogenic absolute radiometer based on the principle of electrical substitution radiometry. It can be used to measure up to 0.5 mW in the visible and near-infrared region with a 3 sigma uncertainty of about 5*10/sup -5/. The factors limiting the overall uncertainty of the calibrator are analyzed: the conductance fluctuations of the temperature sensor in the absorption cavity and the beam scatter are found to be the most significant error sources. Limited absorptivity of the cavity (0.99998) and the background radiation cause additional uncertainty. The system is controlled by a microcomputer with self-check and autocalibration features.",
author = "Timo Varpula and Heikki Sepp{\"a} and Juha-Matti Saari",
year = "1989",
doi = "10.1109/19.192347",
language = "English",
volume = "38",
pages = "558--564",
journal = "IEEE Transactions on Instrumentation and Measurement",
issn = "0018-9456",
publisher = "IEEE Institute of Electrical and Electronic Engineers",
number = "2",

}

Optical power calibrator based on a stabilized green He-Ne laser and a cryogenic absolute radiometer. / Varpula, Timo; Seppä, Heikki; Saari, Juha-Matti.

In: IEEE Transactions on Instrumentation and Measurement, Vol. 38, No. 2, 1989, p. 558-564.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Optical power calibrator based on a stabilized green He-Ne laser and a cryogenic absolute radiometer

AU - Varpula, Timo

AU - Seppä, Heikki

AU - Saari, Juha-Matti

PY - 1989

Y1 - 1989

N2 - An optical power calibrator is described whose overall calibration uncertainty is less than 10/sup -4/ for an optical power of 0.13 mW. The laser light source of the system operates at a wavelength of 543.5 nm, being close to the wavelength at which the candela is defined, 555 nm. A stable optical power is achieved by stabilizing the intensity and the frequency of a green He-Ne laser. The optical power is detected by a cryogenic absolute radiometer based on the principle of electrical substitution radiometry. It can be used to measure up to 0.5 mW in the visible and near-infrared region with a 3 sigma uncertainty of about 5*10/sup -5/. The factors limiting the overall uncertainty of the calibrator are analyzed: the conductance fluctuations of the temperature sensor in the absorption cavity and the beam scatter are found to be the most significant error sources. Limited absorptivity of the cavity (0.99998) and the background radiation cause additional uncertainty. The system is controlled by a microcomputer with self-check and autocalibration features.

AB - An optical power calibrator is described whose overall calibration uncertainty is less than 10/sup -4/ for an optical power of 0.13 mW. The laser light source of the system operates at a wavelength of 543.5 nm, being close to the wavelength at which the candela is defined, 555 nm. A stable optical power is achieved by stabilizing the intensity and the frequency of a green He-Ne laser. The optical power is detected by a cryogenic absolute radiometer based on the principle of electrical substitution radiometry. It can be used to measure up to 0.5 mW in the visible and near-infrared region with a 3 sigma uncertainty of about 5*10/sup -5/. The factors limiting the overall uncertainty of the calibrator are analyzed: the conductance fluctuations of the temperature sensor in the absorption cavity and the beam scatter are found to be the most significant error sources. Limited absorptivity of the cavity (0.99998) and the background radiation cause additional uncertainty. The system is controlled by a microcomputer with self-check and autocalibration features.

U2 - 10.1109/19.192347

DO - 10.1109/19.192347

M3 - Article

VL - 38

SP - 558

EP - 564

JO - IEEE Transactions on Instrumentation and Measurement

JF - IEEE Transactions on Instrumentation and Measurement

SN - 0018-9456

IS - 2

ER -