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Spectral identification of lighting type and character.

Elvidge CD, Keith DM, Tuttle BT, Baugh KE - Sensors (Basel) (2010)

Bottom Line: Given the high cost that would be associated with building and flying a hyperspectral sensor with detection limits low enough to observe nighttime lights we conclude that it would be more feasible to fly an instrument with a limited number of broad spectral bands in the visible to near infrared.However, the three photoreceptor bands performed poorly in the identification of lighting types when compared to the bands modeled on the Landsat Thematic Mapper.Our conclusion is that it is feasible to identify lighting type and make reasonable estimates of LER and CCT using four or more spectral bands with minimal spectral overlap spanning the 0.4 to 1.0 um region.

View Article: PubMed Central - PubMed

Affiliation: Earth Observation Group, Solar and Terrestrial Division, NOAA National Geophysical Data Center, 325 Broadway, Boulder, CO 80305, USA. chris.elvidge@noaa.gov

ABSTRACT
We investigated the optimal spectral bands for the identification of lighting types and the estimation of four major indices used to measure the efficiency or character of lighting. To accomplish these objectives we collected high-resolution emission spectra (350 to 2,500 nm) for forty-three different lamps, encompassing nine of the major types of lamps used worldwide. The narrow band emission spectra were used to simulate radiances in eight spectral bands including the human eye photoreceptor bands (photopic, scotopic, and "meltopic") plus five spectral bands in the visible and near-infrared modeled on bands flown on the Landsat Thematic Mapper (TM). The high-resolution continuous spectra are superior to the broad band combinations for the identification of lighting type and are the standard for calculation of Luminous Efficacy of Radiation (LER), Correlated Color Temperature (CCT) and Color Rendering Index (CRI). Given the high cost that would be associated with building and flying a hyperspectral sensor with detection limits low enough to observe nighttime lights we conclude that it would be more feasible to fly an instrument with a limited number of broad spectral bands in the visible to near infrared. The best set of broad spectral bands among those tested is blue, green, red and NIR bands modeled on the band set flown on the Landsat Thematic Mapper. This set provides low errors on the identification of lighting types and reasonable estimates of LER and CCT when compared to the other broad band set tested. None of the broad band sets tested could make reasonable estimates of Luminous Efficacy (LE) or CRI. The photopic band proved useful for the estimation of LER. However, the three photoreceptor bands performed poorly in the identification of lighting types when compared to the bands modeled on the Landsat Thematic Mapper. Our conclusion is that it is feasible to identify lighting type and make reasonable estimates of LER and CCT using four or more spectral bands with minimal spectral overlap spanning the 0.4 to 1.0 um region.

No MeSH data available.


Emission spectrum of a high pressure sodium lamp.
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f14-sensors-10-03961: Emission spectrum of a high pressure sodium lamp.

Mentions: High Pressure Sodium Lamps: These are HID lamps containing a sodium-mercury amalgam and trace quantities of inert gas, such as xenon, to assist in the startup. An electric arc passing through the chamber excites the electrons on the sodium and mercury atoms, causing them to glow. These lamps produce a characteristic golden-orange light. Spectra were measured for three high pressure sodium (HPS) lamps. The strongest emission line is from the set of sodium emissions at 819 nm (Figure 14). This emission line is also present in the metal halide lamp spectra. Other strong emission lines occur at 569, 594, 1,140, 595, and 598 nm. There is a dense cluster of strong emission lines from 569 to 616 nm. In addition to the 819 and 1,140 nm lines, there are infrared emission lines at 767, 1,269, 1,846, 2,207, and 2,339 nm. The mean and standard deviation analysis found that the most variable emission line is at 594, followed by the emission lines at 595, 598, 582, 585, 584, 1,140 and 615 nm (Figure 15). Overall, the HPS spectra have less variability than the fluorescent and metal halide lamps.


Spectral identification of lighting type and character.

Elvidge CD, Keith DM, Tuttle BT, Baugh KE - Sensors (Basel) (2010)

Emission spectrum of a high pressure sodium lamp.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3274255&req=5

f14-sensors-10-03961: Emission spectrum of a high pressure sodium lamp.
Mentions: High Pressure Sodium Lamps: These are HID lamps containing a sodium-mercury amalgam and trace quantities of inert gas, such as xenon, to assist in the startup. An electric arc passing through the chamber excites the electrons on the sodium and mercury atoms, causing them to glow. These lamps produce a characteristic golden-orange light. Spectra were measured for three high pressure sodium (HPS) lamps. The strongest emission line is from the set of sodium emissions at 819 nm (Figure 14). This emission line is also present in the metal halide lamp spectra. Other strong emission lines occur at 569, 594, 1,140, 595, and 598 nm. There is a dense cluster of strong emission lines from 569 to 616 nm. In addition to the 819 and 1,140 nm lines, there are infrared emission lines at 767, 1,269, 1,846, 2,207, and 2,339 nm. The mean and standard deviation analysis found that the most variable emission line is at 594, followed by the emission lines at 595, 598, 582, 585, 584, 1,140 and 615 nm (Figure 15). Overall, the HPS spectra have less variability than the fluorescent and metal halide lamps.

Bottom Line: Given the high cost that would be associated with building and flying a hyperspectral sensor with detection limits low enough to observe nighttime lights we conclude that it would be more feasible to fly an instrument with a limited number of broad spectral bands in the visible to near infrared.However, the three photoreceptor bands performed poorly in the identification of lighting types when compared to the bands modeled on the Landsat Thematic Mapper.Our conclusion is that it is feasible to identify lighting type and make reasonable estimates of LER and CCT using four or more spectral bands with minimal spectral overlap spanning the 0.4 to 1.0 um region.

View Article: PubMed Central - PubMed

Affiliation: Earth Observation Group, Solar and Terrestrial Division, NOAA National Geophysical Data Center, 325 Broadway, Boulder, CO 80305, USA. chris.elvidge@noaa.gov

ABSTRACT
We investigated the optimal spectral bands for the identification of lighting types and the estimation of four major indices used to measure the efficiency or character of lighting. To accomplish these objectives we collected high-resolution emission spectra (350 to 2,500 nm) for forty-three different lamps, encompassing nine of the major types of lamps used worldwide. The narrow band emission spectra were used to simulate radiances in eight spectral bands including the human eye photoreceptor bands (photopic, scotopic, and "meltopic") plus five spectral bands in the visible and near-infrared modeled on bands flown on the Landsat Thematic Mapper (TM). The high-resolution continuous spectra are superior to the broad band combinations for the identification of lighting type and are the standard for calculation of Luminous Efficacy of Radiation (LER), Correlated Color Temperature (CCT) and Color Rendering Index (CRI). Given the high cost that would be associated with building and flying a hyperspectral sensor with detection limits low enough to observe nighttime lights we conclude that it would be more feasible to fly an instrument with a limited number of broad spectral bands in the visible to near infrared. The best set of broad spectral bands among those tested is blue, green, red and NIR bands modeled on the band set flown on the Landsat Thematic Mapper. This set provides low errors on the identification of lighting types and reasonable estimates of LER and CCT when compared to the other broad band set tested. None of the broad band sets tested could make reasonable estimates of Luminous Efficacy (LE) or CRI. The photopic band proved useful for the estimation of LER. However, the three photoreceptor bands performed poorly in the identification of lighting types when compared to the bands modeled on the Landsat Thematic Mapper. Our conclusion is that it is feasible to identify lighting type and make reasonable estimates of LER and CCT using four or more spectral bands with minimal spectral overlap spanning the 0.4 to 1.0 um region.

No MeSH data available.