I have found some published s/p ratios of some light sources to be incorrect. Many incorrect figures appear to me to be incorrectly low ones stated by proponents of one or two particular light source technologies competing against others whose s/p figures were incorrectly stated.
In addition, I have found lack of published s/p ratios of some light sources where this is of interest.
As a result, I have added a chart of what I believe to be correct s/p ratios of many light sources, with sources of data/"data". Much of this data is from questionable to low-traceability measurements, from measurements that I can trace but requiring adjustments whose properness I was unable to "properly" measure, from theoretical calculations of some items that are easy to at least somewhat fairly easy to reconstruct, and from 3 "reconstructions" of high pressure mercury vapor power distribution that I hope I did a good job of pulling out of my hat. Few of these figures are from spectral data that I have both actually seen to extent of knowing whose spectrometer was used and found to not require "adjustments" for clipping and noise.
Daylight Light Sources
Incandescent Light Sources
Fluorescent Lamps
HID and Discharge Lamps
LED Light Sources
Monochromatic Visible Lasers
Light Source s/p ratio source / determination
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DAYLIGHT SOURCES
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Typical "north light" 2.59 Calculated s/p of 7500K blackbody
Typical overcast sky 2.36 Calculated s/p of 6000K blackbody
Typical sunlight + sky 2.26 Calculated s/p of 5500K blackbody
Typical direct sunlight
plus partial sky 2.1 Calculated s/p of 4800K blackbody
Typical isolated direct
sunlight 1.99 Calculated s/p of 4400K blackbody
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INCANDESCENT SOURCES
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Candle Flame .88 Calculated s/p of 1900K blackbody
Incandescent Nightlight 1.12 Calculated s/p of 2300K blackbody
60W 130V 5000hr @120V 1.29 Calculated s/p of 2600K blackbody
60W 120V 1000 hour A19 1.39 Calculated s/p of 2800K blackbody
100W 120V 750 hour A19 1.42 Calculated s/p of 2875K blackbody
Most halogen lamps 1.46 Calculated s/p of 2950K blackbody
50W 12V and 500W 120V
halogens 1.50 Calculated s/p of 3050K blackbody
Halogen headlight,
low beam 1.52 Calculated s/p of 3100K blackbody
Halogen headlight,
high beam 1.57 Calculated s/p of 3200K blackbody
Short life photo
lamps, 3400K 1.65 Calculated s/p of 3400K blackbody
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FLUORESCENT LAMPS
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"Old Tech" Warm White 1.00 Berman, 1992 (Note 1)
"Old Tech" Cool White 1.48 Rensellaer Lighting Research Ctr
"Old Tech" Cool White 1.47 My calculation from an adjusted
spectrometer-obtained SPD (Note 4)
"Old Tech" Daylight 2.22 Berman, 1992 (Note 1)
2700K CFL 1.13 My calculation from an adjusted
spectrometer-obtained SPD (Note 4)
T8 triphosphor 730/SP30 1.3 GE fluorescent lamp catalog (Note 7)
T8 triphosphor 830/SPX30 1.3 GE fluorescent lamp catalog (Note 7)
T8 triphosphor 735/SP35 1.4 GE fluorescent lamp catalog (Note 7)
T8 triphosphor 830/SPX35 1.5 GE fluorescent lamp catalog (Note 7)
T8 triphosphor 741/SP41 1.6 GE fluorescent lamp catalog (Note 7)
T8 triphosphor 841/SPX41 1.8 GE fluorescent lamp catalog (Note 7)
T8 triphosphor 750/SP50 1.9 GE fluorescent lamp catalog (Note 7)
T8 triphosphor 850/SPX50 2.0 GE fluorescent lamp catalog (Note 7)
T8 triphosphor 765/SP65 2.1 GE fluorescent lamp catalog (Note 7)
T8 triphosphor 865/SPX65 2.3 GE fluorescent lamp catalog (Note 7)
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HID and DISCHARGE LAMPS
-----------------------
Low Pressure Sodium .23 s/p ratio of 589 nm
(Same as Berman, Note 1)
High Pressure Sodium, 35W .4 Berman, 1992 (Note 1)
High Pressure Sodium, 50W .62 Berman, 1992 (Note 1)
High Pressure Sodium, 250W .63 Rensellaer Lighting Research Ctr (Note 2)
High Pressure Sodium, 400W .66 Rensellaer Lighting Research Ctr (Note 2)
White HPS, 50W 1.14 Berman, 1992 (Note 1)
Metal Halide, clear, 175W 1.51 Rensellaer Lighting Research Ctr (Note 2)
Metal Halide, clear, 400W 1.57 Rensellaer Lighting Research Ctr (Note 2)
Metal Halide, 400W coated 1.49 Rensellaer Lighting Research Ctr (Note 2)
(All above MH likely Na-Sc)
Xe-M.H. 4200K car HID 1.61 Rensellaer Lighting Research Ctr (Note 2)
H.P. Mercury, 175W clear 1.26 My calculation using a
"reconstructed" SPD (Note 6)
(I question the .8 figure for "clear mercury" from Berman Note 1)
H.P. Mercury, 175W clear My calculation using the above
with yellow filter .89 "reconstructed" SPD with <500 nm
removed (Note 6)
H.P. Mercury, 175W DX 1.08 My calculation using a
"Deluxe White", new condition "reconstructed" SPD (Note 6)
H.P. Mercury, 400W clear 1.33 Rensellaer Lighting Research Ctr (Note 2)
H.P. Mercury, 400W coated 1.09 Rensellaer Lighting Research Ctr (Note 2)
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LED SOURCES:
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Older white LEDs, ~6000K, Calculation from a spectrometer-
blue peak ~465 nm, obtained SPD of a Nichia
CRI 75-plus 2.3 NSPWF50DS (Note 3)
White LEDs, ~6000K, Calculation from a spectrometer-
blue peak ~455 nm, obtained SPD of a Lumileds
CRI ~70-75 2.05 Luxeon III (Note 3)
Recent white LEDs, ~5000K, Calculation from a spectrometer-
blue peak ~445 nm, obtained SPD of a Nichia
CRI in the 60's 1.7 NSPWR70CSS-K1 (Note 3)
Red LED, InGaAlP Calculation from adjusted spectrometer-
(635-637 nm peak, obtained SPDs of a red Lumileds
626-627 nm dominant) .044 Luxeon, and Nichia NSPR510CS (Note 5)
Red LED, GaAlAsP Calculation from an adjusted spectrometer-
(660 nm peak, obtained SPD of a Panasonic
low 640's nm dominant) .019 red LED of this type (Note 5)
GaAsAlP red LED filtered Calculation from an adjusted spectrometer-
by Wratten 92 or Schott obtained SPD of above red LED
RG-630 deep red filter .015 with Wratten 92 filter (Note 5)
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MONOCHROMATIC VISIBLE LASERS:
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405 nm violet diode laser 9.9 s/p of 405 nm using 1988
photopic function
441.6 nm HeCd laser 22.16 s/p of 442 nm using 1988
photopic function
458 nm deep blue DPSS 24.1 s/p of 458 nm using 1988
photopic function
473 nm turquoise blue DPSS 17.0 s/p of 473 nm
488 nm cyan argon laser
when single-wavelength 11.5 s/p of 488 nm
532 nm common green laser 2.2 s/p of 532 nm
543.5 nm green HeNe laser 1.51 s/p of 543.5 nm (interpolated)
593.5 nm "yellow" DPSS .181 s/p of 593.5 nm (interpolated)
632.8 nm red He-Ne laser .028 s/p of 632.8 nm (interpolated)
650 nm common diode laser .016 s/p of 650 nm
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Note 1: S/p ratio figures referring Berman, 1992:
Note 2: S/p ratio figures referring to Rensellaer Lighting Research Ctr:
They appear in:
http://www.lrc.rpi.edu/programs/solidstate/pdf/euroLED2008.pdf
Note 3: S/p ratios of these white LEDs was calculated from data from a StellarNet spectrometer, with no adjustments other than the spectrometer software's calibration data for achieving flat spectral response. Calculations used all wavelengths 380 to 780 nm in .5 nm increments, using the 1988 photopic function.
Note 4: S/p ratios of these fluorescent lamps was determined as above in Note 3, except the spectral data files produced by the spectrometer software were adjusted afterwards. The strongest two spectral lines were clipped by the spectrometer or its software. Since the spectrometer is not mine and I was not able to get re-takes, these spectral lines were manually increased in intensity until chromaticity appeared reasonable to me.
Note 5: S/p ratios of these red LEDs was determined as above in Note 3, except the spectral data files produced by the spectrometer software were adjusted afterwards. In wavelength ranges where the data was mainly or effectively exclusively upward spikes of spectrometer noise, the data was manually reduced to zero. After that, the "tails" of the LED's spectrum were manually extrapolated as exponential functions of wavelength, outward in both directions until insignificant, varying exponentially with wavelength at the same rate, as best as can be estimated, as the portions of the "tails" that outweighed the spectrometer noise. Less care was taken at longer essentially infrared wavelengths for this adjustment.
Note 6: These "reconstructed" spectral power distributions of high pressure mercury vapor lamps are "reconstructed" into a file type that I can analyze from 380 to 760 nm from how I remember high pressure mercury vapor spectra. These are adjusted to make chromaticity and color rendition effects making sense. These are not actual measurements and they are "merely out of my hat".
Note 7: These figures for GE triphosphor T8 fluorescent lamps are from a GE fluorescent lamp catalog that I found via web search at:
http://www.topbulb.com/find/Catalogs/GE_Fluorescent.pdf
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