Selective yellow is a colour for automotive lamps, particularly headlamps and other road-illumination lamps such as fog lamps.[1] Under ECE regulations, headlamps were formerly permitted to be either white or selective yellow—in France, selective yellow was mandatory for all vehicles' road-illumination lamps until 1993.
Both the internationalized European ECE Regulation 19[2] and North American SAE standard J583[3] permit selective yellow front fog lamps. Meanwhile, ECE Regulation 48 (enforced 08 October 2016) requires new vehicles to be equipped with headlamps emitting white light.[4] However, selective yellow headlamps remain permitted throughout Europe on vehicles already so equipped, as well as in non-European locales such as Japan[5] and New Zealand.[6]
The intent of selective yellow is to improve vision by removing short, blue to violetwavelengths from the projected light. These wavelengths are difficult for the human visual system to process properly, and they cause perceived dazzle and glare effects in rain, fog and snow.[7] Removing the blue-violet portion of a lamp's output to obtain selective yellow light can entail filter losses of around 15%,[8] though the effect of this reduction is said to be mitigated or countervailed by the increased visual acuity available with yellow rather than white light in bad weather.[7]
A research experiment done in the UK in 1968 using tungsten (non-halogen) lamps found that visual acuity is about 3% better with selective yellow headlamps than with white ones of equal intensity.[9] Research done in the Netherlands in 1976 concluded that yellow and white headlamps are equivalent as regards traffic safety, though yellow light causes less discomfort glare than white light.[10] Researchers note that tungsten filament lamps emit only a small amount of the blue light blocked by a selective-yellow filter,[9] so such filtration makes only a small difference in the characteristics of the light output,[7] and suggest that headlamps using newer kinds of sources such as metal halide (HID) bulbs may, through filtration, give off less visually distracting light while still having greater light output than halogen ones.[7]
Formal definitionedit
The UNECE Regulations formally define selective yellow in terms of the CIE 1931 colour space as follows:
Limit towards red
Limit towards green
Limit towards white
Limit towards spectral value
For front fog lamps, the limit towards white is extended:
Limit towards white
The entirety of the basic selective yellow definition lies outside the gamut of the sRGB colour space—such a pure yellow cannot be represented using RGB primaries. The colour swatch above is a desaturated approximation, created by taking the centroid of the standard selective yellow definition at (0.502, 0.477) and moving it towards the D65 white point, until it meets the sRGB gamut triangle at (0.478, 0.458).
^ECE Regulation 48: Uniform Provisions Concerning the Approval of Vehicles with Regard to the Installation of Lighting and Light-Signalling Devices
^Japanese Industrial Standard JIS D-5500 2007-08-15 at the Wayback MachineAutomobile Parts--Lighting and Light Signaling Devices p. 5, sec. 4.4.2, table #4
^ abcdBullough, John; Mark S. Rea (2001). (PDF). SAE Technical Paper Series. 1. doi:10.4271/2001-01-0320. Archived from the original (PDF) on 2006-02-23. Retrieved 2010-01-27.
^Devaux, P. (1970). "State-of-the-Art-Signaling and Lighting". State-of-the-Art Signaling and Lighting (Report). SAE Technical Paper Series. Vol. 1. Society of Automotive Engineers. doi:10.4271/700386. 700386.
^ abChristie, A.W.; Ashwood, J.E.; Symons, R.D.H. (1968). (PDF) (Report). UK Ministry of Transport Road Research Laboratory. LR 156. Archived from the original (PDF) on 2018-07-29. Retrieved 29 July 2018.
^White or Yellow Light for Vehicle Head-Lamps? (Report). Dutch Institute for Road Safety Research. 1976. 1976-2E. Retrieved 29 July 2018.
External linksedit
Wikimedia Commons has media related to Selective yellow headlamps.
January 01, 1970
selective, yellow, colour, automotive, lamps, particularly, headlamps, other, road, illumination, lamps, such, lamps, under, regulations, headlamps, were, formerly, permitted, either, white, selective, yellow, france, selective, yellow, mandatory, vehicles, ro. Selective yellow is a colour for automotive lamps particularly headlamps and other road illumination lamps such as fog lamps 1 Under ECE regulations headlamps were formerly permitted to be either white or selective yellow in France selective yellow was mandatory for all vehicles road illumination lamps until 1993 Selective yellow approximation Colour coordinatesHex triplet FFBA00sRGBB r g b 255 186 0 HSV h s v 44 100 100 CIELChuv L C h 80 100 55 SourceCIECDISCC NBS descriptorStrong orange yellowB Normalized to 0 255 byte One of the first optic headlamp lenses the Corning Conaphore made of selective yellow Noviol glass Contents 1 Colour 2 Formal definition 3 References 4 External linksColour editBoth the internationalized European ECE Regulation 19 2 and North American SAE standard J583 3 permit selective yellow front fog lamps Meanwhile ECE Regulation 48 enforced 08 October 2016 requires new vehicles to be equipped with headlamps emitting white light 4 However selective yellow headlamps remain permitted throughout Europe on vehicles already so equipped as well as in non European locales such as Japan 5 and New Zealand 6 The intent of selective yellow is to improve vision by removing short blue to violet wavelengths from the projected light These wavelengths are difficult for the human visual system to process properly and they cause perceived dazzle and glare effects in rain fog and snow 7 Removing the blue violet portion of a lamp s output to obtain selective yellow light can entail filter losses of around 15 8 though the effect of this reduction is said to be mitigated or countervailed by the increased visual acuity available with yellow rather than white light in bad weather 7 A research experiment done in the UK in 1968 using tungsten non halogen lamps found that visual acuity is about 3 better with selective yellow headlamps than with white ones of equal intensity 9 Research done in the Netherlands in 1976 concluded that yellow and white headlamps are equivalent as regards traffic safety though yellow light causes less discomfort glare than white light 10 Researchers note that tungsten filament lamps emit only a small amount of the blue light blocked by a selective yellow filter 9 so such filtration makes only a small difference in the characteristics of the light output 7 and suggest that headlamps using newer kinds of sources such as metal halide HID bulbs may through filtration give off less visually distracting light while still having greater light output than halogen ones 7 Formal definition editThe UNECE Regulations formally define selective yellow in terms of the CIE 1931 colour space as follows Limit towards red y 0 138 0 580 x displaystyle y geq 0 138 0 580x nbsp Limit towards green y 1 290 x 0 100 displaystyle y leq 1 290x 0 100 nbsp Limit towards white y 0 966 x displaystyle y geq 0 966 x nbsp Limit towards spectral value y 0 992 x displaystyle y leq 0 992 x nbsp For front fog lamps the limit towards white is extended Limit towards white y 0 940 x displaystyle y geq 0 940 x nbsp y 0 440 displaystyle y geq 0 440 nbsp The entirety of the basic selective yellow definition lies outside the gamut of the sRGB colour space such a pure yellow cannot be represented using RGB primaries The colour swatch above is a desaturated approximation created by taking the centroid of the standard selective yellow definition at 0 502 0 477 and moving it towards the D65 white point until it meets the sRGB gamut triangle at 0 478 0 458 nbsp Porsche 911 with selective yellow lights nbsp Selective yellow foglights nbsp The beam produced by selective yellow lightsReferences edit UNECE ECE Regulation 19 Uniform Provisions Concerning the Approval of Power Driven Vehicle Front Fog Lamps SAE Standard J583 Front Fog Lamp ECE Regulation 48 Uniform Provisions Concerning the Approval of Vehicles with Regard to the Installation of Lighting and Light Signalling Devices Japanese Industrial Standard JIS D 5500 Archived 2007 08 15 at the Wayback Machine Automobile Parts Lighting and Light Signaling Devices p 5 sec 4 4 2 table 4 New Zealand Vehicle Inspection Requirement Manual p 4 1 2 a b c d Bullough John Mark S Rea 2001 Driving in Snow Effect of Headlamp Color at Mesopic and Photopic Light Levels PDF SAE Technical Paper Series 1 doi 10 4271 2001 01 0320 Archived from the original PDF on 2006 02 23 Retrieved 2010 01 27 Devaux P 1970 State of the Art Signaling and Lighting State of the Art Signaling and Lighting Report SAE Technical Paper Series Vol 1 Society of Automotive Engineers doi 10 4271 700386 700386 a b Christie A W Ashwood J E Symons R D H 1968 Visual Acuity in Yellow Headlights PDF Report UK Ministry of Transport Road Research Laboratory LR 156 Archived from the original PDF on 2018 07 29 Retrieved 29 July 2018 White or Yellow Light for Vehicle Head Lamps Report Dutch Institute for Road Safety Research 1976 1976 2E Retrieved 29 July 2018 External links edit nbsp Wikimedia Commons has media related to Selective yellow headlamps Retrieved from https en wikipedia org w index php title Selective yellow amp oldid 1223178068, wikipedia, wiki, book, books, library,
