Light sources its advantages & disadvantages
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This document discusses different types of light sources including natural daylight and electric light. It provides details on incandescent lamps like tungsten and tungsten halogen, as well as discharge lamps including fluorescent, compact fluorescent, mercury vapor, sodium vapor, and induction lamps. The advantages and disadvantages of each type are outlined relating to properties like luminous efficacy, color rendering, lamp life, and applications.
Light sources its advantages & disadvantages
- 1. LIGHT SOURCES ITSLIGHT SOURCES ITS ADVANTAGES &ADVANTAGES & DISADVANTAGESDISADVANTAGES OPTOM FASLU MUHAMMED
- 2. LIGHT SOURCESLIGHT SOURCES Natural day lightNatural day light Electric light (artificial)Electric light (artificial)
- 3. NATURAL DAY LIGHTNATURAL DAY LIGHT Free of chargeFree of charge Varies in quantity, colour, directions (timeVaries in quantity, colour, directions (time of day, weather condition)of day, weather condition)
- 4. ELECTRIC LIGHTELECTRIC LIGHT It is constant & provided there is a supplyIt is constant & provided there is a supply of electricityof electricity
- 5. LUMINOUS EFFICACYLUMINOUS EFFICACY Amount of light given by a lamp for eachAmount of light given by a lamp for each watt of power consumed & is measured inwatt of power consumed & is measured in (lumens/watt)(lumens/watt) Cannot normally operated directly fromCannot normally operated directly from mains electricity supplymains electricity supply
- 6. COLOUR PROPERTIESCOLOUR PROPERTIES Related to the spectral composition of theRelated to the spectral composition of the emissionemission Include -colour renderingInclude -colour rendering -colour appearance-colour appearance
- 7. COLOUR RENDERINGCOLOUR RENDERING Describes the appearance of coloursDescribes the appearance of colours
- 9. LAMP LIFELAMP LIFE The term ‘life’ of an electric lamp can haveThe term ‘life’ of an electric lamp can have two different meaningstwo different meanings -The time after which the lamp ceases to-The time after which the lamp ceases to operateoperate -The time after which the light output is so-The time after which the light output is so reducedreduced
- 10. Lamps - incandescentLamps - incandescent - discharge lamps- discharge lamps
- 11. INCANDESCENTINCANDESCENT TungstenTungsten Tungsten halogenTungsten halogen
- 12. TUNGSTENTUNGSTEN Operate by heating a tungsten filamentOperate by heating a tungsten filament Filled with an inert gasFilled with an inert gas
- 13. ADVADV Immediate full light outputImmediate full light output Lamps operate in all positionLamps operate in all position Easy to control the lampEasy to control the lamp
- 14. DIS ADVDIS ADV Short lifeShort life Sensitive to vibrationSensitive to vibration Not used for colour matchingNot used for colour matching
- 15. TUNGSTEN HALOGENTUNGSTEN HALOGEN Filament lampFilament lamp Filled with halogen compound gasFilled with halogen compound gas
- 16. ADVADV Higher luminous efficacyHigher luminous efficacy Lamp life longerLamp life longer Small & compact ideal for optometricSmall & compact ideal for optometric instrumentsinstruments
- 17. DIS ADVDIS ADV Surface of the bulb is liable to deteriorateSurface of the bulb is liable to deteriorate if touched with the fingersif touched with the fingers
- 18. DISCHARGE LAMPSDISCHARGE LAMPS Utilize the ionization of gas to produceUtilize the ionization of gas to produce lightlight - fluorescent (low pressure mercury)- fluorescent (low pressure mercury) lampslamps -compact fluorescent lamps-compact fluorescent lamps -high pressure mercury lamps-high pressure mercury lamps -low pressure sodium lamps-low pressure sodium lamps -high pressure sodium lamps-high pressure sodium lamps -inductions lamps-inductions lamps
- 19. FLUORESCENT LAMPFLUORESCENT LAMP Known as tubular fluorescent lampKnown as tubular fluorescent lamp Produces radiation in the visibleProduces radiation in the visible
- 20. COMPACT FLUORESCENT LAMPCOMPACT FLUORESCENT LAMP Smaller versions of long distanceSmaller versions of long distance tubetube
- 21. HIGH PRESSURE MERCURYHIGH PRESSURE MERCURY LAMPSLAMPS Consists of quartz arc tubeConsists of quartz arc tube Used in industrial & road lightiningUsed in industrial & road lightining
- 22. LOW PRESSURE SODIAM LAMPLOW PRESSURE SODIAM LAMP Radiation emitted from these lamp isRadiation emitted from these lamp is monochromaticmonochromatic Used for street lighteningUsed for street lightening
- 23. HIGH PRESSURE SODIUM LAMPHIGH PRESSURE SODIUM LAMP Emit more continuous spectrumEmit more continuous spectrum Have better colour propertiesHave better colour properties Used in road lightning , sports hallUsed in road lightning , sports hall
- 24. INDUCTION LAMPSINDUCTION LAMPS New typeNew type Known as eletrodeless lampKnown as eletrodeless lamp
- 25. ADV OF DISCHARGE LAMPSADV OF DISCHARGE LAMPS Lamp life longerLamp life longer Excellent colour rendering propertiesExcellent colour rendering properties
- 26. DIS ADVDIS ADV FlickerFlicker Stroboscopic effectsStroboscopic effects