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Home , Xenon arc lamp

Compact Fluorescent Lamps (CFL)

CFLs are effectively a small coiled version of the linear fluorescent tube Most modern CFLs are integrated, ie they contain the ballast internally

A good reference on modern CFL design http://www.eetimes.com/design/power-management-design/4010360/How-compact-fluorescent- lamps-work-and-how-to-dim-them http://en.wikipedia.org/wiki/Compact_fluorescent_lamp

http://www.eetimes.com/design/power-management-design/4010360/How-compact-fluorescent-lamps-work-and-how-to-dim-them http://www.eetimes.com/design/power-management-design/4010360/How-compact-fluorescent-lamps-work-and-how-to-dim-them See extras section on website for full application note AN99065 http://www.ecosmartelectricians.com.au/

CFLs contain between 1 and 5mg of mercury Linear tubes contain up to 12mg, usually less (2mg) http://www.tradevv.com/chinasuppliers/vdeen08_p_3e591/china-G9-halogen-bulb-halogen-lamp.html Halogen lamps

They have a filament similar to an incandescent. The difference is they have a small amount of halogen gas in with the inert gas. An incandescent lamp could have greater efficacy if run at a higher temperature

The filament would evaporate faster and blacken the

Introducing a halogen into the inert gas causes evaporated tungsten to bond with the halogen producing a halide

When the halide approaches the hot filament the tungsten is released to the filament and the halogen is free to collect another tungsten atom The halogen cycle

http://www.lamptech.co.uk/Movies/Halogen%20Cycle.WMV At higher filament temperature the colour temperature is increased

More UV is produced

Need appropriate glass bulb and/or filters to stop UV

Need high temperature glass to handle extra temperature

Eventually suffer from filament thinning

http://en.wikipedia.org/wiki/File:TungstenFilamentHalogenH1Lamp.JPG Safety http://en.wikipedia.org/wiki/File:Wolfram-Halogengl%C3%BChlampe.png

A halogen bulb can have wall temperatures up to 1000°C

Dangerous for humans and a fire risk

Can insulate bulb in evacuated second glass bulb Supply voltage

Light output α V 3

Efficacy α V 1.3

Lifetime α V −14 http://www.ecosmartelectricians.com.au/ High Intensity Discharge (HID)

Has an arc between tungsten electrodes A gas and metal salts are present inside the bulb After the arc strikes the metal salts are formed into a plasma HID types

Mercury vapour Metal Halide Sodium vapour Mercury vapour

Quartz arc tube inside glass bulb

http://ioannis.virtualcomposer2000.com/spectroscope/mercurylamp.html These lamps need a ballast as they are negative resistance

Pressure in the arc tube rises up to 10 atmospheres (1000 KPa) and temperature of 1600°C

The arc cannot be restruck till the pressure drops

http://ioannis.virtualcomposer2000.com/spectroscope/mercurylamp.html The phosphor coating can improve the CRI and colour temperature

No coating

Phosphor coating see http://ioannis.virtualcomposer2000.com/spectroscope/amici.html for wide range of lamp spectras Metal Halide

Similar to mercury HID but will also contain iodides or bromides of scandium, sodium, thallium or indium in an amalgam with the mercury

http://en.wikipedia.org/wiki/File:Closeup_Metal_Halide_Lamp.jpg Pressures can be even higher (up to 50 atm, 5000 KPa)

Temperatures also even higher (3000°C)

Bulbs can explode at these extreme temperatures and pressures

Only some bulbs are suitable for use in open fittings

https://secure.ge-lightingsystems.com/gels01/r2/productcentral/htmls/Indoor_image.html Metal Halide

http://ioannis.virtualcomposer2000.com/spectroscope/amici.html Low Pressure Sodium http://www.lamptech.co.uk/Documents/SO1%20Introduction.htm

The low pressure sodium (LPS) often called the Sodium Oxide (SOX) lamp

Neon and argon gas in the tube is initially used like a normal

When the sodium vaporises the lamp starts to give off large amounts of light The SOX lamp is the most efficient lamp (Efficacy 200 lm/W) It produces monochromatic light at 589.3 nm Close to the maximum sensitivity of the eye Very poor CRI http://www.lamptech.co.uk/Documents/SO1%20Introduction.htm No mercury

http://en.wikipedia.org/wiki/File:LPS_Lamp_35W_running.jpg High Pressure Sodium They contain an amalgam of metallic sodium and mercury

The arc tube is commonly aluminium oxide

Often Xenon is used as a starter gas http://www.bikudo.com/product_search/details/83245/high_pressure_sodium_lamp.html http://en.wikipedia.org/wiki/File:High_pressure_sodium_lamp.svg http://en.wikipedia.org/wiki/File:High_Pressure_Sodium_Lamp_Spectrum.jpg Xenon Often used as a light source in large projection systems

http://en.wikipedia.org/wiki/File:Xenon_short_arc_1.jpg Very high wattage lamps available (over 10kW)

Electrodes often water cooled

Can be xenon only or xenon mercury

Can generate large amounts of UV which can generate

Light produced has a similar spectra to daylight http://zeiss-campus.magnet.fsu.edu/articles/lightsources/xenonarc.html http://www.ecosmartelectricians.com.au/starter-kit/d01_28.html HID ballast

See extras section for document on HID ballasts

Power Electronics Technology | July 2010, www.powerelectronics.com Power Electronics Technology | July 2010, www.powerelectronics.com LED The new technology to take over Already light of choice for automotive, Traffic lights, etc. Already exceeded performance of other light sources Further advances to improve performance and reduce cost. http://en.wikipedia.org/wiki/File:PnJunction-LED-E.PNG RGB leds

http://www.dinodirect.com/3v-12v-10w-cree-mc-e-rgbw-4-chip-led-emitter-20mm-base.html

http://en.wikipedia.org/wiki/File:Red-YellowGreen-Blue_LED_spectra.png Phospor LEDs http://www.mt-berlin.com/frames_cryst/descriptions/led_phosphors.htm

http://en.wikipedia.org/wiki/File:White_LED.png • 12 Watts • Equivalent to 60W BR30 • 50 lumens per Watt • 600 lumens • 25 and 50 Degree Beam Angles • 94 CRI • 2700K • Designed to last 50,000 hours

http://www.creeledlighting.com/products/Lamps/LBR-30.aspx New advances with outputs of 1525 lumens

Efficacy of 200 lm/W Retrofit