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CCFL
Cold cathode fluorescent lamps have long dominated the market for larger format colour LCD backlights. This is due to the CCFL’s exceptional brightness and full spectral output. CCFLs make power-efficient backlights, but require foam or other special packaging materials in applications where mechanical shock occurs, such as in portable designs. CCFLs tubes have been steadily shrinking in size, with outer diameters now as small as 1.6 mm. The smaller size CCFLs are typically used in PDAs and other portable products using colour display. CCFLs are typically driven by a 500v AC source at a typical current of 5mA. This can be generated by an inverter module requiring a 5 or 12V DC source.
| Pros | Cons |
| White, Red, Green, Blue, Yellow or Purple available |
Require high voltage AC inverter |
| High Brightness < 40,000cd/m2 | Generally 20,000 hours to half life |
| 40,000 hour versions now available |
Electrically noisy |
| Good uniformity > 80% |
Fragile |
| Ideal for medium or large size displays |
Narrow temperature range |
| Customisable | High Power 2-7W typical |
| Down to 50mW power |
> 5mm thickness |
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