TECH LIBRARY

Chart giving an estimate of the total lumens (lm) for various CCFL diameters and lengths.

An understanding of the history and development of a technology can be a tremendous aid in properly utilizing it for a given application. A brief history and overview is given for the CCFL (Cold Cathode Fluorescent Lamp), also referred to as SMFL (Sub-Miniature Fluorescent Lamp). A description of CCFL electrical discharge lighting devices with typical construction and function is given.

An overview of how to minimize RFI output when considering the use of CCFLs and their associated inverters.

Detailed instructions on how to replace the lighting element of the Microtek 9800XL with JKL CCFL assembly part number BF20325-24B/ASSY/01

Cold Cathode Fluorescent Lamps (CCFLs) 3.0mm - 6.5mm in diameter are commonly used in a variety of backlight configurations for LCD displays; as light sources for scanners and CCD cameras. CCFLs exhibit unique electrical, photometric, and environmental characteristics, which present a challenge for designers. Aspects of diameter and length versus voltage, current and luminance are examined. A basic CCFL drive inverter configuration is given with an examination of a vacuum thermocouple current measurement scheme.

The rated light output of CCFL lamps for design purposes is usually specified at 25°C. The actual output of a given CCFL lamp is, however, significantly affected by the ambient temperature in which it operates. An understanding of the temperature characteristics of CCFL lamps is therefore essential to the correct design of a lamp for a particular application.

An examination of the Cold Cathode Fluorescent Lamp (CCFL) utilized extensively as the light source for LCD displays such as used in laptop computers and other portable devices is reviewed. Discussion includes electrical dynamics in relation to physical dimensions and temperature of the lamps. A general overview of the efficiency of the lamp and inverter system is given. Depletion of mercury from the discharge column influencing light output is attributed to DC operation and temperature. Included is an overview of low-pressure CCFL mercury lamp construction and physics. Normal failure mode is attributed to phosphor degradation.

A brief overview of the UV-C range of ultraviolet CCFLs

A brief overview and diagram of ultraviolet CCFLs

A brief overview of spatial design concerns for applications using CCFLs

Inserted through or atop PC-board, Thru-board and Surface Mount Lamps are well suited for a variety of applications from air controls and instrument clusters requiring a high level of light output to small control switches requiring a small compact light source.

The WWT series of lamps are integral assemblies consisting of a lamp, base and contact

terminals.  The lamp used in the assembly is a high vacuum wire terminal

type.

The installation of JKL's DC/AC inverters is relatively simple, but a few precautions observed during the installation and wiring of the inverters to CCFL's will help to insure a smooth integration into your application. Wiring diagrams for the most common DC/AC inverters are included.

Based LEDs are suitable for new designs but are also suitable for replacing incandescent lamps in existing designs without having to change sockets or mounting schemes. This document includes a list of several popular incandescent subminiature lamps and their LED based lamp equivalents. Care should be taken in choosing the correct LED based lamp to make sure that the LED will illuminate the area the same as the incandescent lamp by having equal viewing angle of the light and intensity.

This glossary of lighting and electronic terms is presented as an aide to the user of JKL's product line of lamps and lighting accessories. Many of the specialized terms used in JKL's applications information, specifications and literature will be defined.

Chart showing a portion of the electromagnetic spectrum & associated wavelengths of light

Charts showing the response rate for the human eye in bright light and in dim light.