The Birth, Death and Rebirth of the Light Bulb

We have looked at light and lighting in long past meetings. But much has happened in the last few years. It is worth reviewing some of the amazing technological, technical and engineering changes which have come about since the first appearance of electric light.

John Wells worked in the Lighting Industry for many years and will be giving us the lowdown on numerous lighting aspects and some key fallacies.

We'll start with the very first electric light. Of course we could go back several thousand years and look at candles, oil lamps, gas lighting and more. But given our focus on engineering, we will start in the 19th century.

Here is a quick summary of the background

* We will be covering carbon arc lamps and the earliest incandescent filament lamps. We will look at the race to earn and exploit patents.

* The Monopolies Commission was convinced that the major lamp suppliers were running cartels and exploiting the public. I will have a good look at that and you will be in for some surprises!

* The introduction of high pressure Mercury and Sodium discharge lighting and the horrid yellow low pressure Sodium lamps used for highway illumination

* The low pressure fluorescent lamp.

* The compact fluorescent lamp introduced by Philips and others

* LED lighting. Low power LEDs have been around since the late '60s.

Today we will be focussing on the LED

The development of cool efficient, long lasting and controllable LED lighting for domestic, commercial and industrial applications has really exploded in the last 10 years

FURTHER STUDY - THE P_N JUNCTION

A ten minute video which explains the P-N junction clearly.