22-25 July 2021 Jodrell Bank Observatory

Power of Light

Light for Life: Of course light is all around us and increasingly we are using it to solve many of the world’s problems. Intensive research over the last decade has produced a whole new range of efficient devices that can either generate light or produce electrical power. Remarkably these devices often rely on the interaction of materials with nanometre dimensions (10-9 metres). We will provide demonstrations on how these devices work and how they will impact on our everyday lives, First of all we are making a great deal of use of light generated by lasers and light emitting diodes (LEDs) for monitoring our health – the differing absorption of light by oxygenated and de-oxygenated blood allows us to monitor blood oxygen levels and heart rate providing a window into respiratory efficiency. We will provide hands-on opportunities to show how these measurements are made in practice. Also most importantly at the moment we use 20% of the electricity generated globally for lighting, this figure can be slashed by 50% with the increased use of LED light bulbs. We will demonstrate the vastly different power consumption of incandescent bulbs, compact fluorescent lamps and LED bulbs. We will look inside an LED light bulb to see how blue light and yellow light are combined to make white light and explain why they are so efficient. Pollution can be reduced not only be using less energy but also by generating the power we need by using cleaner sources. One case in particular stands out, it is hoped that we will be able to generate a significant amount of power using solar cells. We will provide hands on demonstrations on how quantum dots can be used to generate clean energy.