Bench Talk

Many people yearn for the sunny days of summer. The frequencies of sunlight have been shown to have health benefits, and the lack of sunlight causes a range of problems, from vitamin deficiency to Seasonal Affective Disorder (SAD). The UK’s health department is now even recommending vitamin D for everyone during the winter months.

A team of engineers in Germany is addressing the challenge of getting enough light with a new, app-controlled intelligent lamp. The HEAVN One is a desk lamp, a daylight lamp and a room illuminator, all in one. It takes the well-established idea of the health benefits of light, and expands it in three different ways.

Through an array of individually controlled LEDs, it can provide a blast of blue light that acts like ‘visual caffeine’ to give the body a boost for higher productivity and focus. This is triggered by a ‘caffeine’ button to give the boost, which gradually and automatically fades back to the appropriate balance for the time of day.

At the same time, the balance of the different frequencies in the light is automatically varied throughout the day to replicate the sun itself. So there will be more blue light in the morning, fading to more red light in the evening to help the body settle down into a natural pattern for sleep. While the lamp can give a ‘caffeine’ boost during the day, by the evening it automatically provides the whole room with warm, ambient light. This delivers enough illumination to read a book and unwind, but as the light lacks the blue frequencies, the body can produce the natural hormone melatonin, necessary to prepare it for sleep

Figure 1: HEAVN night function

The third element is to replicate the profile of light in different parts of the world via an app. A smartphone connects to the HEAVN lamp via Bluetooth Low Energy so the user can choose whether to have light from California, Barcelona or even Stockholm.

The team has worked with leading researchers at the Ludwig Maximilian University in Munich and at UC Berkeley to bring all of the advanced technology together to create the electronics around the lamp and the app that brings a significantly higher level of control to the user. With support from the Technical University in Munich, the European Union and the German Ministry of Economics, the team has designed the LED array, power management sub-system and sophisticated controller.

This is combined with the nRF51822 Bluetooth Low Energy 2.4GHz Wireless System on Chip from Nordic Semiconductor to connect to a user’s smartphone. Based around a 32bit ARM Cortex M0 processor with 256kB of flash memory and 16kB of RAM, the chip includes an embedded 2.4GHz transceiver for the Bluetooth low energy link and a wide range of analogue and digital peripherals and power management to simplify the RF design.

The development of the user control and interface on the phone is a key differentiator. Being able to provide the different types of sunlight and the caffeine boost to help the improve the user’s day delivers a new type of experience, enabled by the latest technology.