Prototype.

My final idea is to combine the three main elements of testing equipment and the main feature of this device is to be light.
I got some feedback from Morag,

'The challenges I find in the dark (or in low light e.g. in the car in the morning, in a room which isn't well lit at night, when camping etc) are: getting the right amount of blood onto the test strip and putting the right end of the test strip in to the meter. If the screen light is not on it is also very difficult to see the numbers on the screen etc.'

'However if a meter had some way of lighting up, so there is enough light to see the blood going on to the strip and so the screen is visible then a test could be done quickly without too much effort or inconvenience to others.'

From this feedback I decided to focus on a prototype in which to test the different colours of light which would be best at different times of the day.
The four colours that I tested were blue, green, red and amber.

Amber:

Green:

Blue:

Red:

I found that Amber was the best colour for my eyes at different times of the day.