I have had the same problem with the two pumps I have been using over the past six years, Animas Vibe and now Omnipod.
I have complained several times to Ypsomed (Omnipod supplier in the UK) but have had no satisfactory responses.
I spend a considerable amount of time outdoors and find it extremely difficult to read the screen in bright conditions.
I am now about to change to the Cellnovo system and the good news is that this screen is visible in bright light, so I am voting with my feet and ditching Omnipod, also I believe Cellnovo costings are lower than Omnipod.
Had I not been about to change I was seriously considering putting a complaint to the MHRA, the UK body which regulates healthcare devices as I believe this is a very serious issue which could lead to serious harm to a patient if blood glucose results are incorrectly read or inappropriate boluses are administered due to the inability to see the screen in bright light.
surely it is more important to be able to read a medical device screen in sunshine rather than read a novel on a Kindle or similar device?