I got a ZTE Blade phone (Android) today and I cannot turn off adaptive brightness. I can go into the settings and adjust the actual brightness, but there is no Auto-Dim, Auto-Adjust, etc option. There is literally only a slider and that's all. After running a health check with verizon, it said that screen brightness was set to auto, but it provided no means of changing that. Before you answer, please do not tell me to Navigate>Display>Brightness or edit the battery settings. I have already done that and the option for auto adjustment is just not there.
"ZTE Blade" doesn't tell anything. I Google searched it and there are several models that is under that name.
One of the results brought up a pdf with how to adjust adaptive brightness. Without giving a specific model, we can't help you. It's a bit like saying you have a Samsung Galaxy when there are lots of phones in that family.