Maximum of LCD computer monitors have a maximum brightness of around 300 nits or 300 candelas per square meter. Higher-end LCDs are capable of 400 nits; however this still may not be sufficient when working outdoors in direct sunlight conditions. Some professional-grade screens are capable of producing 1000 nits or more.
Here are the steps to increase the monitor brightness:
1). Launch the main control panel for your graphics accelerator by right-clicking the manufacturer icon located on the taskbar, then select "Properties."
2). Click on the "Video Settings" tab or button and then select the "Color Control" tab.
3). Adjust the various slider bars to modify not only maximum contrast and brightness, but also color saturation and hue. This is especially usefull if your monitor has a specific tint, or tendency to lean toward a specific color.
4). Click on the drop-down menu beside "Preset Profiles" (if equipped) and choose an option from the available list. For example, 'Brighten Movie" will automatically increase brightness when a movie is played. Click "OK" on the open display properties windows to save settings.