Most of us are used to our smartphone screens becoming brighter or dimmer by themselves. This adaptive brightness feature helps to conserve energy and extend the device's battery life.

It also ensures that the screen is readable in different environments. Increasing the screen brightness compensates for bright sunlight when used outdoors, while a dimmer screen is more comfortable on the eyes when viewing in the dark.

BenQ has put this feature into its EW2770QZ Eye-Care monitor. Like your smartphone, this 27-inch monitor has an ambient light sensor below its bottom bezel that detects ambient light levels and automatically adjusts the screen brightness and colour temperature.

It is the first monitor I have tried with an ambient light sensor, which seems a rarity in the industry.

In my testing, this feature, dubbed Brightness Intelligence Plus, worked subtly to tweak the brightness without affecting the vibrancy of colours.

To reduce eye discomfort, there is also an option to make the screen look warmer gradually over time after continuous usage.

You know it is working when a logo with an eye appears momentarily on the screen.

However, it is disabled for certain monitor profiles, like sRGB or Rec.709, where it is important to display accurate colours.

In addition, the BenQ comes with a blue-light filter that reduces the amount of blue light emitted by the monitor. Blue light has been shown to increase your body's alertness, which may be counter-productive when it is close to your bedtime.

There is also a feature called Smart Focus. However, I am not convinced of its usefulness. This feature keeps a rectangular portion of the screen lit while dimming the areas outside. BenQ says it helps you to focus on something, like a video playing in a browser window. But adjusting the size and position of the focus zone is tedious, especially as it is a hassle to navigate the monitor's on-screen display (OSD), which you have to use to adjust the Smart Focus settings.

Unlike other monitors which offer a joystick for navigation, BenQ uses buttons located at its rear for its OSD. And the only shortcuts are for changing the input source and the preset profiles.

Most of the settings are available via the Menu option, where it is easy to hit a wrong button.

I was disappointed that it lacks any kind of adjustment. Its stand has a fixed height and the monitor cannot swivel or pivot. To be fair, it looks relatively sleek, thanks to its ultra-thin bezel on all four sides.

The screen itself is vibrant with accurate colours, which is unsurprising because it boasts an in-plane switching (IPS) panel. Viewing angles are excellent.

At $639, the BenQ is slightly cheaper than a similar 27-inch IPS monitor like the Dell U2715H ($769). On the other hand, the Dell monitor does offer height adjustment, tilt, pivot and swivel functionality, as well as USB 3.0 ports that are missing on the BenQ.

• Verdict: With its ambient light sensor, the BenQ EW2770QZ Eye-Care monitor is suitable for those in an environment where the lighting conditions change throughout the day.