Dell Inspiron 17 (5749)’s screen isn’t doing well in our tests – it has PWM across all brightness levels

LaptopMedia.com News Dell Inspiron 17 (5749)'s screen isn't doing well in our tests - it has PWM across all brightness levels

From: Rossen Pandev 16 April 2015 / 15:04 2

That’s one heavyweight workstation with 17-inch touchscreen that might not be ideal for travelers, but it will surely fit in your office as a replacement of a big, power-hungry desktop machine. However, its display properties might not be as good for long hours of work either. The results from our tests are in and they don’t seem promising.

Dell Inspiron 17 (5749) uses a TN panel with glass protection and touchscreen capabilities. The backlight of the display emits PWM (pulse-width modulation) or simply put – screen flickering. That’s considered to be damaging for the human vision and after long hours of work you might feel tired, have sore eyes or even a headache. Unfortunately, the brightness level doesn’t affect the frequency of the emitted light much. For instance, when you set the display at 100% brightness, the display stays without the backlight on for about 5-10 µs with a frequency of 1kHz. So in this scenario, the display isn’t all that tiring, but still emits PWM. At lower levels of brightness, the situation grows worse as the screen flickering becomes more aggressive, thus more harmful to your eyes. If we can rate it from 1 to 5, we can give this display 2/5 rating in terms of user friendliness. You can see the chart below.