Does Dark Mode really save battery life on OLED screens?

In the last few years there has been a real crazy with the ‘Dark Theme’, or as it says, dark mode, in all that is smartphones equipped with OLED screens.

What deep down, makes perfect sense! After all, the color black on this type of screen is equivalent to pixels off … And if they are off, they are not spending the battery! It is not?

With the spread of ‘Dark’ themes, an issue began to appear in the minds of users and designers. Should the dark theme be ‘AMOLED Black’ or just a Dark Gray?

On the aesthetic level, this is purely from the taste of each one. But at the level of battery saving, the results are extremely interesting! If you do not know, the dark gray continues to mean a battery saving, and apparently, it is not so different from the savings of the black color.

So … What’s the difference between a Dark Mode completely black, and Dark Gray Mode? First, we have to realize how an OLED screen works.

(Super simple explanation)

In an OLED (Organic Light-Emitting Diode) screen, each pixel is responsible for its own light. That is, each pixel has a red, blue and green (RGB) sub-pixel, these are the individual OLEDs that emit their respective color depending on the brightness setting. Of course, this brightness depends on the applied voltage.

Therefore, all the colors that the screen produces, is a mixture of these three OLEDs, with different brightnesses. And as we said above, the black color is the absence of color of these three colors, which in turn means that 0 volts are used.

So how is the dark gray mode?

Curiously, Gray, Dark Gray, and Light Gray are all colors that come from the color white. That is, a gray pixel is formed from a white pixel that sees its voltage reduced.

Of course, we still have the gamma, but we will not go in here, for the simplicity of the thing.

So how much energy consumes a dark gray pixel?

Let’s use the recommended specification for the Google Material Dark theme, code # 121212, which means rgb (7%, 7%, 7%). Well, after the gamma correction (0.07 ^ 2.2) we have a value of 0.3%, which means that Google’s dark gray theme generates 0.3% of the brightness of a pure white surface.

As we said above, the brightness of an OLED depends on how much voltage is being applied. Therefore, only 0.3% of the white color is needed to render the color Dark Gray.

0.3% continuous to be more than 0%!

Obviously yes, but here we are talking about an increase in whimsy consumption, which will have a very small impact on the battery of our everyday device.

If you need help, have doubts or concerns, do not hesitate to leave a comment in the comment box below and we will try to help you as soon as possible!

ANKIT BHARDWAJ: Ankit Bhardwaj is Founder of 'TechKhiladi'. Engineer by Profession and an enthusiast entrepreneur and blogger. He has a very deep interest in learning things related to the digital world and love to sharing his knowledge with others through blogs.