Using computers outdoors with polarized glasses

I’ve recently had the unexpected experience of finding myself comfortably coding outdoors in almost direct sunlight, wondering how in the world I could see the screen so clearly in conditions that would have ordinarily made for a headache-inducing and vision-destroying squinting session.

Turns out I had inadvertently kept on my new, polarized sunglasses on and they were making a world of difference.

The screen of my 13-inch, M1, 2020 MacBook Pro (model A2338) must produce light of the same polarization that is let through by the polarizer in the sunglasses, the unassuming PLD 7031/S from Polaroid. As natural light spreads across all polarizations, the glasses block far more of it than they do of the screen’s.

Effectively, the sunglasses dim the world around the screen more than they dim the screen itself, partially compensating for the difference in brightness and making for significantly more pleasant working conditions.

After concocting a ridicoulously over-engineered Lego™ stand that allowed me to use the glasses as filters for my phone’s camera, I was able to clearly verify and capture the effect:

From left to right: a screenshot of what was being displayed, a photo of the screen without sunglasses, a photo of the screen with sunglasses.

Unfortunately these pictures do not make justice to the magnitude of the difference made by the polarized lenses, likely due to the camera’s inferior dynamic range (compared to that of the human eye) and to the phone’s internal image processing.

Never miss a chance to play with Lego™, particularly as a grown-up.

Staring at computer screens outdoor in bright light for long stretches of time may still damage your vision, polarized lenses or not. Do so at your own risk! Furthermore, do not make the mistake of getting sunglasses with poor or absent UV protection as they will cause more damage your vision than having no glasses at all would. Aim for eyewear with UV400 protection or similar.

With that disclaimer out of the way, the combination of the MacBook’s bright screen and of my polarized sunglasses, together with an adequate amount of shade, truly made for a couple of hours of very pleasant work with none of the discomfort I had experienced in previous outdoor working sessions.