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Laptop Privacy Filters: What to Look For and Why You Need One

Brett Nuckles
Brett Nuckles
Director and The 'Voupons Monster' Keeper at Voupons

Strong passwords and solid encryption technologies go a long way toward keeping your private work data private. But those tools can’t stop someone from simply peering at your screen from over your shoulder, or worse – snapping a photo of what you’re working on. It’s called visual hacking and it’s a serious security threat that businesses shouldn’t ignore.

Thankfully, there’s an easy fix. Simple privacy filters that adhere to a laptop’s display can severely restrict the viewing angle, so that only someone sitting directly in front of the screen can see what’s on it. Anyone trying to sneak a peek from the sides or top will just see a blank, black screen.

How does it work?

Privacy filters are surprisingly low-tech, consisting of a polarized plastic sheet. Polarization works as an optical filter that blocks out light from certain angles – in this case, all angles but the one right in front of the screen. It’s the same technology used for polarized sunglasses and some types of camera lenses.

Why you need one

The need for a privacy filter will vary depending on the employee’s work habits. Of course, those most at risk of visual hacking use a computer in a public place, or in close proximity to clients or customers. Due to the nature of their work, frequent travelers, as well as employees in customer service or sales positions, could be particularly susceptible to visual hacking.

It takes just a few seconds for someone to glean confidential information from a computer screen, which could potentially be used for malicious or illegal intent. The risk is especially high given the ubiquity of smartphones with high-quality cameras, making it extremely easy to snap a quick photo without anyone noticing.

In fact, 3M used white hat hackers in a study to investigate the phenomenon. Hackers tried to glean confidential information using visual hacking from more than 100 companies in 16 industries. They were successful in nearly 90 percent of trials, and it usually took 15 minutes or less. Hackers were able to recover nearly five pieces of sensitive information in each trial, including financials and confidential employee and customer information – using nothing but their eyes.

Ultimately, assessing your company’s true risk of visual hacking is going to be difficult. For some businesses, simply educating your employees about the issue can be enough. After all, many employees are not actually aware of what types of information are sensitive and should be protected. For other companies, privacy filters for laptop screens – which are relatively cheap and easy to install – are a no-brainer.

What to look for

  • Image clarity: Privacy filters tend to block some light from laptop screens, making them appear dimmer. Different models differ in this regard, with the best-rated filters being made by 3M. The company now makes a High Clarity Privacy Filter model, which claims it can offer up to 30 percent better experience than a regular black filter. Dimming can be offset by turning up a screen’s brightness, but that in turn can diminish your battery life.
  • Application: The way that you’ll apply the filter to your laptop screen varies from model to model. Filters made by 3M are easy to apply and remove over and over because they adhere using reusable micro-suction strips that don’t leave any sticky residue.
  • Size: Privacy filters come in all the standard laptop sizes.
  • Matte finish: Some privacy filters can give glossy laptop screens a matte look, which helps ward off distracting reflections but can make colors look dull. Some filters are reversible, letting you choose a matte or glossy side before applying.
  • Color: Privacy filters come in a couple of different colors. The basic filters will look black when viewed from an angle. You can also buy filters that give off a gold sheen when viewed from the side. Gold filters are more expensive because they won’t dim your screen as much, but they also tend to be more reflective than black filters, so they’re bad for people who work outdoors. The vibrant gold sheen can also be distracting to workers sitting nearby, even if they aren’t trying to spy on you.
  • Price: Privacy filters typically cost between $30 and $50 each.

What’s next: Built-in privacy filters

You may not have to worry about buying or installing privacy filters, because some laptops come with the feature built into the display. HP's laptops with Sure View technology comes with a privacy filter that can be toggled on or off with the push of a button.

Sure View – which was developed with 3M's help – was first be available on the EliteBook 1040 and EliteBook 840 laptops in 2016. Pressing the F2 button on those systems transitions the screen into privacy mode using a special backlight and filter overlaid onto the display. In practice, it works just like the existing black privacy filters, with one key advantage: the filter can be toggled off when it’s not needed.

That’s a big perk for workers who don’t want to deal with the privacy filter’s dimming effect when working in the office. It also makes it easier to share information on your screen with someone sitting next to you, since the privacy filter can be toggled on or off instantly.

Sure View will bump up the cost of your laptop by about $75, which makes it costlier than the average screen filter. But keep in mind that it’s a one-time cost, and will never have to be replaced due to typical wear and tear.

So far, HP is the only company to debut laptops with built-in privacy filters. We’ll have to wait to see if other laptop makers adopt similar technology.

Brett Nuckles
Brett Nuckles
Business News Daily Contributing Writer
A former Ohio newspaper man, Brett Nuckles fled the Midwest in 2013. He now lives in Seattle, where he spends his days tinkering with smartphones, tablets and computers. He loves to think about the intersection of technology and productivity, and how to get the most out of new gadgets and apps. He's also a big fan of vegetarian food and digital painting. In his off hours he spends most of his time drawing and painting sci-fi/fantasy scenes on his PC with his trusty Wacom stylus in hand.