What Is a Privacy Filter?

By Natasha Gilani

Privacy filters protect computer screens from shoulder surfers.
i monitor image by eka from Fotolia.com

A privacy filter, also called a privacy screen or a monitor filter, is designed to protect a laptop or the screen of a desktop monitor from prying eyes and shoulder surfers. They decrease the viewing angle, allowing only the person sitting immediately in front of the screen, typically the user, to view the contents of the screen. Privacy filters fit directly above a monitor screen and attach securely in front. Privacy filters also reduce radiation and glare generated from LCD and CRT computer monitor displays.

History and Manufacturing Information

Privacy filters were first introduced in the 1990s by 3M, formerly called Minnesota Mining and Manufacturing Company, based in Two Harbors, Minnesota. Privacy filter technology was improved in the 2000s and currently the company manufactures a wide range of privacy filter products. 3M privacy filters come with a limited warranty of 1 year from the time of purchase.


3M privacy filters feature micro-louvre technology that prevents prying eyes from viewing the contents of a screen. Privacy filters are made of thin sheets of plastic film, not greater than 2 millimeters in thickness. They block the screen from all unintended viewers, allowing them to see only a black rectangle in its place. Privacy filters are flat, thin panels that come in two basic designs: framed and frame-less. They are designed to fit and detach quickly, fitting neatly into the bezel for both wide-screen and regular CRT and LCD displays.

Types and Sizes

There are many types of privacy filters available in the market, with the three most common being laptop privacy filters, LCD monitor privacy filters and CRT monitor privacy screens. They come in various sizes, depending on the size of the display screen, such as 12, 13, 14, 17 and 19 inch screens. As of August 2010, privacy screens for mobile phones are also available, including those for Blackberry, Nokia and iPhone handsets.


Privacy filters are an ideal solution for users who work in high-traffic industries and areas. They are used to protect sensitive data and information for insurance, banking, finance, human resources, trade, examination rooms and medical personnel. Privacy filters are also used by government officials conducting sensitive operations and homeowners who are sticklers for privacy.


Privacy filters allow computer users to maintain confidential and private information. It enables them to work in crowded areas, trains, airports, coffee shops, buses and offices without having to worry about passersby gazing at their screens. Privacy filters protect sensitive intellectual property, reduce glare and prevent computer-use related headaches. They also protect computer and cell phone screens from abrasions, scratches and dust.