Angle of Mobile Phone Privacy Film and VLT Test

From:Linshang Time:2021/03/05 09:38:23 Browse:38

Privacy film, as the name implies, is a film to prevent peeping. Users can only read the information from a positive perspective and what they see from the side will be a dark screen, which can effectively protect business secrets and personal privacy. Privacy films are commonly used on ATMs, mobile phones and laptops. From the material point of view, it can be divided into a PET privacy film and a privacy protection film made of toughened glass. The privacy film has different angles. Users can choose the right angle according to their needs. So what kind of privacy film can be called a high performance privacy film? The most important thing is of course that the anti-peep effect is good. Another thing is that the visible light transmittance should meet the requirements. After all, it is mostly used on mobile phones and computers. The privacy film needs to have a certain light transmittance before it can be used correctly. Next, we will introduce the angles of the mobile phone privacy film and how to measure the visible light transmittance of the mobile phone privacy film. If you want to know the answers to these two questions, just keep up with us.

1. What are the angles of mobile phone privacy film?

Choose a line from the screen as the middle baseline, the visual direction (line) and the vertical line form an angle, about 30 degrees on the left and right sides are the viewing angle. 60 degrees is the invisible angle, that is, the privacy angle. The smaller the viewing angle, the greater the anti-peeping angle and the better the anti-peeping effect. Conversely, the larger the viewing angle, the smaller the anti-peep angle and the worse the anti-peep effect. There are many angles of mobile phone privacy films. The common privacy films on the market are 28 degrees, 30 degrees, 33 degrees, 45 degrees and so on. Generally, privacy filters with a degree of 30-45 degrees are recommended to purchase. The anti-peep film with different angles has different anti-peep effects. When purchasing privacy film, you can choose the right angle according to your needs.

viewing angle of privacy film
viewing angle of privacy film

2. How to measure visible light transmittance of mobile phone privacy film?

The visible light transmittance of the privacy film is an important indicator to measure the quality of the privacy film, because the light transmittance determines whether the screen is clear when we use electronic equipment. Generally, the visible light transmittance of privacy films on the market is around 50%-70%. Today we will use LS117 light transmittance meter (diffuse transmission principle) to test the privacy film of 28 degrees and 33 degrees, and see how the light transmittance of the privacy film is at these two angles.

optical density meter test 28° privacy film

optical density meter test 28° privacy film

densitometer test 33° privacy film

densitometer test 33° privacy film

As can be seen from the above figure, the visible light transmittance of the privacy film at these two angles is not the same. The light transmittance measured by the light transmittance tester for the 28-degree privacy film is 54%. The light transmittance measured by the light transmittance tester for the 33-degree privacy film is 59%. Knowing the light transmittance of these two privacy films, it is easier for us to choose. Users can comprehensively evaluate the two data of privacy angle and visible light transmittance and choose a privacy film that suits them.

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