Waterproof has become a magic weapon for many flagship mobile phones. What is waterproof? How mobile phone manufacturers do it. Recently, technology author Sean Hollister has sorted out the waterproof technologies of Samsung, Apple and Sony. Although the waterproof technology is already very advanced, please note that waterproofing is not equal to water resistance. In the strict sense, there is no real waterproof mobile phone in the world.
If your phone falls into the pool or is in the toilet, in general, you are unlucky and the phone will be damaged. Unless you are very lucky, the board can continue to be used after drying. If you are using a waterproof phone, such as the new iPhone 7, Galaxy S7 or Sony Xperia XZ, the situation will be completely different.
I am a Samsung Galaxy S7 user, I can tell you clearly: the waterproof performance of the phone is shocking. I didn't take my mobile phone to swim, or do similar things. In the following environments, I can use S7 without any pressure:
——The sky is pouring rain. I am writing an email. I have not finished writing it. It is not necessary to terminate because of the rain.
- If you are inspired by the shower and want to write something, you don't need to dry the phone before you finish writing.
- If there is stain on the glass screen, I can wash it directly with water.
- Sometimes, I put my phone in the hot tub and shocked my friends.
not bad. What makes the phone waterproof? Or how is the phone waterproof? You may be learning about the pros and cons of the new iPhone, or just wondering if the phone will be damaged in the pool. Let's answer your question.
How is waterproofing achieved?
iFixit dismantling engineer Scott Havard asked us to draw an egg: the eggshell is perfect and there are no cracks. Obviously, water cannot enter the egg. Now that we have replaced the eggs with Easter colored eggs, it is a bit difficult to keep the water out of the egg.
Harvard said: "If you have an Easter colored egg, it can be divided into two halves. Suddenly, it becomes very difficult to waterproof." The water will have no resistance to penetrate the gap and eventually pass through the gap. Harvard said: "If the pressure is so high, the water molecules will enter the equipment."
There are gaps in mobile phones, not just one, but many. There are interfaces, buttons, speakers, speaker grids, and microphone connectors, which leave tiny gaps that allow water to enter the phone. Not only that, there is also a gap between the screen and the phone frame.
Harvard says modern glass screens are fragile and pose a big challenge to waterproofing because manufacturers can't permanently attach glass screens to frames.
How to do? Manufacturers have adopted a simple technique: bonding with an adhesive.
Sometimes, we call the adhesive a gasket, seal, tape or glue. The name may be different, but the meaning is the same: the manufacturer's highly viscous rubber glue creates an air-tight space.
Disassemble any waterproof phone and we will find that there is a thick sticky material inside, which will stick the screen to the base. Manufacturers apply glue to the back of the interface (ie USB, Lighting, 3.5 mm headphone jack), and sometimes the circuit near the frame is glued.
Adhesives are not omnipotent and sometimes do not work. Some components on the phone are prominent, such as buttons, connectors, and removable components. We certainly don't want slimy glue to flow out.
The manufacturer then introduced a rubber gasket, which is an O-ring, placed inside the device and attached tightly to the inner surface.
We can find the rubber gasket near the earphone interface and charging interface of the mobile phone, and there is also a small rubber gasket near the SIM card holder. Apple also installed washers near some cable connectors for added protection.
As for the buttons, the manufacturers use different techniques, they use a small amount of silicone rubber to separate the physical components squeezed by the user from the internal electrical contacts. For the sake of understanding, we can make an analogy: it is raining outside, we walk into the watery sidewalk, in order to prevent water from entering the shoes, we can put a plastic bag on the feet. In the phone, we will eject the SIM card tray through the small button of the “paper clip”.
No water leakage, but air can enter
There are a few components in the phone that are not completely sealed.
The speaker and microphone need to let the air circulate, because only the air vibration will sound. If the phone does not allow air to enter at all, the pressure inside the phone is not balanced with the outside, and the pressure will open the gap on the sealed phone to allow water to enter.
In this case, how can manufacturers block the entry of water? science. Many manufacturers use a very fine mesh in front of the speaker and microphone when making a waterproof phone. It completely follows the natural characteristics of water, such as cohesion and surface tension, allowing water to stick together rather than through the mesh.
There are also places where the same technology is used, such as the speaker grid on the left side of the iPhone 7 or the microphone of the Galaxy S7.
In addition to the mesh, the manufacturer has added a waterproof fabric breathable membrane (ePTFE) that allows air to pass freely and balance the pressure. Gore produces the ePTFE material Gore-Tex, which is the same material used in ski jackets. According to Core, they have sold up to 1 billion portable electronic vent components.
Some manufacturers (such as Samsung) sometimes close the interface briefly to prevent shorting of the charging interface. They use corrosion-resistant materials (such as nickel) to prevent the phone from wearing out.
For this reason, modern waterproof phones are waterproof without the need for a waterproof cover.
Waterproof is not
All waterproof technology is not perfect. The so-called waterproof mobile phone is not "waterproof" in a strict sense.
Harvard said: "If the pressure is large enough, the water will pass through, but the pressure required is different."
It is for this reason that during the promotion, Apple, Samsung, and Sony only said that the mobile phone can be "waterproof" and did not say that it can "resist to water."
If you add some chemicals to the water, the situation will be different, such as adding some salt.
Sony once advertised that Xperia phones can take pictures underwater. In 2015, Sony encountered trouble in Australia, and local regulators and citizens claimed that the phone was found to have failed after swimming. One thing that Sony might not have considered is that Australia's home pools are typically filled with salt water, which can corrode and invade waterproof phone seals.
Soon, Sony changed its tone, and it clearly told users not to use the phone underwater, away from salt water.
Since then, Sony's attitude has softened somewhat. The company claims: "If you want to take the equipment underwater, watch the diving movement at a close distance, or record the child's first swimming class, go, no problem." But Sony Remind that this recommendation only applies to swimming pools with chlorinated fresh water (not salt water). IPX8 (protection level) mobile phones can handle it, but only afterwards, clean the chlorine with fresh water.
Apple also warned users that although the new iPhone is waterproof, there are still some things that can't be done.
When companies tell us that mobile phones can be waterproof, what they mean is that in a certain amount of water, the phone can last for a while.
How long can it last? The specific depends on the IP rating.
We don't talk too much about the IP rating system. When testing, it depends on how long the phone can "live" in the following environment:
- Can survive in fresh water droplets.
- Can survive in the freshwater rapids.
- Can you persist for a period of time, such as 30 minutes, in a few feet of water?
Although the product has reached a certain IP rating, it can only prove that the manufacturer can pass the test in the laboratory. If you actually bring your phone to the water and drop it into water or other liquids, the results may be different.
Even if there is an IP rating as a guarantee, the phone may be damaged if there is slight wear and tear. In addition, if you just remove the phone, you can't guarantee it will be available right away. Apple recommends that users dry first and wait at least 5 hours before charging.
Incoming water can not be guaranteed
Although companies claim that their phones are waterproof, there is no one company that guarantees water in the water. Apple, Sony, and Samsung all made it clear that mobile phones damaged by water are not covered by the warranty. Inside the phone, every company has a sticker that can be damaged if it is contaminated with water.
Is it possible that the circuit is wetted by water? possible. Samsung has launched the Galaxy S7 Active phone, which has problems with waterproofing. Samsung agrees that it can be replaced because it has been damaged by water in less than one year.
The representative of Samsung told us that if the customer asks, they will investigate the mobile phone damaged by water; the Sony representative said that as long as the usage environment does not exceed the limit specified in the promotion IP rating, if the mobile phone is in the first year of purchase, Damaged, Sony can be replaced.
These promises are not written in black and white, so don't be too convinced, they may tell you directly: Comrade, the phone is in the water, it is damaged, it is your own. Remember, Apple didn't give any promise.
Say one more: I probably shouldn't play the Galaxy S7 in the hot tub!