Why do you see the scenery outside moving slowly through the glass on the EMU? Is there really a so-called "speed-reducing glass"? But it doesn’t hold true according to optical principles!

Nowadays, many media mistakenly believe that transmission vehicles are equipped with "deceleration glass", thinking that it can slow down the speed of the scenery outside. In fact, this is a mistake that goes against science. "Deceleration glass" is a wrong concept. There is no such thing as "deceleration glass" in the world. In fact, whether it is the window glass of the EMU or the front windshield of the car, it should be called "vehicle safety glass". It is actually a kind of laminated glass, which is made of two layers of tempered glass with a layer of PVB film sandwiched between them. When the glass is damaged by external force, the glass fragments will still stick to the film and will not fly out and cause secondary damage to the vehicle occupants. The high-quality front windshield has good optical properties, good light transmittance, and no light distortion. It can very truly reflect the shape and movement of the scenery outside, and the vision is very clear, just like the visual effect without glass. In addition, Sandwich technology also has a certain effect of heat insulation and soft light, making people feel more comfortable.

Then why is it unpleasant to see the scenery outside in the EMU? The main reason is that the EMU's roadbed is elevated, which is usually far away from the scenery, and the windows are wide and the field of vision is wide. The variable that people use to judge motion perception is not linear velocity, but angular velocity (viewing degrees/second). A point-like object moves at the same speed. If its direction of movement is exactly parallel to the line of sight of the eye, the angle of view at this time is 0° (of course, since a person has two eyes, it is impossible for both eyes to be 0. In fact, it can only be Close to 0), that is, the angular velocity is 0, and you can hardly feel it moving; when the direction of movement is perpendicular to the line of sight of the eye, the angular velocity is maximum, and you can feel a very fast movement speed. In addition, for the same linear speed, the farther the distance, the smaller the angular speed, and the slower the speed feels. For example: The earth we live on is a high-speed moving celestial body, with an average linear revolution speed of about 30Km/S! What other car can compare? But can we feel it? No, why? Could it be that our earth is also equipped with "speed-reducing glass"? No! It is because the reference object we can see (such as the sun) is too far away, and the angular velocity is very small, less than 1° per day on average. People can hardly distinguish such a slow angular velocity, which creates the illusion of "slowness"! Next time you take an EMU, get close to the glass window and look down at the roadbed and poles next to the EMU to see if it's still very slow?

What kind of "deceleration glass" should be installed on the EMU when the speed is more than 200 kilometers per hour? It is not said that the aircraft is "deceleration glass" when the speed is more than 800 kilometers per hour. What should I do if the fighter jet is thousands of kilometers high? What about a space shuttle that's faster than a fighter jet? Therefore, the so-called "speed reduction glass" is a pseudoscience invented by scientifically illiterate people. Please stop continuing this ignorant joke.