Why not make a smart TV a touchscreen?

PeterWint

Member
The touch screen of the mobile phone is easy to do. If we think in terms of magnification, we also think that it is reasonable to make a TV. In fact, it is not true, because mobile phones, pads, and even laptop screens are small and medium-sized products. Within the scope of small and medium sizes, the implementation of touch screen is relatively simple-only need to add a touch screen module inside or outside the display screen. . But have you ever thought about a question, what wire is used to make the signal detection circuit of the touchscreen?

Why not make a smart TV a touch screen?

The wire for making the touch screen detection signal is called touch sensor for the time being. Tx is used for the transmitter electrode and Rx is used for the receiver electrode. A touch chip is used to monitor the capacitance change between Rx and Tx in real time. When our fingers touch At a certain point, the chip reviews the position of the finger and gives interactive instructions. It can be seen that the Rx and Tx of the touchscreen are made of transparent conductive materials.

The following is a brief introduction to transparent conductive materials. The most commonly used transparent conductive material is ITO, but the problem with ITO is that the square resistance is large. Therefore, in order not to cause too much pressure to the touch chip, the trace size requirements of ITO are very high. Therefore, in the small and medium size products, due to the small size of the display, the trace length of the touch is not too large, so that the overall trace resistance of the touch is within a reasonable range, and the chip can support its work. . If you zoom in to a 40-foot TV, then the problem is coming, the wiring is too long, and the resistance is too big! The chip can't be brought up! So now we have not seen TV products applied to touch screen TVs with ITO as touch traces.

But can't a large touch like a TV be realized? The answer is no, because we can abandon the ITO material and use other conductive materials instead of ITO for touch traces. Then the question comes again, what material is the conductive material to replace ITO, and the square resistance is small? Metal materials! Then the question arises again, why the metal material has a small resistance, and the small-size display does not use it as a touch electrode? Because of its low transmission rate! Although ITO has a large square resistance, but its high transmittance, it is widely used in small-size touchscreens.

Metal materials are opaque, but in an ultra-thin state, or in a nano-scale state, the light transmittance will rise to more than 80%, so in large-size touch, metal wire, such as nano silver , Nano-zinc, nano-metal grid and other methods are well-received. So why are there no large-size touch products made of metal materials?

Metal materials are easily oxidized, so the manufacturing process is more difficult, and how to block water and oxygen is also a relatively rare problem, which needs to be solved by R&D workers. What is the large-scale touch solution that has been mass-produced at this stage? Infrared touch control solution. Non-capacitive touch. Because infrared touch detection accuracy is good, and it also supports multi-touch, it is a relatively mature large-scale touch solution, but infrared touch requires a circle of infrared sensors on the periphery of the TV, so the TV will be very ugly.
 
I don't want a touchscree TV at home. Sit on sofa, no way to get up and change channels by touching. I want a smart AI.
Besides there is touchscreen TV already which is used for classroom/ meeting/office. You can all it a large touchscreen monitor.
 
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