Three, electromagnetic classification
01Electromagnetic pen
According to the electromagnetic pen, it can be divided into active pen and passive pen.
(1) Active pen-active electromagnetic pen
The active pen emits electromagnetic signals through the built-in battery, and it can continuously emit electromagnetic signals regardless of whether the electromagnetic pen is near the electromagnetic screen or not. The electromagnetic signal is strong, the response speed is faster, the size can be larger, the power consumption is low, and the anti-interference ability is stronger. , But the cost of the electromagnetic pen is high, and it needs to install a battery or charge. Only active pens can be used for large sizes. The size of the pen is limited by the size and weight of the battery.
(2) Passive pen-passive electromagnetic pen
Passive electromagnetic has high power consumption relative to active, and it can only be made in a small size, up to 22 inches, with weak corner signals and only single pen touch. The advantage is that the electromagnetic pen does not require power, and the stylus of portable equipment can be used. Is very small. Passive pens require higher antenna boards than active pens, and the solution of active pens is more expensive than passive pens in the same small size. The passive electromagnetic pen is not close to the electromagnetic screen and cannot receive electromagnetic energy. The longer the distance, the weaker the signal, but because it does not require batteries, it is light and has no requirements for the pen. It has more advantages for pens under 20 inches. At present, there are more small sizes on the market. Such as e-commerce signature boards, pos machines, e-readers, etc.
02Material
According to the material, it can be divided into transparent and opaque. The former can be applied to direct-lit backlights and edge-lit backlights; the latter can only be applied to edge-lit light sources.
(1) Side-type backlight
The edge-lit LED backlight is to arrange the LED dies on the periphery of the LCD screen, and then match the light guide plate, so that when the LED backlight module emits light, the light emitted from the edge of the screen is transmitted to the central area of the screen through the light guide plate. , In this way, the overall amount of backlight is available, allowing the LCD screen to display images.
Advantages: less LED crystal material can be used, saving the cost of LED crystal material; light and thin body
Disadvantages: uneven brightness, need to add DBEF; large size has certain safety hazards; poor stability, high overall cost; troublesome assembly.
(2) Direct backlight
The following formula is to arrange the LED dies evenly behind the LCD panel as the light source, so that the backlight can be evenly transmitted to the entire screen, and the screen details are more delicate and realistic.
advantage:
1. The picture receives light and heat uniformly, and the color picture is more delicate;
2. Strong stability and no safety hazards;
3. Low overall cost;
4. Simple and quick assembly;
Disadvantages: Thick body.
In summary, the direct type is the best choice for medium and large interactive tablets! Transparent electromagnetic antenna board is the best choice for direct interactive flat panel!
Fourth, the advantages and disadvantages of transparent and non-transparent electromagnetic
1. The new product, transparent electromagnetic, can achieve an excellent electromagnetic writing experience on the one hand, and on the other hand, the light transmittance exceeds 90 percent , which has no effect on the brightness, so it can be used in direct-lit backlight structure or edge-lit backlight. structure;
2. Compared with the traditional silver-brushing method, the printed transparent electromagnetic antenna board has stable quality and is not easy to break; at the same time, the key parts adopt the laser welding process, which is firm and reliable, and has high stability;
3. The printed transparent electromagnetic antenna board has lower mold opening cost, better compatibility, and lower overall cost.
