What Are The Performance Indicators Of Touchscreen ?

Performance indicators of touchscreen include environmental guarantees, mechanical, optical characteristics, electrical characteristics, durability, and environmental reliability. There are certain performance indicators for each performance. According to the different integrated touch screen products, the performance indicators are also different. In addition, the performance indicators of the product are also different depending on the touch screen method. The example cited is the performance index of a capacitive touchscreens product on products such as integrated machines, medical or industrial computers.

What Are The Performance Indicators Of Capacitive touchscreens ?

Environmental Guarantee For Performance Indicators Of  Capacitive touchscreens

The environmental characteristics include indicators such as drive temperature range and storage temperature range. -20 ~ 70 degrees is the driving temperature range, and -30 ~ 80 degrees is the storage temperature range. If it is a standard reliability specification, the driving temperature is 50 degrees. And the storage temperature is -20 to 65. If it is a vehicle-mounted product, the reliability specification is stricter. The driving temperature range is -30 to 85, and the storage temperature range is -40 to 95 degrees. In-vehicle products with touch screens occupy a large market. As mentioned above, the mainstream structure and manufacturing process are also different depending on whether it is an embedded type, a universal type, a matching type, etc.

Mechanical And Optical Properties

1.Action Load

Mechanical and optical characteristics mainly measure the action load and transmittance. The action load is a unique function of the touch screen and refers to the degree of stress. Using silica gel (for example, the front end has a hardness of 60HS), the on-resistance is below 10kft. According to different recording methods, such as finger recording and dictation, the required values are also different. Written entry products have relatively low requirements on the action load.

2.Transmittance

The touch screen is usually set on the top of the liquid crystal display (the side that people can see), and the transmittance is a very important performance index. As a display device, brightness and contrast are the combined effects of the characteristics of the liquid crystal display panel and the touch screen. By setting the touch screen,it can increase the brightness of the LCD panel's backlight to compensate for the decreased brightness of the touch screen. So that it can compromise the relationship between brightness and power consumption. The measurement method is to use a halogen lamp as a light source, use a polarizer to convert it into a linearly polarized light source.

Moreover, use a brightness of 550me as 100% to measure the transmittance. In addition, the optical characteristics indicators include reflectance, surface haze. There will also include surface hardness and other performance indicators in the range of performance indicators. We can use it on the upper substrate of the touch screen. And it may be determined by the surface treatment performance of the laminated film.

Electrical Characteristics

The electrical characteristics of the touch screen mainly include resistance between terminals, insulation resistance, chattering, linearity and so on. One of the most important performance indicators is linearity. When the we touch the touch screen , it is necessary to make the actual detected position and the touched position consistent. But there will be some deviations in fact. The ideal relationship between input voltage and output voltage is linear. But the actual output voltage often fluctuates. Introducing the concept of voltage linearity. That is, the value of the outermost voltage difference in the effective area divided by the maximum error voltage in a panel is called linearity.