Views: 214 Author: Reshine Display Publish Time: 2023-11-01 Origin: Site
TFT LCD display with touchscreen capabilities enables more efficient operations. It is being used in an increasing number of applications. There are five types of touchscreen technologies, each with advantages and disadvantages in terms of cost, picture quality, touch sensitivity, and durability.
Important performance specifications to consider when selecting a TFT touchscreen for your project.
TFT touchscreens, as previously discussed, have distinct advantages and disadvantages. By weighing the pros and cons, choice becomes a compromise. Capacitive touch projection is ideal for harsh, industrial, and outdoor applications. Such applications will not benefit from IR technology. However, if clarity is important, an IR touchscreen is a good choice.
This is the ability to provide consistent touch performance in devices when the TFT touchscreen is exposed to electric or magnetic noise. The user must be able to select the target on the screen correctly without accidentally touching adjacent objects.
The number of active touch-points and simultaneous touch-points supported by a TFT touchscreen is referred to here. This has an impact on pointing precision and selection errors. A higher-resolution screen offers more touchpoints and better pointing.
The faster a TFT touchscreen responds to touch, the more satisfied the user will be with the touchscreen. According to research, humans require less than 10ms to feel at ease with a touch response. The SAW touchscreen has the fastest response time, which is approximately 10ms. IR, on the other hand, has a faster response time of around 20ms.
Touchscreens are typically mounted on top of TFT LCDs. As a result, there is a loss of light, which affects image clarity. Because an IR touchscreen has no overlay, its transmission is 95% 100%, and its clarity is the best among all touchscreen solutions. In this category, the resistive type has the lowest rating.
The deployment environment of the product also influences the choice of a TFT touchscreen. If the TFT touchscreen will be used in an outdoor and harsh environment, the type chosen should be one that can withstand dust, temperature, moisture, and so on.
The performance of the TFT touchscreen is expected to degrade when it is actively used. The IR touchscreen has a lifespan of about five years, while the capacitive type has a lifespan of about two years.
There are numerous factors to consider when selecting a touchscreen, most notably the application and environment in which it will be used. Please contact us if you require more information on selecting the best touchscreen technology for your project.
The term "Burn-in" refers to the retention of TFT LCD images. This caused the phosphorus in CRT displays to wear and the patterns to be burnt into the display. On LCD screens, however, the term "burn-in" can be misleading. No actual burning or heating is going on. What should you do if you have a TFT LCD burn-in problem?
A noticeable discoloration or ghosting of a previous image on a display is referred to as burn-in. It is caused by the constant drive of some pixels more than others. Do you understand how burn-in occurs?
The liquid crystal (LC) within the TFT is an ionic substance that twists in response to the external electrical field.
An AC signal should be used to drive the LC inside the TFT. A DC signal would destroy the LC ionic structure; there is no perfect symmetric AC signal;
When the TFT LCD pixels are continuously driven, the slightly unbalanced AC attracts free ions to the internal surface of the pixel. With the AC driving voltage, those ions act as an additional DC.
Fixed Method for Repairing and Preventing TFT LCD Burn-In
In short, the fixed image displayed on the screen will not cause a burn; if a burn occurs, we can try the following to reverse it:
Turning off the TFT for a few hours (ideally 48 hours) may resolve the issue; creating an all-white image and moving it on the screen with the backlight turned off for a few hours.
These burn-in fixers and screen repair software may be useful. When Image Retention occurs on a TFT, it can easily reappear. As a result, we must take preventive measures to avoid the recurrence of burn-in.
Screen saver: When the system is idle, allow the pixels to display something different. Displaying static images for more than 20 minutes is not recommended.
Clear screen: fill the screen with white or black to ensure that every pixel is driven evenly when the system is idle.
When the system is idle, turn off the TFT LCD backlight to extend the life of the LEDs.
When applicable, turn off the entire TFT to eliminate any pixel drive.
Keep the display signal with TFT power to avoid static DC drive to the pixels.
The power on/off sequence is something we must be aware of.
TFT LCD Burn-In Test (Example) Standard Test Conditions:
Room temperature; Black and white chessboard display pattern (approximately 60x60 pixels per block); Displaying for 30 minutes.
Wait for 10 seconds and no burn-in appears on the screen.
(Be aware that this is a destructive reliability test! - Please contact us for more information on sampling rates and individual product standards.)
The white area of a normal white TFT LCDs minimal drive, while the black area displays maximum drive. Free ions within the TFT may be drawn to the black area (maximum drive area).
When the display content was changed to a full screen of 128 (50%) gray color, all areas drove at the same speed. After a short time, those ions are free again; the full screen of 128(50%) gray color can easily expose any display bias.
If you have any problems with the TFT LCD screen, please contact us at any time.
