TFT LCD FAQ
A comprehensive frequent asked questions for TFT LCD, covering basic knowledge.
1. What is TFT LCD Size?
TFT LCD size refers to the diagonal measurement of the display area, typically in inches (e.g., 5", 10.1", 15").
Choose a size based on viewing distance, portability, and application requirements (e.g., compact vs. immersive viewing).
2. What is TFT LCD resolution?
A screen's resolution refers to number of pixels on a TFT display, usually in X by Y format. Resolution determines pixel density and image clarity.
Higher resolutions like 1920x1080 (FHD) or 2560x2048 (QSXGA) provide sharper visuals, ideal for detailed tasks (e.g., medical imaging). Lower resolutions (e.g., 800x480) are cost-effective for basic displays.
3. What are common TFT LCD interfaces?
Parallel RGB: Uses multiple data lines for fast communication, ideal for embedded systems.
LVDS/MIPI DSI: Low-voltage differential signaling (LVDS) or Mobile Industry Processor Interface (MIPI) for high-speed data transfer in modern devices.
SPI/I²C: Serial interfaces for small displays with limited data needs (e.g., low-cost IoT screens).
HDMI/VGA/DisplayPort: Standard for consumer electronics like monitors and TVs.
4. What is backlight in LCD?
TFT LCD panel doesn't emit light. A backlight luminates the LCD panel. Most TFT LCDs use energy-efficient LED.
PWM (pulse-width modulation) or DC dimming adjusts backlight intensity.
5. What is luminance, and why is it important?
Luminance indicates a TFT LCD's brightness, is measured in nits (cd/m²). High luminance (e.g., 800–1000 cd/m² ) ensures visibility in bright environments, critical for outdoor displays.
6. How is contrast ratio defined in TFT LCDs?
Contrast ratio measures the difference between the brightest white and darkest black. Higher ratios improve depth and detail in dark scenes. Ratios like 1000:1 or 3000:1 indicate deeper blacks and better image depth.
You probably heard the term "dynamic contrast ratio". Static ratios are fixed; dynamic ratios adjust based on content (often marketing-driven).
7. What is response time, and how does it affect performance?
Time taken for a pixel to transition between colors (e.g., gray-to-gray: 25ms). High-end TFT LCDs achieve 1ms response times , reducing motion blur for gaming or fast-moving content.
8. How does refresh rate influence display quality?
Refresh rate (Hz) determines how often the screen updates per second. Higher rates (e.g., 120Hz/144Hz ) improve motion smoothness, while 60Hz suffices for general use.
9. What defines the viewing angle of a TFT LCD?
IPS panels provide 178° viewing angles with minimal color shift, whereas TN panels have narrower angles . This is critical for collaborative or multi-user setups.
10. What is color depth, and how is it measured?
Color depth (bits per pixel) defines the number of displayable colors. High-end TFT LCDs support 16.7 million colors (8-bit) for vibrant, true-to-life visuals.
11. Gamut
The range of colors that a display can reproduce. A larger color gamut indicates that a display can show a wider range of colors, which is essential for accurate color reproduction, especially in professional applications like photography and design.
12. Pixel
The smallest unit of a display screen, typically made up of red, green, and blue sub-pixels that create full-color images when combined. The resolution of a display is determined by the number of pixels it contains.