What is Transflective TFT Display

LCD display have three display modes: that is transmissive display, transflective display and reflective display mode, regards color TFT LCD display, there are only transmissive TFT display and transflective tft display mode. Transflective TFT LCD is a good solution for Sunlight readable tft serial when in outdoor application. Since a regular transmissive TFT have to be enhanced its brightness as high as possible for sunlight readable purpose. However, high brightness TFT and backlight would lead to high current and high power consumption for high brightness LCD screen.Could you image that your display’s battery power would be ended when in outdoor application, while for transflective TFT LCD display, its power consumption would be more lower than regular brightness tft lcd module, under the stronger sunlight directly, the transflective TFT LCD even no need the backlight to watch, so it could support longer time working without power charge.

Therefore, transflective TFT LCD solution is a good power saving solution for outdoor sunlight readable lcd display.

The construction of transflective lcd screen:

As you could see from the transflective TFT LCD structurer,

there is a reflective mirror layer on the rearside of TFT LCD glass, and there are lots of holes on the mirror layer, the function of the holes are for light transmittance, so the reflective mirror layer is combined the function of light reflective and light transmittance.  Therefore, transflective TFT LCD display could be combined the function of transmissive LCD and reflective LCD display. When in indoor display, with lower light source from environments, transflective TFT would need the backlight from the backside of LCD, because TFT LCD is passive display, it can not emit light from itself as the way of OLED display, so it is necessary to need the light source from environment,  such as use backlight on the backside of TFT LCD. While in outdoor application, the strong light source could be from ambient, such as sunlight, even no need the backlight, if re-use the light source from inner light inside the transflective TFT, it would be a good solution for power saving to transflective TFT LCD, because no need the light from backlight on TFT LCD module.

Power consumption of transmissive high brightness TFT Vs. transflective TFT LCD module

The backlight current is a big power consumption source for a TFT LCD display, a regular LED chips would need around 20mA ,3.0V per chip, as a small size TFT LCD module, such 2.4” or 2.8” TFT LCD module, 4~6 led chips are regular LED quantity to small sizes of TFT LCD, while if for 7 inch tft LCD, the regular LED chips would be around 27 LED chips for getting regular brightness on 250 nits. Therefore, if we need a high brightness TFT LCD module that used in outdoor display, such as more than 500 nits or 1000 nits LCD, the led chips quantity might be double than regular brightness TFT LCD module. That means a sunlight readable TFT LCD module in high brightness with transmissive display type, power current would be more than 100mA~300mA, it would lead to very high power consumption in a high brightness transmissive TFT LCD for outdoor application. While if we choose transflective TFT LCD, because transflective TFT LCD have the reflective layer inside its color filter, it could reflect the light from sunlight in TFT LCD display module internal, so if under strong sunlight, we could see the display content even without backlight. Enn…,without the backlight, that would be a good source to power saving, that is the reason why we like to choose transflective TFT LCD for outdoor display application.

How transflective TFT LCD screen working:

How the transflective screen to realize the transmissive and reflective display effect in one display?

The secret is on the color filter. A reflective layer is on the rear of color filter, when the sunlight go into the transflective TFT LCD module, the reflective layer would reflect part of light back into display, so the stronger sunlight would make a better reflective display. But if without stronger sunlight, the backlight for transmissive display is necessary. As you could see the color filter picture, there are some hole on each R, G or B unit, the hole is for light transmit when in transmissive mode, we call “open ratio” to the transflective TFT screen. The higher open ratio means higher transmissive ratio to a transflective TFT, in the meantime, lower open ratio, means lower transmissive ratio and higher refletive ratio to the transflective TFT LCD module. The open ratio designed is up to the application and the environment of the sunlight readable TFT LCD module.

Maclight display specializes in sunlight readable display, we have wide range of transflective TFT LCDs for sunlight readable display application.

Please find more transflective tft lcd in https://www.szmaclight.com/sunlight-readable-tft.html.