Sunlight Readable TFT LCD: Transflective TFT vs. High Brightness TFT

Sunlight Readable TFT LCD displays are including transflective tft LCD and High Brightness TFT LCD, both high brightness tft LCD (a kind of transmissive display) and transflective lcd are viewable under sunlight conditions, however, there are still many things are different for transmissive high brightness tft and transflective tft lcd. which one is better display for sunlight readability? let's see the comparison in this article.

1.  What is Transmissive TFT,High Brightness TFT and Transflective TFT LCD

• Transmissive TFT LCD is the tft lcd panel in transmissive mode, the display light has to rely on the backlight on the rear side of tft panel. the brightness of transmissive display is depended on the brightness of backlight and transmissive ratio of tft panel.
• High brightness TFT LCD is a kind of transmissive LCD display, it use high brightness backlight and transmissive TFT technology to compete high brightness sunlight.
• Transflective TFT LCD has a reflector layer inside tft lcd cell, that is in front of the backlight, The incoming light is reflected and reused to illuminate tft display. While tranditional transflective LCD,its reflector is on polarizer.

• Transflective TFT LCD have both "transmissive" and "reflective" modes. Both display modes work together for enhancing performance.
• -- In darker environments, the “transmissive” mode is dominant with emissions from the display’s backlight.
• -- In bright environments, the “reflective” mode of the display is more dominant through reflectance from the internal mirror structure.

Transflective TFT LCD displays screen become more and more popular because the demand of display working in daylight environments and direct sunlight, it is a good solution for daylight readable display.

2. Advantages of Transflective screen:

The advantage of transflective display TFT modules is power saving compared to traditional “transmissive- only” displays.

• Transflective lcd display are perfectly readable under almost any ambient light conditions. because transflective screen combines the advantages of transmissive and reflective lcd displays.
• Transflective LCD are very energy efficient, making them ideal for battery powered devices and mobile applications. By using a transflective screen, we can save power by reducing or turning off the display’s backlight during bright environments because the “reflective” mode is dominant.

Transflective TFT become more popular since the demand of requiring good performance in bright environments and direct sunlight. so that the transflective TFT displays are perfectly readable under almost any ambient light conditions.

3. Key Characters of Transflective TFT LCD: Reflective Ratio

If using transflective TFT LCD, the reflective rate is a key character for transflective TFT LCD. Higher transflective rate means better display performance in outdoor display, and it is better for power saving.

• A True Transflective TFT LCD, its reflect layer is inside TFT cell, the reflective ratio of a true transflective TFT LCD is up to 6%. The higher reflective ratio means lower power consumption, and better display performance for sunlight readable display.

There are some fake transflective TFT LCD that only with 2% reflective rate. the 2% reflective ratio is too low to say it is real transflective tft lcd display.  What it is main different between true transflective TFT and fake transflective TFT LCD. The secret is on the polarizer of LCD.

• A Fake Transflective TFT LCD are only using transflective polarizers on the backside of transmissive tft lcd, the way that make for tradition monochrome transflective LCD. It is no problem for a monochrome transflective LCD by using transflective polarizer, because monochrome lcd has higher transmittance ratio than TFT LCD panel. While a TFT LCD panel is with color filter, the color filter reduce the transmittance ratio of TFT panel, it lead to the reflective ratio is only 2% by using transflective polarizer.

4. Types of Transflective LCD : Color Transflective TFT and Monochrome Transflective LCD

Beside the color filter in side tft panel, the main different of transflective TFT LCD and tranditional monochrome  transflective LCD is the reflecitve layer location.

• Monochrome Transflective LCD: The transflective layer is located on rear polarizer,
• Transflective TFT LCD (colorful): it reflector is located inside the tft cell, the inside reflector is with higher efficient reflector and less light reflection to the display.

5. The cost of transflect tft lcd vs. high brightness tft lcd display:

The transflective TFT LCD is expensive than high brightness TFT LCD, its cost is double than high brightness, because transflective TFT LCD is rare, and inner transflect layer is much costly and complicate in TFT panel production.

6. Indoor vs Outdoor Display Performance: High Brightness TFT vs Transflective LCD

• Indoor Use: High-brightness TFT LCDs win for superior brightness.
• Outdoor Use: Both high-brightness (800–1000 nits) and transflective LCDs work well in sunlight

6.1  Indoor Display Performance

High-brightness TFT LCDs deliver superior display performance in indoor environments due to their high transmittance rate and powerful backlight system. These displays produce higher luminance compared to ambient indoor lighting, ensuring excellent visibility and color accuracy.

In contrast, transflective TFT LCDs rely partially on ambient light for illumination. Since indoor lighting is typically weaker, the display's brightness depends more on its backlight. However, because transflective LCDs have a lower transmittance rate, their surface luminance is reduced in indoor settings.

Conclusion for Indoor Use:

High-brightness TFT LCDs outperform transflective LCDs in indoor environments due to their superior brightness and clarity.

6.2  Outdoor Display Performance

In direct sunlight, displays require extremely high surface luminance to remain readable. There are two effective solutions:

6.2.1. High-Brightness TFT LCD (800–1000 nits)

• Designed for sunlight readability under direct sunlight
• Provides 800–1000 nits brightness to compete with strong ambient light
• Ensures sharp visibility even under bright outdoor conditions

6.2.2. Transflective TFT LCD

• Uses a reflective layer to harness ambient light
• The brighter the sunlight, the more reflective luminance is generated
• Offers better color performance than standard transmissive LCDs at the same backlight level
• Typical reflectance rates range from 2% to 7% (e.g., 2% reflectance under 10,000 lux sunlight adds ~200 nits to the display's brightness)

6.3  Suggestion for brightness and ambient condition:

Ambient Condition	Ambient  Brightness	Recommended LCD  Display Brightness
Dark environment	Less than 50 nits	Up to 50 nits
Indoor daylight	Less than 500 nits	Can be turn down to 200 nits
Indoor Lighting	Less than 1000 nits	Up to 300 nits
Overcast sky, without sky	1000 to 3000 nits	300 - 500 nits
Thin bright overcast sky, indirect sunlight, shadows are visible	3000 to 7000 nits	500 - 800 nits
Directly sunlight in blue sky, shadow are clearly	7,000 to 10,000 nits	800 - 1000 nits

7. Summary

• Transflective TFT LCD is fit to the device in outdoor, and for the device is sensitive for power saving, but transflective TFT LCD is more expensive than high brightness TFT.
• High brightness TFT is also fit for outdoor application, but it is fit for the device that is not sensitive for power saving, and it is cheaper than transflective TFT LCD.

8. What Maclight can do for our customers:

Maclight could provide both high brightness TFT Display and transflective tft display solutions. All our sunlight readable display TFT models are also available with resistive touch panel or capacitive touch solutons.

Maclight's transmissive high brightness TFT LCD displays are up to 1000+ nits.

Maclight transflective TFT LCDs are with high reflective ratio, they have excellent sunlight readable performance and better power saving property, perfect selection for outdoor daylight applications.

If you would like to know more about Sunlight readable tft display, welcome to contact us at : [email protected].