In various commercial displays, high brightness is crucial for ensuring clear image visibility, especially in bright light environments. Insufficient brightness in displays directly leads to decreased visibility, severely impacting the user experience.
Traditional methods for improving brightness involve increasing LED chip density, but this approach has the following drawbacks:
○Physical Space: The LED panel area becomes saturated, leaving no room for further placement.
○Power Consumption Outages: Overall power consumption increases, putting pressure on power supply and battery life.
○Heat Dissipation Failure: Sustained high temperatures accelerate the aging of optical films.
Due to the limitations of increasing LED chip density, optical brightness enhancement film technology has become one of the effective ways to improve brightness, with DBEF film showing particularly outstanding performance.
About DBEF
DBEF, short for Brightness Enhancement Film, is a multi-layered reflective polarizing film developed by optical experts.
Unlike ordinary brightness enhancement films (such as BEF), DBEF optical film focuses on optimizing and recovering polarized light. In the backlight modules of commercial displays, DBEF is typically placed between the diffuser and polarizer, acting as a connector between the two. Through its precise multi-layered structure, it converts wasted light into usable output, significantly improving overall brightness.
Compared to BEF (Brightness Enhancement Film), which primarily refracts and focuses light through a prism structure, a single sheet can improve brightness by 40%-60%, with even better results when two sheets are used together.
However, DBEF goes a step further, combining reflective polarization technology, making it suitable for commercial scenarios with higher requirements for brightness and energy efficiency. DBEF ensures clear visibility of the image in strong light environments without increasing hardware costs.
How does DBEF work?
The core of DBEF lies in its handling of polarized light. In standard LCD backlight systems, the light emitted by the light source is unpolarized. When it passes through the lower polarizer, approximately half of the light (P2 polarized light) is absorbed and wasted, leading to low efficiency.
The DBEF polarizer cleverly solves this problem: it allows one type of polarized light (P1) to pass through directly while reflecting P2 light back into the backlight. This reflected light is repeatedly scattered and converted within the backlight cavity, eventually partially converting back into P1 light for reuse. This recycling mechanism can improve luminous efficiency by approximately 1.8 to 2 times.
Furthermore, DBEF is equipped with a diffused surface design, which not only enhances brightness but also improves visual uniformity, avoiding light spots or unevenness.
This is particularly useful in commercial displays because it can be combined with other optical films such as BEF or ESR (Enhanced Reflective Film) to form customized solutions.
Common Types of DBEF
Depending on the application scenario, DBEF has several variants to adapt to the diverse needs of commercial displays:
①DBEF-M: Surface-coated diffusion layer prevents unwanted contact with other optical materials. When combined with BEF, it helps reduce moiré patterns (reflection interference), suitable for indoor and outdoor displays with stringent image quality requirements.
②DBEF-D: Double-sided bonded diffusion sheet, improving the mechanical strength and thermal stability of the film, suitable for high-temperature or vibration environments, such as automotive commercial displays.
③DBEF-D200: Similar in structure to DBEF-D, but only 200μm thick, thinner and lighter, facilitating integration into compact devices without compromising performance.
| Product Features | DBEF | DBEF-M | DBEF+xTBEF | |
| Axial Brightness Gain | 1.62 | 1.59 | 2.51 | |
|
Viewing angle (1/2 brightness) |
Horizontal | 113 | 113 | 58 |
| Vertical | 99 | 98 | 50 | |
| Haze | - | 29% | - | |
| Rated Thickness | 132um | 132um | - | |
The position of DBEF in the backlight structure of commercial displays:
Advantages of DBEF for Commercial Displays
For commercial display manufacturers, the biggest attraction of DBEF lies in its "plug-and-play" nature. Without altering the existing structure or increasing power consumption, simply adding a DBEF film can meet customers' needs for high-brightness screens.
This is a significant advantage in a highly competitive market: for example, POS machines need to maintain readability under direct sunlight. DBEF helps boost brightness from standard levels while keeping power consumption stable, preventing overheating.
From an energy efficiency perspective, DBEF reduces light source waste, indirectly lowering operating costs. Imagine if a large commercial screen relied on more LEDs for brightness; not only would the initial investment be high, but it would also increase electricity bills and maintenance burdens.
DBEF bypasses these problems through optical optimization, providing a sustainable solution. At the same time, its high visual quality ensures distortion-free images, making it suitable for professional fields such as medical displays and industrial monitoring.
Precautions for using DBEF
While the DBEF optical film is powerful, proper installation and calibration are crucial. A key point is that the transmission axis of the DBEF must be parallel and aligned with the transmission axis of the rear polarizer. This needs to be verified through a pre-assembly lighting test (FOG calibration); otherwise, brightness loss or color cast may occur.
When disassembling the backlight module, pay attention to the position of the DBEF film. It is usually located above the diffuser layer for easy identification.
Additionally, when testing backlight brightness alone, the value may be slightly lower after adding the DBEF. The actual brightness needs to be tested in conjunction with the module.
Manufacturers are advised to conduct extensive optoelectronic testing during the prototype stage to ensure compatibility.
Conclusion
In an era where commercial displays strive for higher brightness and lower energy consumption, DBEF is undoubtedly the optimal solution in the field of optics.
It not only addresses the pain points of outdoor applications but also provides a flexible and reliable upgrade path for display devices. If you are considering optimizing your product line, consider exploring DBEF's integrated solutions-it can make your displays stand out in the market.
If you are looking to deploy a high-brightness digital display solution, please contact us to discuss how to apply DBEF to your project.
