Reflection Handling Isn't Just About A TV Being Matte Or Glossy

Summary

When we began redeveloping our reflections testing suite, we anticipated clear, binary results between matte and glossy displays due to their distinct ways of managing reflections. Matte screens are known for their excellent reflection handling capabilities, notably how they reduce glare compared to glossy screens. Generally, this is what we think of when we think of reflection handling, but it's far from all there is to it.

The more TVs we tested, the more we noticed an interesting trend. The best TVs with glossy screens performed very similarly in our tests to the Hisense Canvas, a matte model, in terms of the intensity of light reflected off its screen, meaning that they reduced glare nearly as effectively. Moreover, these glossy TVs also performed significantly better at something else: black level raise. This impacts every matte TV we've tested to a larger extent than any of the glossy models we've had in our lab and has real consequences on your viewing experience in bright environments.

But while glossy TVs were measured as having the best black levels, their handling of direct reflections had the wildest variations we've seen in our newly developed test, and there was a high correlation between sticker price and performance.

To summarize our findings, when it comes to a TV's reflection handling, there's more to it than simply choosing between a matte or a glossy finish. There are tradeoffs involved no matter which product you choose. With this article, we want to clarify these tradeoffs so you have all the information you need to find the best TV for your needs and viewing environment.

Screen Finish Is Only One Piece Of The Reflections Puzzle

Our newly developed direct reflections test uses a ring light and camera setup, with the camera centered in the ring light. By capturing standardized images of TV screens reflecting the light and processing them through custom software, we measure reflection intensity in our testing setup.

Our initial findings were predictable: by measuring the peak of the reflection intensity, we found that glossy screens create strong mirror-like reflections, while matte screens diffuse reflections over a larger area, reducing their intensity. This distinction is evident in the results of the Hisense CanvasTV QLED 2024, a lifestyle TV with a matte screen, compared to the LG C4 OLED, a mid-range OLED with a glossy screen. The LG C4 reflects our ring light setup in a sharp, mirror-like fashion, while the Hisense Canvas produces a dimmer, more diffused haze spread across a larger area.

By calculating the area under the curve of the direct reflection intensity graph, we can also calculate the total reflected light captured during our test, while centered in front of the screen. The area under the curve captures all components of reflections (direct, indirect, and haze), and offers a comprehensive measurement of all light reflected off the screen.

While it measures all light reflected off the screen, this test doesn't provide discrete values for the peak of the reflection intensity nor the black level raise of the display, which is why it should be used in combination with the other reflection tests (direct reflections & ambient black level raise) to determine what is the best TV for a specific setup. This is because a TV having a great overall score for total reflected light doesn't necessarily mean the TV is a top performer for the distracting glare from direct reflections. A prime example is the Hisense 75U8N, which performs very well for total reflection intensity but is otherwise an average performer when it comes to direct reflections.

As we kept developing our new direct reflections test, we found that some high-end TVs with glossy screens returned nearly as little direct reflection intensity as the Hisense Canvas, despite their glossy finishes producing mirror-like reflections instead of spreading the light. This unexpected result suggested that these TVs could perform well in environments with direct light, presenting a compelling alternative to matte displays.

This underscores an important insight: there really is more to reflection handling than just the screen finish. As you can see from the top six TVs tested for direct reflections so far, the difference between the peak reflection intensity of the worst matte TV and the best glossy one is a mere 1.6%. While they visually appear very different due to the way the matte Hisense Canvas diffuses the light, the intensity of the reflected light isn't too different.

Nevertheless, while matte screens are effective in managing direct reflections, they do so by spreading light across a wide area, producing a tell-tale "single" humped graph as opposed to the dual peaks we see from glossy screens. This diffusion has a downside: it elevates black levels across a significant area of the screen, reducing the perceived contrast and diminishing the richness of dark colors. We call this phenomenon black level raise. Both ambient light and the scatter of light from specular reflections on the screen's surface (haze) cause black level raise.

We developed a dedicated ambient black level raise test to evaluate this phenomenon as part of our updated reflection testing methodology. This test isolates the effects of indirect reflections and haze—those that are diffused rather than mirror-like. For the test, we position a ring light at a calculated distance from the TV screen to create indirect, diffused illumination at the center of the ring light's reflection. Using a colorimeter centered within the ring light, we measure the increase in black levels that would be caused by equivalent ambient illumination.

The Relationship Between Black Levels & Direct Reflection Handling

In general, there's an inverse relationship between a TV's direct reflection handling ability and whether its black levels raise with the presence of ambient light. This becomes very intuitive when we see the Hisense Canvas compared to the LG C4.

The more mirror-like a reflection coming from a TV is, the less the TV diffuses that light and the less the black levels raise. Why, then, do some TVs following this rule have what appear to be horrendous black levels in bright environments?

Is It Black Level Raise Or Bad Direct Reflection Handling?

The Sony BRAVIA 3 effectively showcases the relationship between direct reflection handling and black level raise described above. This TV has some of the worst direct reflection handling we've tested with our new reflections testing suite so far, yet it simultaneously achieves among the best black level raise performance within the same TV group.

However, if we take a closer look at its bright room reflections picture, we notice that something is off—why does the display look so bright?

What's going on is that the Sony BRAVIA 3 is so bad at handling direct reflections that any surface that isn't dark in front of the TV will be reflected off of its screen. In this case, ambient light in our testing room is reflected off of the white wall in front of the TV, and this light is then reflected back toward the viewer by the TV's highly reflective display. This effectively ruins the possibility of having low perceived black levels in such an environment. So, while this TV can exhibit great black level raise performance, you're unlikely to benefit from it unless your TV is sitting in front of a low reflective black wall.

Circular Polarizers Improve Black Levels Without Compromising Direct Reflections

There is an exception to the inverse relationship we found between black level raise and direct reflection performance: TVs with WOLED panels. By design, these TVs feature a circular polarizer in their screen. This component is necessary because WOLED panels are bottom-emissive and built on a metal plate. The circular polarizer prevents light from reflecting back toward the viewer off the metal backplate. This design ensures that the TVs don't raise their black levels or compromise their direct reflection handling performance. The figure below shows a schematic of how circular polarizers work in WOLED panels. The light that isn't reflected off the panel's surface and goes into the panel is first linearly polarized. Then, a reversed quarter-wave plate (r-QWP) circularly polarizes it, which makes reflections go from color to neutral black in WOLED TVs.

However, even with a polarizer, the screen finish and other pieces of hardware still play a significant role in how a TV manages direct reflections. TVs with WOLED panels are particularly interesting because they sometimes include a micro-lens array (MLA) layer in their panels to boost brightness, like in the case of the LG G4 and Panasonic Z95A. While it benefits brightness output, the MLA layer appears to scatter incoming light slightly, negatively affecting their black level raise performance compared to other WOLEDs without the MLA layer.

Are circular polarizers the be-all and end-all of great reflection handling? They definitely have a positive impact, but there are trade-offs. While the presence of a circular polarizer generally improves an OLED TV's overall reflection-handling capabilities, there are notable downsides. These polarizers significantly reduce the TV's brightness output by about ~50%, which requires compensation from its self-emissive OLED layer. Beyond production costs, this is the major technical drawback of this solution.

Aligning Our Reflection Testing With The At-Home Experience

During testing, we found that black level raise impacts more than just black levels—they also affect how the viewer perceives colors, especially low-luminance colors (e.g., dark shades). This impacts color representation when viewing TVs at home in bright environments.

Since people usually use TVs at or near their highest brightness setting in bright environments, we decided to test for ambient color saturation while setting TVs at their highest brightness level in our recommended picture settings. We wanted to evaluate the impact reflection handling has on a TV's perceived color output at these settings, so we used our ring light to generate illuminance on the screen and used our colorimeter to evaluate the perceived color output.

We found that TVs that are worse at mitigating the effects of black level raise extend that to their low-luminance colors as well.

For our test, we measure color saturation with the televisions at their maximum brightness setting, at ambient illumination levels of 0 (baseline), 1000 & 3000 lux, and score based on the results at 1000 lux, which is our approximation of a bright daytime viewing environment (Engineering Toolbox provides practical outdoor and indoor illumination level examples in lux). Some TV models exhibited behavior different from what we had initially expected. For example, the Samsung S95D OLED is prone to black level raise from ambient light due to its matte screen. However, it still outputs noticeably more saturated colors in bright viewing environments than counterparts like the LG G4, which has less black level raise.

But why is this? The Samsung S95D OLED outputs a significantly larger color volume than the LG G4 OLED. Below are results from our development phase showing the measured SDR color volume of both TVs at their maximum brightness level with no lights in the room (baseline measurement) and with our ring light set to its highest power setting.

We can see that colors are still more saturated on the S95D even in this extreme illuminance scenario, even though they desaturate more in absolute terms than those on the LG due to the TV's increased black level raise. It's worth mentioning that the impact of ambient light on color saturation overwhelmingly impacts low-luminance colors as they are easily washed away by black level raise, which we can see in the example below of the LG G4's desaturation at low color lightness levels.

Our updated direct reflections and ambient black level raise tests look solely at the physical components of the screen and their impact on reflection performance. The ambient color saturation test is our first step in evaluating TV reflections holistically, combining a TV's color volume with its black level raise. The impact of brightness and effective contrast is still to be explored. A TV may excel at both direct reflection handling and mitigating the effects of black level raise but still fall short in very bright environments if it's too dim. This was a common issue on first-generation OLEDs, which lacked the sufficient brightness to offer a great experience in bright living rooms.

Conclusion

As discussed throughout this article, a TV's reflection handling isn't just about whether it has a glossy or a matte display. The inverse relationship between direct reflections and black level raise on most TVs means that tradeoffs are involved and that considering your viewing environment and its lighting is important when buying a new TV. The notable exception to this relationship, WOLEDs, show that the screen finish itself is just part of the reflection equation; hardware below the surface, like polarizers, can significantly benefit a TV's overall reflection handling capabilities.

We also saw how black level raise from ambient light combined with haze from reflections can have a significant impact on color saturation, especially for darker shades of colors. Our new testing suite is just scratching the surface of what is needed to make the most comprehensive buying recommendations for bright room TVs. As part of our next TV test bench update, we're already planning a review and rework of our brightness testing. This is because, for very bright rooms, it's not only a TV's reflection handling but also its brightness output that can make or break the viewing experience for most content, although high brightness won't necessarily save dark scenes like the infamous Game of Thrones episode, The Long Night.

We look forward to improving our existing tests and exploring new ideas to expand our testing to offer the most comprehensive TV evaluations possible, so don't hesitate to write your suggestions and feedback in the comments section of this article!