What is the halo effect?
Halo effect or FALD blooming refers to the enhanced apparent brightness of an object against a bright background.
The term FALD (Full Array Local Dimming) is generally used to describe the technology that attempts to merge local dimming with full array backlight systems for LCD televisions. FALD blooming tends to have more of an oddball identifier rather than a perceived intensity increase, with subjects describing the size and depth of the bloom.
A similar effect is often seen in photographs where there is too much contrast or saturation applied to one section of the image, such as a sun flare in photos taken directly into light sources.
Halo effects are prominent in partially specified images that show an outline or partial picture and expect reasonable familiarity on the part of viewers (meaning we don't need complete information). They may also occur with text and icons within computer interfaces.
Where did it come from?
The term halo effect was first introduced by the psychologist Edward Chace Tolman to denote a cognitive bias in his experiments on rats learning a maze. The rat's anticipation of food at the goal location made it tend to circle there more often than necessary as if its path were magnetically pulled toward that point. In ambiguous visual displays, objects with similar shapes and colors tend to be grouped together visually even though they may not belong semantically.
These kinds of grouping biases can cause misclassifications or false positives – for example, a line drawing of a car might contain only 10% of the elements that make up a real car – yet people easily identify it as a car due to other parts being present.
The halo effect is often induced through specific characteristics of an image, which are used to draw attention. The halo effect is not only limited to visual perception but also applies to other sensory systems.
For instance, a product that stimulates all senses at once can attract attention more deeply than one that stimulates only one sense because the stimuli provided by the different senses interact and produce greater overall effects.
LED and OLED displays
Both are susceptible to halos because the lighting elements are arranged in a grid fashion. Because of this these LED TVs are known as edge-lit displays. The LEDs along the edges or 'curtain' of the panel shine through the individual pixels, thereby illuminating them only on one side, resulting in light blooming.
It's essentially large TV panels equipped with small diodes that allow for localized control of luminance levels - unlike standard backlights which distribute power evenly across all illuminated areas of the display, giving OLED TVs their unique picture quality. These diodes are placed on individual pixels of the display.
OLED TVs are designed differently, with different goals in mind. Because all colors are produced by each individual pixel, LEDs have more latitude in producing color gradations. Blooms are even subtler on OLED displays because they only light up when needed. That's why screens reproduced using Pixel Contrast Booster look so deep and natural.
All TV monitors are susceptible to halos because all monitor displays are made up of what are called "picture elements", or pixels.
As an example, a normal computer LCD monitor has about 300 pixels per inch, while a standard definition television has closer to 330 PPI (pixels per inch), but brightness and color capabilities vary. The greater the PPI count, the more accurate the picture will be because displays with higher PPI counts can accurately reproduce fine details.
The halo effect is most prominent when changing any part of a picture - for instance, adjusting contrast or brightness will make blooming more visible. It becomes less apparent if the image stays static.
Because OLEDs do not have filters to remove this light, they are capable of showing pure black, with no light bleed-through from other colors. They also offer wider viewing angles - where LCDs can lose luminance quickly as you move away from the center, OLEDs stay perfectly bright right off the bat.
The result is an experience closer to what it would be like in real life. In fact, OLED TVs come the closest among all current-generation displays to offering true blacks and infinite contrast.
Local dimming technology
is slowly marching toward full-array LED arrays (FALD), which allow for more precise control of pixel brightness. Full array backlighting allows the TV to produce very deep black levels, and limit blooming artifacts.
Another method of eliminating blooming effects in TVs is local area dimming, which adjusts the luminosity level on a small section-by-section basis so that variations in intensity are not easily visible. With this technology, each OLED emits just enough light for the required luminescence level, creating less intrusive halos."
Edge-lit displays still suffer from blooming because there aren't any seams between different sections along the edge - instead, different lighting channels overlap to create an even spread across large areas. This means that when displaying a pure black screen, the entire display is illuminated - not just the pixels that need to be lit.
Ambient light obscures FALD blooming
However, for LCDs, even the best local dimming on the market today does produce some degree of blooming or halo-type artifacts that are most noticeable when contrasting elements are present in an image.
As a result, this is why it has been difficult to achieve perfect blacks and infinite contrast ratios with LED or LCD televisions. The problem stems from the nature of how we see objects - we need to see them surrounded by darkness in order to perceive their shape and depth properly (i.e., as we would in real life).
With current displays, you're actually seeing halos around these areas because there's light bleeding through from other of the screen. This compromises the inky blacks that are so essential to the HDR experience, which is where FALD comes in.
FALD keeps contrast high even with bright ambiance
FALD overcomes this drawback by minimizing blooming and halo effects by individually controlling LEDs within the display. Advanced algorithms help ensure that they only fire when necessary, i.e., during low-light scenes or when displaying black levels (which don't require backlighting).
The result is what looks like an infinite dynamic range picture with perfect blacks - no matter what's happening on screen. This helps increase immersion for your favorite films and TV shows, especially when you're watching something dark or gritty; it's more akin to seeing these images in real life than ever before.
FALD solutions for gaming computers
FALD is also an important technology for gaming monitors. If you're playing in a room with lights on, it can be difficult to see enemies sneaking up on you or spot dark areas in the game; FALD ensures that these details are fully visible at all times without washing out what's happening around them.
Both OLEDs and LCDs work by using individual pixels (i.e., tiny light emitters) that change their brightness in response to optical impulses that they receive. To display 96% of the NTSC color space, TVs need to offer more than half a million separate colors.
This is where quantum dots come in - quantum dots enable this high color fidelity by helping TVs produce much finer gradations within the range defined by the NTSC standard.
Quantum dot solutions
This is why quantum dots are so important for TVs - the smaller the pixels on your TV, the more accurate it can be in terms of color reproduction. Quantum dots help to improve color accuracy by confining their light emission within a small, "safe" zone that doesn't overlap with other colors on the screen.
This increases the number of available colors substantially, while also limiting cross-talk between adjacent hues. The result is crisper images with more depth and realism, not to mention more vibrant primary colors.
Movement resolution is one of several factors that determine how clear fast-paced action appears on your TV screen. It's often measured in either lines or hertz (Hz), with lines referring to the number of distinct images that can be displayed per second. The greater this figure, the smoother the picture will seem when objects are in motion.
When talking about TVs and gaming monitors, a lot of people get confused between these two metrics for measuring movement resolution—in fact, most manufacturers don't make it easy to grasp what they actually mean.
This is why we want to clarify how each term works and its importance for your particular needs because these terms measure slightly different things. To do so, we need to take a moment to explain the refresh rate.
Bottom line
The halo effect is especially noticeable in dark scenes where light tends to "bleed" through darker areas on the screen, compromising black levels.
This is where FALD comes into play, as it minimizes blooming and halo effects by individually controlling LEDs within the display through advanced algorithms that ensure they only fire when necessary - this results in perfect blacks even with lit rooms/ambiance.