We absolutely loved the Neewer RGB62 in testing. This compact portable RGB LED is super affordable at $26 and, as an RGB light, isn’t limited to only yellow or white like many ring lights (although it does have a bi-color mode with a very wide 2500K-8500K temperature range). It comes with a diffuser to soften the light and has an internal battery so you don’t need to plug it in. It also features four cold shoe mounts to give a wide variety of mounting options — you can mount this panel on top of your camera, then mount 3 more accessories to the light itself, or you can daisy chain several of these lights to make a more powerful lighting setup. You can also control it with the Neewer app which allows you to fully control the lighting, as well as assigning a range of effects, such as music synchronization. It also comes with a magnetic back, so you can simply clip it to anything metal without the need for a light stand.

Although this inexpensive ring light has a barebones design and feature set, it can be used on various mobile devices, including most phones and tablets, as well as on laptops. The model also lets you adjust the strength of the light’s brightness by setting it to low, normal or high.

Using PWM (pulse-width modulation, a technology where the intensity of the LEDs are kept constant, but the brightness adjustment is achieved by varying a time interval of flashing these constant light intensity light sources[26]), the backlight is dimmed to the brightest color that appears on the screen while simultaneously boosting the LCD contrast to the maximum achievable levels

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For a non-ELP backlight to produce even lighting, which is critical for displays, the light is first passed through a lightguide (Light guide plate, LGP) - a specially designed layer of plastic that diffuses the light through a series of unevenly spaced bumps. The density of bumps increases further away from the light source according to a diffusion equation. The diffused light then travels to either side of the diffuser; the front faces the actual LCD panel, the back has a reflector to guide otherwise wasted light back toward the LCD panel. The reflector is sometimes made of aluminum foil or a simple white-pigmented surface.

FeaturesDo you need a ring that lets you adjust the light’s color temperature or brightness? Or do you need the option of powering the ring light either by an AC adapter or using batteries?

LED BacklightStrips

A review of some early backlighting schemes for LCDs is given in a report Engineering and Technology History by Peter J. Wild.[2]

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A backlight is a form of illumination used in liquid-crystal displays (LCDs) that provides illumination from the back or side of a display panel. LCDs do not produce light by themselves, so they need illumination (ambient light or a special light source) to produce a visible image. Backlights are often used in smartphones, computer monitors, and LCD televisions. They are used in small displays to increase readability in low light conditions such as in wristwatches.[1] Typical sources of light for backlights include light-emitting diodes (LEDs) and cold cathode fluorescent lamps (CCFLs).

What’s nice about this ring light is that it’s small in size and lightweight, so it will fit into many pocketbooks, or even a jacket pocket. It comes with a USB micro cord, in order to recharge the unit’s battery. The manufacturer claims this ring light has a battery life of 1-5 hours.

LED backlightboard

As a studio light, however, the MS60C is expensive, so if you’re on a tight budget one of the ring lights above will be better suited. This light is aimed more towards burgeoning enthusiasts and serious content creators. It also won’t give you the trademark ring in your eye that you’ll find with actual ring lights, so if you’re shooting beauty content and want the ring light “look” this won’t be for you. Annoyingly, it doesn’t come with a stand or batteries, either, both of which are expensive.

J Gorisse · 2012 · 11 — Wireless transceivers for gigabit-per-second communications. Abstract: This paper presents a state-of-the-art of wireless transceivers providing Gbps data-rate.

LEDTVbacklightstrip Replacement

The best ring lights are a must if you're looking to improve the quality of your videos, whether you're streaming on YouTube or hosting a work Zoom call.

Most will work with either cameras or smartphones (we've got a separate list of the best ring lights for phones if you're specifically interested in that side of things) and they're a great match for one of the best cameras for vlogging. Some also appear among our pick of the best TikTok lights.

If you want to take your lighting to the next level, or you want to shoot more than just to-camera or vlogging content, you might well be better off investing in a proper video light. Look no further than the Neewer MS60C. This portable video LED is super powerful and will allow you to craft professional-looking sets. It’s RGB, so you aren’t limited to just yellow or white, can run off either mains or battery power, and comes with a handle for handheld usage, making it a very flexible and portable tool. It’s also pretty small for a studio light, as it doesn’t need an internal fan. As with other Neewer products, you can control the MS60C fully via Bluetooth through the Neewer app.

LED backlighting in color screens comes in two varieties: white LED backlights and RGB LED backlights.[10] White LEDs are used most often in notebook computers and desktop screens, and make up virtually all mobile LCD screens. A white LED is typically a blue LED with broad spectrum yellow phosphor to result in the emission of white light. However, because the spectral curve peaks at yellow, it is a poor match to the transmission peaks of the red and green color filters of the LCD. This causes the red and green primaries to shift toward yellow, reducing the color gamut of the display.[11] RGB LEDs consist of a red, a blue, and a green LED and can be controlled to produce different color temperatures of white. RGB LEDs for backlighting are found in high end color proofing displays such as the HP DreamColor LP2480zx monitor or selected HP EliteBook notebooks, as well as more recent consumer-grade displays such as Dell's Studio series laptops which have an optional RGB LED display.

The downsides? The onboard controls can take a bit of working out, especially if you’re new to lighting. And while it’s powerful for its size, I’m not sure it’ll function well as a main light if your trying to shoot higher end content for socials or YouTube (unless you daisy chain two or three of them together with the cold show mounts). Still, on its own, a single RGB62 should be more than enough for video calls and would serve as a great secondary light to cast shades of color into the background of your frame.

Polarization vision in vertebrates has been marked with significant controversy over recent decades. In the last decade, however, models from two ...

If you’re looking for a versatile ring light kit that has a professional build quality and provides you with lots of features and options, the Westcott 18-inch Bi-Color LED Ring Light Kit with Batteries and Stand will fit the bill. Westcott has a long history producing top-notch lighting equipment for pros, and is an excellent choice, whether you’re using it for vlogging, live streaming, capturing video or shooting still photos for portraits, food, still life and many other types of genres.

This portable LED kit also comes with a 61-inch light stand, constructed from aluminum alloy, giving it exceptional strength. It also has a 360-degree rotatable smartphone holder, plus a Bluetooth receiver for controlling your ring light remotely. Oh, and it even comes with a handy carrying bag.

Firstly, you'll want to consider whether you want a ring light or a different type of light. Ring lights are the best for vlogging or beauty content, as they're primarily aimed at lighting faces. If you are doing lots of different types of video, one of the best ring light alternatives above might be the better choice for you.

However, for the price, it’s quite a useful selfie light that allows you to set the brightness at three different levels. It can also be used with a variety of devices, including a smartphone or laptop, which can be useful when you have a meeting and want to make the lighting look soft and natural. It’s ideal for those photographers who want to shoot casual selfies or video clips. It can also be controlled wirelessly.

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The use of LED backlights in notebook computers has been growing. Sony has used LED backlights in some of its higher-end slim VAIO notebooks since 2005, and Fujitsu introduced notebooks with LED backlights in 2006. In 2007, Asus, Dell, and Apple introduced LED backlights into some of their notebook models. As of 2008[update], Lenovo has announced LED-backlit notebooks. In October 2008, Apple announced that it would be using LED backlights for all of its notebooks and new 24-inch Apple Cinema Display, and one year later it introduced a new LED iMac, meaning all of Apple's new computer screens became LED-backlit displays. Almost every laptop with a 16:9 display introduced since September 2009 uses LED-backlit panels. This is also the case for most LCD television sets, which are marketed in some countries under the misleading name LED TV, although the image is still generated by an LCD panel.

Much like the Logitech Litra Glow, we like the Elgato Key Light Mini because it offers a different path to illumination as a ring light alternative. Small and light enough to hold in your hand if you need to move and direct its lighting on your on, the Key Light Mini's internal 4000 mAh power supply lasts a while on a single charge (and charged speedily via USB-C in our testing).

Backlights come in many colors. Monochrome LCDs typically have yellow, green, blue, or white backlights, while color displays use white backlights that cover most of the color spectrum.

If the frequency of the pulse-width modulation is too low or the user is very sensitive to flicker, this may cause discomfort and eye-strain, similar to the flicker of CRT displays.[27][28] This can be tested by a user simply by waving a hand or object in front of the screen. If the object appears to have sharply defined edges as it moves, the backlight is strobing on and off at a fairly low frequency. If the object appears blurry, the display either has a continuously illuminated backlight or is operating the backlight at a frequency higher than the brain can perceive. The flicker can be reduced or eliminated by setting the display to full brightness, though this may have a negative impact on image quality and battery life due to increased power consumption.

SizeAdditionally, consider the size of the light: some are quite small and portable, which means you can take them on the road with you; others are larger and heavier, which may weigh you down.

As you might expect from its name, the Rotolight Ultimate Vlogging Kit is designed for content creators making videos or streaming to YouTube, TikTok and Instagram. With that in mind, it comes with a mini tripod that can turn into an extended camera grip: very helpful if you often switch between shooting in a studio and on the go.

RGB LEDs can deliver an enormous color gamut to screens.[12] When using three separate LEDs (additive color) the backlight can produce a color spectrum that closely matches the color filters in the LCD pixels themselves. In this way, the filter passband can be narrowed so that each color component lets only a very narrow band of spectrum through the LCD. This improves the efficiency of the display since less light is blocked when white is displayed. The actual red, green, and blue points can be moved farther out so that the display is capable of reproducing more vivid colors.

To overcome the aforementioned challenges with RGB and white LED backlights an 'advanced remote phosphor' [20] LED technology has been developed by NDF Special Light Products, specifically for high-end and long-life LCD applications such as cockpit displays,[21] air traffic control displays, and medical displays. This technology uses blue pump LEDs in combination with a sheet on which phosphorous luminescent materials are printed for colour conversion. The principle is similar to quantum dots, but the phosphors applied are much more robust than the quantum dot nano-particles for applications that require long lifetime in more demanding operational conditions. Because the phosphor sheet is placed at a distance (remote) of the LED it experiences much less temperature stress than phosphors in white LEDs. As a result, the white point is less dependent on individual LEDs, and degrading of individual LEDs over lifetime, leading to a more homogenous backlight with improved colour consistency and lower lumen depreciation.

The QIAYA selfie ring light is the most lightweight of the products we looked at for this guide. In fact, it’s also compact, enough so that you can easily carry it around in your pocket. Overall, it has a very simple, straightforward design, but doesn’t provide a lot of options when you compare it to more expensive models.

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There are several mounting options, including a tripod ball head, which lets you use a DSLR or mirrorless camera. Plus, you have the ability to mount up to five phones at the same time on this model. And as a nice extra, the back of the light comes in two colors — pink and black.

PriceFirst, consider how much you’re willing to spend. The models in our guide give you rough estimate of the price range of ring lights, which can run as little as $6 or a much as $189. However, there are pricier ring lights available for more professional or specialized uses. For example, some models can cost as much as $500, but are extremely powerful and versatile.

LED BacklightStrip for TV

This ring light has user-friendly controls and a hassle-free setup, and it claims to have high color accuracy. It also has a built-in diffuser which produces soft, beautiful lighting that fills in shadows on your subject's face with iconic catchlights in the eyes.

With that in mind, the Logitech Litra Glow is more a tool for lighting your work video calls or Twitch streaming sessions than it is a full-fledged do-everything option — but within its ideal use-cases, it excels. Setup is super-simple and integration with Logitech's G Hub gives you full control over its functions. Better still, if you have a Logitech keyboard or mouse you can use them to turn it on and off, or change settings. It does a great job of lighting calls and never once gave us a headache in our testing, while its $60 price puts it squarely in the middle of the best ring lights.

This 18-inch Neewer ring light has a fixed color temperature of 5500K, which matches a daylight-balanced light source. However, it also includes two color filters (white and orange), made from high-light-transmission plastic, which allow you to easily switch temperature from 5500K to 3200K. There's also a stepless dimming knob, which lets you adjust the brightness.

Many LCD models, from cheap TN-displays to color proofing S-IPS or S-PVA panels, have wide gamut CCFLs representing more than 95% of the NTSC color specification.

You get lots of options with this model: it can be used with a phone or nearly any type of stand-alone camera, since the kit comes with two cold-shoe mounts and a 1⁄4-inch-20 mounting option.

We think the Neewer RP18B Pro is the best ring light you can buy. It’s more affordable than the Wescott 18-inch ring light below, while also offering a wider adjustment range of 2700-7000K, Bluetooth connectivity for lighting adjustment and FX options via the Neewer app, plus a sturdy metal stand which features a heavy duty metal locking cuff mechanism. There’s also a mobile phone holder included so you can place your phone in the centre of the ring light. It also comes with a ¼” thread ball joint adapter instead of the mobile phone holder so you can use this ring light with one of the best cameras for vlogging. The RP18B Pro also comes with a carrying case that features a near light stand compartment so you can keep everything organized on the move.

Depth of field (DoF) is the distance between the nearest and furthest elements in a scene that appear to be "acceptably sharp" in an image. Why should I care?

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The evolution of energy standards and the increasing public expectations regarding power consumption have made it necessary for backlight systems to manage their power. As for other consumer electronics products (e.g., fridges or light bulbs), energy consumption categories are enforced for television sets.[35] Standards for power ratings for TV sets have been introduced, e.g., in the USA, EU, and Australia[36] as well as in China.[37] Moreover, a 2008 study[38] showed that among European countries, power consumption is one of the most important criteria for consumers when they choose a television, as important as the screen size.[39]

Although the RP19H is cheaper than the Neewer RP18B, it doesn’t feature Bluetooth connectivity or a wide temperature range like the more expensive model, so we think you should spend a little extra on the RP18B if you can. This ring light does feature decent build quality, however, and comes with a metal light stand (again this is not as sturdy as the stand that comes with the more expensive RP18B).

For several years (until about 2010), the preferred backlight for matrix-addressed large LCD panels such as in monitors and TVs was based on a cold-cathode fluorescent lamp (CCFL) by using two CCFLs at opposite edges of the LCD or by an array of CCFLs behind the LCD (see picture of an array with 18 CCFLs for a 40-inch LCD TV). Due to the disadvantages in comparison with LED illumination (higher voltage and power needed, thicker panel design, no high-speed switching, faster aging), LED backlighting is becoming more popular.[citation needed]

LED BacklightTV

It runs on the included AC power adapter or, when you’re far from a power outlet, on the two included NP-F750 lithium-ion batteries. While the Neewer RP18B Pro can run on batteries, that light doesn't come with them included, meaning the Wescott is the better of the two for portability straight out of the box. The included batteries provide up to 70 minutes at full power, according to the manufacturer. It’s also fully dimmable and equipped with an adjustable color temperature ranging from 3200K to 5600K — this is a much narrower range than the Neewer RP18B Pro.

But while we're slightly annoyed by the fact that it doesn't come with a stand, tripod (we used one of our own in the above photo) or mount, its quite-strong magnetic back makes it truly unique. No matter where you go, you'll be able to adjust it on the fly. It works with Elgato Stream Decks for your home setup, but it's also adjustable on the fly (brightness and warmth) via Android, iPhone, PC and Mac devices. Some of the below ring lights are rechargable, but the Key Light Mini is that plus so much more.

There are several challenges with LED backlights. Uniformity is hard to achieve, especially as the LEDs age, with each LED aging at a different rate. The use of three separate light sources for red, green, and blue means that the white point of the display can move as the LEDs age at different rates; white LEDs are affected by this phenomenon, with changes of several hundred kelvins of color temperature being recorded. White LEDs suffer from blue shifts at higher temperatures varying from 3141K to 3222K for 10 °C to 80 °C respectively.[19] Power efficiency may be a challenge; first generation implementations could potentially use more power than their CCFL counterparts, though it is possible for an LED display to be more power efficient.[citation needed] In 2010, current generation LED displays can have significant power consumption advantages. For example, the non-LED version of the 24" Benq G2420HDB consumer display has a 49W consumption compared to the 24W of the LED version of the same display (G2420HDBL).

Colored LED backlighting is most commonly used in small, inexpensive LCD panels. White LED backlighting is becoming dominant. ELP backlighting is often used for larger displays or when even backlighting is important; it can also be either colored or white. An ELP must be driven by relatively high[specify] voltage AC power, which is provided by an inverter circuit. CCFL backlights are used on larger displays such as computer monitors, and are typically white in color; these also require the use of an inverter and diffuser. Incandescent backlighting was used by early LCD panels to achieve high brightness,[8][9] but the limited life and excess heat produced by incandescent bulbs were severe limitations. The heat generated by incandescent bulbs typically requires the bulbs to be mounted away from the display to prevent damage.

A Borescope is an optical instrument that is used to visually inspect areas that are difficult to access. Borescopes from the leading manufacturers are ...

An ELP gives off uniform light over its entire surface, but other backlights frequently employ a diffuser to provide even lighting from an uneven source.

The Logitech Litra Glow is small and requires less desk space than some of the larger options in our list, but on the flip side it's not something you can mount a camera or phone into the middle of for easy streaming on the go.

These simple, donut-shaped devices generally use LED lighting to produce a diffused, continuous glow which makes you look your best on screen; unflattering shadows will be a thing of the past once you're using one.

Our favorite ring light overall is Neewer's 18-inch RP18B Pro, thanks to its great build quality and the included accessories in the box. It also features Bluetooth smartphone control, industry battery compatibility and a wide bi-color temperature range. However, if you’re on a tighter budget or simply need something different, you'll find something to suit among our picks of the best ring lights. All you have to do now is read on.

Why not check out our other photography picks:It's important that your other kit matches up to your competent new ring light. Make sure you read our guide to the best cameras if you're thinking about upgrading kit. Already know which side you're taking in the mirrorless vs DSLR debate? You'll want to read our picks of the best DSLR cameras or best mirrorless cameras. On a tight budget? Make sure to read our picks of the best cheap cameras. You need to be a dab hand in the edit suite these days for your photos to stand out online, so make sure you read our guides to the best photo editing software and best photo editing apps. The same goes for video too, so consider finding out what we think is the best video editing software, best free video editing software and best video editing apps. Finally, all those photos and videos are going to need to go somewhere, so make sure you know all about the best photo storage sites if your drives are already nearing full.

LED backlight are often dynamically controlled using the video information[22] (dynamic backlight control or dynamic "local dimming" LED backlight, also marketed as HDR, high dynamic range television, invented by Philips researchers Douglas Stanton, Martinus Stroomer and Adrianus de Vaan[23][24][25]).

The Wescott 18-inch ring light does have one advantage in that it comes with NP750 batteries to run away from mains sockets. And while the RP18B Pro is cheaper than the Wescott, buying Neewer’s battery plate plus two NP750 or compatible batteries will take your total spend higher. That said, most people will be using a ring light in a home studio set up where mains power is reachable, so we don’t think this is a deal breaker, especially as the RP18B Pro offers better features all round. One slight gripe we had is that the screw handles for securing the ring light to its frame are made out of cheap feeling plastic, although the rest of the light and the tripod all feel very sturdy.

Like Westcott and Nanlite, Godox has a good reputation for making quality lighting products. The LR150 is no exception, which is why it makes our list of the best ring lights.

Simple types of LCDs such as those used in pocket calculators are built without an internal light source, requiring external light sources to convey the display image to the user. Most LCD screens, however, are built with an internal light source. Such screens consist of several layers. The backlight is usually the first layer from the back. Light valves then vary the amount of light reaching the eye, by blocking its passage in some way. Most use a fixed polarizing filter and a switching one, to block the undesired light.

If you do want a ring light, with so many available at so many different price points, how do you choose which model is right for you?

Most LED backlights for LCDs are edge-lit, i.e. several LEDs are placed at the edges of a lightguide (Light guide plate, LGP), which distributes the light behind the LC panel. Advantages of this technique are the very thin flat-panel construction and low cost. A more expensive version is called full-array or direct LED and consists of many LEDs placed behind the LC panel (an array of LEDs), such that large panels can be evenly illuminated. This arrangement allows for local dimming to obtain darker black pixels depending on the image displayed.

Dec 1, 2017 — BERLIN - 1 December 2017: An explosive device found in the German city of Potsdam near Berlin has been defused, local police said on Twitter ...

The ring light itself is decent, rather than class-leading: color temperature is fixed unless you use filters and there's no way to adjust the brightness. But if you're looking for something small, portable and well priced, this could be the right ring light for your phone.

The LCD backlight systems are made highly efficient by applying optical films such as prismatic structure to gain the light into the desired viewer directions and reflective polarizing films that recycle the polarized light that was formerly absorbed by the first polarizer of the LCD (invented by Philips researchers Adrianus de Vaan and Paulus Schaareman),[29] generally achieved using so called DBEF films manufactured and supplied by 3M.[30] These polarizers consist of a large stack of uniaxial oriented birefringent films that reflect the former absorbed polarization mode of the light.[31] Such reflective polarizers using uniaxial oriented polymerized liquid crystals (birefringent polymers or birefringent glue) are invented in 1989 by Philips researchers Dirk Broer, Adrianus de Vaan and Joerg Brambring.[32] The combination of such reflective polarizers, and LED dynamic backlight control[23] make today's LCD televisions far more efficient than the CRT-based sets, leading to a worldwide energy saving of 600 TWh (2017), equal to 10% of the electricity consumption of all households worldwide or equal to 2 times the energy production of all solar cells in the world.[33][34]

On the light itself, there are two knob controls to adjust the color temperature (3000K to 6000K) and brightness of the light. It comes with a power supply, but no batteries, which makes this more suited for studio or home scenarios. It also comes with a built-in USB port to keep your smartphone charged. A nice extra on this ring light is that it lets you rotate the light head 180 degrees horizontally. The included tripod stand, meanwhile, can extend up to 78 inches.

Many types of displays other than LCD generate their own light and do not require a backlight, for example, OLED displays, cathode ray tube (CRT), and plasma (PDP) displays.

LED backlightmonitor

Ring lights are perfect for vlogging, especially if you're producing beauty content, as they light your face evenly and also give you that telltale ring reflection in your eye. However, they also have downsides: they can be expensive, while they're also relatively inflexible as they're designed primarily for lighting faces. If you want to do more types of content, a ring light alternative might be best for you.

Terry Sullivan is an experienced technology journalist who has covered consumer electronics including cameras, smartphones, audio tech and software among many other things. His work has appeared in the likes of Consumer Reports, PCMag, Lifehacker, and the New York Times and he is also a teacher, photographer, artist, and musician.

The article is an overview of interior, road and exterior architectural object lighting design strategies.

A method to further improve the color gamut of LED-backlit LCD panels is based on blue LEDs (such as gallium nitride (GaN) LEDs) that illuminate a layer of nanocrystal phosphors, called quantum dots (QDs).[13] The quantum dots convert the blue wavelengths to the desired longer wavelengths as narrow-bandwidth green and red colors for optimal illumination of the LCD from behind. The manufacturer, Nanosys, claims that the color output of the dots can be tuned precisely by controlling the size of the nanocrystals. Other companies pursuing this method are Nanoco Group PLC (UK), QD Vision, 3M a licensee of Nanosys and Avantama of Switzerland.[14][15] Sony has adapted quantum dot technology from the US company QD Vision[16] to introduce LCD TVs with an improved edge-lit LED backlight marketed under the term Triluminos in 2013. With a blue LED and optimized nanocrystals for green and red colors in front of it, the resulting combined white light allows for an equivalent or better color gamut than that emitted by a more expensive set of three RGB LEDs. At the Consumer Electronics Show 2015, a number of companies showed QD-enhanced LED-backlighting of LCD TVs, including Samsung Electronics, LG Electronics, and the Chinese TCL Corporation.[17][18]

Use casesThink about how you want to use the ring light. Are you just capturing casual photos on your phone? Then, you won’t need to spend a lot of money. But what if you are producing a weekly video podcast or episode for your YouTube channel? Then, you’ll want to pay more for a ring light that gives you more options.

The RP19H is the ring light to get if you need to shoot on more than one device simultaneously, as it has three cold shoe mounts. This means you can mount three smartphones or cameras for shots at different angles. This feels like a bit of a gimmick, as the space between the mounts is small, meaning the angles won’t be hugely different. Using three smartphones or cameras might be useful if there are a group of you in shot, though, as you can all record the same content on your own devices. You could use the cold shoes to mount an extra accessory like a microphone, though.

Unlike plastic/metal kit lighting, the FX system is comprised of architectural grade components engineered to be specified and installed by professionals.