I put the tilde on the p to v comparison because for glancing angles (where the light is travelling almost horizontal, large angle of incidence) it makes sense to talk about vertical polarized light but if the light is travelling more and more perpendicular to the surface (smaller angles of incidence) it makes less and less sense to talk about vertically polarized light.

Our recommendations for webcams are weighted pretty heavily toward the image each webcam produces, as you might expect. But there are a number of additional criteria we look at when making a webcam recommendation. A separate article provides a detailed explanation of how we test webcams at PCWorld, but here’s a summarization of the process:

Don’t worry about fixed-focus, as virtually all webcams have been pre-configured at a focal length that’s about the distance between your face and your laptop or monitor. You’ll need to account for this with tripods, however, or pay a little more for an autofocusing webcam. Autofocus webcams are handy for situations where you may be moving about the room, but beware distracting webcams that frequently refocus.

The autofocusing Logitech Brio 4K supports various resolutions and frame rates, including 4K Ultra HD at 30fps, 1080p at 30- or 60fps, and 720p (HD) at 30- or 60fps. According to our review, Logitech’s RightLight 3 technology snaps photos and video in a range of lighting conditions. It can adjust the field of view from between 90 degrees to 78 degrees or 65 degrees. You will need to download the Logitech app for fine-grained control options, however.

S-polarizedlight

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But yes, the IdeaCam S1 Pro also works as a generic everyday webcam, too. It also looks particularly nice under good lighting, so it’s better for a user who isn’t expecting the camera to do a lot of heavy lifting in that regard. And while it might not offer the absolute top-of-the-line options, it never really fails at anything, either. It’s just a good, solid value. Period.

It’s also best for someone who will be streaming from an environment without a lot of (changing) natural light, but is still well-lit by a lamp or screen.

With so many webcams on the market, manufacturers are trying hard to differentiate their products. The new trend is a small tripod, which gives you more options for mounting the camera. Not all webcams include this. Normally, however, you can simply clip the webcam to the top of a display or a laptop with its “jaws” clamp, so a tripod isn’t really necessary unless you move around a lot or want a different angle.

Elliptically polarizedlight

The IdeaCam S1 Pro would probably be our favorite webcam if it wasn’t for the $100 or so price premium it commands, which isn’t for everyone. It’s robustly built, and ships with a free software utility that adds to its capabilities. (Zooming in and out is most easily accomplished via the remote control, which does take up more room on your desk.)

This webcam is also going to work better on a desktop monitor, by lieu of its rather simple mount. It feels flimsier when attached to a laptop.

This is for the person who says, “I want to upgrade my webcam, but I want to spend the least amount of money possible.” You’ll still get a decent upgrade; more than you would expect, actually. If a $10 discount matters, buy the cheaper 1080p version.

What is plane polarizedlightin Chemistry

Soon, yes! Microsoft is testing a smartphone webcam feature in Windows 11 that sounds like it should be out in a month or two. The feature would allow you to mount a smartphone (how you do it is up to you) and then use either its front or rear camera as a webcam in any and all video applications. You’ll need a phone running Android 9 or above, and the connecting software to enable it to talk to Windows.

However, imagine a beam travelling directly upwards from the ground in the $\hat{z}$ direction. In this case the polarization lies in the $\hat{x}$, $\hat{y}$ plane. It doesn't make sense to me to call either of these vertical polarization. Rather, we would be better served calling them "East-West" and "North-South" polarized, for example. The key point here is the geometric and coordinate dependent nature of how we call polarizations.

s and p are defined with respect to the plane of incidence as described in the Wikipedia article. The plane of incidence is defined by two vectors. One vector is the normal vector to the surface (the vector which points out of the surface). The other vector is the direction of propagation for the light under consideration. Often these two vectors are not parallel and thus they describe a plane*. This plane is called the plane of incidence.

The webcam slides in and out of a robust mount quite easily. Pair that with the macro lens, and you can zoom in on detail work for presentations or hobbyists. The webcam has autofocus, though you’ll probably want to lock down the focus for the macro lens. It all works surprisingly well together, though.

If you want to look your very best on cam, buy this webcam. The lack of 4K60 captures may rule out high-end game streaming, but the ability for the camera to capture your face under most lighting conditions means a lot of other people will love it. Whether you’re pitching products on a Zoom or Teams call or you want to stand out among style-conscious peers, the Razer Kiyo Pro Ultra is the webcam for making a strong impression.

You’re going to find that it cheats in the frame rate a bit, and I wasn’t wild with how well it captured my image, from a color perspective. But for about $50, for a 4K camera? It’s worth investigating.

It’s important to note that of the three major videoconferencing services (Microsoft Teams, Zoom, and Google Meet) only Teams will automatically scale up your video to 1080p if your network and your webcam support it. You can enable 1080p video in Zoom and (finally!) in Google Meet, but they require some manual adjustment in the app’s Settings menu. All three services will eventually auto-scale video calls for 1080p cameras — it’s just a matter of time.

All of this combines to produce an image that looks simply outstanding. It would be nice to see this camera produce 60Hz at 4K; instead, you have to choose one option or the other. But check out the sample screens in our review, and you’ll agree that it all looks as though a professional captured it. It even handles odd lighting situations very well. Colors just pop! We’ve highlighted some of the shortcomings above, but they’re overshadowed by everything else this webcam does.

Why wouldn’t you buy a webcam that can protect your PC via biometrics, log you in with your face, and make you look great on a video call? The Logitech Brio 4K Ultra HD webcam is one of the small group of Windows Hello webcams that can perform both tasks.

Linear polarization

I also love the fantastic software package that accompanies the webcam, which on the Tiny 1 was the best I’ve ever seen. I’m less impressed by two new features: voice commands, which are useful but not necessary, and new “beauty” features that use AI to adjust your face. While the latter features work, I prefer a more natural appearance, flaws and all.

You may have used Windows Hello with a fingerprint reader or another laptop. The camera simply “recognizes” you, logging you in. It’s exceptionally convenient. We have a separate article on the best Windows Hello webcams.

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*However for the case of light which is shining directly incident onto a material surface the two vectors are parallel and no plane is defined. I'll discuss this case shortly.

If the electric field is directly incident on the surface the propagation direction and surface normal are parallel so we cannot define a plane of incidence. In this case all polarizations "lie flat" in the plane of the material surface so it is sort of like all polarizations are "s-polarized". This is comparable to the case when light was travelling directly upwards against gravity and all polarizations looked like horizontal polarizations so it didn't make sense to talk about horizontal and vertically polarized light anymore. In this case we must introduce a new different reference frame if we want to talk about the polarization of the light field.

Yes and no. These webcams all connect to your computer directly, via a USB port, and you can record video from them while offline. Your computer will then need to be connected to either ethernet or to Wi-Fi for you to be able to chat with a friend or business partner, however.

I also load any utility software available and explore what options those provides. Does the webcam provide any additional functions, such as a top-down perspective? Ring lights? I try those out, too.

This camera would work equally well with a small conference room or even a family gathering, such as a living room where one family talks to grandparents overseas. It’s still a fixed-focus camera though— if you want an autofocusing model I recommend you pay about $100 for the upgraded NexiGo N680p instead.

Anyone who doesn’t like entering a password or PIN but doesn’t want to skimp on webcast quality, either. Seriously, as biometric identification becomes more prevalent, with passkeys standing in for passwords, Windows Hello will become more important. Put that way, the Brio 4K is cheap at the price.

The best webcam makes you look your best — for less. Most laptops ship with a 720p webcam, so a 1080p webcam or even a 4K webcam can make you stand out by comparison.

If the budget webcams we selected above were ideal for students, this is the lecturer’s webcam. Share your slides with your student (or your clients, in a business setting) and let your video app project a snapshot of your face over them as you illustrate your point. If you walk and talk, this is the webcam for you.

H and V polarization usually refer to some arbitrary reference frame. This reference frame is usually defined by the direction of gravity (call this $\hat{z}$ direction). If light is travelling "horizontally" (meaning perpendicular to the direction of gravity, for example in the $\hat{y}$ direction) then we can talk about horizontally and vertically polarized light. For vertically polarized light the electric field is parallel to the direction of gravity so it is in the $\hat{z}$ direction. For horizontally polarized light the electric field is perpendicular to the direction of gravity, that is in the $\hat{x}$ direction. Note that in both cases the electric field is perpendicular to the direction of light propagation.

If you have more than one person on camera at any one time, consider something like the NexiGo N980P. During the pandemic, the local middle school’s drama department broadcast monologues and scenes via Zoom, which allowed students the opportunity to perform. But a narrow webcam wouldn’t have allowed these scenes to be broadcast as effectively.

Note regarding glare and sunglasses and the Brewster angle: You have pointed out that unpolarized light incidence at (or near) the brewster angle will be filtered and (mostly) s-polarized upon reflection. If the surface under consideration is horizontal (asphalt on the road, or standing water, for example) then we know that s-polarized light is h-polarized light. Thus if we want to filter this out using sunglasses for example we should make the sunglasses eliminate h-polarized light. Polarizing sunglasses are designed to eliminate h-polarized light when the wearer is standing upright and holding their head in the usual way. If they tilt their head, however, then their sunglasses will now let in more h-polarized light and allow in more v-polarized light. The angle of the sunglasses defines a new coordinate system. Note also that if the surface is vertically oriented (such as the rear window of the car in front of you) then since sunlight is typically coming from above, the s-polarized reflected light will again be mostly horizontally polarized. This means that generally polarizing sunglasses are good and reducing glare from all sorts of objects assuming the sunlight is coming from above. However, during sunrise and sunset the sun is lower in the sky so the reflected s-polarized light may now have large components in the vertical direction so the sunglasses will not work as effectively.

As the lead reviewer, I take sample images both in my downstairs office, which is normally lit by a combination of dim artificial light and indirect natural lighting. I use a second shot in brighter light, with a nice colorful background that mimics a real-world environment. I’m not really looking for the best-case scenario, as most webcams now take good shots in clear, natural lighting. But how do they do when lighting conditions aren’t ideal? I think that’s important.

Finally to unite all of these concepts. We see that horizontal and vertical polarization refer to the direction of polarization compared to the direction of gravity and s and p-polarization refer to the direction of polarization compared to the plane of incidence. If the surface normal is pointing either in the direction of gravity (as implied by the figure in the OP) or perpendicular to the direction of gravity (a surface which is vertical like a mirror in the restroom) then there is a relationship between s and p-polarized and horizontal and vertically (h and v) polarized light.

What sold us on this webcam are the basics: It’s just a good webcam for an affordable price. As such, it will appeal to a broad segment of buyers: work-from-home employees, small businesses, and general consumers. If you’re tired of your laptop’s 720p webcam and want even more, start here with the Anker PowerConf C200.

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BenQ’s marvelous webcam offers a substantial amount of value, from its midrange price to the multiple, useful accessories that ship right inside the box. What I think I like most about this webcam, though, is that it excels as a webcam, then adds additional value through its peripherals, including both a macro (closeup) lens as well as a free remote control. This almost-but-not-quite 4K webcam even flips over for a top-down view.

Anti-reflection coatings on solar cells are similar to those used on other optical equipment such as camera lenses. They consist of a thin layer of dielectric ...

For USB webcams, it will be as simple as plugging the camera into your computer’s USB port, and then connecting to the internet via your computer.

From there, we remove the webcam, examine the packaging, and see how well it sits atop some of our monitors and laptops. Does it grip tightly, or tend to wobble? Is the cord long enough, and does it use USB-A or USB-C?

Polarization oflightnotes PDF

While the Tiny 2 webcam boasts the same gimbal and tracking features as the first Tiny PTZ webcam, OBSBOT used a bigger 1/1.5-inch 50Mpixel sensor in the new model that lets in more light and provides a slightly clearer picture. So it accomplishes what you’d expect in a webcam: It wildly succeeds as just a webcam, with gorgeous 4K HDR images — but provides the increased tracking capabilities to add value. It almost tracks a little too well; avoid zooming in too close if you walk around so as not to give your viewers vertigo!

The question you should always ask of budget hardware is, what corners did they cut? Here, the answer is: not many. This is a 4K webcam at a cheaper price than many 1080p webcams, and that alone makes it noteworthy. Okay, it has manually adjustable focus, but that’s not a problem if you don’t move around a lot. Similarly, backlight adjustment is typically handled automatically, but this webcam’s manual adjustment is not a problem you work in a single location you can dial it in and forget it. There’s a flip-over privacy shutter, and a button to mute the mic.

Otherwise, this is a good 1080p/30fps fixed-focus webcam, whose other signature feature is an iris-like physical webcam shutter. Once the webcam is in use, the iris opens; if turned off or disconnected, the shutter closes. The images this webcam produces are good, and the noise-cancelling mics are too.

Circularly polarizedlight

Technically, most webcams are plug and play, so you should simply be able to connect them to your PC to get them to work. Many, however, require their own software utilities to be installed to take advantage of specific features and to facilitate automatic updates. To actually use your webcam in a conference call, however, you’ll need to use Zoom, Microsoft Teams, Google Meet, or another videoconferencing app. Make sure you enter the app’s settings menu and select the webcam’s camera and microphone to provide the audio and video for your call.

There’s a potential wild card that may be attached to webcams in the future: artificial intelligence, specifically Windows Studio Effects. Right now, the current Surface Pro 9 (5G) uses the AI capabilities in the Qualcomm Snapdragon processor to apply background blue, automatic panning effects, and more. (Our review discusses this.) Other laptops that use Intel Core and AMD Ryzen processors don’t include AI capabilities — yet. Specific models in the 13th-gen mobile Core and AMD Ryzen 7000 Mobile series include some basic AI capabilities, and future processors in both families may offer AI capabilities and therefore Windows Studio Effects.

If 4K matters, and you don’t feel like spending a lot, this is the camera for you. To me, this feels like a good choice for a student, or someone who wants to look good in front of their friends and maybe while taking remote classes, but just doesn’t want to spend a ton of money.

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Our first criteria is price. We don’t want you spend more than you have to. But it’s fair to say that a more expensive webcam might be worth it if it offers more. So we factor in features: the resolution, the refresh rate, whether the camera pans or zooms, or offers something rather novel, such as the ability to show a different perspective.

Additional features include an adjustable field of zoom that crops down to 65 degrees, meaning you can orient the camera on your face alone. The camera autofocuses, too. Naturally, there are noise-canceling mics and a privacy shutter that actually turns off the entire device. You will need Anker’s free Windows software, though, to enable some of these features. (That’s available on the Anker website.) We weren’t sold on the need for original software at first, but many other webcams now offer similar apps to enable full functionality.

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Why you should trust me: PCWorld has been testing PC hardware since the 1980s, and I’ve been a technology journalist for 30 years, with extensive experience in reviewing PC hardware. When it comes to webcams, my recommendations are based on hands-on testing in real-world scenarios. I also tap the expertise and published reviews of my counterparts in Sweden and Germany to offer a comprehensive view of the current webcam landscape.

Looking like you’re on television will subtly lend you authority. People gravitate toward celebrities, and a 4K, 60Hz webcam is basically what your TV offers. If you’re an executive or making sales calls over Zoom or Teams, a premium webcam may give you an edge. That’s why professional streamers use them, after all.

Mark has written for PCWorld for the last decade, with 30 years of experience covering technology. He has authored over 3,500 articles for PCWorld alone, covering PC microprocessors, peripherals, and Microsoft Windows, among other topics. Mark has written for publications including PC Magazine, Byte, eWEEK, Popular Science and Electronic Buyers' News, where he shared a Jesse H. Neal Award for breaking news. He recently handed over a collection of several dozen Thunderbolt docks and USB-C hubs because his office simply has no more room.

This fixed-focus 1080p webcam captures frames at a smooth 60 frames per second, as opposed to the more standard 30fps. You’ll look smoother and more lifelike as a result. The wide angle means that it will work well in a conference room. A privacy shutter is included.

for autocollimators with f≤300 mm. The reticle ad- justment amount ±10 µm. An autocollimator with geometrical beam splitter is arranged similarly (see ...

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Budget buyers and mainstream users looking to improve upon their laptop’s 720p webcam, and who also want the added security of Windows Hello biometric security. Until recently, Windows Hello capability would probably have put this webcam over $100. (If you want Windows Hello with even more advanced features, see our pick below for best premium Windows Hello camera.)

Not everyone needs a wide-angle webcam. But this does allow you to show off more of a scene than an ordinary webcam does, which makes it a valuable tool for specialized applications.

If that's the case then sunlight (unpolarized light) will be reflected as horizontally polarized so to reduce glare effects the polarizing sunglasses must block the horizontal direction of polarization, right?

Once you set up the HelloCam, you’ll just need to present your face to the camera, and poof! You’re logged in. With biometric identification becoming more and more important to PC security, this is a worthwhile investment.

A standard webcam captures video at 30 frames per second, and will look “normal.” You’ll notice the smoothness of a 60fps camera though, and so will people you’re on a video call with.

My previous pick, the Monoprice 2K USB Webcam, always felt a little deficient: not bad, but not great either. I wasn’t especially happy with the quality. eMeet’s camera feels like a step up. It’s not perfect. However, the 1440p resolution is a better both on paper and in the real world. The other part of the equation that often gets passed over are how well the noise-cancelling mics work, and in this case I was pretty impressed.

My doubt comes from a discussion we had in class about the Brewster angle, glare effect produced by the reflection of sunlight on water and polarizing sunglasses.

The camera’s field of view can vary. A 90-degree FOV helps people focus on you (and perhaps not the mess you’ve hidden off to the side). A 110-degree or higher FOV works better for group shots, although distortion can become a problem the wider your FOV gets. A 65-degree FOV may be perfect if it’s just you.

Some webcams can work without a computer, but not all of them. USB webcams, featured here, connect via USB to a computer and require it to operate. USB webcams are most often those used for video chat or live streaming from your computer on websites such as Twitch.

So an unpolarized electromagnetic wave as light when incident on an interface air-water will be reflected as an "s" polarized light at the Brewster angle. This means it oscillates on a plane perpendicular to the plane of incidence, hence parallel to the surface? If yes, then can we say that an s-polarized light is equivalently said to be horizontally polarized?

I haven’t tested every one of these webcams, just most of them — and I describe how I test under my recommendations. You can also refer to my separate story on the best Windows Hello webcams for recommendations that aid videoconferencing and log you into your PC. Two recommendations from that list — a premium and budget option — appear on this list.

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Linearly polarizedlight

This camera is also available from multiple retailers, which helps keep the price down — a must for a budget webcam. To be fair, you’ll notice the review compares the C960 2K to its predecessor, the more vanilla (1080p) C960. It’s about $10 cheaper. The C960 2K’s picture is marginally better, with improved autofocusing, but I think that the C960 2K’s mics are genuinely superior.

\begin{align} p\text{-polarized} & = \text{vertically polarized}\\ s\text{-polarized} & = \text{horizontally polarized} \end{align}

A standalone 1080p webcam can greatly improve how you look on your next Zoom call. Here’s what to look for: Prioritize a 1080p webcam, then a higher refresh rate, then jump up to 4K. If you can get more than one feature, great! Unless you’ll be moving about a lot, a fixed-focus webcam will do just fine.

Polarized and unpolarizedlight

The Razer Kiyo Pro Ultra claims to offer DSLR-quality images, and boy, it comes pretty close! This webcam captures video with a massive 2-inch lens at 4K at 30Hz or 1080p at 60Hz, using autofocusing technology that does a great job. The camera also can zoom in to offer a field of view between 72 degrees and 82 degrees, making sure that you, and you alone, are on cam.

p-polarized light is light where the electric field vector lies in this plane of incidence. s-polarized light is light where the electric field vector is perpendicular to this plane of incidence. If you think about this in terms of the material surface you can see that the electric field vector either pokes in or out of the material surface for p-polarized light while it "lies flat" in the plane of the material surface.

Think of a 90-degree FOV as one that would show two people seated side-by-side at what you would consider a “standard” distance from a webcam, or a foot or two. A 110-degree FOV can show three people, squeezed a bit close together. Keep in mind that many videoconferencing applications offer the option of virtual backgrounds, which eliminate visual clutter.

These devices are not a privacy threat, for the simple reason that they can be unplugged easily. Most have a flip-down privacy shutter, but you could always put tape over the camera or drape it with a dark cloth.

This definition of horizontal and vertical polarization also makes sense for light travelling at some reasonable angular deviations from the horizontal plane. We can talk about polarizations which mostly don't have components in the $\hat{z}$ direction, horizontal polarizations, and polarizations which mostly do have components in the $\hat{z}$, vertical polarizations.

This 4K webcam does something unique: It follows you. Floating on a gimbal, this tiny(!) webcam can literally pan, zoom, and rotate essentially 360 degrees, using AI to lock on your face and follow it as you walk around a room.

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s and p polarizations are different from horizontal and vertical polarizations. As described above, horizontal and vertical usually refer to the direction of the electric field with respect to gravity. s and p polarizations are instead defined with respect to a reference frame which is related to the surface with which the light is interacting. The surface can be oriented in an arbitrary direction with respect to gravity so we see that s and p are unrelated to horizontal and vertical polarization.

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Finally, if the webcam provides any noise-cancelling mics (and most do) I play some background music on my phone and make a recording on my laptop using Windows Sound Recorder. A good noise-canceling mic will try and minimize these distractions.

An aberration is a deviation of a ray from the behavior predicted by the simplified rules of geometric optics.

Yes, integrated ring lights are now a thing on premium webcams, and worth the money if lighting is a challenge for you. While the integrated light will certainly help with lighting, a big bright monitor display (use a full-screen version of Notepad for a white screen) in front of you can serve a similar function. You can also purchase a ring light separately.

If you’re a streamer (a woodworker or baker, say) then the ability to flip the webcam into a top-down mode, then undock the IdeaCam S1 Pro and the bring it in close with the macro lens, feels like a tool no other webcam offers.

The Anker PowerConf C200 offers an affordable yet substantial upgrade from the 720p cameras found in most laptop webcams to a 1440p webcam, yet does so at an affordable price. The webcam also works well in low light, a pitfall of many webcams. For all that, at just $60? That’s a solid value in my book, and makes this webcam our top recommendation.

My preferred webcams offer at least 1080p resolution at a ballpark price of between $50 to $70. This webcam goes a step further by offering Windows Hello. This biometric login technology is found on most modern laptops, but not on older ones. If your laptop lacks this technology, the HelloCam is an excellent way to add it — and for very little out of your wallet.

IP webcams however, can connect directly to a network, router, or modem and do not require a computer at all in order to work. IP webcams are most often used as security cameras or for live feeds that upload directly to the cloud. Those are separate products, however, and not the same webcams we’re talking about here.