Remember how exciting it was when cell phones were first able to show us pictures in color? Remember when we called them cell phones instead of smartphones because all they could really do was make calls and send text messages? Oh, you don’t, huh. Well, back in early 2000s, phones were just starting to show their colors and it seemed like magic. They had something called LCD screens (just LCD, no super) and their resolution was about 640 x 200 pixels with a pixel density of about 150 ppi and a palette of just over 4000 colors. We thought it was phenomenal.
Fast forward to today. SLCD, AMOLED, Retina display. Not quite 15 years later, we’re looking at screens with 2,560 x 1,440 pixels at 576 ppi (for perspective, the human eye is thought only to be able to see about 460ppi) and color counts in the millions.
But with all the advancement has also come some complication, especially for the layman who doesn’t really know what most if that stuff we just said really means. Well, sit tight, layman. We’re about to lay it out.
When you’re talking about cell phone screens, there are a few main things you’re really concerned with—size, clarity, brightness, and color. Size is pretty straightforward. It’s generally measured in inches here in U.S., from one corner of the screen to the opposite corner of the screen. If you remember a2+b2=c2 from basic geometry, we’re talking about c here. The other aspects require a bit more explanation, for which purpose we have created the following handy dandy chart.
Specs related to your smartphone screen
|Term||What it refers to||What it means to you|
(Liquid Crystal Display)
|Screen technology||LCD screens have been around since the early 1970s, first in watches and calculators, then in TVs and smartphones as color was added. LCD screens are backlit, in contrast with LED and OLED displays, which leads to greyer blacks and somewhat higher power consumption. They tend to be less expensive and sometimes have sharper detail since they do not require the same kinds of pixel formations as LED and OLED screens.|
|Super LCD||Screen technology||Super LCD is a version of LCD technology in which an air gap between the outer glass and the display element has been eliminated, creating less glare and a “closer” feel.|
(In plane switching)
|Screen technology||This is an upgrade on LCD technology that provides more uniform color reproduction and greater viewing angles than traditional LCD screens.|
|Retina display||Resolution||Retina display, which has nothing whatsoever to do with your actual retina, is an LCD technology that miniaturizes pixels in order to cram in more pixels into each inch of a display. This allows for higher resolution and greater high-contrast crispness, making for better reading.|
(Organic Light-Emitting Diode)
|Screen technology||OLED screens use organic carbon-based compounds that emit colored light when stimulated by an electric current. They generally produce darker blacks and sharper contrast, since pixels actually turn off to create them, as well as more saturated colors, making videos and images appear clearer and more vibrant. Also, since organic diodes emit light immediately when current is applied, OLED displays can have faster response times. Because they do not require a backlight, they are also thought to be more energy efficient.|
|Screen technology||The important part of AMOLED, the Active-matrix, is actually a technology that is applied to most smartphone screens these days. It means that each pixel is attached to a transistor and a capacitor that actively maintain the pixel state while other pixels are being addressed, as opposed to older passive matrix technology in which each pixel must maintain its state, well, passively. The take-away is higher refresh rates and lower power consumption.|
|Super AMOLED||Screen technology||Super AMOLED screens are said to be 20% brighter, 80% less reflective, and use 20% less energy than regular AMOLED. Samsung claims that its Super AMOLED display also reproduces colors that match to more than 90% of the colors visible in nature, compared to 70% on LCD screens. They use a two- rather than three-subpixel configuration (see subpixel below).|
(from picture + element)
|Resolution||Every image on your display is made up of tens of thousands, sometimes hundreds of thousands, of pixels. Each pixel on a given screen is the same size as all the others and displays a tiny part of the whole picture. It is the smallest controllable element represented on the screen. The more pixels, the more pixels the more visual information can be displayed, resulting in greater clarity and more detail. Measurements like 1080p and 1440p refer to standards of this measurement, 1080p indicating a resolution of 1920×1080, or “Full HD”, and 1440p indicating 2,560 x 1,440 resolution, or “Quad HD”. Ultra HD, or 4K, is something like 3,840 x 2,160.|
|Subpixels||Color||In digital screens, pixels are made up of red, green, and blue subpixels. Most often, each pixel has a red, a green and a blue subpixel, but, as noted above, Samsung has recently created a screen that instead use pixels made up alternately of one red and one green or one blue and one green subpixel. The configuration of subpixels affects primarily the range and exactness of color a screen is able to produce.|
(Pixels Per Inch)
|Resolution||This tells you essentially the number of pixels you could count across one inch of your screen. If your resolution is 100 PPI (and we sincerely hope it is not), then one square inch of your screen is 100 pixels wide and 100 pixels high, or 10,000 total pixels. For a decent picture, you want at least 300 PPI, but higher end phones these days have upwards of 500.|
|Gamut||Color reproduction||The color gamut is what one might expect if one has ever used or heard the term “run the gamut”. It refers to the range of colors that can be represented. The gamut of a particular device is generally compared to the gamut of colors that can be seen by the eye or to those that can be reproduced by other devices (see Samsung’s claim above).|
|Candela (CD)||Brightness (technically, luminance)||This is the unit used to indicate the light power emitted by a source in a particular direction, weighted according to a standardized model of the sensitivity of the human eye to different wavelengths. In practical terms, it is a measure of perceived brightness, with 1 candela being equivalent to about the amount light emitted by a common wax candle.|
|Nit||Brightness (technically, luminance)||A nit is the slang and much-used term for the unit cd/m2, the measurement of light (candelas) on a surface area (1 m2). Nits vary depending on what is displayed on the screen, so usually manufacturers provide a “maximum nits” measurement, which is what the phone gives off when the screen is all white. LCD phones tend to be brighter by nits than OLED, measuring sometimes more than 500, but really anything more than 250-300 should give you a fine experience.|
|Viewing angle||This refers to the maximum angle at which the variation of brightness, contrast, and color remains acceptable. A one-sided, flat screen has a maximum possible (though practically impossible) viewing angle of 180°, measured from looking flat on from one side to flat on from the opposite side. The average smartphone has a viewing angle around 30°. A good viewing angle is particularly important if you tend to set your phone down on the desk or table rather than holding it in your hands.|
(Graphics Processing Unit)
|Rendering power||Though not actually a quality of the screen, a good GPU is what makes a good screen worth having. Without it, the phone will caught up trying to actually get images up on its fancy screen, causing lag and sometimes even crashes.|
|Resistive touchscreen||Input method||Resistive touchscreens sense direct pressure applied by the user. They can be activated by your finger, a basic stylus, or a carrot stick, whatever you want to use to apply that pressure. The touch layer of these screens is usually made up of two transparent electrical layers separated by a small gap; when the layers come into contact, the contact is registered and voila. The drawback of resistive touchscreens is that they do not have the multitouch capacity that allows things like pinch-to-zoom.|
|Capacitive touchscreen||Input method||Capacitive screens work by sensing the electrical properties of the human body rather than pressure. Consequently, you need a specially designed stylus (like the Galaxy Note’s S-pen) that can replicate these signals if you want to be able to write on them with anything but your finger. Capacitive touchscreens often seem more sensitive than resistive screens and tend to be more durable.|
|Multitouch capability||Input method||Multi-touch is the capability some touchscreens and touchpads have that enable them to recognize two or more points of contact at once. This is what allows your smartphone or touchscreen laptop to recognize gestures like pinch-to-zoom.|
WOndering about what’s under all this brightness and beauty? Check out the specs on your smartphone’s tiny (but powerful) brain.