Understanding Monitor Measurements: Physical Size Explained

The physical size of a monitor is typically measured in inches, from one corner of the screen to the diagonally opposite corner. This method of measuring screen size was inherited from the first generation of CRT televisions, which had circular picture tubes. As a result, the external diameter of the bulb was used to describe their size. Today, this measurement provides an indication of the display area available for viewing content on the screen. It's important to note that the diagonal length is different from the screen resolution, which is measured in pixels. When measuring the size of a monitor, only the screen itself should be measured, excluding the bezel or frame.

Diagonal measurement

The size of a monitor is usually described by the length of its diagonal, which is the distance between opposite corners, typically measured in inches. This method of measuring screen size was inherited from the first generation of CRT televisions, which had circular picture tubes. Since these tubes displayed rectangular images, the diagonal measurement of the visible rectangle was smaller than the diameter of the tube due to the thickness of the glass surrounding the phosphor screen.

The diagonal measurement is typically what is referred to when describing the size of the monitor. To find the diagonal measurement, use a tape measure or ruler to measure the distance between opposite corners of the screen, for example, the top left corner to the bottom right corner. Do not include the bezel or frame that borders the screen in your measurement.

For monitors that are too large to measure diagonally, or if you don't want to risk smudging the screen, you can use the Pythagorean theorem to find the diagonal distance. Measure the width and height of the monitor, square these numbers, add them together, and then find the square root of the sum. This will give you the diagonal measurement.

It is important to note that the diagonal length should not be mistaken for the screen's width or height, as these are separate measurements. If you have limited desk space, for example, you should pay close attention to these dimensions as well, as you cannot deduce the width or height from the diagonal length alone.

Aspect ratio

The aspect ratio of a monitor is the proportional relationship between the physical width and height of the display. It is expressed as two numbers separated by a colon (x:y), where x corresponds to the width and y to the height. For example, a 16:9 monitor will have 16 pixels on the horizontal axis for every 9 pixels on the vertical axis.

The aspect ratio is calculated by measuring the width and height of the screen in pixels or inches and then dividing the width by the height. For instance, a resolution of 1920 x 1080 pixels would result in an aspect ratio of 16:9 (1920 divided by 1080 equals 1.78).

Common aspect ratios for monitors include:

• 4:3 - This aspect ratio was standard for many CRT monitors and early LCD monitors but has since been largely replaced by widescreen formats.
• 16:10 - This aspect ratio is commonly used in corporate spaces and was previously the most common for widescreen computer monitors.
• 16:9 - This is the current standard aspect ratio for widescreen monitors and is used for HDTV and most video content.
• 2.35:1 - This is an ultra-widescreen aspect ratio commonly used in cinema for panoramic shots and is available in some monitors for gaming and professional applications.

When choosing a monitor, it is important to consider the aspect ratio in relation to its intended use. For example, the 16:9 aspect ratio is well-suited for modern HDTV broadcasts, while the 16:10 aspect ratio is better for viewing documents in A4 size or photographs in the standard 135 film format.

Physical dimensions

The physical dimensions of a monitor refer to its screen size, which is typically measured in inches diagonally from one corner to the opposite corner. This method of measuring screen size was inherited from the first generation of CRT televisions, which had circular picture tubes. As a result, the external diameter of the bulb was used to describe their size.

When measuring a monitor, you should only measure the viewing screen and exclude the frame, bezel, or border. The diagonal measurement is the most commonly used and referred-to method when describing the size of a monitor. This is usually listed in the product specifications and can be found on the box or online.

To physically measure the diagonal size of a monitor, you can use a standard tape measure or a ruler. Place the measuring tool at the bottom left or top left corner of the screen and extend it diagonally to the opposite corner. This will give you the diagonal size in inches.

It's important to note that the aspect ratio and resolution of a monitor are separate from its physical dimensions, but they do affect other factors such as the display surface area and sharpness. Common monitor sizes range from around 19 inches to over 40 inches diagonally, with popular sizes including 21.5 inches, 24 inches, 27 inches, and 32 inches.

Screen resolution

The screen resolution of a monitor is a measurement of how many pixels it contains, expressed as width x height. For example, a resolution of 1920 x 1080 means the screen displays 1920 pixels horizontally and 1080 pixels vertically, resulting in a total of 2,073,600 pixels on screen.

The higher the resolution, the more detailed the image can be, as a higher resolution means a higher pixel density and more pixels packed into every square inch of the screen. This results in smoother lines and sharper images. However, the benefits of a higher resolution become less noticeable over a certain threshold, known as the point of diminishing returns.

Different screen sizes can have the same resolution, so it's important to understand both the size and resolution of a screen when making a purchase. The resolution of a screen will also determine how much content can fit on the screen. A higher resolution screen will display more of what you're working on, reducing the need to scroll.

When comparing screens of the same size, the one with the higher resolution will display sharper images, but the elements on the screen, such as icons and text, will appear smaller.

The standard way of expressing resolution uses pixels, but an alternative way is to use "dots per inch" (DPI) or "pixels per inch" (PPI). PPI is the correct term for monitors and other displays, and refers to the number of pixels per unit distance or area.

Pythagorean theorem

The physical size of a monitor is typically described by the length of its diagonal—that is, the distance between opposite corners. This method of measurement was inherited from the first generation of CRT televisions, which had circular picture tubes.

The Pythagorean theorem is a fundamental principle in geometry used to calculate the diagonal of a rectangle based on its width and height. The theorem states that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides. In the context of monitor size, this can be expressed as:

Diagonal^2 = width^2 + height^2

Here's an example to illustrate this:

Let's say you have a space for a television screen, and the width and height of the area are 48 inches and 36 inches, respectively. To find the ideal diagonal screen size:

• Square the width: 48^2 = 2304
• Square the height: 36^2 = 1296
• Sum the squares: 2304 + 1296 = 3600
• Take the square root of the sum: sqrt(3600) = 60 inches

So, the ideal screen size for this space would be a 60-inch diagonal television.

The Pythagorean theorem is particularly useful when comparing screen sizes of devices with different aspect ratios. For example, a 5.8-inch phone with a traditional 16:9 aspect ratio will have a larger screen area than a 5.8-inch phone with an elongated 18.5:9 aspect ratio, even though they share the same diagonal measurement. By applying the Pythagorean theorem, you can calculate the actual screen dimensions and areas to make more informed comparisons.

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