On screen size vs screen size

Ignoring the technology actually used to create the display (CRT, LCD, plasma, projection, whatever), there are certain characteristics of computer displays that are commonly confused:

- physical screen size. Measured in millimeters x millimeters, or inches by inches, or approximated by a diagonal measurement (14", 16", 19"...) and an aspect ratio (4:3 if not otherwise stated, 16:9 or 16:10 if widescreen.

-logical screen size, often called "resolution", but it isn't. Pixel count in columns by rows: 640x480, 800x600, 1024x768, 1280x1024, 1280x768, 1600x1200, 1920x1080, 2048x1536...

- screen resolution. Measured in dots-per-inch or dots-per-cm. 65dpi, 72dpi, 90dpi, 120dpi, 144dpi... this is the result of dividing the logical screen size by the physical screen size.

When you ask someone what size screen they are using, you might get either of the first two responses. When you ask what resolution they are using, you might get any of the three.

How are they important? Well, physical screen size provides an angle of view. If you sit a little less than arm's length from a screen, a 12" screen is tiny, and a 20" screen is pretty nice. A 30" screen is almost overkill... almost. But given a particular physical size, higher resolution (or a larger logical screen size, same thing) is always better. Due to stupidities in the way windowing systems used to handle these things, people often have the notion that a higher resolution screen means everything gets smaller, and thus harder to see. But a modern windowing system renders text and scalable graphics in the same physical size regardless of the logical size, so things remain the same visible size, but more dots are used to draw them, and so they are easier to read -- text is smoother, graphics have more detail.

At home, I use two 17" monitors running at 1600x1200. This doesn't feel like enough visual space any more, although it is generally enough logical space. At work, I have a 19" monitor now running at 2048x1536 (Until Friday it was at 1600x1200, which felt a little loose). This is also not quite enough visual space -- and now it doesn't feel like enough logical space, either. What to do, what to do...

On screen size vs screen size

Ignoring the technology actually used to create the display (CRT, LCD, plasma, projection, whatever), there are certain characteristics of computer displays that are commonly confused:

- physical screen size. Measured in millimeters x millimeters, or inches by inches, or approximated by a diagonal measurement (14", 16", 19"...) and an aspect ratio (4:3 if not otherwise stated, 16:9 or 16:10 if widescreen.

-logical screen size, often called "resolution", but it isn't. Pixel count in columns by rows: 640x480, 800x600, 1024x768, 1280x1024, 1280x768, 1600x1200, 1920x1080, 2048x1536...

- screen resolution. Measured in dots-per-inch or dots-per-cm. 65dpi, 72dpi, 90dpi, 120dpi, 144dpi... this is the result of dividing the logical screen size by the physical screen size.

When you ask someone what size screen they are using, you might get either of the first two responses. When you ask what resolution they are using, you might get any of the three.

How are they important? Well, physical screen size provides an angle of view. If you sit a little less than arm's length from a screen, a 12" screen is tiny, and a 20" screen is pretty nice. A 30" screen is almost overkill... almost. But given a particular physical size, higher resolution (or a larger logical screen size, same thing) is always better. Due to stupidities in the way windowing systems used to handle these things, people often have the notion that a higher resolution screen means everything gets smaller, and thus harder to see. But a modern windowing system renders text and scalable graphics in the same physical size regardless of the logical size, so things remain the same visible size, but more dots are used to draw them, and so they are easier to read -- text is smoother, graphics have more detail.

At home, I use two 17" monitors running at 1600x1200. This doesn't feel like enough visual space any more, although it is generally enough logical space. At work, I have a 19" monitor now running at 2048x1536 (Until Friday it was at 1600x1200, which felt a little loose). This is also not quite enough visual space -- and now it doesn't feel like enough logical space, either. What to do, what to do...