Seiko Epson Corporation

Resolution

A criterion indicating fineness and smoothness when displaying, printing, and loading the data with a scanner. It is determined by signals and pixels. For display equipment, it is the number of dots displayed on the screen. As the value becomes larger, text and images are displayed clearly with little aliasing.
Currently, XGA for data projectors and 720P for home projectors are primarily used, although it depends on the price range.

Contrast

Adequate contrast for ordinary use can be achieved

When used in a normal indoor environment (from 20lx when lights are out to 300lx when fluorescent lights are on) you can obtain adequate contrast, which is one of the features of HTPS.

Light output (Brightness)

Light output is a term indicating the brightness when the display status of the whole screen is white. There are several units of brightness such as lumen, candela (cd), and lux (lx). Lumen is generally used for the projector. Lumen is a unit indicating the projector light output unified by ANSI(American National Standards Institute). Using an ｌumen value, you can compare the brightness exactly because this value does not change according to the projection size.
It is calculated by the following formula: light output (lumen) = illumination (lx) × screen area (m2). For example, eye-friendly illumination is said to be about 500lx, and you need 1500 lumen to project the image on a 100 inch (about 3 m2) screen. Currently the normal illumination is 1000 - 1300 lumen for mobile models, 1500 - 2500 lumen for mid-range models, and more than 3000 lumen for high-end models.