Tips on how to choose a home theater projector--ANSI lumens & ISO lumens.

by Chelsea . on April 01, 2022

What is the difference between ANSI lumens and ISO lumens? The distinction can be made in three ways. 

Different Institutions

ANSI lumens are the method of measuring the luminous flux of a projector developed by the American National Standards Institute; while ISO lumens are the various standards set by the International Organization for Standardization for projectors. 

Different Measurement Methods

ANSI lumens are measured using a "nine-point" measurement method, which does not specify measurement standards and only takes nine points on the projected screen for calculation testing.

Different brightness standards

Since projectors were more widely used in Europe and the United States in the early days, most European and American projector products used ANSI lumens, which also gradually became the habit of everyone. Later, the projector production in the Japanese region, Japan's projection products are becoming more and more abundant, only to have ISO lumens.

As long as the brightness of the projector is fixed, the ANSI lumen figure is larger than the ISO lumen. the ratio between ANSI lumens and ISO lumens (ISO21118) is 1:0.8. that is, 1 ANSI lumen = 0.8 ISO lumens.

It is worth noting that there are no special units to explain the lumens may be light source lumens, it does not have a uniform measurement standard. In general, light source lumens figures are surprisingly higher than their true ANSI lumens.