ANSI vs. NITS : CCI Solutions

NIT-Picking
Screen brightness - ANSI Lumens versus NITS - what is the difference?

Both ANSI and NIT are measurements of light. Here you will learn the difference between the two measurements, and how you can apply them to screen brightness.

Question:
What is the difference between ANSI Lumens and NITS? Specifically, which is brighter, why, and how do these standards relate? For example, which is brighter: 5,000 NITS or 10,000 ANSI Lumens?

Answer:
In short, the NIT is a measurement of direct light while a lumen is a measurement of reflected light.

ANSI Lumens (ANSI) are used to describe projection devices and NITS are used to describe displays. Both light measurements are based on a candela, the basic unit of measurement of total light output from a source (AKA Luminous Intensity).

An ANSI lumen is the amount of light energy reflecting off one square meter area at a constant distance of one meter from a one candela light source. A NIT (cd/m2) is an amount of emanating light equal to one candela per square meter.

To illustrate the difference, think of a light bulb and a wall. If you look directly at the light bulb, it is very bright (think NITS). If you hold the light bulb one meter from the wall and look at the same size area as the bulb on the wall it will be significantly less bright (think ANSI). The reflecting light is simply not as strong as the bulb itself.

A foot-lambert is a measurement of brightness equal to one lumen per square meter. One NIT is equal to approximately 0.292-foot lamberts, or 3.426 NITS equal one single foot-lambert. Thus, for the same surface area, a NIT is much brighter.The direct source (NIT) is always stronger than a reflection (ANSI), so one candela over one square meter (NIT) is brighter than the light reflected by one candela onto one square meter at a distance of one meter (ANSI Lumens). We are now able to answer the question, "which is brighter: 5,000 NITS or 10,000 ANSI Lumens?" Using the measurements above, we see that 5000 NITS is equal to 17,130 ANSI Lumens. NITS are brighter.

Question:
What does cd/m2 mean?

Answer:
It stands for Candelas per One Square Meter and is the measurement for a NIT.