Calculateur de Luminosité & Foot-Lamberts de Projecteur

How to use it: enter screen size, rated lumens, an estimated delivered-output percentage, screen gain and your comparison target. This keeps marketing output separate from the lumens assumed to reach the screen.

Formula. Foot-lamberts = delivered lumens x gain / screen area in square feet. Approximate cd/m² = fL x 3.426. Reverse rated lumens also accounts for the entered delivery percentage.

Example. A 2500-lumen projector modeled at 70% output delivers 1750 lumens before screen gain and area are applied.

Le résultat ci-dessus utilise exactement ces valeurs. Cet instantané est inclus à l’impression pour comparer la sortie aux mesures d’origine.

Screen diagonal

120 in

Aspect width

16

Aspect height

9

Rated lumens

2500

Estimated delivered output

70 %

Screen gain

1

Target brightness

16 fL

Résultat principal: Estimated screen brightness: 41.0 fL.

• Measure from the datum or reference edge described by this tool, and do not mix inside, outside and centerline dimensions.
• Keep inputs in the displayed units and preserve more precision than the final cutting or purchasing tolerance requires.
• When the result is close to a limit, verify it with a test piece, field measurement, manufacturer drawing or qualified project professional.

This is an idealized uniform-screen estimate. Calibration mode, zoom, lamp/laser age, optical losses, screen directionality, ambient light, contrast and measurement position affect the real image. Measure the installed system when brightness matters.