Lumen per Square Foot Steradian to Blondel Conversion

Convert between Lumen per Square Foot Steradian and Blondel quickly and accurately.

lm/(ft²·sr)
blondel

How to Convert Lumen per Square Foot Steradian to Blondel

Conversion Formula

1 lm/(ft²·sr) = 33.816 blondel
1 blondel = 0.03 lm/(ft²·sr)

Example

Convert 15 lm/(ft²·sr) to blondel:

15 lm/(ft²·sr) = 15 × 33.816 blondel = 507.237 blondel

Unit Information

Learn about the luminance units you're converting between

Lumen per Square Foot Steradian

lm/(ft²·sr)

Definition

The Lumen per Square Foot Steradian is an imperial unit of luminance that shows the relationship between luminous flux, area, and solid angle using square feet. It is equivalent to 10.7639104167 candela per square meter.

History/Origin

This unit was developed for use in countries employing imperial measurements, providing a way to express luminance in terms of square feet while maintaining the relationship to luminous flux and solid angle. It bridges metric and imperial systems in lighting applications.

Current Use

Used in lighting design and engineering in countries using imperial units, particularly in architectural lighting and display specifications. Common in applications where square footage is the standard area measurement and precise luminance control is required.

Multiplier

10.764

Offset

0

Blondel

blondel

Definition

The Blondel is a non-SI unit of luminance equal to 0.3183098862 candela per square meter, identical to the apostilb. It is named after the French physicist André Blondel and is used in some specialized photometric applications.

History/Origin

Named after the French physicist André Blondel, this unit was developed as part of early photometric systems. It is identical to the apostilb and provides an alternative way to express low luminance values in certain technical and historical contexts.

Current Use

Used in specialized photometric applications and historical contexts where the Blondel unit is preferred. Occasionally found in older technical specifications and certain branches of photometry where traditional units are still used.

Multiplier

0.318

Offset

0

Lumen per Square Foot Steradian to Blondel Conversion Table

Lumen per Square Foot Steradian [lm/(ft²·sr)] Blondel [blondel]
1 lm/(ft²·sr) 33.815822 blondel
10 lm/(ft²·sr) 338.158219 blondel
25 lm/(ft²·sr) 845.395547 blondel
50 lm/(ft²·sr) 1690.791094 blondel
100 lm/(ft²·sr) 3381.582189 blondel
0 lm/(ft²·sr) 0E+0 blondel
-10 lm/(ft²·sr) -338.158219 blondel
-40 lm/(ft²·sr) -1352.632875 blondel