What is the Difference Between Candela and Lumen?

Lumens and candelas are both units used to measure the luminous intensity of lighting devices, but they measure different aspects of the light emitted. Here are the key differences between the two:

• Lumens (L): Lumens refer to the total amount of light emitted by a lighting apparatus. The higher the lumens value of a lighting device, the larger the area it illuminates. Lumens are a measure of the total light produced, similar to the wattage of a light bulb.
• Candelas (CD): Candelas refer to the amount of light emitted by a lighting device in a particular direction. Candelas emphasize how far that light reaches. It is a measure of the intensity or throw of the light.

In simpler terms, lumens are the 'amount' of light, whereas candelas focus on how far the light reaches. For example, a flashlight with high lumens and low candelas would provide a wide area of brightness but not reach very far, while a flashlight with high candelas would have a more focused beam that reaches a longer distance.

When choosing a lighting device, it is essential to consider both lumens and candelas to ensure the device meets your specific needs. For instance, if you need a flashlight for long-distance illumination, you should pay attention to the maximum amount of candelas. If you need a bright flashlight for shorter distances, you should focus more on the lumens value.

Comparative Table: Candela vs Lumen

The difference between candela and lumen lies in the aspects of lighting they measure. Here is a table comparing the two:

In summary, lumens measure the total brightness of a lighting device, while candelas focus on the beam intensity and throw. Lumens are useful for illuminating a large area evenly, while candelas are useful for focusing light on a specific direction or spot.