The formula to calculate Candela (\(cd\)) from Lumens (\(lm\)) is:
\[ cd = \frac{lm}{2 \pi (1 - \cos(\theta / 2))} \]
Where:
Lumens (lm) measure the total amount of visible light emitted by a source. Candela (cd) measures the luminous intensity in a specific direction.
The apex angle is the angle at the tip of a cone, defining the spread of the light.
Let's assume the following values:
Using the formula:
\[ cd = \frac{1000}{2 \pi (1 - \cos(30 / 2))} \]
Evaluating:
\[ cd = \frac{1000}{2 \pi (1 - \cos(15))} \]
The Candela is approximately 4670.8 cd.
Lumens (lm) | Apex Angle (degrees) | Candela (cd) |
---|---|---|
100 | 10 | 4,182.4525 |
100 | 20 | 1,047.6063 |
100 | 30 | 467.0838 |
100 | 40 | 263.9063 |
100 | 50 | 169.8700 |
100 | 60 | 118.7949 |
100 | 70 | 88.0048 |
100 | 80 | 68.0279 |
100 | 90 | 54.3389 |
200 | 10 | 8,364.9049 |
200 | 20 | 2,095.2127 |
200 | 30 | 934.1676 |
200 | 40 | 527.8125 |
200 | 50 | 339.7400 |
200 | 60 | 237.5897 |
200 | 70 | 176.0097 |
200 | 80 | 136.0557 |
200 | 90 | 108.6778 |
300 | 10 | 12,547.3574 |
300 | 20 | 3,142.8190 |
300 | 30 | 1,401.2514 |
300 | 40 | 791.7188 |
300 | 50 | 509.6099 |
300 | 60 | 356.3846 |
300 | 70 | 264.0145 |
300 | 80 | 204.0836 |
300 | 90 | 163.0167 |
400 | 10 | 16,729.8098 |
400 | 20 | 4,190.4254 |
400 | 30 | 1,868.3352 |
400 | 40 | 1,055.6250 |
400 | 50 | 679.4799 |
400 | 60 | 475.1795 |
400 | 70 | 352.0193 |
400 | 80 | 272.1114 |
400 | 90 | 217.3556 |
500 | 10 | 20,912.2623 |
500 | 20 | 5,238.0317 |
500 | 30 | 2,335.4190 |
500 | 40 | 1,319.5313 |
500 | 50 | 849.3499 |
500 | 60 | 593.9743 |
500 | 70 | 440.0242 |
500 | 80 | 340.1393 |
500 | 90 | 271.6945 |
600 | 10 | 25,094.7147 |
600 | 20 | 6,285.6381 |
600 | 30 | 2,802.5028 |
600 | 40 | 1,583.4375 |
600 | 50 | 1,019.2199 |
600 | 60 | 712.7692 |
600 | 70 | 528.0290 |
600 | 80 | 408.1671 |
600 | 90 | 326.0334 |
700 | 10 | 29,277.1672 |
700 | 20 | 7,333.2444 |
700 | 30 | 3,269.5866 |
700 | 40 | 1,847.3438 |
700 | 50 | 1,189.0899 |
700 | 60 | 831.5641 |
700 | 70 | 616.0338 |
700 | 80 | 476.1950 |
700 | 90 | 380.3723 |
800 | 10 | 33,459.6196 |
800 | 20 | 8,380.8507 |
800 | 30 | 3,736.6703 |
800 | 40 | 2,111.2500 |
800 | 50 | 1,358.9598 |
800 | 60 | 950.3589 |
800 | 70 | 704.0387 |
800 | 80 | 544.2228 |
800 | 90 | 434.7112 |
900 | 10 | 37,642.0721 |
900 | 20 | 9,428.4571 |
900 | 30 | 4,203.7541 |
900 | 40 | 2,375.1563 |
900 | 50 | 1,528.8298 |
900 | 60 | 1,069.1538 |
900 | 70 | 792.0435 |
900 | 80 | 612.2507 |
900 | 90 | 489.0501 |
1000 | 10 | 41,824.5246 |
1000 | 20 | 10,476.0634 |
1000 | 30 | 4,670.8379 |
1000 | 40 | 2,639.0625 |
1000 | 50 | 1,698.6998 |
1000 | 60 | 1,187.9487 |
1000 | 70 | 880.0483 |
1000 | 80 | 680.2785 |
1000 | 90 | 543.3890 |