照明是每单位区域表面上的总发光通量。它以Lux（LX）为单位。
1 cd/m² = 0 ph
1 ph = 10,000 cd/m²
例子:
将15 每平方米烛台转换为光：
15 cd/m² = 0.002 ph
| 每平方米烛台 | 光 |
|---|---|
| 0.01 cd/m² | 1.0000e-6 ph |
| 0.1 cd/m² | 1.0000e-5 ph |
| 1 cd/m² | 0 ph |
| 2 cd/m² | 0 ph |
| 3 cd/m² | 0 ph |
| 5 cd/m² | 0.001 ph |
| 10 cd/m² | 0.001 ph |
| 20 cd/m² | 0.002 ph |
| 30 cd/m² | 0.003 ph |
| 40 cd/m² | 0.004 ph |
| 50 cd/m² | 0.005 ph |
| 60 cd/m² | 0.006 ph |
| 70 cd/m² | 0.007 ph |
| 80 cd/m² | 0.008 ph |
| 90 cd/m² | 0.009 ph |
| 100 cd/m² | 0.01 ph |
| 250 cd/m² | 0.025 ph |
| 500 cd/m² | 0.05 ph |
| 750 cd/m² | 0.075 ph |
| 1000 cd/m² | 0.1 ph |
| 10000 cd/m² | 1 ph |
| 100000 cd/m² | 10 ph |
规则