photometric unit

例句：

1. 1. The photometric unit is used to measure the brightness of light.
   光度单位用于测量光的亮度。
2. 2.The scientist used a photometric unit to measure the color of the paint.
   科学家使用一个光度单位来测量油漆的颜色。
3. 3. The photometric unit was used to calculate the energy output of the device.
   光度单位被用来计算设备的能源输出。