LED light output will change with different chip types, packaging methods and other differences. But there is no uniform standard to measure its brightness in the world. Generally speaking, the total luminous amount of LED is measured by the height value of one light point in the axial direction, and expressed in (MCD) candle. A LED with a very high degree does not mean that its light output is very high. To calculate its total light output, we must take its luminous angle into account. The perspective of LED is also a function of LED chip type and the function of light distribution or astigmatism of its epoxy resin shell. The LED of different chip and package shell will have different brightness value. If two LEDs have the same brightness value, the larger the light angle is, the greater the light output.