What are the factors that affect the transmission efficiency of optocouplers?

The transmission efficiency of optocouplers (optocouplers) is influenced by various factors, including the following aspects:
Efficiency of light source:
The light-emitting diode (LED) or laser diode used as the light source in the optocoupler directly affects the transmission efficiency of the optocoupler.
Sensitivity of photodetectors:
The sensitivity of photodetectors (usually photosensitive transistors) to light signals also has a significant impact on transmission efficiency.
Barrier of optical path:
In optocouplers, there may be optical path barriers between the light source and the photodetector, such as air gaps or optical materials, which can affect the transmission efficiency of optical signals.
Environmental factors:
Changes in temperature and light intensity can both affect the transmission efficiency of optocouplers.
Power supply voltage:
The variation of power supply voltage can affect the brightness of the light source in the optocoupler, thereby affecting the transmission efficiency.
Current limitation and resistance:
The current limitation and resistance in the input and output circuits can also affect the transmission efficiency of optocouplers.
Aging of optocouplers:
Over time, the performance of optocouplers may decrease, typically manifested as a decrease in CTR.
External Electromagnetic Interference (EMI):
External electromagnetic interference may affect the electrical signal of the optocoupler, thereby affecting its transmission efficiency.