The Focusing Mechanisms Of Camera Modules

The focusing mechanisms of camera modules primarily include the following types:

Contrast Detection Auto Focus ( CDAF):

This method determines the focus position by analyzing changes in image contrast. The focus is considered to be accurate when the contrast is at its peak.

Phase Detection Auto Focus ( PDAF):

This technique uses dedicated phase detection pixels to measure the phase difference of light from the object, allowing for rapid determination of the focus position PDAF is generally faster than CDAF, especially in low light conditions.

Manual Focus (MF):

Users manually adjust the focus position by rotating the lens or using a slider on the camera or phone interface. This method is typically used in situations that require precise control over the focus, such as macro photography.

Fixed Focus ( FF):

The focus position of the camera module is fixed and is suitable for scenes where the focal distance does not need to be adjusted, such as certain security.

Laser/Infrared Assisted Auto Focus (Laser/Infrared AF):

This method uses laser or in frared light to assist in focusing, especially in light conditions, enhancing the accuracy and speed of the focus.

Hybrid Focusing System (Hybrid AF):

This system combines the advantages of both PDAF andDAF focusing technologies. It is commonly used in high-end cameras and phones to provide fast and accurate auto focus performance.

Dual Pixel Auto Focus (Dual Pixel AF）：

Each pixel includes two photodiodes that can measure the phase difference simultaneously, providing more precise focusing performance.

Depth Sensing Auto Focus (Depth Sensing AF):

This method uses a depth sensor (such as ToF, structured light) to measure the distance to the object, thereby assisting in focusing. This technology is particularly useful in low light conditions.

Each focusing method has its own characteristics and applicable scenarios. The choice of which method to use depends on the specific application requirements and environmental conditions