Phase detect technology focuses lens in 0.3s at 25lx

Traditional smartphone AutoFocus (AF) algorithms use a contrast detection measurement and multiple frames to adjust the lens focus. This trial-and-error method can take over 1.2s to find focus in an image. ON Semiconductor’s PDAF technology uses two pixels to measure phase information from the target image. This phase information is then used to calculate the direction and the amount the lens needs to move to focus in less than 0.3s, depending on focus actuator speed.

ON Semiconductor has also implemented a unique pixel micro-lens structure which maintains sensitivity in the PDAF pixels and ensures enough light is captured for PDAF to perform in low-light conditions as low as 25lx (similar to a dimly lit room). Competing technologies on the market employ methods that compromise pixel sensitivity and low light auto focus performance.

“ON Semiconductor’s PDAF technology is the result of innovations in both pixel and optical stack design. The outcome is a reduction of auto focus time by nearly a factor of four and delivers a great experience to the mobile device user. The leading low-light capability of our technology enables smartphone manufacturers to deliver a fast AF experience across all light levels to their customers,” commented Shung Chieh, Vice President, Mobile and Consumer Division, ON Semiconductor.

ON Semiconductor will be demonstrating its latest image sensor technology and products at Mobile World Congress 2015 in Barcelona next week.