Multifocal array camera system design

Traditional cameras rely on focusing mechanisms for high-performance imaging over a large depth range. However, focusing mechanisms are usually complicated, bulky, and costly. Here we consider multifocal array cameras that eliminate the need for focusing mechanisms. In the system, lenses with different focal lengths cover different depth ranges, and focusing is achieved digitally by selecting images from the designated channels. Eliminating the need to focus enables simple high-performance designs for individual cameras. Various lens design techniques, including the selection of design forms, aberration correction, athermalization, and lens desensitizing, are discussed in detail.