Diopter lens, relay lens, collimator lens

增距鏡 屈光鏡 中繼鏡

Project the test pattern at the specific distance
◦Make the lightbox compact (縮小燈箱空間)
◦Make the light panel smaller (縮小燈源面板尺寸)
◦Easy for the camera to capture the image of the whole field (相機可抓取全部畫面)

Application: Relative narrow FOV focusing/testing
(適用相對較小視角之相機檢測)
◦FOV < 135 degree
◦Limited space for focusing alignment (調焦時空間有所限制)