The present invention discloses a portable, high-performance optical imaging device (101) for investigation of Cervical Intraepithelial Neoplasia especially CIN-II and CIN-III comprising infrared camera assembly (10), controller (40) and display screen (50). The said optical device (101) captures Grayscale images and Colour images, simultaneously, which are stored and analyzed by the controller (40) and results displayed on display screen (50). Figure 1.