本文為五百萬畫素廣角監視器鏡頭設計，其鏡頭組成為7片玻璃鏡片與二片平板玻璃所組成，其中含有二片非球面鏡片。另初階設計為有效焦距 1.649 mm、F/# 2.1、最大半視角80度。 廣角監視器鏡頭成像品質，MTF在180 lp/mm至少大於0.618，橫向色差小於0.623 um，F-theta distortion 小於0.85%，相對照度大於93%。 本研究主要探討與分析相對照度，在半視角80之鏡頭設計，由於視角越大相對照度會越嚴重，所以，在本文中會詳述相對照度形成的原因並推導其公式，相對照度與鏡面之介面穿透率、鏡片內部穿透率與鏡頭成像立體角有關。 ;This article is designed for a five-million-pixel wide-angle monitor lens. The lens consists of seven glass lenses and two flat glass plates, which contain two aspherical lenses. The other initial design is effective focal length 1.649 mm, F/# 2.1, maximum half angle of view 80 Wide-angle monitor lens imaging quality, MTF is at least greater than 0.618 at 180 lp/mm, lateral chromatic aberration is less than 0.623 um, F-theta distortion is less than 0.85%, and contrast is greater than 93%. This study mainly discusses the contrast with the analysis. In the lens design with half angle of view, the larger the angle of view, the more serious the contrast will be. Therefore, in this paper, the reason for the formation of the contrast is deduced and the formula is derived. The interface penetration rate and the internal transmittance of the lens are related to the solid angle of the lens image.