The Micro-optics Label System Based On Six-reflection Fold Annular Aperture Lens

The micro-optics label is a new type of tag identification technology,the visual micro-optics tag is only a few millimeters in size,much smaller than the traditional barcode,but with millions of times increased in its storage capacity,and even more safety by eliminating the risk of information leakage that exists in barcode widely,which brought it a promising application prospects in the future,such as mobile payment,augmented reality and so on.Although many of the mobile terminals have a camera,the existing mirco-optics label can achieve remote receiving for the micro label only though the cameras which have a large aperture and a long focal length.In this thesis,a six-reflection fold annular aperture ultra-thin lens was designed to apply to receiving terminal with the aid of optical engineering software--Zemax.The imaging performance of the micro-optics label system based on the six-reflection fold annular aperture ultra-thin lens is analyzed by comparing the simulated images obtained by the micro-optics label system.Finally,a software processing method--homomorphic filtering has been used to correct for the system luminance non-uniformity.The front surface of the six-reflection fold annular aperture ultra-thin lens was consisted of a plane mirror and the rear surface was focused by four concentric annular aspheric reflectors to the image plane.The outer diameter of the lens is 28 mm,the effective focal length is 38 mm,and the thickness of the lens is 5 mm.With the help of the clear aperture condition of a four-reflection fold annular aperture lens,the structure of the equipment was improved to increase the number of reflections,effectively reduce the thickness of the lens,and enlarge the focal length of lens.In this work,an optimized design and analysis to the whole system were reported.It was based on the annular aperture ultra-thin lens as receiving terminal by using the six-reflection fold annular aperture lens,which can greatly increase the receiving distance and reduce the distortion of simulated images.In the end,the algorithm of homomorphic filtering has been demonstrated to correct for the system luminance non-uniformity effectively by comparing the simulated images before and after homomorphic filtering.