Distribution-index And Image Properties Of Hexagon-aperture Microlens Arrays

The optoelectronic instrument and optical element all had great changes with the development of modern optical and optelectronic technology. More and more applications have occurred with the opponents of microlens array. Diffractive lens and gradient refractive index lens, which made optoelectronic instrument miniaturization, array, and integration.Microoptical components and microelectronical devices and micromechanical system are combined with each other in the free space in order to obtain higher performance and efficiency. Microoptical technology have divided into different type refractive and diffractive microoptical components in the past few years.In this paper, the microlens array with hexagonal aperture and buried in a glass substrate was fabricated with photolithography and ion-exchange techniques including the design of mask parameters and experimental parameters based on the previous work, such as size of aperture, space lenghth of aperture, the proportion of melt salts and time and temperature in the ion-exchange process and process of removing titanium and so on. This made the planar microlens array sample close to ideal refractive index, and the optical properties of plane microlens array become better. The optical properties and imaging characteristics of the single plane microlens and double plane microlens are analyzed theoretically.The refractive index distributions of planar microlens in different directions are analyzed in this paper based on the diffusion theory of symmetrical aperture with Tl--Na- ion-exchange. The refractive index distribution area is centrosymmetric by the exchanging windows. The refractive index of the lens which are buried in glass substrate are close to half a spherical area, so we analyzed the transmission rule of light based on the model of R. K. Luneburg’s lens.The appearance and cutting section of the microlens array, multiple imaging, focal length, focused spot and distribution of refractive index are measured and analyzed. However, the imaging conditions and characteristics of comprehensive image of plane microlens array are analyzed based on the non-Gaussian imaging properties of optical element arrays.The hexagon-aperture microlens arrays is widely used in the field of three dimensional integrated systems, and the plane microlens array have a good application prospect in three dimensional imaging systems.