(EN)
A method and apparatus for reading a microbead having a code thereon is provided wherein the code is projected on and read from a Fourier plane. The microbead may be 1-1000 microns (um) or smaller in feature size. The code is projected on the Fourier plane by scattering input light off the microbead. The scattered light from the microbead is directed through an optical arrangement having a transform lens for projecting the code on the Fourier plane, and read on the Fourier plane using a charge coupled device (CCD) or other similar device. The code may include periodic layers of material having different refractivities or phase, including index of refraction differences; periodic spatial modulations having a different phase or amplitude; a periodic binary phase change used to code information in the Fourier plane; a photonic crystal used to encode the information on the microbead, wherein a pattern of holes causes interference between incident and scattered light to form spatial and spectral patterns in the far field that are unique to the pattern of holes; or may be formed in the microbead using a single photoactive inner region, a series of longitudinal holes, different fluorescence regions, or concentric rings of material in a preform.
(ZH) 提供一种用于读取其上具有代码的微珠的方法和设备,其中代码被投射在傅里叶平面上并且从傅里叶平面读取该代码。微珠的形体尺寸可以是1-1000微米(μm)或更小。通过使入射光散射离开微珠而将代码投射在傅里叶平面上。将从微珠散射的光引导通过具有用于将代码投射在傅里叶平面上的变换透镜的光学装置,并利用电荷耦合器件(CCD)或其他类似装置在傅里叶平面上读取代码。代码可以包括具有不同折射率或相位、包括折射率差的周期性材料层;具有不同相位或振幅的周期性空间调制;用于对傅里叶平面内的信息进行编码的周期性二元相位变化;用于对微珠上的信息进行编码的光子晶体,其中穿孔图案导致入射光和散射光之间的干涉在远场中形成空间和光谱特性曲线,这些空间和光谱特性曲线对于穿孔图案是唯一的;或者可以利用单个光敏内区、一系列纵向孔、不同的荧光区、或者预制件中的材料的同心环而在微珠中形成代码。